Revision Guide For Student Nurses - Part 2

Producing A Radiographic Image - Answers

Lisa Spencer — Tue, 05 Jul 2011 13:35:48 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Lisa Spencer on 05/07/2011 14:35:48

Producing A Radiographic Image - Answers

ANSWERS

Define radiography.
The production of diagnostic films by exposure to x-rays.
Define radiology.
Radiation physics, although commonly defined as the interpretation of the radiographic image.
Which 2 members of the electromagnetic spectrum possess the highest frequency and the shortest wavelength?
- X-rays.
- Gamma rays.
What are electromagnetic radiations made up of?
Discrete energy packets known as photons or quanta.
What 4 properties are possessed by all the members of the electromagnetic spectrum?
- They can pass through a vacuum.
- They travel at a uniform speed through a vacuum (3 x 10 to the power of 8 m/s).
- They are able to interact with matter by being absorbed or scattered.
- A medium is not required for transmission.
What 3 special properties do x-rays possess?
- The ability to penetrate substances opaque to visible light.
- The ability to produce an image on photographic film.
- The ability to cause certain substances to fluoresce.
What is an atom?
The smallest particle of an element that retains all the properties of that element. It consists of a positively charged nucleus with negatively charged electrons moving around it in orbit.
What is meant by the "atomic number" of an element?
The unique number of protons possessed by each element.
What is a compound?
A combination of 2 or more elements. One usually possesses positive ions, whilst the other possesses negative ions.
X-rays are generated in the tube head of the x-ray machine. Name the 2 types of tube head available.
- Stationary or fixed anode.
- Rotating anode.
Why is a rotating anode superior to a stationary anode?
- More efficient means of heat removal.
- Allows longer exposure times.
A rotating anode is mounted upon a molybdenum rod which spins at speeds of up to 10,000 rpm. Why is molybdenum used?
It is a poor conductor, and therefore prevents the heater from overheating.
At what angle is the target area set on a rotating anode?
6-20 degrees.
What is the cathode?
The negatively charged electrode of the tube head consisting of a coiled tungsten wire filament.
Why is tungsten the material of choice for the cathode?
Its high atomic number means that it has a very high melting point and it also a good emitter of electrons.
What is the anode?
The positively charged electrode of the tube head. This is made of tungsten or rhenium tungsten since its atoms are large and efficient at impeding the incident electrons.
How are x-ray photons produced within the tube head?
Fast moving incident electrons are produced by the cathode (filament) which collide with the atoms of the anode (target). These collisions generate x-ray photons. The faster the incident electrons, the more energy they have to lose, and thus the greater the intensity of the primary beam.
What 2 factors increase the speed of the electrons travelling from the filament to the target?
- A high electrical potential distance applied between the filament and target.
- A glass envelope containing a vacuum enclosing the cathode, anode and part of the copper stem.
What is the glass envelope contained within and why?
An oil bath, which acts as a heat sink and electrical insulator.
What is the term used to describe a small electrical current passed through a filament and the subsequent release of an electron cloud following heat generation?
Thermionic emission.
What is the function of the step-down or filament transformer?
This decreases the mains current since only a small current is required to heat the filament.
What is the function of the step-up or high-tension transformer?
This increases the voltage of the mains supply.
What is the function of the focusing cup?
This forms the electrons into a narrow beam.
What is the focusing cup made of?
Nickel or molybdenum.
Why is the target set in a copper stem in a stationary anode tube?
Copper is a good heat conductor and is therefore efficient at removing heat from the target.
What is meant by the terms "actual focal spot" and "effective focal spot"?
- Actual focal spot - the area of the target upon which the electrons impinge; this is the area over which heat is produced.
- Effective focal spot - this should ideally be a point source; the x-ray beam appears to originate from a much smaller area as a result of the angulation of the target.
How is focal spot size adjusted?
Some x-ray machines have 2 different sized filaments at the cathode. The fine focus is produced by the smaller of the two; a narrower electron beam is generated and thus a smaller effective and actual focal spot size. The coarse (or broad) focus is produced by the larger filament, resulting in a larger effective and actual focal spot size.
What is the advantage of the fine focus?
Very fine radiographic definition is produced, making it suitable for areas such as the limbs.
What is the advantage of the coarse (or broad) focus?
Higher exposures may be selected, making it suitable for dense areas of the anatomy such as the chest and abdomen.
What is the main disadvantage of the fine focus?
Exposure factors are limited due to the large amount of heat generated over a very small area.
What is the main disadvantage of the coarse (or broad) focus?
Image definition is poorer than that produced with the fine focus.
Define the "penumbra effect".
Blurring of the margins of an image related to the geometry of the primary beam.

Producing A Radiographic Image - Answers

Arlo Guthrie — Tue, 21 Apr 2009 06:00:19 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:00:19

ANSWERS

Define radiography.
The production of diagnostic films by exposure to x-rays.
Define radiology.
Radiation physics, although commonly defined as the interpretation of the radiographic image.
Which 2 members of the electromagnetic spectrum possess the highest frequency and the shortest wavelength?
- X-rays.
- Gamma rays.
What are electromagnetic radiations made up of?
Discrete energy packets known as photons or quanta.
What 4 properties are possessed by all the members of the electromagnetic spectrum?
- They can pass through a vacuum.
- They travel at a uniform speed through a vacuum (3 x 10 to the power of 8 m/s).
- They are able to interact with matter by being absorbed or scattered.
- A medium is not required for transmission.
What 3 special properties do x-rays possess?
- The ability to penetrate substances opaque to visible light.
- The ability to produce an image on photographic film.
- The ability to cause certain substances to fluoresce.
What is an atom?
The smallest particle of an element that retains all the properties of that element. It consists of a positively charged nucleus with negatively charged electrons moving around it in orbit.
What is meant by the "atomic number" of an element?
The unique number of protons possessed by each element.
What is a compound?
A combination of 2 or more elements. One usually possesses positive ions, whilst the other possesses negative ions.
X-rays are generated in the tube head of the x-ray machine. Name the 2 types of tube head available.
- Stationary or fixed anode.
- Rotating anode.
Why is a rotating anode superior to a stationary anode?
- More efficient means of heat removal.
- Allows longer exposure times.
A rotating anode is mounted upon a molybdenum rod which spins at speeds of up to 10,000 rpm. Why is molybdenum used?
It is a poor conductor, and therefore prevents the heater from overheating.
At what angle is the target area set on a rotating anode?
6-20 degrees.
What is the cathode?
The negatively charged electrode of the tube head consisting of a coiled tungsten wire filament.
Why is tungsten the material of choice for the cathode?
Its high atomic number means that it has a very high melting point and it also a good emitter of electrons.
What is the anode?
The positively charged electrode of the tube head. This is made of tungsten or rhenium tungsten since its atoms are large and efficient at impeding the incident electrons.
How are x-ray photons produced within the tube head?
Fast moving incident electrons are produced by the cathode (filament) which collide with the atoms of the anode (target). These collisions generate x-ray photons. The faster the incident electrons, the more energy they have to lose, and thus the greater the intensity of the primary beam.
What 2 factors increase the speed of the electrons travelling from the filament to the target?
- A high electrical potential distance applied between the filament and target.
- A glass envelope containing a vacuum enclosing the cathode, anode and part of the copper stem.
What is the glass envelope contained within and why?
An oil bath, which acts as a heat sink and electrical insulator.
What is the term used to describe a small electrical current passed through a filament and the subsequent release of an electron cloud following heat generation?
Thermionic emission.
What is the function of the step-down or filament transformer?
This decreases the mains current since only a small current is required to heat the filament.
What is the function of the step-up or high-tension transformer?
This increases the voltage of the mains supply.
What is the function of the focusing cup?
This forms the electrons into a narrow beam.
What is the focusing cup made of?
Nickel or molybdenum.
Why is the target set in a copper stem in a stationary anode tube?
Copper is a good heat conductor and is therefore efficient at removing heat from the target.
What is meant by the terms "actual focal spot" and "effective focal spot"?
- Actual focal spot - the area of the target upon which the electrons impinge; this is the area over which heat is produced.
- Effective focal spot - this should ideally be a point source; the x-ray beam appears to originate from a much smaller area as a result of the angulation of the target.
How is focal spot size adjusted?
Some x-ray machines have 2 different sized filaments at the cathode. The fine focus is produced by the smaller of the two; a narrower electron beam is generated and thus a smaller effective and actual focal spot size. The coarse (or broad) focus is produced by the larger filament, resulting in a larger effective and actual focal spot size.
What is the advantage of the fine focus?
Very fine radiographic definition is produced, making it suitable for areas such as the limbs.
What is the advantage of the coarse (or broad) focus?
Higher exposures may be selected, making it suitable for dense areas of the anatomy such as the chest and abdomen.
What is the main disadvantage of the fine focus?
Exposure factors are limited due to the large amount of heat generated over a very small area.
What is the main disadvantage of the coarse (or broad) focus?
Image definition is poorer than that produced with the fine focus.
Define the "penumbra effect".
Blurring of the margins of an image related to the geometry of the primary beam.

Anaesthetic Circuits - Key Notes

alison meecham — Mon, 04 Apr 2011 13:46:20 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by alison meecham on 04/04/2011 14:46:20

Anaesthetic Circuits - Key Notes

Name	Type	Weight Range	Bag	Co-Axial	Nitrous	Gas flow
Circle system	Closed	10kg and above	Re-Breathing closed	No	No	5-10mls per kg if closed (+10mls if low flow)
To & fro (Waters)	Closed	10kg and above	Re-breathing closed	No	No	5-10mls per kg if closed (+10mls if low flow)
Magill	Semi-closed	7-35kg	Reservoir closed	No	Yes	Circuit factor 1-1.5
Lack	Semi-closed	7-40kg	Reservoir closed	Yes	Yes	Circuit factor 1-1.5
Parallel Lack	Semi-closed	7-40kg	Reservoir closed	No	Yes	Circuit factor 1-1.5
Ayres T piece	Semi-closed	Up to 10kg	None	No	Yes	Circuit factor 2.5-3
Ayres with Jackson Rees mod.	Semi-closed	Up to 10kg	Reservoir open-ended	No	Yes	Circuit factor 2.5-3
Bain D	Semi-closed	10-30kg	Reservoir closed	Yes	Yes	Circuit factor 2.5-3
Bain E	Semi-closed	Up to 10kg	None	Yes	Yes	Circuit factor 2.5-3
Bain F	Semi-closed	Up to 10kg	Reservoir open-ended	Yes	Yes	Circuit factor 2.5-3

Anaesthetic Circuits - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 10:33:59 GMT

Revision 2 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:33:59

Types Of Anaesthesia Anaesthetic Circuits - Key Notes

Name	Type	Weight Range	Bag	Co-Axial	Nitrous	Gas flow
Circle system	Closed	10kg and above	Re-Breathing closed	No	No	5-10mls per kg if closed (+10mls if low flow)
To & fro (Waters)	Closed	10kg and above	Re-breathing closed	No	No	5-10mls per kg if closed (+10mls if low flow)
Magill	Semi-closed	7-35kg	Reservoir closed	No	Yes	Circuit factor 1-1.5
Lack	Semi-closed	7-40kg	Reservoir closed	Yes	Yes	Circuit factor 1-1.5
Parallel Lack	Semi-closed	7-40kg	Reservoir closed	No	Yes	Circuit factor 1-1.5
Ayres T piece	Semi-closed	Up to 10kg	None	No	Yes	Circuit factor 2.5-3
Ayres with Jackson Rees mod.	Semi-closed	Up to 10kg	Reservoir open-ended	No	Yes	Circuit factor 2.5-3
Bain D	Semi-closed	10-30kg	Reservoir closed	Yes	Yes	Circuit factor 2.5-3
Bain E	Semi-closed	Up to 10kg	None	Yes	Yes	Circuit factor 2.5-3
Bain F	Semi-closed	Up to 10kg	Reservoir open-ended	Yes	Yes	Circuit factor 2.5-3

Types Of Anaesthesia - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 10:24:56 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:24:56

Name	Type	Weight Range	Bag	Co-Axial	Nitrous	Gas flow
Circle system	Closed	10kg and above	Re-Breathing closed	No	No	5-10mls per kg if closed (+10mls if low flow)
To & fro (Waters)	Closed	10kg and above	Re-breathing closed	No	No	5-10mls per kg if closed (+10mls if low flow)
Magill	Semi-closed	7-35kg	Reservoir closed	No	Yes	Circuit factor 1-1.5
Lack	Semi-closed	7-40kg	Reservoir closed	Yes	Yes	Circuit factor 1-1.5
Parallel Lack	Semi-closed	7-40kg	Reservoir closed	No	Yes	Circuit factor 1-1.5
Ayres T piece	Semi-closed	Up to 10kg	None	No	Yes	Circuit factor 2.5-3
Ayres with Jackson Rees mod.	Semi-closed	Up to 10kg	Reservoir open-ended	No	Yes	Circuit factor 2.5-3
Bain D	Semi-closed	10-30kg	Reservoir closed	Yes	Yes	Circuit factor 2.5-3
Bain E	Semi-closed	Up to 10kg	None	Yes	Yes	Circuit factor 2.5-3
Bain F	Semi-closed	Up to 10kg	Reservoir open-ended	Yes	Yes	Circuit factor 2.5-3

The Operating Theatre

Jess2782 — Thu, 07 Oct 2010 14:51:01 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Jess2782 on 07/10/2010 15:51:01

The Operating Theatre

QUESTIONS

List the items of theatre clothing that should be worn by all theatre personnel.
In addition to the items listed in Q1, what additional attire should be worn by the surgical team?
Why is a well-ventilated theatre essential?
In addition to the operating theatre itself, list the other areas which comprise the theatre suite.
List 10 essential properties of the theatre.
List desirable features of the theatre.
Every practice will have its own set of local rules drawn up with regard to theatre procedures. Can you name some common sense rules that will be similar across the board?
List 6 hazards that may pose a risk to theatre personnel.
Briefly outline the duties of the scrubbed nurse.
Briefly outline the duties of the circulating nurse.

The Operating Theatre

Arlo Guthrie — Tue, 21 Apr 2009 07:17:21 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:17:21

QUESTIONS

List the items of theatre clothing that should be worn by all theatre personnel.
In addition to the items listed in Q1, what additional attire should be worn by the surgical team?
Why is a well-ventilated theatre essential?
In addition to the operating theatre itself, list the other areas which comprise the theatre suite.
List 10 essential properties of the theatre.
List desirable features of the theatre.
Every practice will have its own set of local rules drawn up with regard to theatre procedures. Can you name some common sense rules that will be similar across the board?
List 6 hazards that may pose a risk to theatre personnel.
Briefly outline the duties of the scrubbed nurse.
Briefly outline the duties of the circulating nurse.

Urine Collection & Tests - Answers

James Colver — Thu, 04 Mar 2010 16:22:00 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by James Colver on 04/03/2010 16:22:00

Urine Collection & Tests - Answers

ANSWERS

What is the name of the yellow pigment which gives urine its yellow colour?
Urochrome.
What is the normal urinary output (per kg/day) of an adult dog and cat?
- Dog = 25-60mls/kg/24 hours.
- Cat = 10-20mls/kg/24 hours.
What is the term used to describe the excess production of urine?
Polyuria.
What is meant by oliguria?
Inability to pass
Decreased urine . production
What is meant by dysuria?
Painful or ineffective attempts to urinate (this term my also apply to defecation).
What is the term used to describe blood in the urine?
Haematuria
What is meant by the turbidity of urine?
Clearness of the sample; a cloudy sample is likely to contain sediment.
What causes the "pear drop" smell of the urine in ketotic patients?
Acetone.
Why should a urine sample be as fresh as possible?
The bacteria in urine will replicate quickly, and therefore an old sample will not provide a true representation. Urine may be stored for a few hours in the refrigerator, but tests should ideally be performed as soon as possible following sample collection.
List methods of collecting a urine sample from a cat.
- Natural micturition (via a metabolic cage or specially designed litter tray).
- Manual bladder expression.
- Catheterisation.
- Cystocentesis.
The veterinary surgeon asks you to obtain a free flow urine sample from a dog; why should you collect the sample mid-stream?
A mid-stream sample is less likely to be contaminated with epithelial cells or mucous from the urinary tract.
What preservative is suitable for bacteriology tests on a urine sample?
Boric acid.
What is the normal specific gravity range of urine in dogs and cats?
- Dogs = 1.018-1.045
- Cats = 1.020-1.040
What is the specific gravity of urine measured with?
A refractometer. A hydrometer may also be used, but this is less accurate.
What conditions may be indicated by a high urine specific gravity?
- Dehydration.
- Acute renal failure.
- Shock.
What conditions may be indicated by a low urine specific gravity?
- Increased water intake (polydipsia).
- Diabetes insipidus.
- Pyometra.
- Chronic hepatic dysfunction.
- Chronic renal dysfunction.
What is the normal pH range of urine in dogs and cats?
- Dogs = 5.2-6.8
- Cats = 6-7
Why are dipsticks not ideal for testing urine samples?
- Prone to contamination.
- Can only provide an estimation rather than an accurate result.
- Not reliable for pH readings.
- Very ineffective on stale samples.
What parameters are measured with a Combur 7 Test (BM Test-7)?
- pH.
- Protein.
- Glucose.
- Ketones.
- Urobilinogen.
- Bilirubin.
- Haemoglobin.
List 3 methods of measuring the pH of urine; which is the most reliable?
- Litmus paper.
- Reagent sticks.
- Electrode meter.
The electrode meter is without doubt the most reliable method.
List possible causes of haematuria.
- Cystitis and associated infection/inflammation of the urinary tract.
- Urolithiasis.
- Nephritis.
- Thrombocytopaenia.
- Trauma.
- Bladder masses.
- Drug reactions (e.g. some chemotherapeutic agents).
What is haemoglobinuria?
The presence of lysed blood in the urine.
List possible causes of haemoglobinuria.
- Autoimmune haemolytic anaemia.
- Systemic lupus erythrematosus.
- Leptospirosis.
- Babesiosis.
Urine collected free flow, from manual bladder expression or via catheterisation usually contains a small amount of protein as a result of secretions from the urogenital tract. Protein levels may also rise following parturition or during oestrus. However, true proteinuria is likely to be indicative of a clinical problem. List some causes.
- Nephritis.
- Congestive heart failure.
- Cystitis.
- Urethral inflammation.
- Vaginitis.
Name the 2 main techniques used to examine urine microscopically and state the stain used for each.
- Wet preparation - uses Sedistain (optional).
- Dry preparation - uses Leishman's stain.
List items of interest which may be observed upon the microscopic examination of urine.
- Crystals.
- Casts.
- Mucus threads.
- Spermatozoa.
- Bacteria.
- Funghi.
- Yeasts.
- Epithelial cells.
- Transitional cells.

Urine Collection & Tests - Answers

Arlo Guthrie — Mon, 20 Apr 2009 12:08:35 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 20/04/2009 13:08:35

ANSWERS

What is the name of the yellow pigment which gives urine its yellow colour?
Urochrome.
What is the normal urinary output (per kg/day) of an adult dog and cat?
- Dog = 25-60mls/kg/24 hours.
- Cat = 10-20mls/kg/24 hours.
What is the term used to describe the excess production of urine?
Polyuria.
What is meant by oliguria?
Inability to pass urine.
What is meant by dysuria?
Painful or ineffective attempts to urinate (this term my also apply to defecation).
What is the term used to describe blood in the urine?
Haematuria
What is meant by the turbidity of urine?
Clearness of the sample; a cloudy sample is likely to contain sediment.
What causes the "pear drop" smell of the urine in ketotic patients?
Acetone.
Why should a urine sample be as fresh as possible?
The bacteria in urine will replicate quickly, and therefore an old sample will not provide a true representation. Urine may be stored for a few hours in the refrigerator, but tests should ideally be performed as soon as possible following sample collection.
List methods of collecting a urine sample from a cat.
- Natural micturition (via a metabolic cage or specially designed litter tray).
- Manual bladder expression.
- Catheterisation.
- Cystocentesis.
The veterinary surgeon asks you to obtain a free flow urine sample from a dog; why should you collect the sample mid-stream?
A mid-stream sample is less likely to be contaminated with epithelial cells or mucous from the urinary tract.
What preservative is suitable for bacteriology tests on a urine sample?
Boric acid.
What is the normal specific gravity range of urine in dogs and cats?
- Dogs = 1.018-1.045
- Cats = 1.020-1.040
What is the specific gravity of urine measured with?
A refractometer. A hydrometer may also be used, but this is less accurate.
What conditions may be indicated by a high urine specific gravity?
- Dehydration.
- Acute renal failure.
- Shock.
What conditions may be indicated by a low urine specific gravity?
- Increased water intake (polydipsia).
- Diabetes insipidus.
- Pyometra.
- Chronic hepatic dysfunction.
- Chronic renal dysfunction.
What is the normal pH range of urine in dogs and cats?
- Dogs = 5.2-6.8
- Cats = 6-7
Why are dipsticks not ideal for testing urine samples?
- Prone to contamination.
- Can only provide an estimation rather than an accurate result.
- Not reliable for pH readings.
- Very ineffective on stale samples.
What parameters are measured with a Combur 7 Test (BM Test-7)?
- pH.
- Protein.
- Glucose.
- Ketones.
- Urobilinogen.
- Bilirubin.
- Haemoglobin.
List 3 methods of measuring the pH of urine; which is the most reliable?
- Litmus paper.
- Reagent sticks.
- Electrode meter.
The electrode meter is without doubt the most reliable method.
List possible causes of haematuria.
- Cystitis and associated infection/inflammation of the urinary tract.
- Urolithiasis.
- Nephritis.
- Thrombocytopaenia.
- Trauma.
- Bladder masses.
- Drug reactions (e.g. some chemotherapeutic agents).
What is haemoglobinuria?
The presence of lysed blood in the urine.
List possible causes of haemoglobinuria.
- Autoimmune haemolytic anaemia.
- Systemic lupus erythrematosus.
- Leptospirosis.
- Babesiosis.
Urine collected free flow, from manual bladder expression or via catheterisation usually contains a small amount of protein as a result of secretions from the urogenital tract. Protein levels may also rise following parturition or during oestrus. However, true proteinuria is likely to be indicative of a clinical problem. List some causes.
- Nephritis.
- Congestive heart failure.
- Cystitis.
- Urethral inflammation.
- Vaginitis.
Name the 2 main techniques used to examine urine microscopically and state the stain used for each.
- Wet preparation - uses Sedistain (optional).
- Dry preparation - uses Leishman's stain.
List items of interest which may be observed upon the microscopic examination of urine.
- Crystals.
- Casts.
- Mucus threads.
- Spermatozoa.
- Bacteria.
- Funghi.
- Yeasts.
- Epithelial cells.
- Transitional cells.

revision guide

poochunker — Wed, 04 Nov 2009 15:05:26 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by poochunker on 04/11/2009 15:05:26

updates

Obstetrics & Paediatrics - Glossary

Arlo Guthrie — Tue, 21 Apr 2009 11:16:19 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:16:19

Acute phase protein = Protein released during pregnancy which is the basis for commercial pregnancy testing kits. However, these proteins are also released in inflammatory conditions such as pyometra.

Acyclic = Occurring independently of a natural cycle of events. The menstrual cycle is an example.

Agenesis = Failure of a structure to develop properly. Examples are ovarian agenesis and uterine agenesis in the bitch.

Allantoamnion = The inner membrane formed when the membrane of the allantois fuses with the chorion during embryonic development.

Allantois = A membranous sac projecting from the ventral surface of the embryo which receives urine from the foetal kidneys. It eventually helps to form the placenta.

Amnion = The innermost membrane of the embryo which encloses the amniotic fluid.

Anorchia = Complete absence of testes.

Aplasia = Incomplete development of a tissue or organ or absence of growth.

Atresia = Absence of a natural opening. Examples are anal or vaginal atresia.

Breech = Foetus positioned in dorsal, posterior longitudinal presentation. The hind limbs are usually flexed and directed towards the dam's head. This may be a cause of foetal dystocia.

Bulbo-urethral glands = A pair of glands present only in the tom cat which produce a fluid that contributes to the semen.

Caesarean = Surgical operation involving an incision through the abdominal wall and uterus for delivery of the foetus/foetuses if a normal birth is not possible.

Chorio-allantois = The outer membrane formed when the allantois and chorion fuse during embryonic development.

Chorion = The outer layer of the developing embryo; the placenta.

Colostrum = A viscous, yellow fluid representing the accumulated secretions of the mammary glands over the final weeks of pregnancy. This contains immunoglobulins necessary for passive immunity of the foetus.

Congenital defect = A defect present at birth which is not necessarily inherited from ancestry.

Corona radiata = The outer protective layer of the ovum made of small follicular cells.

Corpus luteum = A solid structure developed from the follicle after ovulation which releases the hormones progesterone and relaxin.

Cryptorchidism = Testes retained within the abdomen; may be unilateral or bilateral.

Cystic endometrial hyperplasia = Small cystic lesions which develop in older females in response to progesterone during metoestrus. This may make the uterus more prone to infection and can lead to pyometra.

Dioestrus = Phase of the oestrus cycle following oestrus. In the queen this is represented by mature luteal phase, but in the bitch is often used synonymously with metoestrus (early luteal phase) to reflect the luteal phase of the cycle following standing oestrus.

Dystocia = Difficult birth. See key notes.

Encephalocoele = A congenital defect caused by a failure of the bones of the cranium to fuse. This results in a defect of the skull through which a portion of the brain bulges.

Endometrium = The mucous membrane lining the uterus.

Falciform ligament = The remains of the umbilical vein in an adult; a fat filled structure which runs from the umbilicus to the liver.

Fimbriae = The irregular processes found at the ovarian end of the oviduct.

First fraction = Clear fluid originating from the prostate ejaculated by the male prior to mounting. Its purpose is to flush urine and cellular debris from the urethra.

Follicle stimulating hormone = Hormone produced by the anterior pituitary which controls the maturation of the graafian follicles in the ovary.

Foramen ovale = A hole in the interatrial septum allowing mixing of blood from both sides of the heart. This closes shortly after birth.

Gravid = Pregnant.

Hereditary defect = A defect derived from ancestry. This may be congenital (present at birth) or develop later in life.

Hypocalcaemia = Low blood calcium levels. Also known as puerperal tetany or eclampsia. This is a serious condition that may affect the queen or bitch during pregnancy or lactation.

Hypogonadism = A rare condition resulting in poor development of gonadal tissue due to a primary abnormality in the secretion of pituitary hormones.

Interoestrus = Stage of non-receptivity in the oestrus cycle of the queen. This occurs in the absence of mating or if the mating does not result in ovulation.

Intromission = This follows ejaculation of the first fraction. The male sustains a full erection, mounts the female and his penis enters her vagina.

Lutenising hormone = Hormone produced by the anterior pituitary gland in late anoestrus which initiates the growth of follicles within the ovaries and subsequently causes them to release oestrogen.

Marginal haematoma = Vulval discharge post parturition which is green in the bitch and brown in the queen. It results from the degeneration of the maternal endothelium at the edges of the placenta.

Metoestrus = The early luteal phase of progesterone production.

Micropthalmos = A congenital abnormality in which the eyes are very small. It occurs most often in Pekinese. A hereditary type may occur in Great Danes and Collies.

Misalliance = Unwanted pregnancy.

Monoestrus = One oestrus period in each breeding season. The bitch is monoestrus.

Monorchidism = Describes an animal with a single testicle.

Multigravid = Pregnancy which is not the first.

Multiparous = Several young developing in one uterus.

Myometrium = The muscle tissue of the uterus.

Oestrogen = Hormone produced in the ovary which prepares the genital tract for coitus and reception of the fertilised eggs. (It is also produced in the testis).

Oestrus = Season; heat. Ovulation occurs during this phase of the reproductive cycle.

Orchitis = Inflammation of the testes as a result of trauma or bacterial infection.

Oxytocic = Drug which stimulates uterine contractions. Oxytocin may be given in cases of uterine inertia providing dystocia is not obstructive.

Paraphimosis = Failure to retract the penis into the prepuce.

Parturition = The act of giving birth.

Phimosis = Inability to extrude the penis.

Placenta = Vascular structure inside the gravid uterus which supplies the foetuses with nourishment via the umbilical cord. Post parturition, this is the afterbirth.

Poikilothermic = Body temperature which varies with that of the ambient temperature. Neonates are unable to regulate their own body temperature and are described as poikilothermic.

Polyoestrus = Multiple oestrus cycles within the breeding season. Queens are described as seasonally polyoestrus which means that they have oestrus cycles throughout their breeding season (February to September).

Polytocious = Numerous offspring produced in each litter.

Prepartum Hypothermia = Decline of about 2°C in the bitch's body temperature which precedes the onset of parturition by 24-36 hours. This occurs as a result of a sudden drop is plasma progesterone concentration.

Priapism = Persistent enlargement of the penis in the absence of sexual excitement.

Primigravid = First pregnancy.

Proestrus = The first stage of the reproductive cycle; plasma concentrations of oestrogen increase. The female is receptive to the male but will not allow mating.

Progesterone = Hormone produced by the corpus luteum of the ovary; essential for the maintenance of pregnancy.

Prolactin = Hormone produced by the anterior pituitary which stimulates milk production during late pregnancy and lactation.

Pseudocyesis = False pregnancy. In bitches non-fertile matings result in ovulation without conception during metoestrus.

Puerperium = The return of the reproductive organs to their normal state following pregnancy.

Pyometra = Infection of the uterus. This is a very serious condition. Open pyometra is characterised by a vulval discharge. Bitches must be speyed immediately.

Split oestrus = An endocrinological disease of the bitch; signs of proestrus which do not terminate in ovulation. A normal cycle follows 2-12 weeks later.

Standing oestrus = The bitch is receptive to the dog and stands to be mated.

Tie = The period following ejaculation when the dog and bitch remain in sexual contact. The dog dismounts from the female and turns through 180° with his penis still penetrating the bitch. The two remain back to back for at least 20 minutes and must not be separated. The purpose is to allow the third portion of ejaculate to flush sperm forwards through the cervix and into the uterus.

Uniparous = A single foetus developing in the uterus.

Vestibule = A space or cavity at the entrance to another structure. The vaginal vestibule is caudal to the vagina and continues into the vulva.

Zona pellucida = The glycoprotein inner membrane of the ovum.

Zonary placenta = The band around the middle of the extra-embryonic membranes of the placenta.

Neutering - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:15:34 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:15:34

ANSWERS

If an owner is not intending to breed from a bitch, list 5 advantages of spaying?
- Unwanted puppies are prevented.
- False pregnancy is avoided.
- Pyometra (accumulation of pus within the uterus - a very serious bacterial infection) is avoided.
- The risk of mammary neoplasia is reduced.
- There will be none of the mess and hassle associated with seasons.
What is the medical term for the removal of the uterus and ovaries?
Ovariohysterectomy.
Why is an ovariohysterectomy preferential to an ovariectomy?
An ovariectomy is removal of the ovaries. The uterus is left intact. The main disadvantage of this method is that pyometra remains a risk.
When is the best time to spay a bitch?
Either before her first season (at approximately 6 months of age) or when she is midway between seasons.
Why should a bitch not be spayed during pseudocyesis (false pregnancy)?
It is possible that she may remain psychologically in a state of false pregnancy for the rest of her life.
What alternative to spaying will prevent the occurrence of oestrus?
Medical inhibition of a season by progestogen/androgen compounds. Depot injections may be administered during anoestrus to prevent the next anticipated heat.
List side effects that may arise from the medical inhibition of heat.
- Increased appetite and subsequent weight gain.
- Lethargy.
- Mammary enlargement.
- Coat changes.
- Possible temperament changes.
- The risk of inducing pyometra.
Many owners have reservations about spaying. Give examples of 2 potential disadvantages and how they might be overcome.
- Weight gain - regulate with dietary control.
- Urinary incontinence - this affects only a small percentage of bitches and successful medical treatment is available to treat this condition.
List 3 advantages of cat castration.
- The tendency to roam is reduced.
- Spraying to mark territory is reduced (and the urine smells less pungent).
- The cat is less likely to catch diseases such as feline leukaemia transmitted in blood and saliva and associated with mating and fighting.
List 3 advantages of dog castration.
- Prevention of testicular neoplasms.
- Reduced incidence of prostatic cancer.
- Reduction of excessive libido which may lead to dominance and aggression in some dogs.

Neutering

Arlo Guthrie — Tue, 21 Apr 2009 11:14:48 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:14:48

QUESTIONS

If an owner is not intending to breed from a bitch, list 5 advantages of spaying?
What is the medical term for the removal of the uterus and ovaries?
Why is an ovariohysterectomy preferential to an ovariectomy?
When is the best time to spay a bitch?
Why should a bitch not be spayed during pseudocyesis (false pregnancy)?
What alternative to spaying will prevent the occurrence of oestrus?
List side effects that may arise from the medical inhibition of heat.
Many owners have reservations about spaying. Give examples of 2 potential disadvantages and how they might be overcome.
List 3 advantages of cat castration.
List 3 advantages of dog castration.

The Normal Neonate - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 11:13:56 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:13:56

NORMAL BODY TEMPERATURE - PUPPIES:

Age In Weeks	Temperature Range °C
0-2	34.5-36
2-4	36-37
4 plus	37-38.5

NORMAL BODY TEMPERATURE - KITTENS:

Age In Weeks	Temperature Range °C
0-2	35-36.5
2-4	36.5-37.5
4 plus	37.5-38.7

NORMAL RESPIRATORY RATE - PUPPIES AND KITTENS:

Age	Breaths per Minute
0-24 hrs	8-18
1-35 days	15-35

NORMAL HEART RATE - PUPPIES AND KITTENS:

Age	Beats per Minute
0-24 hrs	120-150
1-35 days	220

NUTRITIONAL REQUIREMENTS:

Species	Kcal per 500g of body weight per day
Puppies	60
Kittens	200

(Orphan formula milk contains approximately 1 kcal/ml)

NORMAL BIRTH WEIGHTS:

Species	Weight in Grams
Toy breeds	100-200
Medium breeds	200-300
Large breeds	400-500
Giant breeds	500-700
Kittens	700 plus

EXPECTED INCREASES IN BODY WEIGHT:

Species	Should double in birth weight within
Puppies	10-12 days
Kittens	14 days

Generally, an increase of 10-15% of birth weight per day in the first week of life is normal, and a 20-25% increase per day thereafter.

Another useful guide is that puppies should gain 2-4g/kg of their anticipated adult weight per day.

Care Of Lactating Dam & Litter - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:12:23 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:12:23

ANSWERS

Define paediatrics.
The branch of medicine relating to the young, including their development and care, and diseases which may affect them.
What is the term used to describe the return of the reproductive tract to its non-pregnant state following parturition?
The puerperium.
What are the 3 main causes of fading puppy/kitten syndrome?
- Dehydration.
- Hypoglycaemia
- Hypothermia.
After parturition, by how much should the dam's food be increased?
- Week 1 - 1.5 x maintenance.
- Week 2 - 2 x maintenance.
- Week 3 plus - 3 x maintenance.
At what age should puppies and kittens first be wormed?
2 and a half to 3 weeks of age.
What type of diet is ideal for nursing queens and bitches and why?
A proprietary growth food. Feeding a high quality complete food will ensure that optimum levels of all nutrient groups are met.
List criteria important to the diet of a lactating queen or bitch.
- The food must be palatable.
- It must provide sufficient energy to meet her increased requirements.
- It must provide optimum levels of all nutrient groups.
- The protein content should be of a high biological value.
At what age may weaning commence?
From 3 weeks, this is a gradual process.
Describe the process of weaning in puppies.
- Weaning begins once the litter's eyes have opened - usually at about 3-4 weeks of age.
- A suitable food designed for growth should be made into a gruel and warmed to body temperature.
- Gradually decrease the amount of water until the puppies are on solids.
- By 5 weeks of age, the pups should be eating 5 meals a day, with the bitch separated from them for short intervals to accustom them to being without her and to feed from the food bowl.
Why should cow's milk not be given to puppies and kittens?
It has a high lactose content which may cause diarrhoea and lead to dehydration.
What signs may indicate that all is not well with the neonates?
- Excessive vocalisation.
- Not gaining weight.
  During the first few weeks of life it is normal for neonates to just eat and sleep.
What criteria are important in raising a healthy litter?
- The health status and nutrition of the dam.
- A warm environment with a suitable nest (neonates are poikilothermic and unable to control their body temperature).
- Early ingestion of colostrum to provide the immunoglobulins necessary for passive immunity.
How can thermoregulation of the litter be controlled?
- Birth should take place in a warm environment.
- Keep the litter dry.
- Provide a well insulated nest box with an additional heat source such as an electric heat pad.
- Ensure that food intake is adequate.
- Encourage huddling which reduces the overall surface area.
  Neonates have very little subcutaneous fat and consequently their insulation is poor. Heat loss is greater in smaller animals since the surface area to body unit weight is greater.
How much more energy (on a per kg basis) do growing puppies require compared to adults?
Twice as much.
Why is food limited feeding considered preferential over free choice feeding for large breed puppies?
Free choice feeding can lead to excessive dietary energy. This may support a growth rate that is too fast for proper skeletal development. In addition to skeletal disorders, a predisposition to juvenile obesity may result.

Care Of Lactating Dam & Litter

Arlo Guthrie — Tue, 21 Apr 2009 11:11:36 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:11:36

QUESTIONS

Define paediatrics.
What is the term used to describe the return of the reproductive tract to its non-pregnant state following parturition?
What are the 3 main causes of fading puppy/kitten syndrome?
After parturition, by how much should the dam's food be increased?
At what age should puppies and kittens first be wormed?
What type of diet is ideal for nursing queens and bitches and why?
List criteria important to the diet of a lactating queen or bitch.
At what age may weaning commence?
Describe the process of weaning in puppies.
Why should cow's milk not be given to puppies and kittens?
What signs may indicate that all is not well with the neonates?
What criteria are important in raising a healthy litter?
How can thermoregulation of the litter be controlled?
How much more energy (on a per kg basis) do growing puppies require compared to adults?
Why is food limited feeding considered preferential over free choice feeding for large breed puppies?

Orphans' Feeding Requirements - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 11:10:38 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:10:38

Orphans' Feeding Requirements - Practical Task

INTRODUCTION
There is no better diet for a neonate than the natural milk of the dam. This is why a foster mother (such as a bitch in pseudo-pregnancy) is the preferred source of nutrition for orphaned neonates. However, it could prove difficult to find a suitable infection-free bitch or queen and therefore it may be necessary to hand rear the litter using milk substitutes. It is vital that the veterinary nurse is able to advise clients accurately since the livelihood of the neonates will be at stake. It may be that you are personally involved in the undertaking of hand rearing in instances such as complications in the dam following Caesarean. In the Practical Examination, you may be required to demonstrate preparation of milk substitutes and show a good knowledge of feeding techniques and quantities to be fed.

In the first few hours after birth, the neonate must receive colostrum. This is a yellow viscous fluid that represents the accumulated secretions of the mammary glands over the final weeks of pregnancy. Colostrum contains high concentrations of immunoglobulins which are necessary for 90% of the new-born's passive immunity (the other 10% is derived transplacentally). Neonates need colostrum within their first few hours since immunoglobulins are large molecules which can only be taken in by pinocytosis. The small intestine ceases to absorb large molecules after a limited period. Milk substitutes do not contain colostrum, therefore it is recommended that 1-5mls of serum is obtained from the dam and injected subcutaneously into the neonate or mixed with the milk substitute and given orally. If this is not possible, deep frozen or freeze-dried colostrum from other dams may be used.
Commercial milk formulas are preferable to home-made milk substitutes since the exact nutritional constituents are known. They are also quicker and easier to prepare. Cimicat for kittens and Welpi for puppies are often recommended and should be made up according to the manufacturer's instructions. Using boiled water to reconstitute the milk can reduce the risk of infection. The milk should be fed at body temperature (37 °C).
If commercial diets are not available, home-made substitutes are acceptable. In an emergency, powdered evaporated cow's milk (made up to double the strength recommended for babies) supplemented with 8g calcium phosphate per litre is suitable for both puppies and kittens. Proprietary growth diets may be blended in a food processor and mixed with milk. Cow's milk alone is unsuitable since it contains 15% less protein than bitches milk, 30% less protein than queen's milk and half the required amount of calcium and phosphorous. Cow's milk contains significantly more lactose which can cause diarrhoea in some puppies and kittens. Other home-made diets include:
- 3 Parts evaporated milk with 1 part water (puppies).
- 1L Full fat cow's milk, 4 egg yolks & 1 tablespoon corn oil (puppies).
- 800mls Cow's milk, 200mls single cream, 1 egg yolk, 6g sterilised bone flour & 4g Citric acid (puppies).
- 500mls Cow's milk, 1 egg yolk, multivitamin drops (e.g. Abidec) & calcium supplementation (kittens).
It is essential that the neonate receives the correct balance of calcium and phosphorous for healthy bone growth. Vitamins A and D are also of great importance. Remember however that over-supplementation can be just as harmful as too little. This is also an important factor in adult diets.
Having established a suitable milk substitute, a feeding regime must be organised. During the first week of life neonates require feeds every 2 hours during the day and every 4 hours at night. At 1-3 weeks of age feeds are reduced to every 4 hours during the day and every 6 hours at night. By the fourth week, feeds should be given at 8 hourly intervals.
There are several methods of administering the milk substitute to the neonate. Syringes are only really suitable in an emergency due to the danger of aspiration pneumonia. Orogastric or nasogastric feeding tubes are convenient but do not allow the puppy or kitten to suckle. Bottles or feeders with a nipple are ideal, but care must be taken to avoid feeding too much too quickly. Again, avoid aspiration. Hand feeding is a messy business, and if the neonate becomes wet with milk, ensure that it is cleaned, dry and warm before replacing in the incubator. It is advisable to keep the neonate wrapped in a warm towel during feeds and sensible for the nurse to wear a protective apron.
Puppies require 60 kcal/500g body weight per day, while kittens require 200 kcal/500g per day. Milk substitutes contain approximately 1 kcal/ml. Neonates will stop feeding when they are full. After a meal, the abdomen should feel enlarged but not distended. Never feed more than 50ml/kg in one feed if using an orogastric or nasogastric feeding tube. Puppies and kittens should gain 2-4g/kg/day of their anticipated adult body weight. Healthy neonates spend most of their time eating and sleeping. A very vocal puppy or kitten is likely to be hungry, cold or both and requires immediate attention. After a feed, gently wipe the genital area with warm wet cotton wool to simulate the action of the dam's tongue. This stimulates urination and defecation and is a very important aspect of neonate care.

Orphans' Feeding Requirements

Arlo Guthrie — Tue, 21 Apr 2009 11:10:03 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:10:03

In the first few hours after birth, the neonate must receive colostrum. This is a yellow viscous fluid that represents the accumulated secretions of the mammary glands over the final weeks of pregnancy. Colostrum contains high concentrations of immunoglobulins which are necessary for 90% of the new-born's passive immunity (the other 10% is derived transplacentally). Neonates need colostrum within their first few hours since immunoglobulins are large molecules which can only be taken in by pinocytosis. The small intestine ceases to absorb large molecules after a limited period. Milk substitutes do not contain colostrum, therefore it is recommended that 1-5mls of serum is obtained from the dam and injected subcutaneously into the neonate or mixed with the milk substitute and given orally. If this is not possible, deep frozen or freeze-dried colostrum from other dams may be used.
Commercial milk formulas are preferable to home-made milk substitutes since the exact nutritional constituents are known. They are also quicker and easier to prepare. Cimicat for kittens and Welpi for puppies are often recommended and should be made up according to the manufacturer's instructions. Using boiled water to reconstitute the milk can reduce the risk of infection. The milk should be fed at body temperature (37 °C).
If commercial diets are not available, home-made substitutes are acceptable. In an emergency, powdered evaporated cow's milk (made up to double the strength recommended for babies) supplemented with 8g calcium phosphate per litre is suitable for both puppies and kittens. Proprietary growth diets may be blended in a food processor and mixed with milk. Cow's milk alone is unsuitable since it contains 15% less protein than bitches milk, 30% less protein than queen's milk and half the required amount of calcium and phosphorous. Cow's milk contains significantly more lactose which can cause diarrhoea in some puppies and kittens. Other home-made diets include:
- 3 Parts evaporated milk with 1 part water (puppies).
- 1L Full fat cow's milk, 4 egg yolks & 1 tablespoon corn oil (puppies).
- 800mls Cow's milk, 200mls single cream, 1 egg yolk, 6g sterilised bone flour & 4g Citric acid (puppies).
- 500mls Cow's milk, 1 egg yolk, multivitamin drops (e.g. Abidec) & calcium supplementation (kittens).
It is essential that the neonate receives the correct balance of calcium and phosphorous for healthy bone growth. Vitamins A and D are also of great importance. Remember however that over-supplementation can be just as harmful as too little. This is also an important factor in adult diets.
Having established a suitable milk substitute, a feeding regime must be organised. During the first week of life neonates require feeds every 2 hours during the day and every 4 hours at night. At 1-3 weeks of age feeds are reduced to every 4 hours during the day and every 6 hours at night. By the fourth week, feeds should be given at 8 hourly intervals.
There are several methods of administering the milk substitute to the neonate. Syringes are only really suitable in an emergency due to the danger of aspiration pneumonia. Orogastric or nasogastric feeding tubes are convenient but do not allow the puppy or kitten to suckle. Bottles or feeders with a nipple are ideal, but care must be taken to avoid feeding too much too quickly. Again, avoid aspiration. Hand feeding is a messy business, and if the neonate becomes wet with milk, ensure that it is cleaned, dry and warm before replacing in the incubator. It is advisable to keep the neonate wrapped in a warm towel during feeds and sensible for the nurse to wear a protective apron.
Puppies require 60 kcal/500g body weight per day, while kittens require 200 kcal/500g per day. Milk substitutes contain approximately 1 kcal/ml. Neonates will stop feeding when they are full. After a meal, the abdomen should feel enlarged but not distended. Never feed more than 50ml/kg in one feed if using an orogastric or nasogastric feeding tube. Puppies and kittens should gain 2-4g/kg/day of their anticipated adult body weight. Healthy neonates spend most of their time eating and sleeping. A very vocal puppy or kitten is likely to be hungry, cold or both and requires immediate attention. After a feed, gently wipe the genital area with warm wet cotton wool to simulate the action of the dam's tongue. This stimulates urination and defecation and is a very important aspect of neonate care.

Orphaned Neonates - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:08:52 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:08:52

Orphaned Neonates - Answers

ANSWERS

What is the alternative to hand rearing?
Finding a suitable foster mother, either a bitch with her own litter or a bitch in pseudocyesis.
Why is a foster mother more beneficial to an orphan than hand rearing?
- It is closer to a natural upbringing and therefore less stressful.
- An orphan may develop significant psychological problems due to lack of contact with a mother and litter mates.
List behavioural problems that may manifest in hand reared orphans in later life.
- Fear of their own species.
- Aggression to their own species.
- Excessive human orientation.
- Sexual attention directed at humans.
- Over-dependence on humans leading to separation anxiety.
Why is colostrum so important?
It contains immunoglobulins necessary for 90% of the neonate's passive immunity.
If an orphan has not received colostrum from the dam, what alternative source may be used?
Deep frozen or freeze-dried colostrum from other dams.
Why must the neonate receive colostrum within the first few hours after birth? Immunoglobulins are large molecules which can only be taken in by pinocytosis. The small intestine ceases to absorb large molecules after a limited period.
Why are commercial milk formulas preferable over home-made milk substitutes?
- They are nutritionally balanced.
- They are easier to prepare.
How frequently should an orphaned neonate be fed during the first week of life?
Every 2 hours during the day, and every 4 hours at night.
Why is the provision of a warm environment essential in the hand rearing of an orphan?
Neonates are poikilothermic and unable to regulate their own body temperature. An orphan will have no mother or littermates to snuggle up against to keep warm, therefore a suitable heat source, clean dry bedding and a warm ambient temperature are vital.
In addition to feeding and providing warmth, what other aspects of nursing care are beneficial to an orphan?
- Stimulation and plenty of TLC.
- Prevention of infection - the orphan should be housed well away from any infectious animals and barrier nursing carried out.
- Keeping the orphan clean and dry.
- Stimulation of urination and defecation by gently wiping the genital area with wet cotton wool.
- Early socialisation with other humans and animals.

Orphaned Neonates - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:08:28 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:08:28

ANSWERS

What is the alternative to hand rearing?
Finding a suitable foster mother, either a bitch with her own litter or a bitch in pseudocyesis.
Why is a foster mother more beneficial to an orphan than hand rearing?
- It is closer to a natural upbringing and therefore less stressful.
- An orphan may develop significant psychological problems due to lack of contact with a mother and litter mates.
List behavioural problems that may manifest in hand reared orphans in later life.
- Fear of their own species.
- Aggression to their own species.
- Excessive human orientation.
- Sexual attention directed at humans.
- Over-dependence on humans leading to separation anxiety.
Why is colostrum so important?
It contains immunoglobulins necessary for 90% of the neonate's passive immunity.
If an orphan has not received colostrum from the dam, what alternative source may be used?
Deep frozen or freeze-dried colostrum from other dams.
Why must the neonate receive colostrum within the first few hours after birth? Immunoglobulins are large molecules which can only be taken in by pinocytosis. The small intestine ceases to absorb large molecules after a limited period.
Why are commercial milk formulas preferable over home-made milk substitutes?
- They are nutritionally balanced.
- They are easier to prepare.
How frequently should an orphaned neonate be fed during the first week of life?
Every 2 hours during the day, and every 4 hours at night.
Why is the provision of a warm environment essential in the hand rearing of an orphan?
Neonates are poikilothermic and unable to regulate their own body temperature. An orphan will have no mother or littermates to snuggle up against to keep warm, therefore a suitable heat source, clean dry bedding and a warm ambient temperature are vital.
In addition to feeding and providing warmth, what other aspects of nursing care are beneficial to an orphan?
- Stimulation and plenty of TLC.
- Prevention of infection - the orphan should be housed well away from any infectious animals and barrier nursing carried out.
- Keeping the orphan clean and dry.
- Stimulation of urination and defecation by gently wiping the genital area with wet cotton wool.
- Early socialisation with other humans and animals.

Orphaned Neonates

Arlo Guthrie — Tue, 21 Apr 2009 11:08:05 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:08:05

QUESTIONS

What is the alternative to hand rearing?
Why is a foster mother more beneficial to an orphan than hand rearing?
List behavioural problems that may manifest in hand reared orphans in later life.
Why is colostrum so important?
If an orphan has not received colostrum from the dam, what alternative source may be used?
Why must the neonate receive colostrum within the first few hours after birth?
Why are commercial milk formulas preferable over home-made milk substitutes?
How frequently should an orphaned neonate be fed during the first week of life?
Why is the provision of a warm environment essential in the hand rearing of an orphan?
In addition to feeding and providing warmth, what other aspects of nursing care are beneficial to an orphan?

Revive Neonate Post Caesarian - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 11:07:03 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:07:03

It is essential that a veterinary nurse is familiar with the practical knowledge required in order to revive a neonate following birth by Caesarean section, since survival of the new-born is dependent on the rapid onset of spontaneous respiration. In the Practical Examination you may be presented with a soft toy or beanbag representing the neonate and asked to demonstrate how you would perform resuscitation.

As with all emergencies; remember the first priority is the patient's airway. Holding the neonate in a warm towel, clear the mouth, nose and pharynx of any attached foetal membrane, fluid and mucus. Using your fingers is the easiest method and does not require any equipment, although a simple suction device such as a syringe may also be utilised.
Next hold the neonate with the head lower than the hind limbs and supporting the head with fore-finger and thumb, swing from side to side or up and down. This will dislodge any fluid that may have accumulated lower down in the respiratory tract. Gently use your fingers to remove.
Briskly rub the chest of the neonate. This provides warmth and helps to dry the new-born in addition to stimulating respiration.
If the neonate is hypoxic, administer oxygen via a mask. In addition, blowing gently into the mouth and nostrils may encourage respiration.
Neonates are more resistant to hypoxia than adults, and natural methods should be used to stimulate the respiratory system during the first minute. If apnoea persists for more than one minute, commence artificial respiration with external cardiac massage (closed chest resuscitation) if required. Massage the heart by compressing the ribs at a rate of 80-100 compressions per minute between thumb and forefinger. Deliver 2-3 lung inflations for every 15 chest wall compressions.
Dopamine (Dopram drops) may be used if myocardial depression is present. Place one drop on the neonate's tongue and continue resuscitation.
If normal respiration is not present after 2-3 minutes, the neonate's chances of survival are poor. If normal spontaneous respiration results, place the neonate in an oxygen rich incubator at 30°C. The neonate may be dried with a hair drier, but take care not to overheat. Remember that new-born puppies and kittens are poikilothermic and are unable to regulate their own body temperature; this means that their body temperature varies with the ambient temperature. Try to provide humidification to the area.
Monitor respiratory rate, heart rate and mucous membrane colour.

Dystocia - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 11:05:49 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:05:49

Type	Cause
Primary uterine inertia	Poor condition of uterine musculature in old, obese or debilitated dams
	Over-stretching of uterus due to large litter size
	Poor stimulus for parturition if very small litter size
	Poor stimulus for parturition if low plasma calcium concentrations
Secondary uterine inertia	Uterine exhaustion after contractions have started
	Causative factors may be as for primary uterine inertia
	Obstructive dystocia such as deformity of the pelvic bones or soft tissue defects

Type	Cause
Foetal oversize	Small litter of large foetuses
Breed conformation	Large head size (eg. Bull Dog)
Developmental defect	Hydrocephalus or Oedema
Abnormal foetal alignment	Faulty presentation, position or posture

Caesarean Section - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:04:20 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:04:20

ANSWERS

What is dystocia?
Difficult birth; non-productive straining by the dam for longer than an hour is cause for concern.
What developmental defects may result in foetal dystocia?
- Hydrocephalus.
- Oedema.
List key points crucial in the recognition of dystocia.
- Know what is normal.
- Establish the stage of pregnancy.
- Establish relevant history and what has already been done by the owner.
- Regularly monitor rectal temperature in order to detect the prepartum hypothermia.
- Establish the time that straining commenced, the character of the straining efforts and whether any foetuses have been born.
- Unproductive straining for longer than one hour is always cause for concern, and a veterinary surgeon should be contacted immediately.
Give an example of a breed of dog that is commonly delivered by Caesarean and why?
The bulldog, due to its large head size.
Define presentation, position and posture (terms used to describe the orientation of the foetus).
- Presentation - the direction of the long axis of the foetus in relation to the long axis of the dam.
- Position - describes the dorsal axis of the foetus in relation to that of the dam and the degree of rotation (most species are born in the dorsal position).
- Posture - describes the orientation of the head and legs of the foetus.
What is meant by the "breech position"?
The foetus is delivered in a posterior longitudinal presentation, usually in a dorsal position with the hind limbs flexed.
Why is general anaesthesia for a Caesarean high risk?
- The bitch or queen may have been fed.
- The animal may be debilitated following straining.
- Respiratory embarrassment due to the pressure of the gravid uterus on the diaphragm.
- Beware with nitrous oxide due to the second gas effect.
- Hypotension due to compression of the vena cava when the animal is in the supine position.
List 3 possible reasons for vomiting during recovery from anaesthesia following Caesarean surgery.
- The bitch or queen was not starved.
- Increased gastric emptying time during labour.
- Increased intra-gastric pressure during pregnancy.
What complications may arise following Caesarean section?
- Wound interference by the neonates suckling.
- Problems with litter acceptance and subsequent reduction in colostrum intake.
- Anaesthetic risk to the dam and/or neonates.
- Risk of uterine rupture during surgery.
- Post-operative risks such as infection and wound breakdown.
- The dam may crush the litter if she is not able to co-ordinate herself properly following the anaesthetic.
Why is Propofol an ideal induction agent for anaesthesia of a bitch or queen undergoing a Caesarean?
Animals recovery rapidly once administration of the volatile agent is ceased.
What are the 2 possible reasons for a Caesarean operation?
- For the relief of dystocia.
- Electively if concern regarding feto-maternal disproportion.
How can the dam be encouraged to accept her litter following a Caesarean?
Cover the neonates heads with her milk to encourage her to lick them. Take care not to allow the neonates to become too wet since this may cause hypothermia.

Caesarean Section

Arlo Guthrie — Tue, 21 Apr 2009 11:03:35 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:03:35

QUESTIONS

What is dystocia?
What developmental defects may result in foetal dystocia?
List key points crucial in the recognition of dystocia.
Give an example of a breed of dog that is commonly delivered by Caesarean and why?
Define presentation, position and posture (terms used to describe the orientation of the foetus).
What is meant by the "breech position"?
Why is general anaesthesia for a Caesarean high risk?
List 3 possible reasons for vomiting during recovery from anaesthesia following Caesarean surgery.
What complications may arise following Caesarean section?
Why is Propofol an ideal induction agent for anaesthesia of a bitch or queen undergoing a Caesarean?
What are the 2 possible reasons for a Caesarean operation?
How can the dam be encouraged to accept her litter following a Caesarean?

Care During Parturition & Pregnancy - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:02:11 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:02:11

ANSWERS

Define obstetrics.
The branch of medicine relating to pregnancy, parturition (labour) and the puerperium (return of the dam's reproductive system to its non-pregnant state).
What is the average gestation period of a bitch?
63 days.
What is the average gestation period of a queen?
64 days.
List 6 techniques for pregnancy diagnosis and the most suitable time for their performance.
- Abdominal palpation - 28 days after mating.
- Auscultation of foetal heart beats - late pregnancy.
- Radiography - from day 30.
- Hormone tests (Relaxin) - from day 25 (but no commercial assay available in the UK).
- Acute phase protein test - from day 30.
- Ultrasound - from day 16, but prudent to wait until day 28.
When does mammary development become obvious in the pregnant bitch?
From day 40.
When should the food intake of a pregnant bitch be increased?
Day 35.
By what percentage should the amount of the food fed to the dam have been increased by the time she is due to whelp?
15-25%.
Why might it be sensible to feed the dam smaller more frequent meals during the last 10 days of pregnancy?
In order to compensate for the reduced space in the abdominal cavity.
What is a suitable diet for a pregnant bitch and why?
Proprietary growth formula with increased protein of a high biological value and decreased fibre.
Bitches and queens are polytocious; what does this mean?
They produce numerous offspring in each litter.
What types of wormers are safe to use during pregnancy?
Benzinimadozoles; but always refer to the manufacturer's data sheet prior to use.
List 4 clinical signs of pregnancy.
- Increase in body weight.
- Abdominal enlargement.
- Mammary gland enlargement and redness.
- Serous fluid from the mammary glands from day 40 (and milk from day 50).
Give 2 physiological signs of pregnancy.
- Normochromic, normocytic anaemia.
- Reduction of packed cell volume (PCV).
What is hypocalcaemia?
Low blood calcium levels.
What drug is used to treat hypocalcaemia?
Calcium borogluconate.
Give 2 other names by which hypocalcaemia may be known.
- Puerperal tetany.
- Eclampsia.
At parturition, the marginal haematoma results in a vulval discharge; what colour is this in bitches and in queens?
- Bitches - green.
- Queens - brown.
What is the ideal temperature for a whelping box?
30°C.
What is prepartum hypothermia and when may this be detected?
A decrease of approximately 2°C in the bitch's body temperature as a result of a sudden reduction in plasma progesterone. It precedes the onset of parturition by 24-36 hours.
List the signs of first stage parturition.
- Cervix dilates.
- Milky discharge produced from the mammary glands.
- Allantoic fluid discharge from the vulva (from the ruptured placenta).
- Nesting.
- Panting.
- Vomiting.
- Anorexia.
- Onset of uterine contractions.
  Please refer to Key Notes: Parturition.
When would intervention be necessary by a veterinary surgeon during second stage parturition?
If unproductive straining is observed in the bitch for longer than 1 hour.
How would you stimulate straining during parturition?
Apply gentle pressure with a finger to the roof of the vagina.
How would you assist delivery during parturition if the foetus were in the breech position?
Only apply traction if the foetus is presented normally. In this case you would alert the veterinary surgeon. Never apply traction to the feet, as these are easily damaged.
What is meant by dystocia?
A difficult birth.
Please refer to Module Six for Key Notes: Dystocia.

Care During Parturition & Pregnancy

Arlo Guthrie — Tue, 21 Apr 2009 11:01:20 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:01:20

QUESTIONS

Define obstetrics.
What is the average gestation period of a bitch?
What is the average gestation period of a queen?
List 6 techniques for pregnancy diagnosis and the most suitable time for their performance.
When does mammary development become obvious in the pregnant bitch?
When should the food intake of a pregnant bitch be increased?
By what percentage should the amount of the food fed to the dam have been increased by the time she is due to whelp?
Why might it be sensible to feed the dam smaller more frequent meals during the last 10 days of pregnancy?
What is a suitable diet for a pregnant bitch and why?
Bitches and queens are polytocious; what does this mean?
What types of wormers are safe to use during pregnancy?
List 4 clinical signs of pregnancy.
Give 2 physiological signs of pregnancy.
What is hypocalcaemia?
What drug is used to treat hypocalcaemia?
Give 2 other names by which hypocalcaemia may be known.
At parturition, the marginal haematoma results in a vulval discharge; what colour is this in bitches and in queens?
What is the ideal temperature for a whelping box?
What is prepartum hypothermia and when may this be detected?
List the signs of first stage parturition.
When would intervention be necessary by a veterinary surgeon during second stage parturition?
How would you stimulate straining during parturition?
How would you assist delivery during parturition if the foetus were in the breech position?
What is meant by dystocia?

Foetal Development - Answers

Arlo Guthrie — Tue, 21 Apr 2009 11:00:30 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 12:00:30

ANSWERS

Give 2 names by which the uterine tube might also be known.
- Fallopian tube.
- Oviduct.
What is an oocyte?
An immature egg cell or ovum in the ovary.
What does the double protective layer that surrounds the ovum following its release from the ovary consist of?
- Zona pellucida - the glycoprotein inner layer.
- Corona radiata - the outer layer comprising follicular cells.
Where does fertilisation take place?
The Fallopian tube.
What is the fertilisation reaction?
This occurs once the first sperm has penetrated the zona pellucida, and prevents any other spermatozoa from entering the ovum.
What is a zygote?
The fertilised ovum.
When does the zygote become a morula?
Once the cells have divided to form a solid ball of cells.
What is the mass towards one end of the morula known as?
The inner cell mass.
What are the cells lining the cavity of the morula known as?
The trophoblast.
What are the 3 germ cell layers and what parts of the neonate's body will the eventually form?
- Ectoderm - skin and nervous system.
- Mesoderm - musculo-skeletal system and internal organs.
- Endoderm - gastro-intestinal tract and visceral structures.
When and where does implantation take place?
11-16 days in the queen, and 14-20 days after ovulation in the bitch. Implantation occurs at the wall of the uterus.
Name the 4 extra-embryonic membranes and their functions.
- Yolk sac - primitive gut tube.
- Chorion - the outer membrane of the embryo.
- Amnion - the inner membrane of the embryo.
- Allantois - removes urine from the foetal bladder.
Describe the formation of the water bag.
The fusion of the chorion and allantois to form the chorioallantois (the outer membrane).
Describe the formation of the slime bag.
The fusion of the allantois and the amnion to form the allantoamnion (the inner membrane).
What nutritional source does the marginal haematoma provide?
Iron.
At parturition, the marginal haematoma results in a vulval discharge - what colour is this in bitches and in queens?
- Bitches - green.
- Queens - brown.
How is the foetal circulation different to that of a mammal after birth?
- A single umbilical vein brings blood from the foetus to the placenta.
- 2 Umbilical arteries carry blood back from the placenta.
- The lungs are collapsed and oxygen is provided via the umbilical vein.
What is the falciform ligament?
The remains of the umbilical vein in an adult.
Describe the features present in a developing embryo by the end of week 4.
- Eyes are pigmented.
- The external ear is represented by a ridge of skin.
- The limbs are cylindrical with an indication of paw shape.
- The embryo measures approximately 20mm in length.
Describe the features present in a developing foetus by the end of week 6.
- Scrotal and vulval tissues are prominent.
- The eyelids are fused.
- The digits are widely spread with formed claws.
- Hair follicles are present.
- There is slight ossification of the skeleton.
- The foetus measures approximately 60mm in length.

Foetal Development

Arlo Guthrie — Tue, 21 Apr 2009 10:59:52 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:59:52

QUESTIONS

Give 2 names by which the uterine tube might also be known.
What is an oocyte?
What does the double protective layer that surrounds the ovum following its release from the ovary consist of?
Where does fertilisation take place?
What is the fertilisation reaction?
What is a zygote?
When does the zygote become a morula?
What is the mass towards one end of the morula known as?
What are the cells lining the cavity of the morula known as?
What are the 3 germ cell layers and what parts of the neonate's body will they eventually form?
When and where does implantation take place?
Name the 4 extra-embryonic membranes and their functions.
Describe the formation of the water bag.
Describe the formation of the slime bag.
What nutritional source does the marginal haematoma provide?
At parturition, the marginal haematoma results in a vulval discharge - what colour is this in bitches and in queens?
How is the foetal circulation different to that of a mammal after birth?
What is the falciform ligament?
Describe the features present in a developing embryo by the end of week 4.
Describe the features present in a developing foetus by the end of week 6.

Mating - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:59:02 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:59:02

ANSWERS

At what age do dogs and bitches reach puberty?
6-12 months of age in dogs, and 12-14 months in bitches (although this can be any time from 6 months). Generally, large breeds tend to reach puberty later.
At what age does the fertility of the decline?
7 years of age.
What is spermatogenesis?
The production of spermatozoa. This commences at approximately 5 months of age in both dogs and toms.
What is the function of the cells of Leydig?
Testosterone production.
From which endocrine gland is lutenising hormone produced, and what is its function?
The anterior pituitary. It stimulates the production of testosterone.
What is meant by a "gonadotrophin"?
Any hormone having a stimulating effect on the gonads.
What is the function of follicle stimulating hormone (FSH) in the male?
This increases spermatogenesis via the Sertoli cells.
What is the function of the Sertoli cells?
Production of oestrogen and nutritive fluid for the sperm.
What is the function of gonadotrophin releasing hormone?
Mediation of the negative feedback of testosterone upon the release of follicle stimulating hormone and lutenising hormone.
What is meant by "hypogonadism"?
A rare condition where poor development of the gonadal tissue results from a primary abnormality in the secretion of pituitary hormones.
What is meant by "anorchia"?
Complete absence of testes.
What is the difference between cryptorchidism and monorchidism?
Cryptorchidism means that one or both of the testes are retained within the abdomen, whilst monorchidism means that an animal possesses only one testicle.
What term describes inflammation of the testes?
Orchitis.
What is the term that describes failure to retract the penis into the prepuce?
Paraphimosis.
What is meant by "priapism"?
Persistent enlargement of the penis in the absence of sexual excitement.
What is meant by "phimosis"?
Inability to extrude the penis due to an abnormally small preputial orifice.
What is the "first fraction", and what is its function?
A small volume of clear fluid from the prostate of the male ejaculated prior to mounting. Its function is to clear the urethra of cellular debris and urine.
Describe intromission.
The dog achieves a full erection, enters the bitch and ejaculates the second fraction.
What is the purpose of "the tie" and how long does this last?
The tie enables the third fraction of ejaculate to flush sperm through the cervix and into the uterus. It lasts from 10-60 minutes, the average being 20 minutes.
Which accessory glands are present in the tom but not in the dog?
The bulbourethral glands, which contribute to seminal fluid production.
What fraction of ejaculate is used in the assessment of fertility?
The second fraction.
What stains are suitable for the microscopic examination of spermatozoa?
Eosin and Nigrosin. In dead sperm, the acrosome (head) is detached and stained pink. In live sperm, the acrosome is attached and remains unstained.
By which method of cell division do spermatozoa multiply?
Meiosis.
Where are the sperms stored?
The epididymis.
Give 2 other terms for the deferent duct.
- Vas deferens.
- Ductus deferens.
  The deferent ducts connect the epididymis to the urethra.
Why are multiple matings more likely to result in ovulation?
More lutenising hormone is released.
What 2 natural factors increase the likelihood of conception?
- The relatively long period of fertility of the ova.
- Spermatozoa can survive for long periods within the female reproductive tract.
In addition to clinical assessment, name 2 further methods of determination of the optimum time for mating.
- Measurement of vaginal plasma concentration (Pre-mate Test).
- Vaginal cytology.
Why might the apparent length of pregnancy, assessed from the time of mating vary from between 56 and 72 days?
An early mating produces an apparently longer pregnancy, since spermatozoa survive within the female tract until ovulation or egg maturation. A late mating produces an apparently shorter pregnancy, since the eggs are waiting to be fertilised some time after ovulation.
Upon what days of heat is it recommended that a bitch is mated?
Day 11 & day 13.
What is meant by "misalliance"?
An unwanted pregnancy.
If a client wishes to breed from more than 2 bitches, a licence is required. Which legislation governs this?
The Breeding of Dogs Act 1973.
List 6 factors that ought to be taken into account by an owner prior to breeding.
- Temperament.
- Conformation.
- Space.
- Time.
- Money.
- Market.
A client wishes to use his 3 year old Staffordshire bull terrier as a stud dog; what advice would you give him?
- Bring the dog to the surgery for a thorough health check, in particular to assess the animal for congenital or hereditary defects such as cataracts, cryptorchidism and over-shot or under-shot jaws.
- Ensure that the dog is wormed and vaccinated prior to mating.
- Suggest that the owner purchase a book on dog breeding if he is inexperienced.
- Recommend that he contact the Kennel Club to locate a suitable bitch - she should be of good conformation, temperament and experienced.
- Never interfere with "the tie".
- Suggest that he contact the surgery in the event of any further queries.

Mating

Arlo Guthrie — Tue, 21 Apr 2009 10:58:21 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:58:21

QUESTIONS

At what age do dogs and bitches reach puberty?
At what age does the fertility of the decline?
What is spermatogenesis?
What is the function of the cells of Leydig?
From which endocrine gland is lutenising hormone produced, and what is its function?
What is meant by a "gonadotrophin"?
What is the function of follicle stimulating hormone (FSH) in the male?
What is the function of the Sertoli cells?
What is the function of gonadotrophin releasing hormone?
What is meant by "hypogonadism"?
What is meant by "anorchia"?
What is the difference between cryptorchidism and monorchidism?
What term describes inflammation of the testes?
What is the term that describes failure to retract the penis into the prepuce?
What is meant by "priapism"?
What is meant by "phimosis"?
What is the "first fraction", and what is its function?
Describe intromission.
What is the purpose of "the tie" and how long does this last?
Which accessory glands are present in the tom but not in the dog?
What fraction of ejaculate is used in the assessment of fertility?
What stains are suitable for the microscopic examination of spermatozoa?
By which method of cell division do spermatozoa multiply?
Where are the sperms stored?
Give 2 other terms for the deferent duct.
Why are multiple matings more likely to result in ovulation?
What 2 natural factors increase the likelihood of conception?
In addition to clinical assessment, name 2 further methods of determination of the optimum time for mating.
Why might the apparent length of pregnancy, assessed from the time of mating vary from between 56 and 72 days?
Upon what days of heat is it recommended that a bitch is mated?
What is meant by "misalliance"?
If a client wishes to breed from more than 2 bitches, a licence is required. Which legislation governs this?
List 6 factors that ought to be taken into account by an owner prior to breeding.
A client wishes to use his 3 year old Staffordshire bull terrier as a stud dog; what advice would you give him?

Heat - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:57:33 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:57:33

ANSWERS

During which months are queens (except those kept exclusively indoors) not receptive to toms (in the UK)?
December & January.
Queens are described as "seasonally polyoestrus"; what does this mean?
Having multiple oestrus cycles during the breeding season (ie. February to November).
Bitches are monoestrus; what does this mean?
Having only one oestrus cycle in each breeding season.
The bitch is a spontaneous ovulator; what does this mean?
Ovulation occurs whether the bitch is mated or not.
The queen is an induced ovulator; what does this mean?
Ovulation occurs only if the queen is mated (or if she is artificially stimulated).
How long is proestrus in the bitch?
9-10 days.
How long is oestrus in the bitch?
7-10 days.
In what way is the vulval discharge produced in proestrus different to that seen in oestrus?
A blood stained mucous discharge is seen in proestrus, while a clear amber discharge is seen in oestrus.
What hormones are involved in proestrus, and what are their functions?
- Follicle stimulating hormone (FSH) is released from the anterior pituitary - stimulates maturation of the ovarian follicles in the ovary.
- Oestradiol is produced by the cells of the wall of the developing ovarian follicles - prepares the external genitalia and genital tract for coitus and reception of the fertilised eggs.
If a bitch is not mated, or a mating is infertile; why is pseudocyesis (false pregnancy) common?
The corpora lutea form and produce progesterone necessary for the maintenance of pregnancy. The corpora lutea are established regardless of whether a bitch has been mated.
What is meant by "anoestrus"?
A period of rest until the next season.
What is meant by "interoestrus"?
This is the stage of non-receptivity in the queen in the absence of mating, or if mating has not resulted in ovulation. This lasts 3-14 days, after which time the queen will return to proestrus.
What is the term that describes the absence of cyclical activity during lactation?
Lactational anoestrus.
A client telephones the surgery requesting advice regarding his Labrador bitch. She is 6 months old, and the client would like to breed from her in the future, but not during her first season. List all the useful information you would offer.
- The bitch may come into season at anytime from now, at 6 months it is unlikely but possible. The first season may be delayed however and not occur until the bitch is 18 months old. Advise that the whole season comprises several stages and will last approximately 3 weeks.
- Advise the client of the signs of a season, primarily a blood stained mucous discharge during proestrus, and clear amber fluid during oestrus. Also vocalising, and interest in males.
- Warn the client of the symptoms of pyometra, namely a prolonged enlargement of the vulva, prolonged vaginal discharge, anorexia, polydipsia and depression.
- Suggest that the bitch be exercised on the leash away from areas where other dogs are out and about. The client may have control of the bitch, but an entire male will be very difficult to evict!
- If the bitch is left to exercise in the garden, ensure that it is escape proof!
- Advise that seasons can be messy and that is sensible to invest in easily washable bedding such as Vetbed. Products such as Mikki disposable knickers for bitches are available!
- Warn the client of the symptoms of false pregnancy; predominantly nesting, a very close attachment to a toy and enlarged nipples.
- Reassure the client that in the event of an unwanted mating, help is at hand! The bitch has the equivalent of the morning after pill in the form of a series of injections such as Mesalin. This should be given as soon as possible after the event.
- Long term advice should include the recommendation that the bitch is hip scored at 12 months of age on the BVA/Kennel Club Scheme. In addition, if the client has not bred from a bitch before, they ought to purchase a good book on the subject beforehand and consult the Kennel Club in order to find a suitable sire.
- Recommend that they telephone the surgery at once in the event of any further queries.

Heat

Arlo Guthrie — Tue, 21 Apr 2009 10:56:51 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:56:51

QUESTIONS

During which months are queens (except those kept exclusively indoors) not receptive to toms (in the UK)?
Queens are described as "seasonally polyoestrus"; what does this mean?
Bitches are monoestrus; what does this mean?
The bitch is a spontaneous ovulator; what does this mean?
The queen is an induced ovulator; what does this mean?
How long is proestrus in the bitch?
How long is oestrus in the bitch?
In what way is the vulval discharge produced in proestrus different to that seen in oestrus?
What hormones are involved in proestrus, and what are their functions?
If a bitch is not mated, or a mating is infertile; why is pseudocyesis (false pregnancy) common?
What is meant by "anoestrus"?
What is meant by "interoestrus"?
What is the term that describes the absence of cyclical activity during lactation?
A client telephones the surgery requesting advice regarding his Labrador bitch. She is 6 months old, and the client would like to breed from her in the future, but not during her first season. List all the useful information you would offer.

Congenital & Hereditary Diseases - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:56:10 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:56:10

ANSWERS

What is a congenital defect?
A physical defect present at birth. Congenital defects may occur as a result of trauma to the foetus during pregnancy or they may be inherited.
What is a hereditary defect?
A physical defect derived from ancestry (ie. inherited). Hereditary defects may be present at birth (congenital) or may develop later in life (acquired).
Give 4 examples of congenital defects.
- Cerebellar hyperplasia.
- Umbilical hernia.
- Cleft palate.
- Polydactylism (extra toe/s).
Give 4 examples of hereditary defects.
- Deafness in white cats.
- Cataracts.
- Entropion.
- Cervical spondylosis.
List 4 conditions which may be both congenital and hereditary.
- Cleft palate.
- Progressive retinal atrophy.
- Luxating patella.
- Hydrocephalus.
Give an example of a breed of dog that is predisposed to entropion?
The Shar Pei.
Give an example of a defect which may be both congenital and hereditary.
Hip dysplasia.
List 4 breeds of dog predisposed to hip dysplasia.
- German Shepherd.
- Golden Retriever.
- Labrador Retriever.
- Rottweiler.
Name the organisations that run a screening programme to help reduce the risk of breeding from dogs affected with hip dysplasia.
- The British Veterinary Association (BVA).
- The Kennel Club.
How frequently should a breeding bitch be examined under the BVA eye scheme?
Every 12 months.
Give 2 examples of hereditary defects commonly seen in Border collies.
- Progressive retinal atrophy (PRA).
- Collie eye anomaly.
State the breed of dog predisposed to entropion, PRA and familial nephropathy.
The Cocker spaniel.
In addition to genetic predisposition, what other factors may result in congenital deformities?
- Infection.
- The use of live vaccines during pregnancy.
- Inappropriate medication (eg. Griseofulvin).
- Exposure to teratogenic chemicals during pregnancy.
Which cat breed is predisposed to spina bifida?
The Manx.
Which cat breed is predisposed to hypokalaemia?
The Burmese.
Which cat breed is predisposed to spasticity?
The Devon Rex.

Congenital & Hereditary Diseases

Arlo Guthrie — Tue, 21 Apr 2009 10:55:27 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:55:27

QUESTIONS

What is a congenital defect?
What is a hereditary defect?
Give 4 examples of congenital defects.
Give 4 examples of hereditary defects.
List 4 conditions which may be both congenital and hereditary.
Give an example of a breed of dog that is predisposed to entropion?
Give an example of a defect which may be both congenital and hereditary.
List 4 breeds of dog predisposed to hip dysplasia.
Name the organisations that run a screening programme to help reduce the risk of breeding from dogs affected with hip dysplasia.
How frequently should a breeding bitch be examined under the BVA eye scheme?
Give 2 examples of hereditary defects commonly seen in Border collies.
State the breed of dog predisposed to entropion, PRA and familial nephropathy.
In addition to genetic predisposition, what other factors may result in congenital deformities?
Which cat breed is predisposed to spina bifida?
Which cat breed is predisposed to hypokalaemia?
Which cat breed is predisposed to spasticity?

Obstetrics & Paediatrics

Arlo Guthrie — Tue, 21 Apr 2009 10:53:46 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:53:46

Introduction
Obstetrics is the branch of veterinary medicine and surgery covering pregnancy, parturition (labour) and the puerperium (the return of the body to normal after birth).

Paediatrics is the branch of medicine dealing with the care and development of the young and the treatment of diseases that affect them.

In practice we tend only to see problem births. The vast majority of queens and bitches kitten or whelp at home with relatively few problems.

This chapter covers all aspects of the pregnancy from breeding to the aftercare of the dam and litter. The veterinary nurse needs not only to be competent in emergency procedures such as assisting with a Caesarean, but must also be able to offer concise advice regarding all aspects of obstetrical and paediatric nursing. Many clients, particularly if they have not bred from an animal before, will telephone the surgery for advice beforehand.

Learning Objectives
The learning objectives of this chapter are:

To understand the difference between congenital and hereditary defects and be able to state examples.
To understand how heat in the queen and bitch differ, and be able to offer advice to clients with regard to seasons.
To comprehend the mating procedure in cats and dogs, and again be able to offer advice to clients regarding this subject.
To be able to competently undertake the care of the pregnant queen and bitch.
To understand how a foetus develops.
To competently be able to assist the veterinary surgeon with a Caesarean section including the monitoring of general anaesthesia and resuscitation of the neonates.
To be able to provide accomplished nursing care to orphaned neonates.
To be able to competently undertake the care of the lactating dam and her litter.
To understand the importance of neutering, and be able to advise clients as to the benefits of spaying and castration in animals that are not intended for breeding.

Anaesthesia & Analgesia - Glossary

Arlo Guthrie — Tue, 21 Apr 2009 10:51:39 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:51:39

Anaesthesia - loss of feeling or sensation in a part or the whole of the body; usually drug induced.

Analgesia - the relief of pain without causing unconsciousness.

Anticholinergic - a drug that inhibits the action of acetylcholine.

Apnoea - cessation of respiration.

Arrythmia - variation from the normal rhythm of the heart.

Ataractic - a tranquilliser.

Auscultation - examination of the internal organs by listening to their sound.

Basal narcosis - a state of unconsciousness produced prior to surgical anaesthesia.

Blood brain barrier - the membranous barrier that separates blood from the brain; it is permeable to water, oxygen, carbon dioxide, glucose, alcohol, general anaesthetics and some drugs.

Bradycardia - abnormally low heart rate.

Bradypnoea - abnormally low respiratory rate.

Cardiac tamponade - impairment of the heart function by haemorrhage or effusion into the pericardium.

Cyanosis - blue-grey mucous membranes; a sign of inadequate oxygenation of the blood.

Defibrillation - the restoration of normal heart rhythm in ventricular or atrial fibrillation.

Defibrillator - an instrument which restores normal heart rhythm by the application of a high voltage electric current.

Diuresis - increased excretion of urine.

Dyspnoea - laboured breathing.

Dysrhythmia - disturbance of a regularly occurring pattern.

Epidural - outside the dura mater. Epidural analgesia is a form of pain relief obtained by the injection of a local analgesic into the epidural space in order to block the spinal nerves.

Hypercapnia/hypercarbia - excess blood carbon dioxide.

Hyperpnoea - hyperventilation.

Hypertension - persistently high blood pressure.

Hypotension - persistently low blood pressure.

Hypoventilation - shallow breathing at a very slow rate which may cause a build up of carbon dioxide in the blood.

Hypoxia - inadequate oxygen in the tissues.

Laryngospasm - a reflex prolonged contraction of the laryngeal muscles; this may be associated with the clumsy passing of endotracheal tubes.

Narcotic - a drug that produces narcosis (unnatural sleep).

Neurolept - a drug which acts upon the nervous system.

Poikilothermic - describes an animal which is unable to control its body temperature such as neonates and reptiles.

Premedicant - drug/s given preoperatively in order to reduce fear and anxiety and to facilitate the induction, maintenance and recovery of anaesthesia.

Pulse deficit - a sign of atrial fibrillation; the pulse rate is slower than the apex beat.

Sedative - a sleep inducing drug; used to lessen excitement and reduce tension.

Soporific - sleep inducing.

Syncope - fainting.

Tachycardia - a higher than normal heart rate.

Tachypnoea - a higher than normal respiratory rate.

Thoracotomy - a surgical incision into the thorax.

Tracheostomy - a permanent or long term surgical opening into the trachea.

Tracheotomy - a temporary opening into the trachea.

Tranquilliser - a drug that allays fear and anxiety without inducing sleep.

Anaesthesia & Analgesia - Summary

Arlo Guthrie — Tue, 21 Apr 2009 10:50:59 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:50:59

My first anaesthetic experience some twelve years ago was a terrifying ordeal following a couple of weeks of "watch and learn". I was monitoring an eight year old St Bernard undergoing bilateral aural ablation; the veterinary surgeon was concentrating on the surgery and gave few directions and the only nurse was on holiday! The anaesthetic machine was an ancient Boyle's bottle affair, and we had no equipment such as pulse-oximeters or oesophageal stethoscopes. Subsequently I felt ill-prepared and nervous. Fortunately, no harm came to the poor dog in my care, however I was so aware that I would have been next to useless in an anaesthetic crisis that I was very nervous of anaesthesia for many months. Indeed, it was only once I joined an Approved Training Centre and received much needed and much improved training that I finally began to gain confidence.

Veterinary nursing has progressed in leaps and bounds since then and crash courses in anaesthesia are a thing of the past. The latest new improvements such as the advent of the Portfolio, the S/NVQ Qualifications and subsequent improved work place assessment methods go even further to maximise efficient and effective education in the science of anaesthesia.

There is no excuse for inadequate training, and particularly with such an important subject, a junior staff member should never be expected to undertake tasks which he or she feels may be beyond their capabilities. The veterinary surgeon is responsible for the patient during anaesthesia, and in addition a qualified veterinary nurse should also be on hand to supervise the trainee.

It is also down to the individual to speak out in cases of doubt. This could mean the difference between the life and death of a patient, and any problems must NEVER be ignored or brushed under the carpet to be dealt with later.

A list of points to recap:

Has the consent form for anaesthesia and surgical procedure been signed?
If the answer is NO it is ILLEGAL to go ahead with the procedure.
Are there any faults with the equipment?
If the answer is YES the procedure MUST BE DEFERRED until all equipment is 100% reliable.
Are you able to set up the equipment and use it correctly?
If the answer is NO you must ASK for assistance PRIOR to the procedure.
Has the patient shown any unusual or abnormal signs/symptoms since admission?
If the answer is YES, inform the veterinary surgeon AT ONCE noting the time and full details; remember to record the information on the patient's notes.
Has the owner informed you of any unsual or abnormal signs/symptoms that they may have noticed?
If the answer is YES, inform the veterinary surgeon PRIOR to admission of the patient since a further pre-operative assessment is likely to be necessary.
Are you competent and confident monitoring a patient's vital signs during anaesthesia?
If the answer is NO, a qualified veterinary nurse must be on hand to provide guidance and assistance.
Can you remain calm and provide the necessary assistance should an anaesthetic crisis occur?
If the answer is NO, you are likely to be a hindrance rather than a help during an emergency. ENSURE that a qualified veterinary nurse is on hand to perform emergency procedures; stand well back and refrain from asking questions until the crisis is resolved.
Are you aware of the potential risks to personnel involved in anaesthesia and do you always obey the local rules and follow the written systems of work?
If the answer is NO, then you represent a risk to yourself, patients and other personnel and should IMMEDIATELY SEEK TO RECTIFY THE SITUATION. If the answer is NO due to inadequate training then you must IMMEDIATELY INFORM THE PRACTICE PRINCIPAL who is duty bound to provide training in matters relating to health and safety.

Always refer to the above list and if there are any doubts or queries ALWAYS ask a superior. Any information that may be relevant to the case must be imparted to the veterinary surgeon and details recorded on the animal's In-patient and Anaesthesia forms.

Finally, it is important to be familiar with the amendment to the Veterinary Surgeons Act of 1991. Guidance of administration of anaesthesia is as follows and is taken from the RCVS Veterinary Nurses Committee: Chairman's Letter July 1998:

What a veterinary surgeon alone should be responsible for:
Induction and maintenance of anaesthesia and the management to full recovery of consciousness including the integrated steps below:

a) Clinical examination of the patient to assess the fitness of the animal to undergo anaesthesia.

b) Evaluation of clinical signs, further examination, and where necessary additional diagnostic tests.

c) Planning of the anaesthetic regime and selection of a suitable technique for that animal and the type of procedure to be performed.

d) Selection of the appropriate sedative, analgesia and other agents which may have to be administered as premedication.

Only a veterinary surgeon should be responsible for these initial procedures and the selection of the anaesthetic agents and the selection of route by which they will be administered. Furthermore, only a veterinary surgeon should administer and monitor the anaesthesia where the induction dose is either incremental or to effect; ie. intravenous or inhalation.

What a Veterinary Nurse may do:
Provided the veterinary surgeon is physically present during anaesthesia and immediately available for consultation, it would be in order for a veterinary nurse, whose name is on the List maintained by the RCVS to provide assistance by:

a) Administering the selected pre and post operative sedative, analgesic or other agents.

b) Administering prescribed non-incremental anaesthetic agents on the instruction of the directing veterinary surgeon.

c) Monitoring clinical signs and maintaining an anaesthetic record.

d) Maintaining anaesthetic by administering supplementary incremental doses of intravenous anaesthetic agents or adjusting the delivered concentration of anaesthetic agents, under the direct instruction of the supervising veterinary surgeon. The above guidelines apply to companion animals only.

Risk Assessment For Personnel - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:49:50 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:49:50

ANSWERS

Under what regulations does an employer have a duty to assess the risk of exposure to anaesthetic gases to his or her employees and take the appropriate measures to protect their health?
The COSHH (Control of Substances Hazardous to Health) Regulations 1988.
In addition to the COSHH Regulations, list other legislation relating to veterinary anaesthesia.
- The Health and Safety at Work Act 1974.
- The Control of Pollution Act 1974.
- RIDDOR (Reporting of Diseases and Dangerous Occurrence Regulations) 1980.
- Manual Handling Operations Regulations 1992.
What protective clothing must be available to staff working in the theatre?
- Gowns or theatre suits.
- Theatre headwear.
- Footwear such as clogs or wellington boots.
- Surgical gloves.
- Facemasks.
- Goggles.
- Disposable aprons.
List 10 ways in which theatre anaesthetic pollution may be minimised.
- Avoid administering anaesthetic gases via face masks.
- Use correctly fitting endotracheal tubes.
- Inflate the cuffs of endotracheal tubes.
- Employ an effective scavenge system (active scavengers are generally considered the most efficient).
- Do not turn on the nitrous oxide and volatile agent until the circuit is connected to the patient.
- Flush the patient circuit with oxygen for at least 30 seconds before disconnection.
- Flush the circuit with oxygen beforehand if the patient requires disconnection during anaesthesia.
- Fill vaporisers at the end of the operating session in a well ventilated area.
- Check all anaesthetic equipment daily and ensure that professional servicing of the anaesthetic machine is carried out every 6 months (keep a maintenance log book).
- Monitor anaesthetic gas pollution levels every 6 months.
What health problems are associated with prolonged exposure to anaesthetic gases?
- Neoplasia.
- Neuropathy.
- Bone marrow toxicity.
- Infertility.
- Miscarriage.
- Congenital abnormalities in the offspring of theatre personnel.
Name a potentially hazardous carrier gas.
Nitrous oxide; this is particularly harmful to expectant mothers since it crosses the placenta.
Why is the recovery area likely to prove more hazardous to personnel with regard to anaesthetic pollution than the theatre?
Animals exhale waste anaesthetic gases upon recovery and good ventilation is therefore vital in this area.
In addition to the health risks associated with anaesthetic gases (see Q5), what other hazards may be encountered relating to the subject of veterinary anaesthesia?
- Back injuries as a result of moving heavy patients or gas cylinders.
- Self-injection of harmful drugs.
- Zoonoses from handling patients.
- Fire/explosion risk from volatile gases.
- Bites and scratches during restraint for anaesthesia.
Describe how self-injection may be avoided.
- Ensure that animals are adequately restrained particularly during recovery.
- Avoid unnecessary handling of patients making an excitable recovery.
- Dispose of needles in sharps containers immediately after use.
- Never carry syringes and needles in pockets.
- Never walk around with a loaded syringe and needle unless it is securely sheathed.
List safety measures taken to avoid accidents involving gas cylinders.
- A hazard warning notice should be clearly displayed in the gas storage area.
- A "No Smoking" sign should be clearly displayed in the gas storage area.
- Cylinders should be handled carefully using a trolley if necessary.
- Cylinders should be stored in a cool, dry area in such a way that they will not fall or become damaged.
- Cylinders should not be exposed to high temperatures or sunlight.

Risk Assessment For Personnel

Arlo Guthrie — Tue, 21 Apr 2009 10:48:58 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:48:58

QUESTIONS

Under what regulations does an employer have a duty to assess the risk of exposure to anaesthetic gases to his or her employees and take the appropriate measures to protect their health?
In addition to the COSHH Regulations, list other legislation relating to veterinary anaesthesia.
What protective clothing must be available to staff working in the theatre?
List 10 ways in which theatre anaesthetic pollution may be minimised.
What health problems are associated with prolonged exposure to anaesthetic gases?
Name a potentially hazardous carrier gas.
Why is the recover area likely to prove more hazardous to personnel with regard to anaesthetic pollution than the theatre?
In addition to the health risks associated with anaesthetic gases (see Q5), what other hazards may be encountered relating to the subject of veterinary anaesthesia?
Describe how self-injection may be avoided.
List safety measures taken to avoid accidents involving gas cylinders.

Anaesthesia Of Exotics - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:47:47 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:47:47

ANSWERS

Why must particular care be taken with the anaesthesia of reptiles, amphibians, fish and invertebrates?
These species are poikilothermic (or cold blooded) which means that they are unable to regulate their own body temperature. They are therefore particularly susceptible to hypothermia.
Why are small mammals such as rats and gerbils at risk from hypothermia?
They have a large surface to volume ratio.
How might the risk of hypothermia be reduced during the anaesthesia of small mammals and exotics?
- Operating in a warm ambient environment free from draughts.
- Avoiding excess clipping of fur.
- Avoid over-enthusiastic preparation of the surgical site which may result in the animal becoming wet.
- Warm fluids prior to use.
- Use incubators and heat pads during the surgical procedure and recovery.
- Insulate the body of the animal with a proprietary material or bubble wrap if possible.
Which species must not be allowed to become too dry or hot, and should ideally be operated on wrapped in a damp cloth?
Amphibians such as frogs, toads, newts and salamanders.
Describe an induction tank suitable for amphibians and fish.
A container filled with a dilute solution of tricaine methane sulphonate or benzocaine. The container must be deep enough to immerse a fish, or to submerge an amphibian up to its nostrils. The container should not be too large (to discourage excess movement), heavy (to prevent it from being knocked over) and transparent (to enable close monitoring from all sides).
Describe an anaesthetic chamber.
An anaesthetic chamber, provided it is secure and not causing a pollution risk, may be of a proprietary type or home-made. It consists of a transparent container with an inlet for a tube to transport the gas from the machine and an outlet for a scavenge tube. If the volatile agent is placed within the chamber on absorbent material, this should be located so that the animal cannot come into direct contact with it.
Why should the anaesthetic chamber be made of glass or transparent plastic?
In order for the anaesthetist to observe the patient from all sides.
Why must care be taken if an anaesthetic chamber is made from materials other than glass?
The volatile agent may react with or cause certain plastics to melt. Harmful fumes may be given off.
For what purpose might a canvas or cloth bag be employed during the anaesthesia of exotic species?
- Restraint of small, wriggling animals and snakes for weighing.
- Recovery bag for birds.
What duration of pre-anaesthetic fasting is recommended for the following species: (i) Ferrets. (ii) Granivorous birds. (iii) Waterfoul and carnivorous birds. (iv) Chelonians & lizards. (v) Snakes.
- Ferrets - 12-16 hours.
- Granivorous birds - rarely required, but never more than 3 hours.
- Waterfowl & carnivorous birds - 4-10 hours.
- Chelonians & lizards - 18 hours.
- Snakes - 72-96 hours.
Why is it necessary to fast chelonians prior to anaesthesia?
In order to avoid compression of the lungs.
Why is it necessary to fast snakes prior to anaesthesia?
To prevent vomiting and the associated risk of aspiration pneumonia.
Name 2 species in which pre-anaesthetic fasting is unnecessary.
- Lagomorphs (rabbits and hares).
- Small rodents such as mice, hamsters and gerbils.
Why should small mammals and birds with a high metabolic rate not be fasted?
They may suffer hypoglycaemia.
Small mammals and exotics are particularly prone to stress. List ways in which induction may be made less traumatic.
- Acclimatisation of the animal to the handler/s and environment (although it is advised that physical contact is kept to a minimum).
- Using a competent member of staff to restrain the animal to avoid escapees.
- The use of premedicant drugs.
- Avoiding the use of bright lights.
- Working in a calm, quiet environment.
Why is it sensible to avoid placing birds and reptiles in dorsal recumbency whilst anaesthetised?
The weight of the viscera on the lungs may reduce tidal volume (the quantity of gas inspired and expired in one breath) and cause respiratory embarrassment.
If an anaesthetic circuit is to be used, what would be the most suitable and why?
The Ayres T piece, since it is suitable for animals weighing less than 10 kg (applicable for most exotics seen in practice) and has no valves meaning there is little resistance to breathing. The Jackson Rees modification means that IPPV may be performed if necessary.

Anaesthesia Of Exotics

Arlo Guthrie — Tue, 21 Apr 2009 10:46:46 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:46:46

QUESTIONS

Why must particular care be taken with the anaesthesia of reptiles, amphibians, fish and invertebrates?
Why are small mammals such as rats and gerbils at risk from hypothermia?
How might the risk of hypothermia be reduced during the anaesthesia of small mammals and exotics?
Which species must not be allowed to become too dry or hot, and should ideally be operated on wrapped in a damp cloth?
Describe an induction tank suitable for amphibians and fish.
Describe an anaesthetic chamber.
Why should the anaesthetic chamber be made of glass or transparent plastic?
Why must care be taken if an anaesthetic chamber is made from materials other than glass?
For what purpose might a canvas or cloth bag be employed during the anaesthesia of exotic species?
What duration of pre-anaesthetic fasting is recommended for the following species: (i) Ferrets. (ii) Granivorous birds. (iii) Waterfowl & carnivorous birds. (iv) Chelonians & lizards. (v) Snakes.
Why is it necessary to fast chelonians prior to anaesthesia?
Why is it necessary to fast snakes prior to anaesthesia?
Name 2 species in which pre-anaesthetic fasting is unnecessary.
Why should small mammals and birds with a high metabolic rate not be fasted?
Small mammals and exotics are particularly prone to stress. List ways in which induction may be made less traumatic.
Why is it sensible to avoid placing birds and reptiles in dorsal recumbency whilst anaesthetised?
If an anaesthetic circuit is to be used, what would be the most suitable and why?

Resuscitation Procedures For Cardiac Arrest - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 10:45:32 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:45:32

Resuscitation Procedures For Cardiac Arrest - Key Notes

CARDIAC ARREST

Inform the veterinary surgeon, and note the time.
Call for assistance.
Cease anaesthetic administration.
Establish a patent AIRWAY ideally with an endotracheal tube.
BREATHING - Ventilate the lungs with 100% oxygen - see key notes RESPIRATORY ARREST.
CIRCULATION - Position the patient in right lateral recumbency with the head tilting slightly downwards. Commence cardiac massage at a rate of 1 compression every half second in small animals and 1 compression every 2 seconds in larger dogs. Ideally 2 people should resuscitate the patient; one to perform respiration and the other to perform cardiac massage.
If alone, cardiac massage should be applied for 5 seconds, and then the chest inflated 3 times and repeated until the circulation restarts.
Open chest massage may be considered - if the chest is already open, closed massage does not produce a detectable pulse within 2 minutes or if ventricular fibrillation is diagnosed/suspected.
DRUGS - Drugs may be administered in accordance with the request of the veterinary surgeon eg. adrenaline (cardiac stimulant). And after circulation is re-established rapid intravenous fluids (to restore the normal volume of fluid to the circulation) and sodium bicarbonate (to correct acidosis) may be also administered.
Electrical defibrillation may be performed. Monitoring equipment must be disconnected and staff to stand well clear. For internal DC defibrillation, the electrodes are wrapped in saline soaked gauge and applied to the right atrium and left ventricle. The shock is applied for 0.1-0.5 seconds. The operator should be prepared for the animal to convulse, and must not touch the exposed electrodes, animal or operating table. External defibrillation involves the application of electrodes to the right thoracic wall in the region of the base of the heart and the left thoracic wall in the region of the apex.

Resuscitation Procedures For Cardiac Arrest - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 10:45:11 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:45:11

CARDIAC ARREST

Inform the veterinary surgeon, and note the time.
Call for assistance.
Cease anaesthetic administration.
Establish a patent AIRWAY ideally with an endotracheal tube.
BREATHING - Ventilate the lungs with 100% oxygen - see key notes RESPIRATORY ARREST.
CIRCULATION - Position the patient in right lateral recumbency with the head tilting slightly downwards. Commence cardiac massage at a rate of 1 compression every half second in small animals and 1 compression every 2 seconds in larger dogs. Ideally 2 people should resuscitate the patient; one to perform respiration and the other to perform cardiac massage.
If alone, cardiac massage should be applied for 5 seconds, and then the chest inflated 3 times and repeated until the circulation restarts.
Open chest massage may be considered - if the chest is already open, closed massage does not produce a detectable pulse within 2 minutes or if ventricular fibrillation is diagnosed/suspected.
DRUGS - Drugs may be administered in accordance with the request of the veterinary surgeon eg. adrenaline (cardiac stimulant). And after circulation is re-established rapid intravenous fluids (to restore the normal volume of fluid to the circulation) and sodium bicarbonate (to correct acidosis) may be also administered.
Electrical defibrillation may be performed. Monitoring equipment must be disconnected and staff to stand well clear. For internal DC defibrillation, the electrodes are wrapped in saline soaked gauge and applied to the right atrium and left ventricle. The shock is applied for 0.1-0.5 seconds. The operator should be prepared for the animal to convulse, and must not touch the exposed electrodes, animal or operating table. External defibrillation involves the application of electrodes to the right thoracic wall in the region of the base of the heart and the left thoracic wall in the region of the apex.

Resuscitation Procedures For Respiratory Arrest - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 10:44:22 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:44:22

RESPIRATORY ARREST

Inform the veterinary surgeon.
Call for assistance if required.
Cease anaesthetic administration.
Check for a heart beat.
Establish AIRWAY - intubation is the preferred method, extend the neck, pull the tongue forward, remove constrictive collars or dressings, check for obstructions.
Establish BREATHING - ventilate the lungs with 100% oxygen via a suitable circuit, administer 3-4 breaths rapidly followed by 6-12 breaths per minute thereafter. The lungs should be sufficiently inflated to produce visibly supra-normal chest wall excursions but must be allowed to deflate to a normal end-expiratory position.
Administer drugs and fluids according to the instructions of the veterinary surgeon. If apnoea is caused by an overdose of intravenous or intramuscular anaesthetic drug, fluids will hasten elimination by promoting diuresis. Antagonists to narcotic analgesics may be given if necessary. Immobilon, Hypnorm and Medetomidine may also be antagonised.

Resuscitation Procedures - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 10:43:19 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:43:19

When to take action - Inform the veterinary surgeon

Area Monitored	Normal	Abnormal
Respiratory pattern	Regular	Dyspnoea, irregular or ceased respiration
Respiratory rate	10-30bpm in cats and dogs	Bradypnoea or tachypnoea
Respiratory depth	Chest and reservoir bag movement observed	Breathing becomes shallow
Heart rate	60-180bpm in the dog 110-180bpm in the cat	The heart stops beating and the apex beat cannot be detected by auscultation
Pulse rate and depth	Regular	Pulse deficit, rhythm alters or becomes irregular
Mucous membranes	Pink in colour	Pale, cyanotic (blue) or ashen in colour
Capillary refill time	Less than 2 seconds	Greater than 2 seconds
Temperature	38.3-38.7 degrees C in the dog 38-38.5 degrees C in the cat	Pyrexia, hyperthermia or hypothermia

Also inform the veterinary surgeon in the event of equipment failure or any matter which gives rise to concern.

Anaesthetic Emergencies - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:41:35 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:41:35

ANSWERS

Treatment of an anaesthetic emergency must be prompt. List 3 important factors that will enable a crisis to be dealt with efficiently.
- The provision of a suitably stocked emergency kit.
- The provision of training in resuscitation procedures.
- The provision of a ready source of information with regard to emergencies.
List 6 properties of the emergency kit.
- Portable with easy access.
- Kept clean and tidy.
- Contains only essential items.
- Includes clear, concise instructions on resuscitation procedures.
- Dosage instructions clearly visible.
- Contains a list of contents to ensure that contents are replenished following use.
List drugs commonly found in the emergency kit.
- Sodium chloride 0.9% for intravenous infusion - for the correction of shock, dehydration and electrolyte imbalance.
- Potassium chloride - for hypokalaemia.
- Adrenaline injection - for cardiac arrest.
- Calcium borogluconate - for hypocalcaemia.
- Sodium bicarbonate - for electrolyte imbalance.
- Atropine sulphate - for bronchodilation and reduction of airway resistance, control of intra-operative vagally mediated bradycardia.
- Lignocaine hydrochloride - for cardiac arrythmias.
- Naloxone hydrochloride - antidote for morphine, pethidine, fluanisone-fentanyl (Hypnorm).
- Doxapram - respiratory stimulant.
- Isoprenaline - for vasodilation.
The examples listed above are by no means exhaustive. You may find many other drugs in practice with a role to play in emergency situations such as cardiac arrest or apnoea.
List instruments and equipment suitable for the emergency box. Every surgery will have variations upon this list and it is important to familiarise yourself with the contents in practice.
- Stop watch.
- Masks.
- Laryngoscope.
- Cuff inflator and tube clamps.
- Suction catheter and connector.
- Endotracheal tubes.
- Tracheotomy tubes.
- Selection of needles and syringes.
- Selection of intravenous catheters.
- Spirit.
- Curved scissors.
- Scalpel blades.
- 2.5cm Elastoplast or zinc oxide tape.
In the evident of an anaesthetic accident, what procedures are to be followed?
- Stay calm.
- Advise the veterinary surgeon.
- Call other staff for assistance.
- Assist with or carry out emergency treatment under the instructions of the veterinary surgeon (remembering the importance of "ABC" - airway, breathing, circulation.
- After the event the details must be recorded accurately on the patient's anaesthetic monitoring form and case notes.
Define the following terms: (i) Apnoea. (ii) Hypoxia. (iii) Hypercapnia.
- Apnoea - cessetion of breathing.
- Hypoxia - inadequate oygenation.
- Hypercapnia - excess blood carbon dioxide (also known as hypercarbia).
List five possible causes of apnoea.
- Intravenous anaesthetic drug overdose.
- Upper airway obstruction
- Acute event such as pneumothorax
- Chest wall fixation or immobility
- Failure of the brain to respond to carbon dioxide or oxygen
List are the signs of apnoea?
- Absence of breathing, although the patient may gasp.
- Staring eyes with dilated pupils.
- Spasmodic diaphragm contractions.
- Neck extended with twitching muscles.
- Blue or grey mucous membranes.
List possible reasons that may cause the brain to fail to respond to oxygen?
- Anaesthetic overdose.
- Hypothermia.
- Increased intracranial pressure as a result of inflammation or neoplasia.
- Severe head trauma.
What is the most common cause of hypoventilation?
Profound anaesthesia. The deeper the anaesthetic, the deeper the degree of respiratory depression.
What clinical signs may be indicative of an airway obstruction?
- Respiratory snoring.
- Paradoxical thoracic wall movement during inspiration (the abdomen moves outwards and the chest inwards).
List possible causes of an airway obstruction.
- Blood.
- Bronchospasm.
- Kinked, damaged or misplaced endotracheal tube.
- Gas.
- Pulmonary oedema.
- Soft tissue.
- Vomit.
Define laryngospasm.
A reflex prolonged contraction of the laryngeal muscles that is liable to occur on insertion or withdrawal of an endotracheal tube. Cats are more likely to be affected than dogs.
List 4 methods of preventing laryngospasm during endotracheal intubation.
- Select the correct sized endotracheal tube.
- Do not over inflate the cuff (and ensure that the cuff is deflated prior to removal of the endotracheal tube).
- Lubricate the endotracheal tube to aid passing.
- Use a topical local anaesthetic spray such as Intubeze (which my boss invented incidentally!).
List possible causes of bradypnoea during anaesthesia.
- Deep anaesthesia.
- Opioids.
- Hypothermia.
- Elevated intracranial pressure.
List possible causes of tachypnoea during anaesthesia.
- Inadequate anaesthesia.
- Pyrexia.
- Hypercapnia (hypercarbia).
- Restrictive lung lesions.
List possible causes of bradycardia during anaesthesia.
- Anaesthetic drug overdose.
- Terminal hypoxia.
- Vagal activity.
- Hyperkalaemia.
- Hypothermia.
List possible causes of tachycardia during anaesthesia.
- Inadequate anaesthesia.
- Hyperthermia.
- Hypercapnia (hypercarbia).
- Hypotension.
- Hypoxia.
- Antimuscarinic drugs.
- B agonists.
List possible causes of arrythmias during anaesthesia.
- Inadequate anaesthesia.
- Anaesthetic drug overdose.
- Electrolyte imbalance.
- Blood gas abnormalities.
- Medical conditions such as gastric dilation (associated with ventricular arrythmias).
- Some surgical conditions.
Why is hypotension a risk during anaesthesia?
Prolonged hypotension diminishes perfusion in the splanchnic and renal vasculature leading to tissue damage. In severe cases, myocardial and cerebral damage may result and prove fatal.
List possible causes of hypothermia during anaesthesia.
- Cold or draughty ambient environment.
- Excess clipping of hair.
- Over-enthusiastic preparation of the surgical site resulting in the patient and/or drapes becoming wet.
- Impaired hypothalamic thermoregulation as a result of anaesthetic drug administration.
- Vasodilation of the blood vessels of the skin.
- The cessation of skeletal muscle activity.
- Inhibited shivering.
- Exposed visceral surfaces.
- Cold, dry inspired gases.
What animals are most at risk from hypothermia during anaesthesia and why?
- Neonates - poikilothermic, underdeveloped and have a high ratio of surface area to volume.
- Young animals - underdeveloped and have a high ratio of surface area to volume.
- Birds - high ratio of surface area to volume.
- Small mammals such as hamsters, rats and chinchillas - high ratio of surface area to volume.
- Reptiles - poikilothermic.
- Geriatrics - impaired thermoregulatory reflexes.
How is the difference between core and periphery temperature measured?
By the simultaneous use of two calibrated thermistors placed at appropriate sites; such as over thebase of the heart via the oesophagus and on the lip.
What should be suspected if darkly coloured, slowly oozing blood is observed at the surgical site?
Poor perfusion.
What are the responsibilities of the veterinary nurse during the recovery period?
- Monitoring of the patient's vital signs (CRT, HR, PR & depth, RR & depth, temp, mm colour).
- Keep accurate records.
- Ensure that the patient is kept warm, clean and dry.
- Attend to any wounds and prevent interference.
- Administer drugs under the instruction of the veterinary surgeon.
- Monitor fluid and energy balance.
- Advise the veterinary surgeon of any problems immediately.
List reasons that may contribute to a prolonged recovery.
- Hypothermia - causes retarded expiration of volatile agents and the redistribution and metabolism of injectable drugs.
- Drugs such as ACP - especially in border collies, brachycephalic breeds and animals with impaired hepatic function.
- Other drug retention - as a result of inadequate perfusion and/or impaired hepatic/renal function.
- Very severe pain - this may result in depression (although excitation is more probable).
- Drug recycling - Immobilon is particularly prone to this.
What may cause excitation during the recovery period?
- Pain.
- Convulsions as a result of conditions such as epilepsy.
- Pharmacological phenomena (eg. after top-ups of thiopentone).
- Environmental factors (eg. light and noise).
List examples of accidents that may be associated with general anaesthesia. Briefly describe your actions in the event of such circumstances.
- Extravascular injection - promptly inject the site with sterile saline or water to dilute the drug and massage (thiopentone is particularly nasty as it causes skin sloughing).
- Drug overdose - Intubate, ventilate (with pure oxygen), cardiac compression if pulse weak or absent, administer drug agonists if available, administer intravenous fluids and inotropes if necessary.
- Hypostatic congestion - this is better prevented; turn the animal frequently (every 2 hours).
- Explosions and fires - raise the alarm, call emergency services, evacuate the premises and follow the fire drill.
- Bites and scratches by patients - seek treatment from the practice first aider and ensure that a report is noted in the accident book, visit the doctor or hospital if necessary.
- Self-administration of drugs - seek medical advice immediately.
List alternative methods of administering oxygen if an animal is not intubated.
- Via face mask.
- Transtracheal catheter.
- Intranasal catheter.
- Tracheostomy tube.

Anaesthetic Emergencies

Arlo Guthrie — Tue, 21 Apr 2009 10:40:49 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:40:49

QUESTIONS

Treatment of an anaesthetic emergency must be prompt. List 3 important factors that will enable a crisis to be dealt with efficiently.
List 6 properties of the emergency kit.
List drugs commonly found in the emergency kit.
List instruments and equipment suitable for the emergency box.
In the evident of an anaesthetic accident, what procedures are to be followed?
Define the following terms: (i) Apnoea. (ii) Hypoxia. (iii) Hypercapnia.
List 5 possible causes of apnoea.
What are the signs of apnoea?
List possible reasons that may cause the brain to fail to respond to oxygen?
What is the most common cause of hypoventilation?
What clinical signs may be indicative of an airway obstruction?
List possible causes of an airway obstruction.
Define laryngospasm.
List 4 methods of preventing laryngospasm during endotracheal intubation.
List possible causes of bradypnoea during anaesthesia.
List possible causes of tachypnoea during anaesthesia.
List possible causes of bradycardia during anaesthesia.
List possible causes of tachycardia during anaesthesia.
List possible causes of arrythmias during anaesthesia.
Why is hypotension a risk during anaesthesia?
List possible causes of hypothermia during anaesthesia.
What animals are most at risk from hypothermia during anaesthesia and why?
How is the difference between core and periphery temperature measured?
What should be suspected if darkly coloured, slowly oozing blood is observed at the surgical site?
What are the responsibilities of the veterinary nurse during the recovery period?
List reasons that may contribute to a prolonged recovery.
What may cause excitation during the recovery period?
List examples of accidents that may be associated with general anaesthesia. Briefly describe your actions in the event of such circumstances.
List alternative methods of administering oxygen if an animal is not intubated.

Monitoring Periods & Planes Of Anaesthesia - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:39:44 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:39:44

ANSWERS

How frequently should an anaesthetised animal be checked?
At least every 5 minutes (the results should be recorded on an anaesthetic chart).
What instrument is used to find out the tidal volume of a patient?
Wright's resprometer.
List instruments useful in the monitoring of the anaesthetised animal.
- Stethoscope (ideally an oesophageal stethoscope).
- Thermometer.
- Pulse-oximeter.
- ECG machine.
- Blood pressure monitor.
- Respiratory monitor.
- CVP (central venous pressure) manometer.
- Blood-gas analysis equipment (to monitor C02 levels).
Under general anaesthesia, the respiratory rate should be similar to the resting rate in a conscious animal. What might cause a reduced respiratory rate under anaesthesia?
- Increasing depth of anaesthesia.
- Induction by barbiturates.
Why is it essential to ensure that cardiac output is maintained during anaesthesia?
In order to provide adequate perfusion of tissues and vital organs including the brain, heart and kidneys.
When monitoring pulse rate and depth, why is it advisable to palpate a peripheral pulse (such as the labial or sublingual) rather than a central pulse (such as the femoral)?
Peripheral pulses are more sensitive to changes in the circulation and thus abnormalities will be detected more promptly.
Blood pressure measurement provides a clear indication of the peripheral circulation. Describe 2 methods of monitoring blood pressure.
- Directly - by arterial cannulation connected to a pressure transducer.
- Indirectly - using an occlusive cuff and Doppler detector or machine.
What might pale mucous membranes be indicative of?
- Hypotension.
- Hypovolaemia.
What might cyanotic (blue) mucous membranes be indicative of?
Hypoxia (inadequate oxygenation).
List 4 conditions that may be indicated by an increased capillary refill time.
- Hypotension.
- Hypovolaemia.
- Toxaemia.
- Haemorrhage.
Why is the measurement of urine output useful in the monitoring of an anaesthetised patient?
A urine output in excess of 1ml/kg/hr represents adequate renal perfusion and therefore is an indicator of vital organ performance. Catheterisation of the urinary bladder is performed and collected urine weighed (1ml of urine = 1g).
How are reflexes used to assess the depth of anaesthesia?
As the level of anaesthesia deepens, muscle tone is lost.
List reflexes commonly used to assist in the assessment of the level of unconsciousness.
- Jaw tone.
- Pedal withdrawal reflex.
- Palpebral reflex (blinking).
A patient is under anaesthesia; the pupils are dilated and the eyes are in a normal position. What is this indicative of?
Very deep anaesthesia.
Describe the position of the eye under moderately deep anaesthesia.
The eye rotates downwards and medially.
Why do patients become hypothermic during anaesthesia?
Anaesthesia depresses the hypothalamus which in turn depresses temperature regulation.
List the 5 categories of the anaesthetic period.
- Pre-operative/preparation period.
- Pre-anaesthetic/pre-medication period.
- Induction.
- Maintenance.
- Recovery.
List methods in which the correct body temperature may be maintained during anaesthesia.
- Warm ambient environment.
- Environment free from draughts.
- The use of heat pads.
- Careful surgical preparation of the patient including the avoidance of creating overlarge clipped areas and the use of cold wet drapes.
- Provision of blankets during recovery.
List actions taken during the pre-operative/preparation period.
- Thorough clinical examination of the conscious patient.
- Administration of drugs to control pre-existing conditions if necessary.
- Checking of equipment prior to use.
The pre-anaesthetic/pre-medication period involves the administration of premedicant drugs. List common reasons for the use of pre-meds (see Module 3).
- Sedation - in order to relax the patient (particularly during induction) which may prove traumatic).
- Analgesia - to provide pain relief.
- Anaesthetic sparing effect.
- Reduction of undesirable side effects of anaesthesia such as salivation and vomiting.
List the 4 stages of anaesthesia.
- Voluntary excitement.
- Involuntary excitement.
- Surgical anaesthesia (of which there are 3 planes).
- Overdosage.
Briefly describe the stage of voluntary excitement.
- INDUCTION UNTIL UNCONSCIOUSNESS PRESENT.
- Apprehension and resistance - generalised sympatho-adrenal response to threat.
- Disorientation.
- Pulse and respiratory rate increased.
- Pupil dilated.
- Skeletal muscle activity.
- Hyper-reflexia.
- Possible breath holding, vocalisation, salivation, urination, defecation.
Briefly describe the stage of involuntary excitement.
- ONSET OF UNCONSCIOUSNESS TO RHYTHMIC BREATHING.
- Cranial nerve reflexes present - possibly hyperactive.
- Eyes initially wide open and pupils dilated, later rotate to ventromedial position.
- Brisk response to pedal reflex.
- Irregular breathing and gasping becomes regular.
Describe the planes of surgical anaesthesia.
- Regular, deep respiration with minute volume proportional to surgical stimulation. Light anaesthesia of a depth only suitable for superficial surgery.
- Muscle relaxation more apparent. Suitable depth for most surgery.
- Intercostal lag between inspiration and expiration. Deep anaesthesia suitable for all procedures.
Describe signs of anaesthetic overdose.
- Progressive respiratory failure eventually resulting in the cessation of diaphragmatic function.
- Very rapid or very slow pulse rate which becomes impalpable.
- Eyes open in central position with maximally dilated pupils and dry corneas.
- Mucous membranes cyanotic, finally turning grey.
- Prolonged CRT.
- Accessory respiratory activity representing agonal gasping ( indicated by throat twitching).
Why should excess levels of anaesthesia be avoided?
- Recovery is prolonged.
- Causes unnecessary cardio-pulmonary depression.
- Limits organ perfusion which may result in post-operative organ failure.
- May cause cardiac arrest.
Why is it essential to maintain an adequate depth of anaesthesia?
- To prevent the animal from waking up during a surgical procedure.
- Movement of the patient may compromise surgery.
- The animal may extubate itself or bite through the endotracheal tube.
- Arrythmias and cardiac arrest may result from catecholamine release.
- The uptake of anaesthesia may be impaired by tachypnoea.

Monitoring Periods & Planes Of Anaesthesia

Arlo Guthrie — Tue, 21 Apr 2009 10:38:57 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:38:57

QUESTIONS

How frequently should an anaesthetised animal be checked?
What instrument is used to find out the tidal volume of a patient?
List instruments useful in the monitoring of the anaesthetised animal.
Under general anaesthesia, the respiratory rate should be similar to the resting rate in a conscious animal. What might cause a reduced respiratory rate under anaesthesia?
Why is it essential to ensure that cardiac output is maintained during anaesthesia?
When monitoring pulse rate and depth, why is it advisable to palpate a peripheral pulse (such as the labial or sublingual) rather than a central pulse (such as the femoral)?
Blood pressure measurement provides a clear indication of the peripheral circulation. Describe 2 methods of monitoring blood pressure.
What might pale mucous membranes be indicative of?
What might cyanotic (blue) mucous membranes be indicative of?
List 4 conditions that may be indicated by an increased capillary refill time.
Why is the measurement of urine output useful in the monitoring of an anaesthetised patient?
How are reflexes used to assess the depth of anaesthesia?
List reflexes commonly used to assist in the assessment of the level of unconsciousness.
A patient is under anaesthesia; the pupils are dilated and the eyes are in a normal position. What is this indicative of?
Describe the position of the eye under moderately deep anaesthesia.
Why do patients become hypothermic during anaesthesia?
List the 5 categories of the anaesthetic period.
List methods in which the correct body temperature may be maintained during anaesthesia.
List actions taken during the pre-operative/preparation period.
The pre-anaesthetic/pre-medication period involves the administration of premedicant drugs. List common reasons for the use of pre-meds (see Module 3).
List the 4 stages of anaesthesia.
Briefly describe the stage of voluntary excitement.
Briefly describe the stage of involuntary excitement.
Describe the planes of surgical anaesthesia.
Describe signs of anaesthetic overdose.
Why should excess levels of anaesthesia be avoided?
Why is it essential to maintain an adequate depth of anaesthesia?

Safety With Gaseous Anaesthesia - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 10:37:29 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:37:29

There are many potential hazards that may arise from anaesthesia; these include:

Anaesthetic gas pollution (scavenge systems are essential).
Self-injection with harmful drugs (proper restraint of patients during induction helps to prevent accidents).
Explosions and fire (some electrical items should not be used in the presence of volatile anaesthetics).

In addition to the dangers to personnel, every animal undergoing an anaesthetic is at a certain degree of risk. Patients with pre-existing disease affecting the respiratory or cardiovascular system and those suffering from shock are classed as high risk cases and no matter how carefully they are monitored throughout the procedure that risk will always be present. However, dangers associated with equipment and apparatus can be virtually eliminated by frequent thorough safety checks, careful use and regular maintenance and servicing.

In the practical examination you may be asked to set up an anaesthetic circuit; remember that in practice you would never simply attach a piece of equipment to the anaesthetic machine without having at least first checked the gas supply and that of the vaporiser. It doesn't take a minute just to twist the vaporiser control and check that it dials correctly (remember to set it back to zero), nor is it time-consuming to press the emergency oxygen flush. It is sensible to keep a list of all the necessary checks and soon they will become second nature.

THE ANAESTHETIC MACHINE

1) Scavenge system - Before even thinking about touching the machine, check that the scavenge system is in place. A scavenge system is required by law to protect all involved in anaesthesia and should ALWAYS be used. Check any piping and casing for cracks or damage. If a fluabsorber (activated charcoal) is used it must be weighed regularly to ensure that it is replaced when spent. Other systems are passive, active-passive and active. The latter is the most efficient of all types.

2) Gas supply and flowmeter - Ensure that all cylinders are closed and fitted securely to the hanger yolk. The flowmeter control valves must also be closed since a rush of gas could cause the floates to hurtle upwards and cause damage. Press the oxygen flush to remove any residual gases from the machine and check that the pressure gauges read zero. Rotate the spindle of the oxygen cylinder slowly in an anti-clockwise direction and note the reading of the pressure gauge. Open the flowmeter control and ensure that the bobbin is freely floating; dirt or non-vertical positioning can cause inaccuracies and indicate the need for urgent servicing of the machine. Close the flowmeter and press the oxygen flush. Replace the cylinder if necessary and label as "in use" or "full" accordingly. If the machine holds a spare cylinder, this should also be tested. The nitrous oxide cylinders are checked in the same way but remember that the oxygen MUST be on or the alarm will sound. A scavenge pipe connected directly to the free gas outlet will prevent pollution.

3) Vaporiser - Ensure that the vaporiser is full before use. Calibrated vaporisers are agent specific and the port should be filled with a key-ended tube to prevent spillage and the use of the wrong anaesthetic. Rotate the dial to ensure that it moves correctly and then set to zero. Check that the filling port is tightly closed.

4) Oxygen flush - The oxygen flush (or emergency oxygen) is usually activated by a button located prominently on the front of the anaesthetic machine. Oxygen arrives directly from the cylinder and bypasses the vaporiser. Press the button and check for the high flow of oxygen from the common gas outlet.

5) Over pressure valve - The over pressure valve is useful for testing the system for leaks. Press the oxygen flush and occlude the common gas outlet. An alarm should sound when the valve is opens. If the alarm does not sound, gas is likely to be escaping elsewhere.

6) Nitrous oxide cutout device - Ensure the curtailment of nitrous oxide flow by opening both the oxygen and nitrous oxide flow valves and then closing that of the oxygen. Both floates should fall simultaneously and an alarm should sound.

7) Emergency air intake valve - The emergency air intake valve is opened by the inspiratory effort of the patient should gas flow from the machine stop. Room air then enters the system. Test the valve by attaching a length of pipe to the common gas outlet and then apply suction. The valve will open once a sufficient vacuum is present and an alarm will sound.

CIRCUITS

Check tubing for cracks, holes and dirt. Circuits should be hung when not in use and not kinked or squashed. Coaxial systems (where one pipe resides within another) may be difficult to assess.
Check reservoir bags for leaks; rubber is particularly perishable, especially if cleaned or stored incorrectly. Other rubber articles such as masks and endotracheal tubes should also be examined. Inflate the cuffs of endotracheal tubes prior to use.
Ensure that all connectors are removed prior to cleaning and correctly replaced. Again, check for cracks and other damage.
Check that any valves open and close freely.
If Waters canisters are used, the soda lime must be replaced once spent.

The importance of good maintenance of anaesthetic equipment cannot be stressed enough. Professional servicing should be carried out every 6 months and it is advisable to keep a file containing guarantees, instructions and service records for reference. All items should be cleaned and stored according to the manufacturer's instructions. If you are unsure of any aspect regarding the equipment be it how to use it, clean it, store it or whether it is damaged - ALWAYS ASK; you may prevent an accident.

Preparation Of Equipment - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 10:35:49 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:35:49

Preparation Of Equipment - Practical Task

This task is best considered in 3 steps:

Induction.
Maintenance.
Ancillary equipment.

Whilst most of the instruments and apparatus need not be sterile; they must be clean and well maintained. Remember however, that sterility is essential for intravenous catheterisation and therefore the site for venipuncture (usually the cephalic vein) is to be prepared as for surgery. Intravenous catheters MUST be sterile to reduce the risks of infection and thrombophlebitis (inflammation of a vein). Clean the preparation surface with disinfectant (such as a peroxide - Virkon or a halogenated tertiary amine hydrochloride - Trigene), dry the surface and lay down a clean paper or cotton drape upon which the smaller items of equipment are to be placed. The necessary equipment is listed below along with the uses for each:

Clippers or clean curved scissors - to clip the hair from the venipuncture site (usually the cephalic vein). A pair of scissors should also be available to cut lengths of tape and bandage (this blunts them so do not use the same pair as those used for clipping hair!).
Antiseptic solution - to clean the site prior to venipuncture. This should be contained within a suitable receptacle such as a medium-sized kidney dish. Chlorhexidine (Hibiscrub) or povidone iodine (Pevidine) are suitable.
Lint free swabs or cotton wool - to apply the antiseptic solution. Cotton wool may leave fibres, so swabs are preferable.
70% Alcohol solution such as Industrial Methylated Spirit - applied to the skin following the antiseptic solution to provide residual bactericidal activity. Contamination is best avoided by direct application from a plastic bottle.
Note: Care not to soak tiny patients due to heat loss on evaporation of alcohol solution.
Sterile catheter - inserted into the vein to allow administration of the induction agent. It should be of a suitable gauge for the patient. An over-the-needle catheter or butterfly scalp vein set are ideal, but a normal injection needle can be utilised. A scalpel blade (size 10 or 15) is necessary to expose the vein if a scalp set is used.

Catheter Size

Patient Suitability

24-22 guage

Cats and small dogs

22-20 guage

Medium dogs

20-18 guage

Large dogs
Sterile syringe loaded with the induction agent - the amount prepared should be of a suitable quantity for the patient. Accurate dose rates are essential. Agents such as Thio-pentone must be reconstituted before use at the correct percentage solution. Remember that a 5% solution contains 5g of anaesthetic agent in 100mls, while a 2.5% solution contains 2.5g of anaesthetic agent in 100mls. Further information may be found in Book 1 - Pharmacy and Dispensing. When using glass vials, dispose of the snap-tops carefully in the sharps container, and always seal up the vial and refrigerate if necessary after use.
Adhesive tape strips - to hold the syringe in place or tape in the catheter. Micropore is ideal due to its transparency which allows visualisation of the syringe gauge beneath it. Also, it is not as adhesive as Elastoplast which tends to pull out the patient's hair when removed unless spirit is used to dissolve the glue. Zinc tape or Elastoplast however is preferable for securing a catheter since it is stronger.
Rubber stopper or three way tap - to seal the catheter. It is beneficial for the catheter to remain in place throughout the anaesthetic since a patent intravenous route is readily available for the administration of emergency drugs and or fluids. Rubber stoppers are preferable to plastic since drugs can be administered directly without their removal. Heparin should be available in case of a blockage at 4 units per ml dilution in saline (1:1000 Heparin).
Sterile water - for injection into the venipuncture site in the event of extravasation (accidental injection outside of the vein). Drugs such as Thio-pentone are extremely irritant and can cause severe skin sloughing if extravasation occurs, and therefore must be diluted immediately.
Endotracheal tube and connector - these connect the patient to the anaesthetic circuit. The endotracheal tube is passed through the larynx and glottis to the trachea and maintains a patent airway. The connector attaches the proximal end of the tube to the circuit. Dirty or cracked tubes must never be used. A wide range of sizes are available but as a general guide; a tube of 3-4mm in diameter is usually suitable for cats, while a tube of 8-9mm in diameter should be appropriate for a 20kg dog.
Cuff inflator - to enable inflation of the cuff at the distal end of the endotracheal tube. Cuffed tubes are considered superior since they provide an airtight seal within the trachea. Inflation prior to use ensures that tubes with damaged cuffs are not used. Care on inflation of cuff needs to be taken as over inflation can result in tracheal damage.
Bandage strips - to secure the proximal end of the endotracheal tube in place. Open weave bandage of 2.5cm width is suitable. A length is tied around the tube, then secured caudally between the ears or over the muzzle depending upon head shape.
Water-soluble lubricant gel - enables ease of placement of the endotracheal tube and may contain local anaesthetic which also facilitates the procedure. Xylocaine gel and Lignocaine spray may be used.
Oesophageal stethoscope - used to monitor the patient's heart during anaesthesia.
Rectal thermometer and lubricant - used to monitor the patient's temperature during anaesthesia. Remember that general anaesthesia causes a decrease in body temperature and that is therefore vital to keep the patient dry and warm.
Other items -
1. Heat pad.
2. Emergency kit.
3. Pulseoximeter.
4. ECG machine.
These items are generally too large to lay out for use in the practical examination, but are very important and therefore should never be overlooked in practice.

Finally, small animal anaesthesia should never be performed without access to an anaesthetic machine and suitable circuit. Even if a patient is only to undergo minor surgery where gaseous maintenance is not considered necessary, a patent airway and immediate access to oxygen could prevent a fatality should a problem arise.

Anaesthetic machine - for the maintenance of anaesthesia with volatile agents. Ensure that sufficient gas is available and that the vaporiser is full. A spanner and spare washers should be to hand and an efficient scavenge system is essential.

Anaesthetic circuit - for the delivery of volatile gases from the machine to the patient and the removal of carbon dioxide. The circuit should be of a suitable size and type for the patient. If a reservoir bag is used, this must be checked prior to use for leaks. Soda lime canisters must be checked and replenished if necessary.

Preparation Of Equipment - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 10:35:09 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:35:09

This task is best considered in 3 steps:

Induction.
Maintenance.
Ancillary equipment.

Clippers or clean curved scissors - to clip the hair from the venipuncture site (usually the cephalic vein). A pair of scissors should also be available to cut lengths of tape and bandage (this blunts them so do not use the same pair as those used for clipping hair!).
Antiseptic solution - to clean the site prior to venipuncture. This should be contained within a suitable receptacle such as a medium-sized kidney dish. Chlorhexidine (Hibiscrub) or povidone iodine (Pevidine) are suitable.
Lint free swabs or cotton wool - to apply the antiseptic solution. Cotton wool may leave fibres, so swabs are preferable.
70% Alcohol solution such as Industrial Methylated Spirit - applied to the skin following the antiseptic solution to provide residual bactericidal activity. Contamination is best avoided by direct application from a plastic bottle.
Note: Care not to soak tiny patients due to heat loss on evaporation of alcohol solution.
Sterile catheter - inserted into the vein to allow administration of the induction agent. It should be of a suitable gauge for the patient. An over-the-needle catheter or butterfly scalp vein set are ideal, but a normal injection needle can be utilised. A scalpel blade (size 10 or 15) is necessary to expose the vein if a scalp set is used.

Catheter Size

Patient Suitability

24-22 guage

Cats and small dogs

22-20 guage

Medium dogs

20-18 guage

Large dogs
Sterile syringe loaded with the induction agent - the amount prepared should be of a suitable quantity for the patient. Accurate dose rates are essential. Agents such as Thio-pentone must be reconstituted before use at the correct percentage solution. Remember that a 5% solution contains 5g of anaesthetic agent in 100mls, while a 2.5% solution contains 2.5g of anaesthetic agent in 100mls. Further information may be found in Book 1 - Pharmacy and Dispensing. When using glass vials, dispose of the snap-tops carefully in the sharps container, and always seal up the vial and refrigerate if necessary after use.
Adhesive tape strips - to hold the syringe in place or tape in the catheter. Micropore is ideal due to its transparency which allows visualisation of the syringe gauge beneath it. Also, it is not as adhesive as Elastoplast which tends to pull out the patient's hair when removed unless spirit is used to dissolve the glue. Zinc tape or Elastoplast however is preferable for securing a catheter since it is stronger.
Rubber stopper or three way tap - to seal the catheter. It is beneficial for the catheter to remain in place throughout the anaesthetic since a patent intravenous route is readily available for the administration of emergency drugs and or fluids. Rubber stoppers are preferable to plastic since drugs can be administered directly without their removal. Heparin should be available in case of a blockage at 4 units per ml dilution in saline (1:1000 Heparin).
Sterile water - for injection into the venipuncture site in the event of extravasation (accidental injection outside of the vein). Drugs such as Thio-pentone are extremely irritant and can cause severe skin sloughing if extravasation occurs, and therefore must be diluted immediately.
Endotracheal tube and connector - these connect the patient to the anaesthetic circuit. The endotracheal tube is passed through the larynx and glottis to the trachea and maintains a patent airway. The connector attaches the proximal end of the tube to the circuit. Dirty or cracked tubes must never be used. A wide range of sizes are available but as a general guide; a tube of 3-4mm in diameter is usually suitable for cats, while a tube of 8-9mm in diameter should be appropriate for a 20kg dog.
Cuff inflator - to enable inflation of the cuff at the distal end of the endotracheal tube. Cuffed tubes are considered superior since they provide an airtight seal within the trachea. Inflation prior to use ensures that tubes with damaged cuffs are not used. Care on inflation of cuff needs to be taken as over inflation can result in tracheal damage.
Bandage strips - to secure the proximal end of the endotracheal tube in place. Open weave bandage of 2.5cm width is suitable. A length is tied around the tube, then secured caudally between the ears or over the muzzle depending upon head shape.
Water-soluble lubricant gel - enables ease of placement of the endotracheal tube and may contain local anaesthetic which also facilitates the procedure. Xylocaine gel and Lignocaine spray may be used.
Oesophageal stethoscope - used to monitor the patient's heart during anaesthesia.
Rectal thermometer and lubricant - used to monitor the patient's temperature during anaesthesia. Remember that general anaesthesia causes a decrease in body temperature and that is therefore vital to keep the patient dry and warm.
Other items -
1. Heat pad.
2. Emergency kit.
3. Pulseoximeter.
4. ECG machine.
These items are generally too large to lay out for use in the practical examination, but are very important and therefore should never be overlooked in practice.

Finally, small animal anaesthesia should never be performed without access to an anaesthetic machine and suitable circuit. Even if a patient is only to undergo minor surgery where gaseous maintenance is not considered necessary, a patent airway and immediate access to oxygen could prevent a fatality should a problem arise.

Safe Use Of Anaesthetic Equipment - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:30:49 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:30:49

ANSWERS

How should volatile agents be stored?
Volatile agents (eg. Fluothane and Halothane) should be stored in their original packaging at room temperature. The amber bottles in which they are supplied, plus the protective cardboard outer helps to prevent degeneration by light. Volatile agents should never be left on a windowsill as heat will cause evaporation and may represent an explosion hazard. The lid must be tightly applied in order to prevent spillage and evaporation, both of which pose a risk to staff who should not inhale the vapours.
How should gas cylinders be stored?
Gas cylinders should be stored outside of the surgery, ideally in a shed or storage box designated solely for this purpose. The area should be cool, clean and dry to prevent any damage to the cylinders. Full cylinders should be marked clearly as such; most have a red seal which is removed once the cylinder is in use. Hazard warning signs stating that gases are stored and the prohibition of smoking must be clearly displayed.
How should anaesthetic circuits be cleaned and stored?
- Turn off the anaesthetic gases and close the cylinders.
- Remove the anaesthetic circuit from the machine detaching it from the common gas outlet.
- Disassemble the circuit and gently clean tubes, connectors and rebreathing bags in mild detergent to remove organic matter such as blood and saliva.
- Rinse well.
- A disinfectant solution may then be used to kill bacteria, but thorough rinsing must be performed following this procedure.
- Hang tubes and bags to dry in a warm environment, remembering that rubber rebreathing bags are perishable and should not be exposed to extremes in temperature.
- Carefully check each component of the circuit for damage before reassembling when dry.
- Circuits should be stored in a clean, dry and dust free environment.
What is the procedure for the cleaning of endotracheal tubes?
First use a detergent solution to remove organic matter such as blood and saliva. Special brushes are available which may be passed through the entire tube to ensure that the inside is thoroughly cleaned and that there are no blockages. Rinse well before hanging to dry. Remember that endotracheal tubes have a limited life and that the rubber balloons are particularly prone to damage. Always inflate the balloon before storage to ensure that there are no punctures or blockages.
NB. Some practices use a cold sterilising solution such as Novasapa following cleaning with a detergent. Again, this should be rinsed off thoroughly.
Explain the importance of good ventilation and an efficient scavenge system when inhalation agents are employed.
Exposure to anaesthetic gases is a serious risk to personnel and is associated with neoplasia, neuropathy, infertility and bone marrow toxicity. In pregnant women a high incidence of abortion and congenital abnormalities have been reported. It is therefore an absolute necessity that a suitable scavenge system is employed (active types are considered the most efficient). Good ventilation is also essential, particularly in the recovery area where the patients exhale waste gases.
6) What items should be close to hand on the anaesthetic trolley and why?
- Lubricant - to aid the passing of the endotracheal tube; clumsy intubation may result in laryngospasm.
- 2.5cm White open weave bandage - to securely tie in the endotracheal tube.
- Cuff inflator - to inflate the balloon of the endotracheal tube and prevent the patient from breathing around it.
- Oesophageal stethoscope - for monitoring the patient's heart during anaesthesia.
- Rectal thermometer - to monitor the temperature of the patient during anaesthesia.
- Monitoring sheet - to record details of the anaesthetic and the depth of the patient throughout the procedure.
- Full/in-use/empty cylinder labels - to ensure that the correct gas cylinder is always in use.
- Spanner - to tighten cylinders to the hanger yolk and prevent leakage.
- Cylinder washers - to create a seal between the cylinder and hanger yolk, again preventing leakage.
- Curved scissors, antiseptic solution, swabs, spirit, scalpel blade and intravenous catheters - to gain venous access for the administration of fluids and/or drugs in an anaesthetic emergency.
- Emergency drugs - see Module 8.
List 6 important checks to be made to the anaesthetic machine prior to use.
- Ensure that the scavenge system is attached.
- Check the gas supply and flow meters.
- Ensure that the vaporiser is full.
- Check the emergency oxygen (oxygen flush) and emergency air intake valve.
- Check the over pressure valve.
- Check the nitrous oxide cut out device.
Practical Task 2 - Safety Aspects of the Anaesthetic Machine and Circuits covers this subject in detail.
In addition to your answers to Q7, list 6 actions that should be carried out on a daily basis to maintain equipment used in gaseous anaesthesia.
- Replenish any items used from the emergency box.
- Check circuits, rebreathing bags, endotracheal tubes and connectors for damage and replace if necessary.
- Remove and replenish empty gas cylinders.
- Check the status of soda-lime if used and replace if necessary.
- Thoroughly clean circuits (see Q3).
- Thoroughly clean the anaesthetic machine and trolley (see Q9).
How should the anaesthetic machine be cleaned?
- Before the day's procedures all surfaces of the anaesthetic machine should be damp dusted in order to maintain sterility in the theatre.
- Between use, any organic material such as blood or saliva should be removed with a damp cloth and detergent (care must be taken not to use too much water as this may cause damage to the machine); ensure that patients do not ingest soap bubbles!
- At the end of the day, the gas cylinders should be turned off, circuits disconnected and everything removed from the anaesthetic trolley; clean all surfaces including the vaporiser and cylinders with detergent to remove organic matter and then use a suitable disinfectant such as Trigene diluted to the correct strength.
  NB. If used, Schraeder probes should be removed from the wall socket and the pipes neatly coiled.
How frequently should professional servicing of the anaesthetic machine be performed?
Every six months. A service logbook should be kept and the anaesthetic machine itself must be labelled with a sticker showing the date of the last service and when the next one is due.
Describe a pulse oximeter.
The pulse oximeter is a photoelectric instrument that measures the oxygen saturation of a patient's blood and shows a digital display of the pulse rate. The machine should never be relied upon as a sole source of reassurance however. The patient is connected to the machine by a probe which usually attaches to the tongue, lip or ear, and by measuring the absorption of selected wavelengths of light arterial oxygen saturation is interpreted. Always refer to the manufacturers' instructions as to operation and maintenance and ensure that batteries are not allowed to run low.
Describe a laryngoscope.
A laryngoscope consists of a handle, blade and light source. It is used to depress the base of the tongue and evert the epiglottis during intubation.
Describe the 4 types of scavenge system in use in veterinary practice; which is the most efficient? The types are listed below in order of efficiency (with the most efficient first):
- Active - consisting of a transfer, receiving and disposal system involving an active suction unit such as a fan or pump.
- Active-passive - the use of a wide bore tube from the expiratory valve of the circuit which passes the gas to a forced ventilation system.
- Passive (to outside) - reliant upon the patient's respiratory efforts to transfer the gases via a wide bore tube to the outside.
- Passive (to charcoal absorber) - as above but the gases are chemically absorbed rather than transferred to the outside (nitrous oxide is not absorbed by this method).
How would you gauge the content of gas cylinders, soda lime canisters, charcoal absorbers and volatile agent levels?
- Gas cylinders - may be weighed, monitor the pressure/contents gauge once the cylinder is attached to the anaesthetic machine.
- Soda lime canisters - observe for colour change (be careful, because some soda lime changes from pink to white when spent, some changes from white to mauve).
- Charcoal absorbers - must be regularly weighed.
- Volatile agent - Monitor the measuring gauge on the vaporiser of the anaesthetic machine.
Describe the function of the following parts of the anaesthetic machine/circuit: i) Expiratory valve ii) Flow meter iii) Oxygen flush iv) Reducing valve v) Vaporiser
- Expiratory valve - a valve which allows the escape of gas in a semi-closed system.
- Flow meter - a calibrated device which controls the amount of gas administered to the patient.
- Oxygen flush - also known as emergency oxygen; delivers fresh oxygen directly to the common gas outlet.
- Reducing valve - a valve sited between the cylinder and flow meter allowing delicate control of the gas flow.
- Vaporiser - an agent specific calibrated device which allows volatile liquid to vaporise; the vapour concentration is adjusted by selecting the desired percentage on the dial.
What is meant by "co-axial" and which circuits possess this property?
Co-axial means a tube within a tube. The Lack and Bain systems are examples of coaxial circuits. In the Lack, the outer limb is inspiratory and surrounds an inner expiratory tube. In the Bain, the outer limb is expiratory whilst the inner is inspiratory.
What is the Magill circuit also known as?
Mapleson A.
In which circuit might a Jackson Rees modification be employed?
Ayres T piece; the Jackson Rees modification is the inclusion of an open ended reservoir bag on the expiratory limb.
List circuits suitable for cats and small dogs.
- Ayres T piece.
- Ayres T piece with Jackson Rees modification.
- Coaxial Lack.
- Bain Mapleson E.
- Bain Mapleson F.
List circuits suitable for medium to large dogs.
- Magill.
- Coaxial Lack.
- Parallel Lack.
- Bain Mapleson D.
- To & Fro system.
- Circle system.
What are the gas flow rates required for closed circuits?
5-10 mls/kg/minute (more than 10mls may be necessary if used as low flow circuits).
What is meant by the term "circuit factor"?
The circuit factor is a term used to describe the amount by which the calculated tidal volume of the patient is multiplied by in order to administer the correct amount of gas. Each type of circuit has its own circuit factor, apart from the closed systems (To & Fro and Circle system) - see Q21.
State the circuit factors for the following circuits: Ayres T piece, Bain (Mapleson D, E and F), Lack, Magill.
- Ayres t piece = 2.5-3
- Bain (Mapleson D, E and F) = 2.5-3
- Lack = 1-1.5
- Magill = 1-1.5
Describe the modified Lack circuit, and explain how it differs to the standard Lack circuit.
There are 2 types of Lack system. The standard Lack consists of a double tube (described as coaxial) through which the animal breathes. The outer tube is the inspiratory limb and connects to a reservoir bag, whilst the inner tube is the expiratory limb. The modified Lack is also known as the parallel Lack and consists of a parallel configuration of the inspiratory and expiratory limbs. This avoids the problems of coaxial systems including disconnection, fracture or kinking of the inner limb.
Nitrous oxide can be safely used in semi-closed (non-re-breathing) circuits, but must be used with caution in closed (re-breathing) circuits. What must be measured if nitrous oxide is employed within a closed circuit and why?
It is essential that the carbon dioxide level of the blood is monitored since hypercapnia (hypercarbia) is a risk.
What is intermittent positive pressure ventilation?
This is a technique used to "breathe" for the patient should natural respiration cease. The rebreathing or reservoir bag is filled with oxygen and squeezed intermittently to fill the patient's lungs. If an open-ended bag is used, the end needs to be occluded. A modest amount of carbon dioxide may be necessary to promote the return of natural breathing.
Describe how the Bain Mapleson D, E and F circuits differ.
- The Mapleson D possesses a closed reservoir bag and is suitable for cats and small dogs.
- The Mapleson E does not possess a reservoir bag and is suitable for animals larger than 10kg.
- The Mapleson F possesses an open-ended reservoir bag and is suitable for animals larger than 10kg.
What is meant by the term "tidal volume"?
Tidal volume is the amount of gas inspired and expired in one breath. It is expressed in mls and is estimated at 10-15mls/kg. Larger animals tend to require 10mls/kg whilst cats and toy breeds require 15mls/kg.
What is meant by the term "minute volume"?
Minute volume is the amount of gas inspired and expired over the duration of one minute. It is expressed in mls which may then be converted to litres. It is calculated by multiplying the TIDAL VOLUME by the respiratory rate.
How would you work out the gas flow rate for a 4kg cat with a respiratory rate of 20 breaths per minute (an Ayres T piece is to be used)?
- First estimate the TIDAL VOLUME which is 10-15mls/kg 15 x 4 = 60mls.
- Next calculate the MINUTE VOLUME (tidal volume x respiratory rate) 60 x 20 = 1200mls or 1.2L.
- Finally multiply the minute volume by the CIRCUIT FACTOR 1.2 x 2.5 = 3L.
How would you work out the gas flow rate for a 20kg dog with a respiratory rate of 10 breaths per minute (a Magill circuit is to be used)?
- First estimate the TIDAL VOLUME which is 10-15mls/kg 10 x 20 = 200mls.
- Next calculate the MINUTE VOLUME (tidal volume x respiratory rate) 200 x 10 = 2000mls or 2L.
- Finally multiply the minute volume by the CIRCUIT FACTOR 2 x 1.5 = 3L.
If nitrous oxide is to be used, what ratios of oxygen to nitrous are suitable?
- 50% Nitrous and 50% Oxygen.
- 66% Nitrous and 33% Oxygen.

Safe Use Of Anaesthetic Equipment

Arlo Guthrie — Tue, 21 Apr 2009 10:28:34 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:28:34

QUESTIONS

How should volatile agents be stored?
How should gas cylinders be stored?
How should anaesthetic circuits be cleaned and stored?
What is the procedure for the cleaning of endotracheal tubes?
Explain the importance of good ventilation and an efficient scavenge system when inhalation agents are employed.
What items should be close to hand on the anaesthetic trolley and why?
List 6 important checks to be made to the anaesthetic machine prior to use.
In addition to your answers to Q7, list 6 actions that should be carried out on a daily basis to maintain equipment used in gaseous anaesthesia.
How should the anaesthetic machine be cleaned?
How frequently should professional servicing of the anaesthetic machine be performed?
Describe a pulse oximeter.
Describe a laryngoscope.
Describe the 4 types of scavenge system in use in veterinary practice; which is the most efficient?
How would you gauge the content of gas cylinders, soda lime canisters, charcoal absorbers and volatile agent levels?
Describe the function of the following parts of the anaesthetic machine/circuit: i) Expiratory valve. ii) Flow meter. iii) Oxygen flush. iv) Reducing valve. v) Vaporiser.
What is meant by "co-axial" and which circuits possess this property?
What is the Magill circuit also known as?
In which circuit might a Jackson Rees modification be employed?
List circuits suitable for cats and small dogs.
List circuits suitable for medium to large dogs.
What are the gas flow rates required for closed circuits?
What is meant by the term "circuit factor"?
State the circuit factors for the following circuits: Ayres T piece, Bain (Mapleson D, E and F), Lack, Magill.
Describe the modified Lack circuit, and explain how it differs to the standard Lack circuit.
Nitrous oxide can be safely used in semi-closed (non-re-breathing) circuits, but must be used with caution in closed (re-breathing) circuits. What must be measured if nitrous oxide is employed within a closed circuit and why?
What is intermittent positive pressure ventilation?
Describe how the Bain Mapleson D, E and F circuits differ.
What is meant by the term "tidal volume"?
What is meant by the term "minute volume"?
How would you work out the gas flow rate for a 4kg cat with a respiratory rate of 20 breaths per minute (an Ayres T piece is to be used)?
How would you work out the gas flow rate for a 20kg dog with a respiratory rate of 10 breaths per minute (a Magill circuit is to be used)?
If nitrous oxide is to be used, what ratios of oxygen to nitrous are suitable?

Types Of Anaesthesia - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:23:36 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:23:36

ANSWERS

Define local anaesthesia.
Local anaesthesia is defined as the reversible blocking of nerve conduction resulting in analgesia of an area of the anatomy; local anaesthetics may be injected or applied topically.
Lignocaine is a commonly used local anaesthetic; list 6 advantageous properties of this drug.
- Good surface analgesia.
- Rapid onset of action.
- Long acting (1-1 and a half hours).
- Effectively spread throughout the body tissue.
- Low toxicity.
- Antiarrythmic.
Describe the signs of local anaesthetic overdose in the order in which they would be seen.
- Sedative effect.
- Twitching.
- Convulsions.
- Coma.
- Death.
Give 2 ways in which local anaesthetic overdose may be avoided.
- Use the minimum dose required to produce an effect.
- Use regional techniques where possible rather than local infiltration.
Why is adrenaline commonly incorporated into local anaesthetic solutions such as Lignocaine?
Local anaesthetics such as Lignocaine cause vasodilation and the subsequent increased blood supply limits analgesic action and increases systemic toxicity. Adrenaline is a vasoconstrictor and opposes this effect.
Why might the hair of a patient change colour at the site of Lignocaine administration, and what other more serious complication may arise?
The vasoconstriction caused by adrenaline may lead to ischaemia (deficiency in the blood supply to a part of the body) which can cause the hair to change colour following subcutaneous or intradermal administration. A more serious complication is necrosis of an area with a limited blood supply such as the teats of the mammary glands.
List 6 preparations of Lignocaine used in veterinary practice.
- Vial for injection.
- Cartridges - used in dental syringes
- Creams and ointments.
- Lubricant gel.
- Aerosol spray.
- Ophthalmic preparations.
What is the active ingredient in Ophthaine, a popular ophthalmic preparation?
Proparacaine.
List the 4 ways in which local anaesthetics are used to produce analgesia and briefly describe each technique.
- Surface local anaesthesia - topical applications used in analgesia of the mucous membranes such as those of the cornea, urethra and larynx.
- Local infiltration - repeated injections of local anaesthetic to a surgical site; a field block avoids interference by adrenaline of wound healing.
- Regional anaesthesia - 3 types:
  i) Conduction block - sterile local anaesthetic is injected into nerves rather than nerve endings; the intercostal nerves may be blocked in this way to provide analgesia following a thoracotomy operation
  
  ii) Spinal analgesia - local anaesthetic is injected into the cerebrospinal fluid filled space below the arachnoid mater
  
  iii) Epidural analgesia - local anaesthetic is injected into the space between the dura mater and the periosteum lining the spinal canal.
- Intravenous regional anaesthesia - a technique used for surgical procedures in limb extremities; an Esmarch bandage is applied to stop arterial blood flow, and local anaesthetic may be injected into any vein distal to the tourniquet.
List 4 surgical procedures in which epidural analgesia may be useful.
- Exploratory laporotomy; especially in toxic patients.
- Caesarean section.
- Hind limb surgery.
- Perineal surgery.
What is the main risk of lumbar epidural analgesia?
Infection; the procedure must be carried out aseptically. Other risks to note include systemic toxicity, respiratory paralysis, spinal cord damage and hypotension.
Give examples of 2 surgical procedures in which intravenous regional analgesia may be useful.
- Removal of an inter-digital foreign body.
- Amputation of a digit.
List 4 local anaesthetic drugs in addition to Lignocaine and Proparacaine.
- Amethocaine - suitable for skin and aural preparations.
- Bupivacaine - four times stronger than Lignocaine, all preparations contain adrenaline.
- Mepivacaine - suitable for conduction blocks in equine species.
- Procaine - good analgesia but poor tissue penetration; unsuitable for regional nerve blocks.
List the 4 main indications for intravenous anaesthesia.
- As the sole agent to facilitate examination or to perform a short surgical procedure.
- As induction for inhalation anaesthesia.
- To supplement inhalation anaesthesia.
- Central nervous system suppression in conditions such as poisoning cases.
What are the advantages of intravenous anaesthesia?
- Simplicity - only a needle and syringe are required for administration.
- Rapid induction - relatively stress-free for a calm or sedated animal.
- Rapid recovery.
- No explosion or pollution hazards (these are a risk of inhalation anaesthesia).
What are the disadvantages of intravenous anaesthesia?
- Rapid induction means that the stages of anaesthesia are not as recognisable as in inhalation techniques and are therefore more difficult to monitor.
- Risk of overdose.
- Unsuitable for major surgery due to the swiftness of recovery.
Intravenous anaesthesia may be given as a single dose, incrementally (repeated top-up injections) or as a continuous infusion. Under which technique will recovery be quickest?
Single dose administration. Incremental doses in particular will prolong the recovery time and may predispose the patient to excitement upon awakening.
Name the vein of choice for intravenous anaesthetic administration and list 2 other veins which would be suitable if this vein was inaccessible.
The cephalic (radial) vein is preferred since the animal is restrained in such a way that the airway can easily be observed. Other suitable veins are the saphenous (recurrent tarsal vein) or the jugular.
How do injectable anaesthetics work to produce unconsciousness?
The brain, with its rich blood supply, receives a high concentration of anaesthetic drug shortly after intravenous injection. Unconsciousness occurs once a critical concentration has been exceeded, while organs that are less well perfused take up the drug later (redistribution). Movement of the drug from the brain to the plasma takes place due to a diffusion gradient created by falling plasma levels.
Define barbiturates, and give 2 examples of drugs of this kind commonly used as veterinary anaesthetic agents.
Barbiturates are a large group of sedative and hypnotic drugs derived from barbituric acid. Most are controlled drugs under Schedule 3 of the Misuse of Drugs Act 1971 and Misuse of Drugs Regulations 1985. 2 examples are:
- Methohexitone sodium (Brietal).
- Pentobarbitone sodium (Sagatal).
- Thiopentone sodium (Intraval, Thiovet).
If thiopentone sodium is accidentally injected outside of a vein, severe skin sloughing may occur; why is this, and what should be done if extravasation occurs?
Thiopentone sodium is very alkaline (pH 14) and irritant, particularly if used in concentrations of greater than 2.5%. Should extravasation occur, the area around the vein must be injected with sterile water immediately to dilute the concentration of the thiopentone.
Why is pentobarbitone sodium not recommended as a sole anaesthetic agent?
Pentobarbitone sodium is a long-acting drug producing both prolonged induction and recovery. Hypothermia is common, and both respiratory and cardiovascular depression are marked; therefore oxygen must be available to animals given this agent.
Note: Its therapeutic index is very low therefore a small overdose can have fatal consequences.
Give an example of a steroid anaesthetic drug and explain why it is unsafe to use in dogs.
Alphaxolone (Saffan) is an example of a steroid anaesthetic. In many practices it is the intravenous agent of choice for cats since it produces rapid induction and recovery, and also has a better safety margin than barbiturates. Saffan is not recommended for use in dogs since the cremaphor EL (polyoxyethylated castor oil used to help dissolve the steroids within the solution) elicits histamine release with all the signs of anaphylaxis which can be fatal.
What is the main disadvantage of steroid anaesthetics other than that they cannot be safely used in dogs?
Mild anaphylactic reactions can occur in cats including the swelling of the pinnae and paws. Very occasionally, fatal pulmonary oedema may occur.
Give an example of a dissociative anaesthetic drug in the cyclohexanone group and explain what is meant by dissociative.
Ketamine is an example of a dissociative agent commonly used in veterinary practice. It is usually administered by intramuscular injection and produces a state of profound analgesia with superficial sleep. The eyes remain open, and palpebral, pedal, laryngeal and pharyngeal reflexes are present. The patient is often hypersensitive to sound.
What precautions must be taken when ketamine is used?
- Constant careful monitoring - due to the unique state of anaesthesia produced, depth may be difficult to assess.
- Ophthalmic ointment - the patient's eyes require protection and lubrication since they remain open and "awake" during the procedure and the cornea may become dry.
- Warmth - ketamine produces hypothermia.
Why is ketamine alone unsuitable for dogs?
Ketamine used as a sole agent in dogs has been found to increase muscle activity to a level of convulsions. Excessive muscle tone or movement in cats may be controlled by the administration of a barbiturate at one quarter of the induction dose.
List the drugs that may be given in combination with Ketamine to improve its anaesthetic effects.
- ACP - sedation and prolonged anaesthetic effect.
- Atropine - to prevent salivation.
- Barbiturates - to prevent excessive muscle tone or movement.
- Diazepam - for a smooth, slow induction in debilitated patients.
- Midazolam.
- Medetomidine (Domitor) - Prolonged effect; Atipamezole (Antisedan) may be used to antagonise the effects.
- Xylazine - for sedation and muscle relaxation.
  Ketamine with Diazepam and Xylazine have anti-convulsant effects rendering them safe combinations to use in dogs.
Give an example of an anaesthetic drug of the phenol group, and state the breed of dog in which this is the intravenous anaesthetic of choice.
Propofol (Rapinovet) is an example of an anaesthetic drug of the phenol group. It may be used in both cats and dogs, and is especially useful in greyhounds who suffer a remarkably long recovery from thiopentone sodium (Intraval, Thiovet). This is due to a lack of body fat for redistribution of thiopentone.
Give 4 advantages of propofol.
- Produces rapid unconsciousness.
- Produces rapid recovery.
- Incremental injections (oxygen to be given) do not prolong recovery.
- Rapid hepatic metabolism; non-cumulative.
Give 4 disadvantages of propofol.
- Respiratory depression.
- Hypotension.
- Expensive, and contains no bacteriostat, so unopened vials must be discarded.
- Special care required if administered to animals with liver disease (due to rapid hepatic metabolism).
Pentobarbitone is an old-fashioned intravenous anaesthetic agent largely superseded by safer, more recent drugs. It does have a place in veterinary practice however; what are its uses?
Pentobarbitone is still sometimes used as an anaesthetic agent (usually in laboratory animals). Both induction and recovery are prolonged due to the delay in the drug crossing the blood-brain barrier. Nowadays, it is most commonly used as an anticonvulsant drug or for euthanasia.
What is the main advantage of inhalation anaesthesia.
Inhalation anaesthesia is a relatively safe technique since the animal is usually intubated (unless a mask is used) thus protecting and preserving the airway. Oxygen may be administered and intermittent positive pressure ventilation may be performed in the event of apnoea.
List the 4 gaseous agents used in inhalation anaesthesia and briefly describe their uses.
- Carbon dioxide (grey cylinder) - used to produce normocapnia in controlled breathing when blood-gas analysis unavailable, also used to increase the depth of anaesthesia when volatile agents are employed and to stimulate the onset of breathing after a period of intermittent positive pressure ventilation.
- Cyclopropane (orange cylinder) - no longer used in veterinary practice since it is highly inflammable.
- Nitrous oxide (blue cylinder) - a sweet-smelling potent analgesic with anaesthetic sparing effects used as a carrier gas; its inclusion also preserves cardiopulmonary performance and accelerates the induction of anaesthesia.
- Oxygen (black cylinder with white neck) - used as a carrier gas in inhalation anaesthesia; also used in cases where normal delivery of atmospheric oxygen is threatened and during recovery from anaesthesia until a patient is able to maintain haemoglobin concentration with room air.
Nitrous oxide is often used as a carrier gas due to its analgesic and anaesthetic sparing effects; it does however possess certain disadvantages most notably diffusion hypoxia and gas filled viscus. Describe these terms.
- Diffusion hypoxia = when delivery of nitrous oxide ends, the direction of diffusion reverses (from blood into the alveolar space); this means that alveolar oxygen may be diluted, and therefore the animal requires pure oxygen (100%) rather than room air (20%) for at least 3 minutes after termination of nitrous oxide delivery to prevent hypoxia.
- Gas filled viscus = nitrous oxide is relatively insoluble in blood and therefore accumulates in gas-filled organs such as the dilated stomach of a dog with gastric dilation; the pressure is increased within such spaces and hence compromises the patient.
What is meant by the "open method" and "semi-open method" of anaesthesia? Why are these techniques not commonly used today?
Open method = volatile anaesthetic is placed onto absorbent material which is held near to the animal's nose and inhaled.
Semi-open method = volatile anaesthetic is placed onto absorbent material held within a mask through which the animal inhales.
Both techniques possess the following disadvantages:
- Pollution since no scavenge system is employed.
- Depth of anaesthesia is difficult to control.
- Hypoxia and hypercapnia are common.
- Resuscitation is difficult.
- Patient resistance during induction.
Give 2 examples of closed anaesthetic circuits.
- The circle system.
- Water's canister (also known as the to and fro system).
  These circuits are described in Revision Module 6 - The Safe Use of Anaesthetic Equipment.
List 4 advantages of closed anaesthetic circuits (also known as re-breathing systems).
- Efficient removal of carbon dioxide (particularly with the circle system).
- Economic use of oxygen and volatile agent.
- Low explosion and pollution hazards.
- Heat and moisture conservation.
List 4 disadvantages of closed anaesthetic circuits.
- Cumbersome; may prove obstructive in head or oral surgery.
- Resistance and dead space from the presence of soda lime (and valves in the circle system, making it unsuitable for use in animals under 10 kg).
- Level of anaesthesia slow to change.
- Nitrous oxide cannot be safely used and de-nitrogenation must be regularly performed.
Give 4 examples of semi-closed anaesthetic circuits.
- Ayres.
- Bain.
- Lack.
- Magill.
  These circuits are described in Revision Module 6 - The Safe Use of Anaesthetic Equipment.
List 4 advantages of semi-closed anaesthetic circuits.
- Low resistance.
- Level of anaesthesia rapidly changed.
- Nitrous oxide can be safely used.
- Denitrogenation not required.
List 4 disadvantages of semi-closed anaesthetic circuits.
- High gas flow requirements.
- High volatile agent consumption
- Loss of expired moisture and heat.
- Different flow rates are required for different circuits.
Give 4 examples of volatile anaesthetic agents and briefly describe their properties.
- Enflurane - Administered via an "Enfluratec" vaporiser; sweet smelling, reasonably potent anaesthetic producing fair muscle relaxation and a rapid, smooth recovery; expensive.
- Halothane - Administered via a "Fluotec" vaporiser; sweet smelling, potent anaesthetic producing good muscle relaxation; the most popular volatile agent in practice at present.
- Isofluorane - Administered via a "Fluotec" vaporiser; pungent anaesthetic producing good muscle relaxation and analgesia, useful for cardiac conditions as causes less cardiac depression than Halothane; may produce some transient excitable effects after painful surgery, expensive.
- Metofane - Administered via a "Pentec" vaporiser; fruity smelling anaesthetic producing good muscle relaxation; not suitable for induction.
What is the purpose of soda lime?
Soda lime crystals are contained within a canister incorporated into a closed anaesthetic circuit. They contain:
- 90% Calcium hydroxide.
- 5% Sodium hydroxide.
- 1% Potassium hydroxide.
- Silicates to prevent powdering.
  The hydroxides combine with carbon dioxide in the presence of moisture to form carbonates, thus allowing the re-breathing of expired air. Soda lime crystals change colour when spent (pink to white, or white to mauve) and it is important to renew the used crystals when indicated to avoid hypercapnia and hypoxia.
What is a fluabsorber?
A fluabsorber is a canister containing activated charcoal for the purpose of removal of waste anaesthetic gases. It is attached to the scavenge valve via a pipe and is useful in portable anaesthetic machines where it may not be possible to employ a more efficient type of scavenge system. However, activated charcoal cannot remove nitrous oxide and should not therefore be used in conjunction with this gas. Fluabsorbers have a limited life and should be weighed regularly to ensure that spent canisters are replaced at once.
What is neuromuscular blockade, and list examples of neuromuscular blocking agents describing their properties.
Neuromuscular blockade is the employment of muscle relaxants as a supplement to general anaesthesia. Absolute relaxation is achieved by the action of these agents upon the nicotinic receptors at the neuromuscular junction. Muscle relaxants are not anaesthetics, and do not possess analgesic properties. They paralyse the respiratory muscles and should therefore only be used when facilities for positive pressure ventilation are available. They are useful in cases such as intra-abdominal surgery and open chest surgery, but care must be taken since the depth of anaesthesia is difficult to monitor since reflex response is suppressed and spontaneous respiration abolished. There are 2 types of muscle relaxant; depolarising and non-depolarising. These are listed below:
- Depolarising = Succinylcholine; a short acting relaxant with a rapid onset time used to facilitate endotracheal intubation in cats.
- Non-depolarising = Alcuronium, Atracurium, Gallamine, Pancuronium and Vecuronium; these relaxants are intermediate to long acting and are used in surgical cases.

Types Of Anaesthesia

Arlo Guthrie — Tue, 21 Apr 2009 10:22:40 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:22:40

QUESTIONS

Define local anaesthesia.
Lignocaine is a commonly used local anaesthetic; list 6 advantageous properties of this drug.
Describe the signs of local anaesthetic overdose in the order in which they would be seen.
Give 2 ways in which local anaesthetic overdose may be avoided.
Why is adrenaline commonly incorporated into local anaesthetic solutions such as Lignocaine?
Why might the hair of a patient change colour at the site of Lignocaine administration, and what other more serious complication may arise?
List 6 preparations of Lignocaine used in veterinary practice.
What is the active ingredient in Ophthaine, a popular ophthalmic preparation?
List the 4 ways in which local anaesthetics are used to produce analgesia and briefly describe each technique.
List 4 surgical procedures in which epidural analgesia may be useful.
What is the main risk of lumbar epidural analgesia?
Give examples of 2 surgical procedures in which intravenous regional analgesia may be useful.
List 4 local anaesthetic drugs in addition to Lignocaine and Proparacaine.
List the 4 main indications for intravenous anaesthesia.
What are the advantages of intravenous anaesthesia?
What are the disadvantages of intravenous anaesthesia?
Intravenous anaesthesia may be given as a single dose, incrementally (repeated top-up injections) or as a continuous infusion. Under which technique will recovery be quickest?
Name the vein of choice for intravenous anaesthetic administration and list 2 other veins which would be suitable if this vein was inaccessible.
How do injectable anaesthetics work to produce unconsciousness?
Define barbiturates, and give 2 examples of drugs of this kind commonly used as veterinary anaesthetic agents.
If thiopentone sodium is accidentally injected outside of a vein, severe skin sloughing may occur; why is this, and what should be done if extravasation occurs?
Why is pentobarbitone sodium not recommended as a sole anaesthetic agent?
Give an example of a steroid anaesthetic drug and explain why it is unsafe to use in dogs.
What is the main disadvantage of steroid anaesthetics other than that they cannot be safely used in dogs?
Give an example of a dissociative anaesthetic drug in the cyclohexanone group and explain what is meant by dissociative.
What precautions must be taken when ketamine is used?
Why is ketamine alone unsuitable for dogs?
List the drugs that may be given in combination with Ketamine to improve its anaesthetic effects.
Give an example of an anaesthetic drug of the phenol group, and state the breed of dog in which this is the intravenous anaesthetic of choice.
Give 4 advantages of propofol.
Give 4 disadvantages of propofol.
Pentobarbitone is an old-fashioned intravenous anaesthetic agent largely superseded by safer, more recent drugs. It does have a place in veterinary practice however; what are its uses?
What is the main advantage of inhalation anaesthesia.
List the 4 gaseous agents used in inhalation anaesthesia and briefly describe their uses.
Nitrous oxide is often used as a carrier gas due to its analgesic and anaesthetic sparing effects; it does however possess certain disadvantages most notably diffusion hypoxia and gas filled viscus. Describe these terms.
What is meant by the "open method" and "semi-open method" of anaesthesia? Why are these techniques not commonly used today?
Give 2 examples of closed anaesthetic circuits.
List 4 advantages of closed anaesthetic circuits (also known as re-breathing systems).
List 4 disadvantages of closed anaesthetic circuits.
Give 4 examples of semi-closed anaesthetic circuits.
List 4 advantages of semi-closed anaesthetic circuits.
List 4 disadvantages of semi-closed anaesthetic circuits.
Give 4 examples of volatile anaesthetic agents and briefly describe their properties.
What is the purpose of soda lime?
What is a fluabsorber?
What is neuromuscular blockade, and list examples of neuromuscular blocking agents describing their properties.

Understanding Analgesic Drugs - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:21:31 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:21:31

ANSWERS

Define analgesia.
Insensibility to pain; especially the relief of pain without causing unconsciousness.
Why are analgesic drugs often administered as part of a patient's premedication?
An animal is usually anaesthetised for the purpose of enabling surgery in a humane manner. Surgery of any kind is generally painful in varying degrees, and therefore analgesia promotes a more comfortable induction and recovery for the patient. Other drugs used in anaesthesia (sedatives, induction agents and volatile gases) may possess poor analgesic properties, thus indicating a need for additional pain relief.
There are 2 main analgesic drug groups; state them, giving 2 common examples of each that are used in veterinary practice.
- Narcotic analgesics (opioids) - pethidine and morphine.
- Non-steroidal anti-inflammatory drugs (NSAIDS) - aspirin and ketoprofen.
Most narcotic analgesics are schedule 2 controlled drugs; which regulations control their purchase and use?
The Misuse of Drugs Act 1971 and the Misuse of Drugs Regulations 1985.
In addition to pethidine and morphine, list 3 other narcotic analgesics.
- Fentanyl (Sublimaze).
- Papaveretum (Omnopen).
- Buprenorphine (Vetergesic)
  NB. Fentanyl is not used in cats.
Why are narcotic analgesics unpredictable?
They possess both stimulant and depressant actions on the central nervous system. The result depends upon the dose, species and presence or absence of pain.
What adverse effects may arise in a patient stimulated by the administration of a narcotic analgesic?
- Defecation.
- Vomiting.
What serious side effect is unavoidably linked with analgesia, and particularly narcotic drugs?
Respiratory depression. The cough reflex is also suppressed which may prove problematic.
Why is pethidine preferred in cases of moderate pain over morphine?
Pethidine does not cause excitement reactions, and defecation and vomiting are rare. Its mild anticholinergic properties and resultant spasmolytic effect make it a useful drug for patients suffering intestinal pain.
List 3 conditions in which the administration of morphine would be contraindicated.
- Acute pancreatitis.
- Biliary obstruction.
- Head injuries (they may increase intra-cranial pressure).
List 5 conditions in which the use of opioids may be indicated.
- Opioids are the preferred treatment in cases of severe pain following trauma or surgery. Some examples are listed:
- Fractures (but not of the skull - see Q10).
- Thermal burns.
- Aural ablation.
- Cruciate repair.
- Femoral head arthroplasty.
Define a partial agonist and give an example.
A partial agonist is an antagonistic drug with sufficient agonist properties to enable its use as an analgesic. Buprenorphine (Vetergesic) is an example and is popular due to its long-lasting effect.
For what reasons are narcotic antagonists used?
- To antagonise analgesia in the event of adverse side effects.
- To antagonise analgesia post surgery for a faster recovery.
- Reduction of respiratory depression.
- First aid measure in the event of self-administration.
Give 2 examples of narcotic antagonists.
- Naloxone (Narcan).
- Diprenorphine (Revivon).
Neuroleptanalgesia provides a combination of deep sedation and analgesia by a synergistic combination of a neurolept and a narcotic analgesic; what is the purpose of the neurolept?
To counteract the unpleasant side effects of the narcotic analgesic, particularly excitement reactions and vomiting.
Neuroleptanalgesia is described in Revision Module 3 - Understanding the Use of Premedicant Drugs.
Non-steroidal anti-inflammatory drugs (NSAIDS) should not be used in cases of acute pain; when might their administration be indicated?
- Analgesia in cases of relatively mild, chronic pain (eg. osteoarthritis, osteochondritis).
- Post operative analgesia following on from that provided under general anaesthesia.
Why is accurate dosage extremely important when administering NSAIDS?
NSAIDS may prove nephrotoxic to cats and dogs.
Which anaesthetic gas has analgesic properties?
Nitrous oxide.
Which volatile anaesthetic has analgesic properties; and when is its use contraindicated?
Methoxyfluorane (Metofane) provides effective, long lasting analgesia. However, it should not be used in animals receiving NSAIDS. An alternative volatile anaesthetic may be selected or the NSAIDS witheld.
The alpha agonists possess good analgesic properties; give 2 examples.
- Xylazine (Rompun).
- Medetomidine (Domitor).
What is meant by sequential analgesia?
Sequential analgesia is a technique employed to reduce the adverse side-effects of analgesia; low doses of drugs are administered from groups acting at different levels on the pain pathway.
Why are post-operative analgesics ideally administered before recovery begins?
Drugs such as opioids are slow acting and it may be up to 30 minutes before they take effect. It is believed that the quality and duration of pain relief is improved if analgesics are administered pre-emptively (ie. before the animal wakes up and appreciates pain).
List behavioural signs that may indicate that an animal is in pain.
- Aggression.
- Anxiety.
- Diminished response to stimuli.
- Cringing.
- Huddling.
- Panting.
- Praying position.
- Shivering.
- Vocalising.
- Wound interference.
List clinical signs that may indicate that an animal is in pain.
- Anorexia.
- Constipation.
- Hypertension or hypotension.
- Incontinence.
- Lameness.
- Pyrexia.
- Tachycardia.
- Tachypnoea.
In addition to the administration of analgesic drugs, describe some further ways in which a patient may be made more comfortable.
- Provide plenty of soft, comfortable bedding.
- Confinement (particularly following orthopaedic surgery).
- Immobilisation (of a joint for example following a fracture).
- Physiotherapy.
- Provide assistance with grooming and cleaning.
- Ensure that the animal receives optimal nutrition in order to promote the growth of healthy tissue.
- Keep dressings clean and dry and prevent any wound interference.
- Provide a warm environment for recovery.
- Make sure that the surroundings are suitable; a shocked animal will recuperate better in a calm and quiet atmosphere, while a lively animal may appreciate lots of activity to prevent boredom.
- Assist with urination and defecation if necessary.
- Provide support slings for animals with walking difficulties.
- Always treat your patients with kindness and respect, and ensure that handling is carried out gently taking particular care over any painful area.

Understanding Analgesic Drugs

Arlo Guthrie — Tue, 21 Apr 2009 10:20:42 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:20:42

QUESTIONS

Define analgesia.
Why are analgesic drugs often administered as part of a patient's premedication?
There are 2 main analgesic drug groups; state them, giving 2 common examples of each that are used in veterinary practice.
Most narcotic analgesics are schedule 2 controlled drugs; which regulations control their purchase and use?
In addition to pethidine and morphine, list 3 other narcotic analgesics.
Why are narcotic analgesics unpredictable?
What adverse effects may arise in a patient stimulated by the administration of a narcotic analgesic?
What serious side effect is unavoidably linked with analgesia, and particularly narcotic drugs?
Why is pethidine preferred in cases of moderate pain over morphine?
List 3 conditions in which the administration of morphine would be contraindicated.
List 5 conditions in which the use of opioids may be indicated.
Define a partial agonist and give an example.
For what reasons are narcotic antagonists used?
Give 2 examples of narcotic antagonists.
Neuroleptanalgesia provides a combination of deep sedation and analgesia by a synergistic combination of a neurolept and a narcotic analgesic; what is the purpose of the neurolept?
Non-steroidal anti-inflammatory drugs (NSAIDS) should not be used in cases of acute pain; when might their administration be indicated?
Why is accurate dosage extremely important when administering NSAIDS?
Which anaesthetic gas has analgesic properties?
Which volatile anaesthetic has analgesic properties; and when is its use contraindicated?
The alpha agonists possess good analgesic properties; give 2 examples.
What is meant by sequential analgesia?
Why are post-operative analgesics ideally administered before recovery begins?
List behavioural signs that may indicate that an animal is in pain.
List clinical signs that may indicate that an animal is in pain.
In addition to the administration of analgesic drugs, describe some further ways in which a patient may be made more comfortable.

Understanding Premedicant Drugs - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:19:17 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:19:17

ANSWERS

List 4 reasons for anaesthetic premedication.
- To relax the patient, particularly during induction which may prove traumatic.
- Pain relief.
- Anaesthetic sparing effect.
- Reduction of the undesirable side effects of anaesthesia such as salivation and vomiting.
List 5 drug classes often employed as premedicants.
- Analgesics (pain relievers).
- Hypnotics (arousable sleep inducing agents).
- Parasympathetic antagonists (anticholinergic drugs; agents that oppose the effects of the parasympathetic nervous system).
- Sedatives (calming agents that cause drowsiness).
- Tranquillisers (calming agents that do not cause drowsiness).
As with general anaesthetic drugs, premedicants need to be chosen with care. The choice of drug and the dose rate should be selected in accordance with the requirements of the individual. List aspects to be considered with regard to premedication.
- Age - age-related illnesses may mean that an animal is less able to metabolise certain drugs.
- General condition - obese, dehydrated, malnourished and depressed patients all require extra vigilance.
- Temperament - highly excitable terriers may prove resistant to drugs such as ACP.
- Breed - some breeds may experience adverse effects with some premedicants; e.g. syncope (fainting) often occurs in Boxers given ACP.
- Pain - pre-operative analgesia should be given if necessary; this also exerts an effect during surgery and the post-operative period.
- Type of anaesthesia proposed - the length and complexity of surgery are also important in addition to choice of anaesthetic agent/s.
- Post-operative requirements - an animal recovering from major surgery will need to be kept as calm and pain-free as possible during recovery, while a routine op such as a grass seed removal from the ear canal will require a patient to be up and about as soon as practicable.
- Complications - these may include prolonged recoveries, adverse drug reactions, vomiting and pre-existing disease.
- Pregnancy - certain drugs may cross the placenta causing adverse effects to the foetuses.
How is it possible to maximise the effects of sedatives or tranquillisers without increasing the drug dose?
By keeping the patient calm and quiet; avoid excessive petting and stimulation. Cats should be kept out of the way of barking dogs. Each individual should be kennelled in a comfortable, secure cage spacious enough to allow the animal to stand up and turn around.
What is another name sometimes given to tranquillisers?
Ataractic drugs.
One of the reasons for the administration of premedicants is to decrease anxiety in the patient. What group of compounds are lowered in order to achieve this effect?
Catecholamines; including dopamine, adrenaline and noradrenaline. These stimulate the sympathetic nervous system.
What is a parasympathetic antagonist, and give 3 examples that may be used in veterinary practice?
A parasympathetic antagonist is an agent that opposes the effects of the parasympathetic nervous system. These drugs are also known as anticholinergic or antimuscarinic agents. Common examples are:
- Atropine sulphate (Atricare).
- Glycopyrronium bromide (Glycopyrrolate).
- Hyoscine (Scopolamine).
What are the advantageous properties of using parasympathetic antagonists as premedicant drugs?
- Bronchodilation (reduces airway resistance).
- Reduction of salivation.
- Reduction of bronchial secretions.
- Prevention of excessive vagal slowing of the heart (bradycardia as caused by acepromazine).
- Prevention of the muscarinic effects of certain drugs.
List some disadvantageous properties of parasympathetic antagonists.
- Increased metabolic rate.
- Increased heart rate (hence contra-indicated in patients with pre-existing tachycardia).
- Increased myocardial oxygen consumption.
- Arrythmogenic properties (may cause bradyarrythmias or tachyarrythmias).
- May cause gastrointestinal ileus (failure of peristalsis causing intestinal obstruction).
- Possibility of peripheral airway collapse due to viscidification of bronchial secretions.
Acepromazine (ACP) is a commonly used example of the phenothiazine drug group. It is a popular drug due to its safety and does not cause coma if an overdose occurs. List 6 additional advantages of its use as a premedicant.
- Tranquillising and sedative effects.
- Anti-emetic properties (prevents nausea or sickness).
- Spasmolytic properties (reduces discomfort from gastrointestinal spasm).
- Antihistamine action (very weak).
- Synergism (improves the effect of opioids).
- Antiarrythmic in low doses.
Acepromazine (ACP) has several possible adverse side-effects. These are mainly due to the effect of ACP on the nerves that release noradrenaline causing adrenergic block. This may result in hypotension, excessive vagal tone and bradycardia. For these reasons it is undesirable to administer ACP to certain patients. In which animals is it undesirable to administer ACP and why?
- Boxers - ACP may cause syncope (fainting) in Boxers who are exceedingly sensitive to this agent; other breeds may also prove particularly susceptible.
- Hypovolaemic patients - ACP may cause a severe response including a dramatic fall in blood pressure and cardiovascular collapse.
List some further disadvantages of acepromazine, which whilst controllable and not necessarily life-threatening do require attention.
- No analgesic properties (if pain relief is required, opioids are often administered as part of the premedication).
- Hypothermia.
- Poor muscle relaxation.
- Long acting (4-6 hours) with a slow onset (peaks at 10-20 minutes).
- Unpredictable (terriers and aggressive dogs are often resistant).
Acepromazine has both tranquillising and sedative properties. Given in very low doses, it tranquillises without sedation; whilst moderate doses promote moderate sedation (although not in resistant animals!). Why is it undesirable to administer high doses of acepromazine?
The dose-response relationship of acepromazine for sedation levels out rapidly. This means that after a certain point, a higher dose will only increase the side- effects of the drug and not the level of sedation.
In addition to acepromazine, list 3 other phenothiazines used in veterinary practice.
- Chlorpromazine (Largactil).
- Promazine (Sparine).
- Trimeprazine (Vallergan).
Opioids (narcotic analgesics) are often used in conjunction with other drugs such as acepromazine in order to provide a synergistic combination of analgesia and sedation. Why must the same degree of care be given to patients administered with this drug combination as for general anaesthesia?
Profound sedation is achieved, and respiratory depression may occur. The patient should be intubated and a supply of oxygen must be available for such cases. Commercially prepared drug combinations of this kind are called neuroleptanalgesics. Hypnorm is a common example used in veterinary practice.
What legislations control the use of opioid analgesics?
The Misuse of Drugs Act 1971 and the Misuse of Drugs Regulations 1985. Opioid analgesics are classified as Schedule 2 drugs; by law they must be kept in a locked receptacle and each use recorded in a controlled drug register.
Opioid analgesics are covered more fully in Revision Module 4 - Understanding the Use of Analgesic Drugs.
Butyrophenones are similar in behaviour to phenothiazines, but none are licensed for veterinary use. Drugs such as droperidol and fluanisone are however available in commercial neuroleptanalgesic mixtures. What advantages exist in the use of such combinations?
- Synergism - lower doses of sedative and analgesic may therefore be used, thus reducing side-effects.
- Butyrophenones have a potent action in reducing opiate-induced vomiting.
What is the name of the common commercial neuroleptanalgesic used very successfully in rabbits and guineapigs?
Hypnorm.
Give 2 advantages of Hypnorm as a premedicant drug.
- Deep sedation.
- Excellent analgesia.
In which cases would the administration of Hypnorm be contraindicated and why?
- Animals with respiratory disease - Hypnorm produces variable respiratory depression.
- Animals with advanced renal and liver failure - Hypnorm is not easily metabolised by such patients.
What is the name of the narcotic antagonist that reverses the effects of Hypnorm?
Naloxone (Narcan).
Naloxone may also be used to reverse the effects of Immobilon.
Give 2 examples of alpha agonists commonly used in veterinary practice.
- Xylazine.
- Medetomidine (Domitor).
What is the name of the drug used to antagonise the effects of medetomidine (Domitor), and why is its use desirable?
Atipamezol (Antisedan). The use of atipamezol is advantageous since the prolonged effect of medetomidine may predispose the patient to hypothermia and hypostatic pneumonia.
If a painful procedure is carried out, it may be advisable to withold the use of atipamazole, or provide pain relief with another analgesic since the animal may be in considerable discomfort if aroused early.
High doses of alpha agonists produce basal narcosis; describe this condition.
Basal narcosis is defined as a state of unconsciousness produced prior to anaesthesia.
In addition to basal narcosis, list 4 other advantages of the alpha agonists.
- Profound, dose dependent sedation.
- Prolonged circulation time which accelerates the uptake of volatile anaesthetic agents; thus producing a marked drug sparing effect.
- Muscle relaxation; Ketamine (a popular dissociative agent) causes muscle rigidity when used alone and is therefore often used in combination with an alpha agonist to ease this stiffness.
  Remember though that muscle relaxation is not always advantageous; this may result in respiratory obstruction in brachycephalic breeds.
- Visceral analgesia.
List 6 disadvantages of alpha agonists.
- Cardiovascular depression (hypertension, hypotension, bradycardia and hypoventilation result).
- Respiratory depression (pallid mucous membranes and apnoeic pauses are not uncommon).
- Emetic effect; always undesirable in an unconscious animal due to the risk of inhalation pneumonia and asphyxia.
- Impaired thermoregulation.
- Reduced or abolished gut motility; therefore unsuitable for use in barium contrast radiography of the digestive tract.
- Aerophagia (excessive swallowing of air); therefore not recommended in breeds predisposed to gastric dilation.
The benzodiazepines which include diazepam (Valium) and midazolam are often used in premedication due to their muscle relaxant effects and tranquillising properties. Give 2 other important advantages of these drugs.
- Safety - high therapeutic indices mean that overdose is uncommon.
- Drug sparing effect - particularly after oral administration.
List 2 other uses of diazepam in addition to premedication.
- Anticonvulsant - used in the treatment of epilepsy.
- Appetite stimulant - may be used in partially anorexic cats to improve the desire to eat.
List 4 disadvantages of diazepam.
- Painful upon injection (unless diazemuls is used intravenously).
- Risk of thrombophlebitis.
- Unpredictable effects - diazepam may stimulate rather than sedate, causing ataxia and often violent struggles.
- Drug formulation - diazepam binds to polyvinyl chloride (the material of which plastic syringes are usually made); use drawn up preparations immediately or syringes of an alternative material.
What is the name of the most common benzodiazepine antagonist?
Flumazenil.
Finally, a word about the commercial neuroleptanalgesic "Immobilon". This powerful drug combination produces deep sedation, hypnosis and profound analgesia, however it also results in severe respiratory depression. What species is very susceptible to Immobilon and what precautions should be taken if it is used?
Immobilon is VERY dangerous to man. It must never be used unless an antagonist is available (Naloxone = Narcan or diprenorphine = Revivon). Self injection may prove fatal if the effects are not reversed, and it must be appreciated that self absorption through cuts or mucous membranes can also be lethal. Utmost care should be taken when disposing of used needles and syringes.

Understanding Premedicant Drugs

Arlo Guthrie — Tue, 21 Apr 2009 10:18:24 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:18:24

QUESTIONS

List 4 reasons for anaesthetic premedication.
List 5 drug classes often employed as premedicants.
As with general anaesthetic drugs, premedicants need to be chosen with care. The choice of drug and the dose rate should be selected in accordance with the requirements of the individual. List aspects to be considered with regard to premedication.
How is it possible to maximise the effects of sedatives or tranquillisers without increasing the drug dose?
What is another name sometimes given to tranquillisers?
One of the reasons for the administration of premedicants is to decrease anxiety in the patient. What group of compounds are lowered in order to achieve this effect?
What is a parasympathetic antagonist, and give 3 examples that may be used in veterinary practice?
What are the advantageous properties of using parasympathetic antagonists as premedicant drugs?
List some disadvantageous properties of parasympathetic antagonists.
Acepromazine (ACP) is a commonly used example of the phenothiazine drug group. It is a popular drug due to its safety and does not cause coma if an overdose occurs. List 6 additional advantages of its use as a premedicant.
Acepromazine (ACP) has several possible adverse side-effects. These are mainly due to the effect of ACP on the nerves that release noradrenaline causing adrenergic block. This may result in hypotension, excessive vagal tone and bradycardia. For these reasons it is undesirable to administer ACP to certain patients. In which animals is it undesirable to administer ACP and why?
List some further disadvantages of acepromazine, which whilst controllable and not necessarily life-threatening do require attention.
Acepromazine has both tranquillising and sedative properties. Given in very low doses, it tranquillises without sedation; whilst moderate doses promote moderate sedation (although not in resistant animals!). Why is it undesirable to administer high doses of acepromazine?
In addition to acepromazine, list 3 other phenothiazines used in veterinary practice.
Opioids (narcotic analgesics) are often used in conjunction with other drugs such as acepromazine in order to provide a synergistic combination of analgesia and sedation. Why must the same degree of care be given to patients administered with this drug combination as for general anasethesia?
What legislations control the use of opioid analgesics? The Misuse of Drugs Act 1971 and the Misuse of Drugs Regulations 1985.
Butyrophenones are similar in behaviour to phenothiazines, but none are licensed for veterinary use. Drugs such as droperidol and fluanisone are however available in commercial neuroleptanalgesic mixtures. What advantages exist in the use of such combinations?
What is the name of the common commercial neuroleptanalgesic used very successfully in rabbits and guineapigs?
Give 2 advantages of Hypnorm as a premedicant drug.
In which cases would the administration of Hypnorm be contraindicated and why?
What is the name of the narcotic antagonist that reverses the effects of Hypnorm?
Give 2 examples of alpha agonists commonly used in veterinary practice.
What is the name of the drug used to antagonise the effects of medetomidine (Domitor), and why is its use desirable?
High doses of alpha agonists produce basal narcosis; describe this condition.
In addition to basal narcosis, list 4 other advantages of the alpha agonists.
List 6 disadvantages of alpha agonists.
The benzodiazepines which include diazepam (Valium) and midazolam are often used in premedication due to their muscle relaxant effects and tranquillising properties. Give 2 other important advantages of these drugs.
List 2 other uses of diazepam in addition to premedication.
List 4 disadvantages of diazepam. ·
What is the name of the most common benzodiazepine antagonist?
Finally, a word about the commercial neuroleptanalgesic "Immobilon". This powerful drug combination produces deep sedation, hypnosis and profound analgesia, however it also results in severe respiratory depression. What species is very susceptible to Immobilon and what precautions should be taken if it is used?

Risk Assessment Of Patient For Anaesthesia - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:17:23 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:17:23

ANSWERS

What is the purpose of pre-operative assessment?
Pre-operative assessment is an essential consultation that should be undertaken with both patient and owner present; the purpose of which is to determine the animal's state of health and to minimise the risk of untoward events during anaesthesia and surgery. It is the responsibility of the veterinary surgeon to perform this assessment, but the veterinary nurse may assist in the following ways:
- Recording data.
- Ensuring that the consent form for anaesthesia and surgical procedure/s is signed (this is a legal requirement).
- Restraint of the patient for examination
- Performance of specific tasks under the direction of the veterinary surgeon such as pre-operative blood sampling and weighing the patient.
- Liaison with the owner to ensure that it is known when to expect a progress report; reassure the owner by all means - but NEVER assume that everything is going to run smoothly; it must be appreciated that every anaesthetic possesses a degree of risk.
List useful equipment to have to hand during a pre-operative assessment.
- Full patient history - particular care must be taken to note pre-existing medical conditions, current medication and any previous adverse drug reactions.
- Scales - an accurate weight is essential in order to work out correct drug dosages.
- Stethoscope - for mediate auscultation (listening to the heart).
- Thermometer - for rectal temperature reading.
- ECG machine - to record the electrical potential of the heart, if required.
- Blood collection equipment - to enable relevant tests, for example blood urea and creatinine levels of a suspected renal case.
Describe briefly what is meant by a high risk case.
A high risk case is a patient exhibiting pathological changes that exacerbate the effects of anaesthetic drugs; hence anaesthesia represents a greater danger than in a normal, healthy animal. Shocked or severely dehydrated animals are most at risk, while elderly patients pose certain degrees of risk due to medical conditions that commonly pre-exist such as renal dysfunction and obesity.
List the details that must be known prior to admission of a patient.
- Owner's name.
- Owner's address and telephone number.
- An emergency contact telephone number if the owner is not at home (a work telephone number and/or mobile number are useful.
- Species, breed, date of birth (this is more accurate than age), sex (including neutering status), colour and markings of the patient.
  Always take extensive details to avoid mistaken identities!
- Vaccination status.
- Insurance status; costs should not be an issue, but unfortunately in this day and age are important (if an estimate has been given, this should also be noted).
- Details of any items left with the animal such as leads, collars, blankets and baskets.
- Patient's weight; details of significant weight loss or gain should also be noted.
- Date and time of anaesthesia and surgery.
- Most importantly - precise details of the anaesthesia and surgery to be performed (anatomical diagrams can be most helpful).
- Current therapy/medication (include any home remedies such as homeopathic medicines which are becoming increasingly popular).
- Previous medical and anaesthetic history; any adverse reactions must be reported.
- Time of last food/water intake.
- Recent medical history as noted at the time of the pre-operative assessment; e.g. heart rate, respiratory rate, body temperature and blood parameters.
It is a legal requirement that a consent form is signed prior to anaesthesia and/or surgery; who may sign this form?
- The owner of the patient providing that he or she is over the age of 18.
- An agent acting upon behalf of the owner; this may be anyone from a friend, relative or neighbour to a solicitor or social worker.
When is the only time that anaesthesia and surgical procedures may be performed without the prior consent of the owner?
Emergency cases where injuries are life-threatening; in such cases, the welfare of the animal is of paramount concern and emergency treatment may be performed without delay. A sadly only too common example are RTA cats brought to the surgery by a members of the general public where owners have not yet been identified.
List the 5 major emergencies that would indicate the need for immediate anaesthesia in order to perform surgery without regard to the condition of the patient.
- Airway obstruction.
- Uncontrollable haemorrhage.
- Cardiac tamponade (impairment of the heart's function by haemorrhage or effusion into the pericardium).
- Severe thoracic injuries.
- Obstetrical emergencies where the neonates are at risk.
What considerations might affect the choice of drugs and dosage for premedication and anaesthesia?
- Temperament, fitness and age of the patient.
- Breed of patient; some breeds respond adversely to certain drugs, for example ACP causes syncope (fainting) in Boxers.
- Anticipated complications.
- Pre-existing conditions and concurrent medication.
- Pain.
- Type and duration of surgical procedure or examination to be undertaken.
- Post-operative requirements; a patient may require immobilisation following a fracture repair and a smooth recovery is essential - Saffan which is commonly used in cats can cause a jerky response during recovery and an alternative induction agent might be preferable.
- Facilities and assistance available.
The general demeanour of a patient offers a beneficial insight as to the risks representative of anaesthesia; explain how depression and excitement affect anaesthesia.
- Depression may be indicative of intracranial pathologies, systemic disease or cardiovascular impairment; depression increases sensitivity to anaesthetics.
- Excitement (including nervousness and aggression) may mean that profound sedation is required.
List visual observations that are helpful in the assessment of a patient prior to anaesthesia and explain their significance.
- Signs of age, such as thickened skin and greying of the coat - elderly patients may have less efficient kidneys thus increasing their anaesthetic risk.
- Sunken eyes and marked skin tenting - these are classic signs of dehydration; a severely dehydrated patient needs correction of electrolyte balance prior to anaesthesia, dehydration is often associated with shock which is contraindicated by anaesthesia.
- Dental disease - severe dental disease may result in toxins circulating in the blood stream which may impair the uptake of oxygen by the blood cells.
- Pale mucous membranes - another indication of shock and/or impaired circulation.
- Respiratory distress - coughing may indicate the presence of airway secretions, while breathless may precede other signs of respiratory and cardiac failure by many months.
- Obesity - this represents a serious risk factor to anaesthesia since it impairs both respiratory and cardiac function.
Palpation is very useful in pre-operative examinations; list areas that are commonly assessed by palpation.
- Dryness of the mucous membranes, particularly the mouth = assessment of hydration status.
- Skin turgor = assessment of hydration status.
- Lymph node enlargement = assessment of the lymphatic system and endocrinology.
- Pulse = assessment of the cardiovascular system.
- Chest movement = assessment of the respiratory system.
- Thrills (tremors detected by palpation) = assessment of the cardiovascular system.
- Position of the cardiac apex beat = the beat of the heart against the chest wall which can be felt during systole.
- Response to pain = assessment of the demeanour of the patient.
Define percussion and auscultation and explain why these techniques are an important part of a pre-operative examination.
- Percussion = a method of diagnosis performed by tapping with the fingers or a light hammer in order to gain information as to the condition of underlying organs; useful in comparison of resonance over the chest wall.
- Auscultation = examination of internal organs by listening to the sounds produced (directly via the ear or mediate via a stethoscope); the heart and respiratory system are commonly assessed in this way. Heart murmers due to valvular defects, patent ductus arteriosus or ventricular septal defects may be detected.
List cardiovascular and respiratory conditions that may be detected by percussion and auscultation.
- Bradycardia = decreased heart rate; may be indicative of heart block (impairment of conduction in heart excitation.
- Tachycardia = increased heart rate; may be indicative of fear, pain, fever or myocardial weakness.
- Diastolic murmers = always indicative of heart disease.
- Venous distension = elevated right atrial or ventricular pressure; may be indicative of chronic lung disease.
- Rales = abnormal respiratory rattling sounds; indicative of fluid in the bronchi.
- Rhonchi = wheezing sounds caused by partial obstruction of the bronchi; may be due to fluid, oedema or spasm.
Why does acquired heart disease represent more of a risk to anaesthesia than congenital heart disease?
Aquired heart disease is more serious since it tends to affect both the myocardium and the heart valves. Examples include pericarditis (inflammation of the serous membrane covering the heart) and cardiomyopathy (dilated - involving thinning of the heart muscle, or hypertrophic - involving thickening of the heart muscle).
In addition to pre-operative haematology and biochemistry blood profiles, what other diagnostic techniques may provide the veterinary surgeon with important information?
- Blood pressure monitoring.
- Central venous pressure measurements
- Radiography.
- Electrocardiography.
- Ultrasound.
- Urine analysis.
Explain why an animal suffering hypoalbuminaemia is a high risk case.
Low volumes of circulating blood albumin is likely to be indicative of liver or renal disease. Drugs such as thio-pentone are "albumin bound" and the lower the albumin levels, the more free thio-pentone is available. This decreases the oncotic pressure of the plasma thus promoting oedema and increasing the diffusion distance for gases in the lungs.
Why are diabetic patients considered high risk anaesthetic cases?
A diabetic patient requires a strict feeding regime which may interfere with the usual starvation requirements prior to anaesthesia. In addition, an unstable diabetic may suffer hyperglycaemia or hypoglycaemia which may be more difficult to detect and treat during anaesthesia.
Pre-operative soluble insulin or intravenous dextrose solutions may be necessary.
Why might anaemia prove to be a problem in an anaesthetised patient?
Low haemoglobin levels may mean that oxygen flux is inadequate once compensatory changes are depressed. Treatment of the underlying cause or a blood transfusion may be necessary.
Why are polycythaemic patients high risk?
Polycythaemia is an abnormal increase in the number of erythrocytes in the blood. This makes the blood hyperviscous and can cause it to sludge in the capillaries thus reducing the efficiency of the cardiovascular system. It may be indicative of dehydration or cardio-pulmonary disease.
Why do pyrexic animals require particular care during anaesthesia?
Pyrexia increases the patient's metabolic rate and therefore oxygen and glucose consumption are raised. Carbon dioxide production is considerably greater and thus it must be ensured that the animal is sufficiently oxygenated and that adequate means for carbon dioxide removal are employed.
Maintenance of anaesthesia by gas inhalation via a mask or closed circuit would not be suitable; a semi-closed circuit reliant upon high fresh gas flow rates would provide the best option since expired carbon dioxide is flushed from the circuit so that it cannot be rebreathed at the next breath.
List 6 drug categories that may produce undesirable side-effects following interaction with anaesthetic drugs.
- Corticosteriods = steroids depress adrenal cortical function and produce signs of atrophy; the adrenal cortex may not be able to secrete sufficient steroid to meet the requirements associated with the stress of anaesthesia and surgery.
- Antibiotics = some antibiotics can contribute to respiratory insufficiency under general anaesthesia.
- Digitalis = Can cause intra-operative arrhythmias; it is recommended that drugs from this group (e.g. Digoxin) are discontinued one to two days prior to anasethesia.
- Endocrine supplements = Insulin and thyoxine are examples of this drug group whose effects upon metabolism may affect general anaesthesia.
- Beta blockers = Drugs such as Propranolol may interact with anaesthetic drugs blocking the pressor responses of hypercapnia.
- Pre-medicant drugs = Some breeds may have a profound response to some drugs, e.g. Boxers to phenothiazine (ACP).
  Other drugs to note are: non-steroidal antiinflammatories, organophosphorous compounds, anticonvulsants, diuretics, ACE inhibitors, antihistamines, antitissusives, bronchodilators and sex hormones.
Why should a patient be starved pre-operatively, and under what circumstances might the usual recommendations be adjusted?
Pre-operative starvation is advisable in order to prevent a full stomach from pressing upon the diaphragm and thus restricting respiratory movement and to prevent vomiting during induction or recovery from anaesthesia. Food is generally withheld 6-8 hrs prior to anaesthesia although some veterinary surgeons recommend a period of up to 12 hours. Water should be available up to 30 minutes prior to surgery. If the animal is polydipsic, polyuric or known to have renal disease; water intake must not be restricted. A diabetic patient must always have food immediately after insulin administration. In addition, very hot weather may necessitate additional water requirements.
If an animal has eaten a large meal pre-operatively, what could be done to reduce the risks associated with anaesthesia and a full stomach?
Vomiting may be induced with morphine, although it is generally considered safer to postpone surgery if possible. The procedure may be delayed until the end of the surgical list or rescheduled for another day. If the owner of the patient has particular difficulty starving their animal; e.g. multi-pet households or known scavengers, it may be wise to hospitalise the patient overnight prior to surgery.
Hypovolaemia and dehydration are serious risk factors to anasethesia; explain their significance.
Hypovolaemia, and indeed all types of shock may result in a sudden fall in blood pressure leading to lack of oxygen in the tissues. This in itself is detrimental during anaesthesia. In addition, the capillary walls possess greater permeability resulting in loss of fluid. Chronic fluid losses may cause electrolyte and pH imbalances further increasing the risks. Ideally, a shocked or dehydrated animal should be stabilised prior to anaesthesia.
Define polydipsia and polyuria and explain their significance in an animal due to be anaesthetised.
Polydipsia (increased thirst), and polyuria (increased micturition) may indicate renal pathology. Water should not be restricted in such cases and parenteral fluids may be required since the patient may be unable to concentrate its urine. Urine specific gravity and blood urea and creatinine levels should be monitored in order to assess the severity of the problem prior to anaesthesia.
Finally, list 10 signs of shock.
- This is a commonly asked question in the oral examination, and is included here due to its significance in anaesthesia.
- Pale, dry mucous membranes
- Slow capillary refill time (normally less than 2 seconds.
- Tachycardia
- Tachypnoea.
- Rapid, feeble pulse.
- Cold extremities
- Depressed demeanour.
- Skin tenting and sunken eyes if dehydration present.
- Shivering.
- Convulsions if the brain becomes hypoxic as a result of severe haemorrhage.

Risk Assessment Of Patient For Anaesthesia

Arlo Guthrie — Tue, 21 Apr 2009 10:13:37 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:13:37

QUESTIONS

What is the purpose of pre-operative assessment?
List useful equipment to have to hand during a pre-operative assessment.
Describe briefly what is meant by a high risk case.
List the details that must be known prior to admission of a patient.
It is a legal requirement that a consent form is signed prior to anaesthesia and/or surgery; who may sign this form?
When is the only time that anaesthesia and surgical procedures may be performed without the prior consent of the owner?
List the 5 major emergencies that would indicate the need for immediate anaesthesia in order to perform surgery without regard to the condition of the patient.
What considerations might affect the choice of drugs and dosage for premedication and anaesthesia?
List visual observations that are helpful in the assessment of a patient prior to anaesthesia and explain their significance.
Palpation is very useful in pre-operative examinations; list areas that are commonly assessed by palpation.
Define percussion and auscultation and explain why these techniques are an important part of a pre-operative examination.
List cardiovascular and respiratory conditions that may be detected by percussion and auscultation.
Why does acquired heart disease represent more of a risk to anaesthesia than congenital heart disease?
In addition to pre-operative haematology and biochemistry blood profiles, what other diagnostic techniques may provide the veterinary surgeon with important information?
Explain why an animal suffering hypoalbuminaemia is a high risk case.
Why are diabetic patients considered high risk anaesthetic cases?
Why might anaemia prove to be a problem in an anaesthetised patient?
Why are polycythaemic patients high risk?
Why do pyrexic animals require particular care during anaesthesia?
List 6 drug categories that may produce undesirable side-effects following interaction with anaesthetic drugs.
Why should a patient be starved pre-operatively, and under what circumstances might the usual recommendations be adjusted?
If an animal has eaten a large meal pre-operatively, what could be done to reduce the risks associated with anaesthesia and a full stomach?
Hypovolaemia and dehydration are serious risk factors to anasethesia; explain their significance.
Define polydipsia and polyuria and explain their significance in an animal due to be anaesthetised.
Finally, list 10 signs of shock.

Physiology Of Anaesthesia & Analgesia - Answers

Arlo Guthrie — Tue, 21 Apr 2009 10:12:05 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:12:05

ANSWERS

Define anaesthesia.
Anaesthesia is defined as the loss of sensation in a part or the whole of the body by controlled, reversible suppression of the central nervous system (CNS). Sensations affected by anaesthesia include appreciation of touch, pressure, temperature and pain. Temperature is of particular consequence since an animal that is unable to regulate its body heat is susceptible to hypothermia; this is why it is very important to keep a patient warm during anaesthesia.
Describe how an animal is able to appreciate pain and how an anaesthetic drug works in order to block this sensation.
Peripheral nerve endings that are sensitive to pain within the sense organs are stimulated causing the sensation of pain. The sensory or afferent nerves deliver the sensation to the spinal cord, and from here it travels to the cerebro-cortical projection areas of the brain. An anaesthetic drug blocks this sensory pathway at any point from the peripheral sense organ affected to the projection areas of the brain thus eliminating the sensation. Remember that sensitivity to touch, pressure and temperature are also affected.
In addition to the depression of sensation, anaesthetics also depress the function of subcortical areas of the brain that receive information regarding unconscious stimuli. List 3 important unconscious stimuli and state the risks relating to them that may result during deep anaesthesia.
- Blood pressure - Hypotension is a risk.
- Blood temperature - Hyothermia is a risk.
- Blood gas levels (oxygen and carbon dioxide) - Hypoventilation is a risk.
List the 3 main needs for anaesthesia.
- Upon humane grounds; to prevent the awareness of pain in an animal undergoing a surgical procedure.
- To facilitate examination of a patient; enabling ease of handling and the provision of skeletal and respiratory muscle relaxation where necessary.
To permit surgery in compliance with the Protection of Animals Act 1964 The aims of anaesthesia may be achieved by the administration of a single agent, however, it is generally safer to use a combination of agents each with a specific action within the body of the patient.
List 2 additional uses of anaesthesia other than those relating to the permission of surgery and subsequent immobilisation and pain relief.
- To aid the control of seizures such as status epilepticus.
- To perform euthanasia (commercial solutions for humane destruction are concentrated anaesthetic drugs).
What are the 2 main ways in which local anaesthetics work?
- The blocking of sensation in the peripheral nerves following a conduction block.
- The blocking of sensation in the spinal cord following an extradural injection.
Drugs affecting the central nervous system are either stimulants or depressants; list and define the types of depressants available.
- General anaesthetics - agents which eliminate sensation by causing unconsciousness.
- Sedatives - agents which calm the patient and cause drowsiness.
- Ataractics/Tranquillisers - drugs which allay anxiety and relieve tension without causing drowsiness.
- Hypnotics/Soporifics - sleep inducing agents from which it is possible to arouse the patient.
- Narcotics - these produce a drug induced stupor characterised by insensibility and paralysis.
  Narcotics may also have stimulant effects on the CNS.
- Neurolepts - agents which relieve emotional distress and produce a state of apathy and mental detachment.
- Neuroleptanalgesics - a combination of agents (a neurolept and an opioid analgesic) which produce deep sedation and analgesia without total loss of consciousness (animals are often hypersensitive to sound).
Most depressants fall into more than one of the categories listed above; what is the main reason for this?
Most agents are dose dependent which means that a low dose is likely to result in quite a different outcome to a high dose.
ACP is both a sedative and tranquilliser.
For what purpose might stimulant drugs be employed in veterinary practice?
Stimulants increase nervous activity and are used to oppose the effects of anaesthetics.
Stimulants are categorised according to site of action; medullary stimulants are most common and are known as analeptics. Doxapram is an example of a stimulant licensed for veterinary use.
An understanding of drug interactions is important in fully comprehending the use of premedicants and anaesthetic agents; define additive, synergy and antagonism.
- Additive - 2 drugs which when taken together have an equal effect to that resulting had they been taken individually (inhalation agents act in an additive way).
- Synergy - 2 drugs which when taken together have a greater effect than if taken separately (neurolepts and opioids act in a synergistic way).
- Antagonism - the effect of the inhibition of one drug by another.
What is the blood-brain barrier, and in what way is it important to the subject of anaesthesia?
The blood-brain barrier (BBB) is a membranous barrier separating the blood from the brain; it is formed by tight junctions between the endothelial cells of the capillaries and the envelopment of the brain capillaries by the glial cells. The BBB is permeable to water, oxygen, carbon dioxide, glucose, alcohol, some drugs and general anaesthetics. In order for anaesthetic agents to cross the BBB quickly, they must be small, non-ionised, lipid soluble and unbound from albumin.
Define analgesia.
Analgesia is defined as insensibility to pain; an analgesic drug reduces the perception of pain without causing loss of consciousness (analgesics interrupt the ascending pain pathway at various levels and suppress the sensation of pain).
The animal's brain is able to respond to pain in 4 main ways; briefly describe each.
- Spinal response - withdrawal reflex.
- Medullary response - increased heart rate, blood pressure and respiratory rate.
- Hypothalamic response - catecholamine release from the adrenal medulla and nerve endings of the sympathetic nervous system causes increased heart rate and blood pressure and piloerection; secretion of releasing factors cause the pituitary gland to release stress hormones.
- Cortical response - voluntary acts such as vocalising and escaping from or biting the stimulus.
List the 6 drug groups that possess the property of analgesia.
- Benzodiazepines.
- General anaesthetics.
- Glucocorticoids.
- Local anaesthetics.
- Non-steroidal anti-inflammatory drugs (NSAIDS).
- Opioids.
In what way do glucocorticoids and non-steroidal anti-inflammatory drugs (NSAIDS) suppress the sensation of pain?
Glucocorticoids and NSAIDS lower nerve ending sensitivity to auticoids (pain sensitising chemicals) from damaged tissue.
In what way do benzodiazepines suppress the sensation of pain?
Benzodiazepines are antagonists with analgesic effects at spinal level.
Define surgical anaesthesia.
Surgical anaesthesia is a state of insensibility enabling the performance of surgery; a combination of unconsciousness, analgesia and muscle relaxation are required.
Define balanced anaesthesia.
Balanced anaesthesia is defined as the use of several drugs in order to achieve unconsciousness, analgesia and muscle relaxation. The use of analgesics and muscle relaxants in addition to general anaesthetic agents means that lower anaesthetic doses may be used, thus preserving vital centre activity.
Why is an understanding of the respiratory system during anaesthesia important?
- Anaesthetics depress ventilation which may contribute to or cause cardiac arrest.
- Volatile anaesthetics are taken up and eliminated by the respiratory system.
  It is essential that the respiratory system is able to provide enough fresh gas to oxygenate the blood and remove carbon dioxide.
Why might flexing the joints of an anaesthetised patient lead to increased depth of respiration or invoke inspiration in an apnoeic animal?
Increased breathing during exercise is due to the influence of sensors in joints and muscles in addition to increased carbon dioxide production.
Carbon dioxide tension in the blood has a powerful effect on respiratory rate which is mediated by a reduction of pH; how is the reduced pH detected?
- Directly by the respiratory centres of the brain (medullary, apneustic and pneumotaxic centres); these are sensitive to the pH of the surrounding cerebro-spinal fluid - carbon dioxide diffuses from the blood to the CSF thus lowering its pH.
- Indirectly by the peripheral chemoreceptors in the carotid and aortic bodies located in the sinuses of the carotid artery and aorta; these respond to falling oxygen tensions in the blood.
Reduced blood oxygen concentration (hypoxia) may lead to respiratory arrest in severe cases; what part of the anatomy monitors the oxygen tension of the blood?
The peripheral chemoreceptors in the carotid and aortic bodies.
Explain the Hering-Bruer reflex.
At peak inspiration, impulses from the receptors within the pleurae and alveolar walls travel to the respiratory centres in the vagus nerve causing inspiration to halt. This prevents over-inflation of the lung parenchyma and subsequent trauma.
Summarise the normal ventilatory cycle.
The normal ventilatory cycle is a continuous unconscious process produced by the rhythmical actions of the respiratory centres. The cycle is adjusted by the influence of feedback from various body areas in order to meet the body's needs.
What is the normal respiratory rate of a cat and dog?
- Cat - 20 to 30 breaths per minute.
- Dog - 10 to 30 breaths per minute (small breeds generally have a higher RR than larger breeds).
Define tidal volume and minute volume, and explain their importance in the subject of anaesthesia.
- Tidal volume is the volume of gas inspired per breath.
- Minute volume is the volume of gas inspired per minute; ie. tidal volume multiplied by respiratory rate.
  In the calculation of flow rates for gaseous anaesthesia it is essential provide enough gas to enable the oxygenation of the blood. Tidal volume may be estimated at 10-15mls/kg (an accurate weight of the patient must be known), and minute volume is calculated by multiplying the tidal volume by the patient's respiratory rate. The minute volume is multiplied by the circuit factor in order to establish the flow rate in l/min. This subject is covered fully later.
What is dead space?
Inspired gas that does not reach the alveoli and therefore is not participant in gaseous exchange. Excessive dead space causes the reduction of alveolar ventilation.
What is anatomic dead space volume?
The portion of inspired gas left at the end of inspiration residing at the level of conducting bronchioles which does not participate in gaseous exchange.
What is mechanical (or apparatus) dead space volume?
Excessive space within anaesthetic equipment at the proximal airway resulting in decreased efficiency of ventilation; an overly long endotracheal tube is an example.
What is alveolar dead space?
Inspired gas that reaches the alveoli but is not perfused with blood and therefore not participant in gaseous exchange.
Anatomic dead space plus alveolar dead space together make up physiologic dead space.
What is the normal measurement of carbon dioxide in arterial blood?
5.33 kPa or 40 mm Hg. The elimination of carbon dioxide is directly proportional to the alveolar volume (volume of inspired gas reaching the alveoli), therefore a normal measurement of blood carbon dioxide is an indicator of adequate ventilation.
Name 2 conditions that may cause hypercapnia/hypercarbia (a build up of carbon dioxide in the blood).
- Pyrexia.
- Malignant hyperthermia.
What is hypoventilation?
Inadequate ventilation resultant from shallow respiration; this may cause hypercapnia/hypercarbia (a build up of carbon dioxide in the blood) and respiratory acidosis. Causes of hypoventilation are:
- Anaesthetic overdose resulting in an insufficient respiratory rate.
- Compression of the chest wall resulting in reduced tidal volume.
- Mechanical dead space resulting in reduced alveolar perfusion.
What is hyperventilation?
Over-ventilation causing hypocapnia/hypocarbia (a deficiency of carbon dioxide in the blood) and respiratory alkalosis. Causes of hyperventilation are:
- Light anaesthesia.
- Pain.
- Excessive manual or mechanical ventilation.
Define respiratory acidosis.
Pulmonary retention of carbon dioxide as a result of impaired ventilation or respiratory arrest.
Define respiratory alkalosis.
Excessive loss of carbon dioxide as a result of hyperventilation.
Hypoxia describes an abnormally low oxygen tension in arterial blood while tissue hypoxia describes active tissues deprived of oxygen as a result of the inadequate oxygenation of haemoglobin; list the possible causes of reduced oxygen delivery to the body tissues:
- Reduced oxygen in inspired gas - perhaps resultant of an empty oxygen cylinder during gaseous anaesthesia.
- Reduced alveolar ventilation - may be caused by excessive dead space, reduced respiratory rate or diminished tidal volume.
- Structural or functional changes of the lungs - neoplasia or pneumonia may severely impair lung function.
- Insufficient haemoglobin available to carry oxygenated blood to the body tissues - anaemic animals are at risk.
- Increased tissue demand - strenuous exercise may cause hypoxia of the myocardium (heart muscle tissue).
Summarise the components of the cardiovascular system and the purpose of cardiovascular activity.
The cardiovascular system comprises:
- Heart.
- Blood vessels.
- Blood.
- The elements of the autonomic nervous system that control the heart's activity.
  The purpose of the cardiovascular system is to transport sufficient volumes of blood containing metabolic reagents through the tissue capillary beds; this is known as perfusion.
What are baroreceptors and where are they located?
Receptors that constantly monitor blood pressure by response to stretch. They are located within the walls of the aortic arch, carotid artery sinus and the large arteries of the neck and thorax.
When blood pressure rises, the artery walls are stretched; the baroreceptors respond resulting in relaxation of the smooth muscle of the blood vessel walls and a subsequent fall in blood pressure to normal levels. When blood pressure falls, the artery walls are less stretched; this results in vasoconstriction causing blood pressure to increase to normal levels.
Anaesthetics depress many facets of cardiovascular function; careful monitoring is therefore essential during anaesthesia. State the normal heart rates for a cat and dog.
- Cat - 110 to 180 bpm.
- Dog - 60 to 180 bpm.
Explain why cardiac output is reduced if the heart rate is very high.
If the heart rate is rapid, there is less time available for the ventricles to fill with blood and therefore a lower stroke volume (the volume of blood ejected per beat); this means that the volume of blood ejected by the heart per minute ie. cardiac output, is lowered.
Define the following terms and explain their significance in the subject of anaesthesia: i) Hypotension. ii) Hypertension. iii) Tachycardia. iv) Bradycardia. v) Oxygen Flux.
- Hypotension = consistently low blood pressure readings as a result of decreased cardiac output and systemic vascular resistance; most anaesthetics depress heart rate and contractility and volatile agents cause vasodilation.
- Hypertension = consistently high blood pressure readings as a result of increased cardiac output and systemic vascular resistance; inadequate anaesthesia causes adrenaline release, and pain on recovery may also contribute.
- Tachycardia = increased heart rate; moderate increases in response to hypotension, hypercapnia and hypoglycaemia are desirable since blood pressure is preserved, however an increase in response to pain may cause the heart to become hypoxic.
- Bradycardia = decreased heart rate; often desirable since ventricular filling and stroke volume are increased while cardiac work is lowered, however, very slow rates may cause hypotension.
- Oxygen flux = the volume of oxygen reaching peripheral tissue per minute I.E cardiac output multiplied by the oxygen content of the blood; anaesthetics reduce oxygen flux and the subsequent lowered percentage saturation of oxygen by haemoglobin may cause lung disease, while direct reduction of haemoglobin may cause severe anaemia.

Physiology Of Anaesthesia & Analgesia

Arlo Guthrie — Tue, 21 Apr 2009 10:10:54 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:10:54

QUESTIONS

Define anaesthesia.
Describe how an animal is able to appreciate pain and how an anaesthetic drug works in order to block this sensation.
In addition to the depression of sensation, anaesthetics also depress the function of subcortical areas of the brain that receive information regarding unconscious stimuli. List 3 important unconscious stimuli and state the risks relating to them that may result during deep anaesthesia.
List the 3 main needs for anaesthesia.
List 2 additional uses of anaesthesia other than those relating to the permission of surgery and subsequent immobilisation and pain relief.
What are the 2 main ways in which local anaesthetics work?
Drugs affecting the central nervous system are either stimulants or depressants; list and define the types of depressants available.
Most depressants fall into more than one of the categories listed above; what is the main reason for this?
For what purpose might stimulant drugs be employed in veterinary practice?
An understanding of drug interactions is important in fully comprehending the use of premedicants and anaesthetic agents; define additive, synergy and antagonism.
What is the blood-brain barrier, and in what way is it important to the subject of anaesthesia?
Define analgesia.
The animal's brain is able to respond to pain in 4 main ways; briefly describe each.
List the 6 drug groups that possess the property of analgesia.
In what way do glucocorticoids and non-steroidal anti-inflammatory drugs (NSAIDS) suppress the sensation of pain?
In what way do benzodiazepines suppress the sensation of pain?
Define surgical anaesthesia.
Define balanced anaesthesia.
Why is an understanding of the respiratory system during anaesthesia important?
Why might flexing the joints of an anaesthetised patient lead to increased depth of respiration or invoke inspiration in an apnoeic animal?
Carbon dioxide tension in the blood has a powerful effect on respiratory rate which is mediated by a reduction of pH; how is the reduced pH detected?
Reduced blood oxygen concentration (hypoxia) may lead to respiratory arrest in severe cases; what part of the anatomy monitors the oxygen tension of the blood?
Explain the Hering-Bruer reflex.
Summarise the normal ventilatory cycle.
What is the normal respiratory rate of a cat and dog?
Define tidal volume and minute volume, and explain their importance in the subject of anaesthesia.
What is dead space?
What is anatomic dead space volume?
What is mechanical (or apparatus) dead space volume?
What is alveolar dead space?
What is the normal measurement of carbon dioxide in arterial blood?
Name 2 conditions that may cause hypercapnia/hypercarbia (a build up of carbon dioxide in the blood).
What is hypoventilation?
What is hyperventilation?
Define respiratory acidosis.
Define respiratory alkalosis.
Hypoxia describes an abnormally low oxygen tension in arterial blood while tissue hypoxia describes active tissues deprived of oxygen as a result of the inadequate oxygenation of haemoglobin; list the possible causes of reduced oxygen delivery to the body tissues.
Summarise the components of the cardiovascular system and the purpose of cardiovascular activity.
What are baroreceptors and where are they located?
Anaesthetics depress many facets of cardiovascular function; careful monitoring is therefore essential during anaesthesia. State the normal heart rates for a cat and dog.
Explain why cardiac output is reduced if the heart rate is very high.
Define the following terms and explain their significance in the subject of anaesthesia: i) Hypotension. ii)Hypertension. iii) Tachycardia. iv) Bradycardia. v)Oxygen Flux.

Anaesthesia & Analgesia

Arlo Guthrie — Tue, 21 Apr 2009 10:09:41 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:09:41

Anaesthesia & Analgesia

Introduction
Anaesthesia is defined as: The loss of sensation in a part or whole of the body by controlled reversible suppression of the central nervous system.

An anaesthetic drug is: A drug that causes anaesthesia.

Analgesia is defined as: Insensibility to pain.

An analgesic drug is: A drug that reduces the perception of pain without causing loss of consciousness.

Anaesthesia and analgesia are often employed to work hand-in-hand in order primarily to ensure that an animal undergoing a surgical procedure does not suffer trauma during and after an operation. The Protection of Animals Act 1964 legally obligates veterinary surgeons to adopt effective techniques to prevent the suffering of a patient during a painful procedure. In addition to humane reasons, anaesthesia is performed to provide immobility or restraint of a patient.

To recap; anaesthesia is necessary:

On humane grounds.
To meet legal requirements.
To provide immobility or restraint.

Times have changed since the days of chloroform, ether and open circuits. The veterinary nurse now plays an essential role in assisting the veterinary surgeon during anaesthesia in the following ways:

Care and maintenance of anaesthetic equipment.
Close and accurate monitoring of a patient prior to, during and following an anaesthetic.
Performance of specific tasks under the direction and supervision of the veterinary surgeon such as intubation, adjustment of vaporiser control, intermittent positive pressure ventilation and administration of drugs.

IMPORTANT NOTE - INDUCTION OF ANAESTHESIA MUST BE PERFORMED BY A VETERINARY SURGEON.

In order to be able to perform the above tasks safely and accurately, thorough training is necessary in all aspects of anaesthesia. Reading alone is never enough to fully understand the techniques involved; practical lectures and demonstrations are essential. An animal's life may be in your hands, therefore the most vital piece of information is: ALWAYS ASK IF YOU ARE UNSURE REGARDING ANY ASPECT OF ANAESTHESIA.

Learning Objectives

To understand the effect of anaesthesia and analgesia on the central nervous system, respiratory system and cardiovascular system.
To perform risk assessment of a patient prior to anaesthesia.
To understand why premedicant drugs are used.
To understand why analgesic drugs are used.
To comprehend the different types of anaesthesia available and know when their uses would be suitable.
To safely use anaesthetic equipment; including circuits, accessories and the general anaesthetic machine.
To accurately monitor the periods and planes of general anaesthesia.
To recognise an anaesthetic crisis and be able to act in an emergency.
To gain knowledge regarding the anaesthesia of exotic species.
To perform risk assessment of personnel involved in anaesthesia.

Remember, this book is intended as a revision guide, and further reading is recommended. Helpful references are included at the end of this chapter.

Anaesthesia & Analgesia

Arlo Guthrie — Tue, 21 Apr 2009 10:08:58 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:08:58

Introduction
Anaesthesia is defined as: The loss of sensation in a part or whole of the body by controlled reversible suppression of the central nervous system.

An anaesthetic drug is: A drug that causes anaesthesia.

Analgesia is defined as: Insensibility to pain.

An analgesic drug is: A drug that reduces the perception of pain without causing loss of consciousness.

To recap; anaesthesia is necessary:

On humane grounds.
To meet legal requirements.
To provide immobility or restraint.

Care and maintenance of anaesthetic equipment.
Close and accurate monitoring of a patient prior to, during and following an anaesthetic.
Performance of specific tasks under the direction and supervision of the veterinary surgeon such as intubation, adjustment of vaporiser control, intermittent positive pressure ventilation and administration of drugs.

IMPORTANT NOTE - INDUCTION OF ANAESTHESIA MUST BE PERFORMED BY A VETERINARY SURGEON.

Summary & Further Reading

Arlo Guthrie — Tue, 21 Apr 2009 10:07:30 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 11:07:30

This is a chapter in which many of the topics overlap other subjects in the syllabus. I have endeavoured to elaborate on those that have only been touched on briefly, whilst providing references to enable you to source information on those that have already been covered in depth.

Practical experience is an absolute must. It is very unusual to sit a practical exam without having to dress at least one part of an animal, so do make sure that your bandaging technique is spot on!

Dislocations - Answers

Arlo Guthrie — Tue, 21 Apr 2009 09:34:08 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:34:08

ANSWERS

What is another term for a dislocation?
Luxation.
What is another term for a partial dislocation?
Subluxation.
Define dislocation.
A persistent and complete displacement of the opposing articular surfaces of the bones forming a joint.
Define subluxation.
An incomplete displacement of the opposing articular surfaces of the bones forming a joint.
Give an example of a common congenital luxation.
Luxating patella.
Name the 2 joints that are most commonly affected by acquired luxation occurring as a result of trauma.
- Hip.
- Elbow.
What is the correct term for reduction of the joint by manipulation of the affected limb?
Closed reduction.
Describe open reduction.
A surgical approach to the joint involving visualisation of the affected bones and their subsequent manipulation back into the joint.
Why is closed reduction preferable to open reduction?
- Less risk of joint infection.
- No surgical wound to look after.
Why is it very unlikely that the veterinary surgeon will be able to perform successful closed reduction on a 3 day old luxation?
During this time the surrounding tissues will have contracted, thus rendering closed reduction difficult.
What should always be carried out before any attempt is made at reduction and why?
Radiography; it is important to confirm the diagnosis, aswell as assess any further damage such as fractures (which will complicate any attempts to reduce the affected joint).
How long should an animal be rested for following the reduction of a luxation?
3-4 Weeks.
What is the name of the dressing that may be used to support a hind limb following reduction of a luxated hip?
Ehmer sling.
What is the name of the dressing that may be used to support a forelimb following reduction of a luxated elbow?
Velpeau sling.
For how long are non-weight-bearing slings usually employed following the reduction of a luxation?
5-7 Days.
State 4 complications associated with luxations.
- Reluxation after reduction.
- Joint infection (following open reduction).
- Injury to the soft tissues surrounding the affected joint.
- Nerve damage in the region of the affected joint.

Dislocations

Arlo Guthrie — Tue, 21 Apr 2009 09:32:22 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:32:22

QUESTIONS

What is another term for a dislocation?
What is another term for a partial dislocation?
Define dislocation.
Define subluxation.
Give an example of a common congenital luxation.
Name the 2 joints that are most commonly affected by acquired luxation occurring as a result of trauma.
What is the correct term for reduction of the joint by manipulation of the affected limb?
Describe open reduction.
Why is closed reduction preferable to open reduction?
Why is it very unlikely that the veterinary surgeon will be able to perform successful closed reduction on a 3 day old luxation?
What should always be carried out before any attempt is made at reduction and why?
How long should an animal be rested for following the reduction of a luxation?
What is the name of the dressing that may be used to support a hind limb following reduction of a luxated hip?
What is the name of the dressing that may be used to support a forelimb following reduction of a luxated elbow?
For how long are non-weight-bearing slings usually employed following the reduction of a luxation?
State 4 complications associated with luxations.

Internal Fracture Repair - Answers

Arlo Guthrie — Tue, 21 Apr 2009 09:14:07 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:14:07

Internal Fracture Repair - Answers

ANSWERS

List 3 advantages of internal fixation.
- Accurate.
- Versatile.
- Early return to full functional limb use.
List 3 disadvantages of internal fixation.
- Time consuming and technically demanding.
- Expensive.
- Risk of infection.
What is the name of the intramedullary pin that is the most commonly used internal fixation device in small animal orthopaedic surgery?
Steinman pin.
What is the main difference between Kirschner wires and arthrodesis wires?
Kirschner wires have a flattened point, whilst arthrodesis wires possess a trocar point.
What is the name of the highly specialised curved pin that is used to anchor small epiphyseal fragments back onto the shaft of a bone?
Rush pin.
What is the main function of cerclage wire?
It is often used in combination with pins and plates to improve fracture stability.
State the 2 most common types of bone plate that are held in place by self-tapping screws.
- Sherman plate.
- Venables plate.
State 3 advantages of the use of dynamic compression plates.
- Better resistance.
- Better contact.
- Use tapped screws that can easily be removed and replaced without causing undue weakening to the bone.
How can ASIF screws be easily identified?
They are blunt and have a hexagonal pattern.

Further information regarding orthopaedic instruments can be found in Part II - Chapter 8 - Theatre Practice.

Internal Fracture Repair - Answers

Arlo Guthrie — Tue, 21 Apr 2009 09:13:46 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:13:46

ANSWERS

List 3 advantages of internal fixation.
- Accurate.
- Versatile.
- Early return to full functional limb use.
List 3 disadvantages of internal fixation.
- Time consuming and technically demanding.
- Expensive.
- Risk of infection.
What is the name of the intramedullary pin that is the most commonly used internal fixation device in small animal orthopaedic surgery?
Steinman pin.
What is the main difference between Kirschner wires and arthrodesis wires?
Kirschner wires have a flattened point, whilst arthrodesis wires possess a trocar point.
What is the name of the highly specialised curved pin that is used to anchor small epiphyseal fragments back onto the shaft of a bone?
Rush pin.
What is the main function of cerclage wire?
It is often used in combination with pins and plates to improve fracture stability.
State the 2 most common types of bone plate that are held in place by self-tapping screws.
- Sherman plate.
- Venables plate.
State 3 advantages of the use of dynamic compression plates.
- Better resistance.
- Better contact.
- Use tapped screws that can easily be removed and replaced without causing undue weakening to the bone.
How can ASIF screws be easily identified?
They are blunt and have a hexagonal pattern.

Further information regarding orthopaedic instruments can be found in Part II - Chapter 8 - Theatre Practice.

Internal Fracture Repair

Arlo Guthrie — Tue, 21 Apr 2009 09:13:14 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:13:14

QUESTIONS

List 3 advantages of internal fixation.
List 3 disadvantages of internal fixation.
What is the name of the intramedullary pin that is the most commonly used internal fixation device in small animal orthopaedic surgery?
What is the main difference between Kirschner wires and arthrodesis wires?
What is the name of the highly specialised curved pin that is used to anchor small epiphyseal fragments back onto the shaft of a bone?
What is the main function of cerclage wire?
State the 2 most common types of bone plate that are held in place by self-tapping screws.
State 3 advantages of the use of dynamic compression plates.
How can ASIF screws be easily identified?

Further information regarding orthopaedic instruments can be found in Part II - Chapter 8 - Theatre Practice.

Fractures - Answers

Arlo Guthrie — Tue, 21 Apr 2009 09:06:09 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:06:09

ANSWERS

What is the term that describes a fracture resulting from the normal use of a bone weakened by a disease process?
A pathological fracture.
List 8 signs or symptoms that may be displayed by an animal suffering a fractured limb bone.
- Inflammation/swelling.
- Heat.
- Pain (and associated signs such as vocalisation, depression and/or aggression).
- Contusions.
- Lameness/abnormal mobility/guarding of the affected limb.
- Loss of function.
- Visible or palpable deformity of the affected limb.
- Crepitus.
Briefly describe the principles of fracture first aid.
- Ensure adequate restraint.
- Prioritise treatment remember the first aid A-B-C.
- Treat shock - administer fluid therapy and ensure that the animal is kept warm.
- Cover any open wounds with clean, sterile dressings.
- Immobilise the fracture before attempting to move the animal.
- Control haemorrhage.
- Perform a full clinical examination.
- Administer drugs in accordance with the directions of the veterinary surgeon.
State the 3 main indications for fracture fixation.
- Pain relief.
- Prevention of displacement of the bone fragments in order to provide accurate anatomical reduction.
- Prevention of movement that may delay healing or cause non-union.
What is the name of the large support dressing often used to immobilise a fractured limb in a first aid situation?
Robert Jones dressing.
What should always be performed in cases of a suspected fracture?
Radiography; in order to confirm the diagnosis.
What is the name given to a fracture affecting the mid-shaft of a bone?
Diaphyseal fracture.
What is a physeal fracture?
A fracture through the growth plate of an immature animal.
By what name is a physeal fracture also known?
Salter Harris fracture.
What part of the body is most likely to be affected by a depressed fracture?
The skull.
What is a greenstick fracture?
An incomplete fracture where the bone is fissured, but the fragments are not completely separated by the fracture line. This type of fracture is most common in immature animals.
What is the difference between a compound and a complicated fracture?
A compound fracture is one in which there is a wound communicating between the skin or mucous membranes and the fracture site, whilst a complicated fracture is one in which important structures or organs around the fracture site are damaged.
What is the name given to a complex fracture creating 3 or more bone fragments?
A comminuted fracture?
Give 3 examples of terms used to describe the direction of a fracture line relative to the bone.
- Oblique.
- Spiral.
- Transverse.
List the 4 main processes involved in fracture healing.
- Haematoma formation (within 6-8 hrs).
- Granulation (invasion of stem cells).
- Callous formation (of fibrous tissue).
- Remodelling (replacement of the callous with new bone).
How long does it take for a fracture to heal in a normal adult animal?
12-16 Weeks (although remodelling may persist for years).
List 6 factors that may cause delayed healing of a fracture.
- The animal is geriatric.
- The animal was debilitated and in poor general health prior to the accident.
- The fracture is of cortical rather than cancellous bone.
- The fractured bone has a poor blood supply.
- The fracture is transverse rather than oblique.
- The fracture has been poorly reduced or repaired (mal-union).
What is the term that describes a fracture that is healing more slowly than originally anticipated?
Delayed union.
What complication is associated with poor aseptic technique and/or where the local blood supply to a fracture site is damaged?
Osteomyelitis.
List 5 factors that may influence the reason for choosing a particular method of fracture repair.
- Type of fracture.
- Cost.
- Species/breed.
- Skill of the veterinary surgeon.
- Availability of equipment.
What are the 2 main types of external coaption?
- Casting.
- Splinting.
Why can splints only be used to immobilise joints below the elbow and stifle?
The large muscle masses that surround the joints above these mean that immobilisation is impossible.
List 6 types of splint.
- Use of the body itself (eg. the binding of the scapula to the rib cage).
- Wood.
- Metal with foam padding (eg. Zimmer splint).
- Plastic (eg. gutter splint).
- Wood.
- Plaster slabs or resin.
Give an example of a type of extension splint.
Schroeder-Thomas traction device.
When might the use of an extension splint be indicated?
- To immobilise a fracture distal to the middle of the femur in the hindlimb.
- To immobilise a fracture distal to the middle of the humerus in the forelimb.
- To immobilise a joint at or below the level of the stifle in the hindlimb.
- To immobilise a joint at or below the level of the elbow in the forelimb.
State 2 advantages of a split cast.
- Enables frequent inspection of the limb with minimal hassle.
- Has a little "give" and is therefore useful in growing animals.
The use of casts to immobilise fractures is much reduced as a result of improved techniques in internal fixation. It can however play a useful role in certain types of fracture. What types of fractures are suitable for casting?
Easily reducible, stable fractures that are distal to the elbow and stifle.
Greenstick fractures.
List 5 disadvantages of Plaster of Paris.
- Takes a long time to dry and achieve maximum strength.
- Heavy.
- Affected by water and wear and tear.
- Relatively radiodense.
- Messy to apply, and quite difficult to remove.
Give 2 examples of casting materials that are generally considered to be preferable to plaster of Paris.
- Thermomoldable plastics (eg. Hexcelite).
- Cold water setting fibre glass materials (eg. Vetcast).
State 8 advantages of cold water setting fibre glass materials.
- Light.
- Conforming.
- Rapid drying.
- Water-proof.
- Reasonably radiolucent.
- Stands up well to wear and tear.
- Non-invasive.
- Easy to apply.
State the basic principles that must be adhered to when casting to ensure maximum success with this technique.
- General anaesthesia should be used to aid reduction.
- The joint above and below the fracture must be immobilised.
- Cast padding should be snug enough to prevent chafing, but not excessive since this may cause the cast to loosen and rub.
- If it is decided that the toes are to be left exposed when casting a limb, ensure that not too much of the foot is exposed otherwise swelling is almost inevitable.
- The cast should be changed at 2 weeks following reduction since soft tissue swelling will have subsided with the subsequent loosening of the cast.
- Growing animals require more frequent cast changes than adults.
- Ensure that the owner is given full instructions regarding cast care.
List 10 factors regarding cast care that an owner should be made aware of.
- The cast should be checked daily.
- Exercise must be restricted (lead exercise only for dogs; cage rest only for cats).
- Any problems should be reported immediately.
- Patient interference must be prevented.
- The cast must be kept clean and dry.
- Be watchful for swelling or coldness of the toes in a limb cast where the digits are left exposed.
- Report any incidence of odour emanating from the cast.
- Report any incidence of damage to the cast.
- Ensure that the cast is not rubbing.
- The cast should be inspected by a veterinary surgeon at least once a week.
What is external skeletal fixation?
A means of stabilising long bone fractures using percutaneously placed fixation pins that are connected externally to form a rigid frame.
How can pin tract infections be reduced during external skeletal fixation.
- Good aseptic technique.
- Avoidance of pin insertion through large muscle masses.
- Insertion of the pins via small stab incisions rather than through intact skin or open wounds.
Why should the use of high pressure, high speed power equipment be avoided when inserting fixation pins?
The heat generated by such equipment may cause heat necrosis, which will cause premature pin loosening.
During external skeletal fixation, why is it important that the fixation pins are placed at 35-40° angles to one another?
- To lessen the chance of accidental dislodgement of the device.
- To minimise side-to-side sliding of the device as it loosens with time.
State the name of an external skeletal fixation device commonly used in small animal practice.
Kirschner splint.
List 6 indications for the use of external skeletal fixation.
- Comminuted fractures - can stabilise fractures relatively quickly with little risk to damaging the blood supply to small bone fragments.
- Open or infected fractures - pins can be placed well away from an infected area; especially useful for gun shot wounds.
- Fractures of the skull and jaw.
- Fractures of long bones in immature animals - pins can be placed to avoid passing through growth plates.
- Immobilisation of joints - can maintain a joint in the correct anatomical position until complete fusion has occurred.
- Combinations of internal and external fixation - may be combined with an intramedullary pin in order to prevent rotation at a fracture site.

Fractures

Arlo Guthrie — Tue, 21 Apr 2009 09:05:15 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:05:15

QUESTIONS

What is the term that describes a fracture resulting from the normal use of a bone weakened by a disease process?
List 8 signs or symptoms that may be displayed by an animal suffering a fractured limb bone.
Briefly describe the principles of fracture first aid.
State the 3 main indications for fracture fixation.
What is the name of the large support dressing often used to immobilise a fractured limb in a first aid situation?
What should always be performed in cases of a suspected fracture?
What is the name given to a fracture affecting the mid-shaft of a bone?
What is a physeal fracture?
By what name is a physeal fracture also known?
What part of the body is most likely to be affected by a depressed fracture?
What is a greenstick fracture?
What is the difference between a compound and a complicated fracture?
What is the name given to a complex fracture creating 3 or more bone fragments?
Give 3 examples of terms used to describe the direction of a fracture line relative to the bone.
List the 4 main processes involved in fracture healing.
How long does it take for a fracture to heal in a normal adult animal?
List 6 factors that may cause delayed healing of a fracture.
What is the term that describes a fracture that is healing more slowly than originally anticipated?
What complication is associated with poor aseptic technique and/or where the local blood supply to a fracture site is damaged?
List 5 factors that may influence the reason for choosing a particular method of fracture repair.
What are the 2 main types of external coaption?
Why can splints only be used to immobilise joints below the elbow and stifle?
List 6 types of splint.
Give an example of a type of extension splint.
When might the use of an extension splint be indicated?
State 2 advantages of a split cast.
The use of casts to immobilise fractures is much reduced as a result of improved techniques in internal fixation. It can however play a useful role in certain types of fracture. What types of fractures are suitable for casting?
List 5 disadvantages of Plaster of Paris.
Give 2 examples of casting materials that are generally considered to be preferable to plaster of Paris.
State 8 advantages of cold water setting fibre glass materials.
State the basic principles that must be adhered to when casting to ensure maximum success with this technique.
List 10 factors regarding cast care that an owner should be made aware of.
What is external skeletal fixation?
How can pin tract infections be reduced during external skeletal fixation.
Why should the use of high pressure, high speed power equipment be avoided when inserting fixation pins?
During external skeletal fixation, why is it important that the fixation pins are placed at 35-40° angles to one another?
State the name of an external skeletal fixation device commonly used in small animal practice.
List 6 indications for the use of external skeletal fixation.

I/V Admin Of Chemotherapy Drug - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 09:04:24 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:04:24

I/V Admin Of Chemotherapy Drug - Practical Task

INTRODUCTION
The administration of cytotoxic drugs must be approached with great caution due to risks posed to personnel. Further information regarding cytotoxic drugs can be found in Part I - Pharmacy & Dispensing.

SAMPLE QUESTION
Prepare the equipment necessary for the intravenous administration of Vincristine to a cat suffering from lymphoma.

Equipment

Protective clothing: disposable plastic suit with long sleeves, face mask, goggles and gloves (protective clothing must ALWAYS be used when preparing or administering chemotherapeutic drugs).
Electric clippers or curved scissors.
Skin disinfectant.
Industrial methylated spirit.
Suitably sized intravenous catheter - 23g or 25g are suitable depending upon the preference of the veterinary surgeon.
It is wise to choose zinc oxide tape over some of less adhesive rivals since it is absolutely essential that the catheter does not move from the vein once in place. Elastoplast may cause skin reaction in some dogs.
Rubber bung.
Sterile water.
2ml Syringe and 21g needle.
1ml Syringe and 23g needle.
Vincristine injection contained within a special container labelled "Cytotoxic Drugs".
Cytotoxic dispensing box (this is usually a plastic container filled with plenty of absorbent material over which the drug is drawn up for extra safety).
DOOP cytotoxic disposal container (yellow with pink writing).
Spillage kit (you shouldn't be needing this, but it is vital that the cytotoxic drug prep and admin area has one to hand).

Method

Ensure that the area in which you are about to work is clearly designated as an area for the preparation and administration of cytotoxic drugs.
Adorn protective plastic suit, gloves, goggles and face mask.
Draw up the correct amount of Vincristine, working carefully over the cytotoxic dispensing box. (1ml insulin syringes are ideal as they are extremely accurate - but remember that Caninsulin syringes are unsuitable since they have their own unit scale). Ensure that the Vincristine is returned to its special container and replaced within the refrigerator after use. Ensure that the needle attached to the syringe containing the drug is covered. The Vincristine syringe must then be labelled and placed in the dispensing box ready for use.
Draw up 2mls of sterile water - this is used to establish that the intravenous catheter is patent within the vein before and after the administration of the Vincristine. Label the syringe and ensure that the needle attached to the syringe is covered.
Lay out the equipment used to place an i/v catheter; ie. clippers, scissors, skin disinfectant, swabs, industrial methylated spirit, 23g or 25g catheter, strips of tape to secure the catheter once in the vein and a rubber bung.

I/V Admin Of Chemotherapy Drug - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 09:02:30 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:02:30

SAMPLE QUESTION
Prepare the equipment necessary for the intravenous administration of Vincristine to a cat suffering from lymphoma.

Equipment

- Protective clothing: disposable plastic suit with long sleeves, face mask, goggles and gloves (protective clothing must ALWAYS be used when preparing or administering chemotherapeutic drugs).
- Electric clippers or curved scissors.
- Skin disinfectant.
- Industrial methylated spirit.
- Suitably sized intravenous catheter - 23g or 25g are suitable depending upon the preference of the veterinary surgeon.
  It is wise to choose zinc oxide tape over some of less adhesive rivals since it is absolutely essential that the catheter does not move from the vein once in place. Elastoplast may cause skin reaction in some dogs.
- Rubber bung.
- Sterile water.
- 2ml Syringe and 21g needle.
- 1ml Syringe and 23g needle.
- Vincristine injection contained within a special container labelled "Cytotoxic Drugs".
- Cytotoxic dispensing box (this is usually a plastic container filled with plenty of absorbent material over which the drug is drawn up for extra safety).
- DOOP cytotoxic disposal container (yellow with pink writing).
- Spillage kit (you shouldn't be needing this, but it is vital that the cytotoxic drug prep and admin area has one to hand).

Method

1. Ensure that the area in which you are about to work is clearly designated as an area for the preparation and administration of cytotoxic drugs.
2. Adorn protective plastic suit, gloves, goggles and face mask.
3. Draw up the correct amount of Vincristine, working carefully over the cytotoxic dispensing box. (1ml insulin syringes are ideal as they are extremely accurate - but remember that Caninsulin syringes are unsuitable since they have their own unit scale). Ensure that the Vincristine is returned to its special container and replaced within the refrigerator after use. Ensure that the needle attached to the syringe containing the drug is covered. The Vincristine syringe must then be labelled and placed in the dispensing box ready for use.
4. Draw up 2mls of sterile water - this is used to establish that the intravenous catheter is patent within the vein before and after the administration of the Vincristine. Label the syringe and ensure that the needle attached to the syringe is covered.
5. Lay out the equipment used to place an i/v catheter; ie. clippers, scissors, skin disinfectant, swabs, industrial methylated spirit, 23g or 25g catheter, strips of tape to secure the catheter once in the vein and a rubber bung.

Tumours - Answers

Arlo Guthrie — Tue, 21 Apr 2009 09:01:06 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:01:06

ANSWERS

What is a tumour?
An abnormal swelling of tissue that has no physiological use, and in which cell growth and mitosis is uncoordinated and exceeds that of the normal tissue cells.
What is the term used to describe a cancerous tumour?
Neoplastic.
What is the term used to describe a non-cancerous tumour?
Benign.
State 4 characteristics of benign tumours.
- Usually slow growing (but not always).
- Often discrete and encapsulated.
- Often moveable relative to neighbouring tissues.
- Do not metastasise to other organs.
State 4 characteristics of malignant tumours.
- Often fast growing.
- Often aggressive and irregular.
- Locally invasive and not freely mobile.
- May metastasise to other organs.
What is the name given to a benign tumour of adipose (fat) cells?
Lipoma.
What are epulides?
Benign tumours found primarily on the gum.
What is another name for a wart?
Papilloma.
What skin tumour may be either malignant or benign?
Melanoma.
A dog is brought to the surgery with a tumour that the veterinary surgeon suspects is a fibroma. Why is it sensible to biopsy such a mass?
Fibromas are benign tumours of the skin, but it is often difficult to differentiate them from other malignant types of tumour.
What is the fixative of choice for most routine histopathology?
10% Formol saline (see Part I - Anatomy & Physiology: Cells, Tissues & Organs).
An adenoma is a benign tumour of glandular tissue often affecting older dogs. Where is the most common site for such tumours?
The anus.
Why should a dog be castrated at the same time as undergoing surgery to
remove an anal adenoma?
The growth of an anal adenoma is dependent upon the male sex hormones.
What is the most common site for metastases via the circulation?
The lungs.
What is the difference between a carcinoma and a sarcoma?
A carcinoma is a malignant tumour arising from the epithelial cells, whilst a sarcoma is a malignant tumour arising from the mesenchymal (mainly connective) tissues.
In what part of the body are squamous cell carcinomas most commonly found?
The oral cavity.
In what part of the body are transitional cell carcinomas most commonly found?
The urinary tract.
What is an adenocarcinoma?
A malignant tumour of the glandular tissue.
Lymphosarcoma in cats is commonly associated with which disease?
Feline leukaemia virus (FeLV).
What is an osteosarcoma?
A malignant tumour of the osteoblasts.
Are mixed mammary tumours malignant or benign?
Benign.
In bitches, which mammary glands are the most frequently affected by tumours?
The 2 most caudal pairs.
What is the name of the procedure that involves the radical removal of a tumour along with a section of the mandible?
Mandibulectomy.
What is the name of the procedure that involves the radical removal of a tumour along with a section of the maxilla?
Maxillectomy.
What is the name that describes the non-invasive technique involving the sampling of cells of a tumour by use of a needle and suction device?
Fine needle aspiration.
For what purpose is a Tru Cut needle employed?
Performing a needle core biopsy; it consists of a central obturator which is notched, an outer sleeve or cannula and a handle. The obturator is inserted into the tumour tissue and the cannula advanced over the obturator in order to trap a small cylinder of tissue.
What is a punch biopsy?
The collection of a small, circular area of superficial tissue by means of a specially designed tool that employs a sharp, circular blade.
What type of tissue is collected by means of a trephine biopsy?
Bone.
What is the difference between an incisional and excisional biopsy?
An incisional biopsy involves the removal of a small wedge of tissue, whilst an excisional biopsy involves the removal of all identifiable tumour tissue.
What is debulking?
The removal of as much tumour tissue as possible in circumstances whereby complete excision is impractical.
What is the term that describes the use of drugs to kill tumour cells selectively?
Chemotherapy (see Part I - Pharmacy & Dispensing for a section on cytotoxic drugs).
What is radiotherapy?
The use of radiation to selectively kill tumour cells.
What is the term that describes the use of more than one method of treatment used on a single tumour?
Combined/multi modality.
What is adjunctive therapy?
Therapy used in the care of the cancer patient in addition to the direct treatment of the tumour itself. This may include the administration of analgesia and antibiotics, wound management and the provision of prescription diets.

Tumours

Arlo Guthrie — Tue, 21 Apr 2009 09:00:24 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 10:00:24

QUESTIONS

What is a tumour?
What is the term used to describe a cancerous tumour?
What is the term used to describe a non-cancerous tumour?
State 4 characteristics of benign tumours.
State 4 characteristics of malignant tumours.
What is the name given to a benign tumour of adipose (fat) cells?
What are epulides?
What is another name for a wart?
What skin tumour may be either malignant or benign?
A dog is brought to the surgery with a tumour that the veterinary surgeon suspects is a fibroma. Why is it sensible to biopsy such a mass?
What is the fixative of choice for most routine histopathology?
An adenoma is a benign tumour of glandular tissue often affecting older dogs. Where is the most common site for such tumours?
Why should a dog be castrated at the same time as undergoing surgery to
remove an anal adenoma?
What is the most common site for metastases via the circulation?
What is the difference between a carcinoma and a sarcoma?
In what part of the body are squamous cell carcinomas most commonly found?
In what part of the body are transitional cell carcinomas most commonly found?
What is an adenocarcinoma?
Lymphosarcoma in cats is commonly associated with which disease?
What is an osteosarcoma?
Are mixed mammary tumours malignant or benign?
In bitches, which mammary glands are the most frequently affected by tumours?
What is the name of the procedure that involves the radical removal of a tumour along with a section of the mandible?
What is the name of the procedure that involves the radical removal of a tumour along with a section of the maxilla?
What is the name that describes the non-invasive technique involving the sampling of cells of a tumour by use of a needle and suction device?
For what purpose is a Tru Cut needle employed?
What is a punch biopsy?
What type of tissue is collected by means of a trephine biopsy?
What is the difference between an incisional and excisional biopsy?
What is debulking?
What is the term that describes the use of drugs to kill tumour cells selectively?
What is radiotherapy?
What is the term that describes the use of more than one method of treatment used on a single tumour?
What is adjunctive therapy?

Veterinary Dentistry - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:59:22 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:59:22

ANSWERS

What is the difference between plaque and tartar?
Plaque is a film-like deposit on the surface of the tooth consisting of salivary deposits, food particles and gram positive bacteria, whilst tartar is a stonelike concretion of minerals. Plaque can be removed by brushing, but tartar requires removal with dental forceps or an ultrasonic scaler.
What is another name for tartar?
Dental calculus.
List 10 signs that may be present in an animal suffering from dental disease.
- Gingivitis.
- Stomatitis.
- Oral ulceration.
- Build up of tartar.
- Halitosis.
- Rubbing the face/mouth along carpets/furniture.
- Dysphagia.
- Fear of food/anorexia.
- Weight loss.
- Excessive salivation
What is the irreversible stage of periodontal disease called?
Periodontitis.
State 4 complications associated with dental extractions.
- Retained tooth root.
- Persistent haemorrhage.
- Iatrogenic fracture of the mandible or maxilla.
- Creation of oronasal fistulae.
At what age are the deciduous teeth lost in cats and dogs?
4-5 Months.
At what age is permanent dentition complete in cats and dogs?
7 Months.
How many teeth do adult cats and dogs possess?
- Cats - 30.
- Dogs - 42.
How many teeth do puppies and kittens possess?
- Puppies - 28.
- Kittens - 26.
What teeth are present in cats and dogs, but not in rabbits?
- Canines.
- Carnassials.
How many roots are possessed by the carnassials?
3.
Why should dental scaling never be performed at the same time as other surgery?
Scaling releases copious amounts of bacteria from the oral cavity that may enter the blood stream and cause infection of surgical wounds.
For how long should the tip of the ultrasonic scaler be in continuous contact with the tooth?
No more than 15 seconds.
For what purpose is prophy polish employed?
To produce a smooth surface on the tooth following ultrasonic scaling.
What is malocclusion?
Poor apposition of the teeth.
What is another name for normal occlusion?
Scissor bite.
What is prognathism?
A term describing an animal with the mandible too long for the maxilla so that the chin appears to be thrust forward; also known as "undershot".
State 2 breeds of dog affected by prognathism.
- British bulldog.
- Boxer.
What is brachygnathism?
A term describing an animal with the mandible too short for the maxilla so that the chin appears to recede; also known as a "parrot mouth" or "overshot".
State 2 breeds of dog in which brachygnathism is often seen.
- Toy poodles.
- Yorkshire terriers.
What is wry bite?
This occurs when one side of the head grows longer than the other; if the right mandible grows longer than the left then the 3 right lower incisors come to lie cranial to the 3 right upper incisors, while both sets of left hand incisors lie as they would normally.
What is the term used to describe the occurrence of some of the upper incisors resting caudal to the lower incisors?
Anterior crossbite.
What instruments might you use to loosen a tooth prior to extraction?
- Elevator.
- Number 11 scalpel blade.
What instrument would you choose to extract a retained deciduous tooth?
A luxator.
Describe probe evaluation of periodontal disease.
A periodontal probe (with millimetre markings) is inserted into the interproximal space sulcus in order to gauge the degree of bone loss. Normally, the probe should extend 2mm below the gum line.
What is a gingivectomy?
The surgical removal of overgrown gum tissue; the treatment of gingival hyperplasia.
Why is the mouth a major source of disease affecting the heart, liver and kidneys?
Pathogenic organisms are able to enter the blood stream via the mouth and travel to other parts of the body.
What is the correct name for a tooth socket?
Alveolus.
What is the correct name for the alveolar lining?
The lamina dura.
What is the pellicle?
The acellular glycoprotein layer that covers the enamel of the tooth.
What is the zone where the crown and the root of the tooth meet?
The cemento-enamel-junction (CEJ).
What substances make up the periodontal ligament?
- Collagen.
- Elastic fibres.
List ways in which the safety and comfort of both operator and patient can be ensured during dental prophylaxis?
- The operator should adorn protective apron, gloves, mask and goggles.
- The patient should be anaesthetised with an endotracheal tube in place and the cuff inflated.
- The patient's head should be rested on a foam wedge keeping the rostral head downmost enabling good drainage of debris and water out of the mouth, ideally through a grid and into a collecting tray.
- Assistance must be enlisted when turning a large patient. The animal should never be turned over dorsally since debris may be ingested.
- A gag of an appropriate size should be used to keep the patient's mouth open.
- The pharynx should be packed with loose weave surgical swabs in order to prevent accumulation of debris that may later become respiratory foreign bodies. These must be carefully counted and removed following the procedure.
- The designated area for dental procedures should be well ventilated and ideally possess an air conditioning or air filtering system in order to reduce aerosol spread of debris and pathogens.
- A well designed, supportive chair, of adjustable height will minimise neck and back strain.
- Good lighting will facilitate efficient oral examination.
List ways in which you can encourage owners to ensure a good level of home dental care.
- Recommend that dental care should begin when the pet is as young as 12 weeks old.
- Advise that dogs and cats have their teeth brushed daily.
- Be sympathetic to clients that are unable to brush their pet's teeth and suggest alternatives (see Q35).
- Suggest feeding a special diet such as Hills T/D which gently and mechanically cleans the teeth (and has the added advantage that brushing can be reduced to twice weekly).
- Send out dental reminders to encourage professional, regular oral examination.
You are discharging a Staffie following a dental, and have started to discuss the merits of tooth brushing at home. The client stops you mid-flow and says that it is simply impossible to get Spike to stay in the room when the toothpaste appears, let alone hold him down for the duration of a clean! What advice would you recommend?
- Be sympathetic and aware that clients are sometimes daunted by things that we might take for granted.
- Demonstrate the procedure on a well-manner dog belonging to a member of staff to show that tooth brushing can be well tolerated and is relatively quick and simple.
- Suggest that Spike finds a toothpaste that he likes the flavour of. There are several brands available, and flavours range from poultry for the meat lover to sweet smelling biscuit. Keep a variety for sampling and see which one Spike likes to lick off of your fingers.
- The next stage is for Spike to associate the taste of the toothpaste with pleasurable experiences. If he has a favourite toy such as a Kong or tug rope, then this can be smeared with toothpaste. Brands such as Logic do not even require the teeth to be brushed (although its action is greatly enhanced if this can be achieved).
- Once Spike is comfortable with playing with toothpaste covered toys and happily licking it from the owner's fingers, then it is time to see if he will tolerate gently having his teeth and gums rubbed with toothpaste applied by a finger.
- Once he is happy with this step, then the owner can progress to a finger brush and finally a proper toothbrush. Special veterinary brushes are best as they are angled to allow easier access to an animal's mouth.
- Advise that it may take some time to achieve the goal, and that meanwhile other options are available. These range from Pedigree Denta-Rasks to Hills T/D diet.

Veterinary Dentistry

Arlo Guthrie — Tue, 21 Apr 2009 08:58:32 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:58:32

QUESTIONS

What is the difference between plaque and tartar?
What is another name for tartar?
List 10 signs that may be present in an animal suffering from dental disease.
What is the irreversible stage of periodontal disease called?
State 4 complications associated with dental extractions.
At what age are the deciduous teeth lost in cats and dogs?
At what age is permanent dentition complete in cats and dogs?
How many teeth do adult cats and dogs possess?
How many teeth do puppies and kittens possess?
What teeth are present in cats and dogs, but not in rabbits?
How many roots are possessed by the carnassials?
Why should dental scaling never be performed at the same time as other surgery?
For how long should the tip of the ultrasonic scaler be in continuous contact with the tooth?
For what purpose is prophy polish employed?
What is malocclusion?
What is another name for normal occlusion?
What is prognathism?
State 2 breeds of dog affected by prognathism.
What is brachygnathism?
State 2 breeds of dog in which brachygnathism is often seen.
What is wry bite?
What is the term used to describe the occurrence of some of the upper incisors resting caudal to the lower incisors?
What instruments might you use to loosen a tooth prior to extraction?
What instrument would you choose to extract a retained deciduous tooth?
Describe probe evaluation of periodontal disease.
What is a gingivectomy?
Why is the mouth a major source of disease affecting the heart, liver and kidneys?
What is the correct name for a tooth socket?
What is the correct name for the alveolar lining?
What is the pellicle?
What is the zone where the crown and the root of the tooth meet?
What substances make up the periodontal ligament?
List ways in which the safety and comfort of both operator and patient can be ensured during dental prophylaxis?
List ways in which you can encourage owners to ensure a good level of home dental care.
You are discharging a Staffie following a dental, and have started to discuss the merits of tooth brushing at home. The client stops you mid-flow and says that it is simply impossible to get Spike to stay in the room when the toothpaste appears, let alone hold him down for the duration of a clean! What advice would you recommend?

Surgical Correction Of Other Conditions - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:57:42 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:57:42

ANSWERS

Name 2 congenital deformities affecting the mouth that usually result in euthanasia.
- Cleft palate.
- Hare lip.
If the puppy or kitten survives to 3 months, then corrective surgery may be carried out, but generally these animals are unable to suckle and therefore it is considered sensible to perform humane destruction.
What is the name of the condition associated with bacterial infection of the jowls?
Labial dermatitis.
Why should fish hooks lodged in the oral cavity be removed with caution?
They possess a barb and therefore need to be cut rather than simply pulled through.
Give 2 examples of complications associated with oesophageal foreign bodies.
- Oesophagitis as a result of trauma.
- Infection introduced via a penetrative injury or from incomplete removal of the foreign body.
Complications are often seen in cases of stick injury since the wood often splinters.
What is the name of the condition characterised by flaccid dilation of the oesophagus?
Megaoesophagus.
What is gastric dilation?
A serious condition in which the stomach fills up with gas and swells to enormous proportions.
What is gastric torsion?
This occurs when a build up of gas in the stomach is unable to escape as a result of the stomach twisting around in the abdomen and knotting the cardia and pylorus together thus occluding both the entrance and exit.
Describe the first aid treatment of gastric dilation.
- Calm and restrain the patient.
- Time is of the essence so do not waste it by looking around for protective clothing.
- Attempt to release the gas pressure by passing a lubricated stomach tube down the oesophagus.
- If this is unsuccessful the left side of the abdomen may be pierced with a 16g needle at the point of maximum distension. Do not allow the stomach to deflate too rapidly.
- Treat shock.
- Prepare for emergency surgery if unsuccessful in releasing the gas.
These procedures may only be carried out as a life saving emergency measure in cyanosed animals. The consent of the veterinary surgeon should be obtained prior to commencement.
What is another name for gastric dilation?
Volvulus syndrome or gastric dilation volvulus (GDV).
Give 2 examples of breeds commonly affected by GDV?
- Great Dane
- Irish wolf hound.
What is a common complication of GDV?
Cardiac arrhythmia (this often occurs 12-24 hours following surgery and therefore monitoring by auscultation or ECG is sensible).
List 5 ways in which the risk of GDV can be minimised.
- The feeding of several small meals per day rather than one large one.
- Ensure that the dog is rested for at least 1-2 hours following a meal.
- Feed a high quality meatbased rather than cerealbased diet.
- Soak dry food.
- Raise the food bowl in order to prevent aerophagia.
What is endoscopy?
A non-invasive technique used to visualise body cavities and hollow organs by use of a fibre-optic light source combined with optical systems of lenses and mirrors.
What is the name of the congenital deformity in which the pylorus is unable to function normally?
Pyloric stenosis.
What is the name of the surgery performed to remove a foreign body from the small intestine?
Enterotomy via laporotomy.
What is the name of the surgical procedure that involves resection of a part of the intestine in cases of severe bowel damage?
Enterectomy.
What is intussusception?
The telescoping of one section of the bowel into an adjoining portion.
What species is most commonly affected by intussusception, and what age are these animals usually?
Cats; usually under 2 years old.
By what name is the surgical correction of intussusception known?
End-to-end anastomosis.
What is proctoscopy?
Examination of the rectum using a proctoscope (an illuminated speculum that aids visualisation by dilating the rectum with air).
List 5 possible causes of constipation.
- Enlarged prostate.
- Rectal tumour.
- Perineal hernia.
- Narrow pelvic canal.
- Fractured pelvis.
List 4 methods by which constipation can be treated.
- Manual evacuation.
- Administration of enemata.
- Administration of laxatives.
- Concurrent treatment of the inciting cause.
What type of suture may be used following the replacement of a prolapsed rectum in order to help retain it in place?
Purse string suture.
What is the name of the congenital condition in which the anus fails to unite with the rectum?
Imperforate anus.
List considerations to be taken into account when nursing a dog following surgical removal of the anal sacs.
- Defecation may be painful, therefore feed a bland diet little and often.
- Faecal softeners may be indicated (such as Peridale).
- Some dogs may experience faecal incontinence for a few days. This may be a long-term problem, but luckily is rare.
- The dog is VERY likely to interfere with the wound and an Elizabethan collar is essential.
- Analgesia and antibiotic therapy are usually indicated.
What is the name of the deep chronic infection of skin surrounding the anus, characterised by irritation, odour and the formation of sinuses and fistulae?
Anal furunculosis.
What breed of dog is predisposed to anal furunculosis?
The German Shepherd.
What is the name given to the procedure involving the destruction of living tissue by use of controlled applications of extreme cold? (A common method of treating anal furunculosis).
Cryosurgery.
Give 3 examples of gases which when converted to their liquid state are suitable for cryosurgery.
- Carbon dioxide.
- Nitrogen.
- Nitrous oxide.
The veterinary surgeon is using liquid nitrogen for cryosurgery. What is the minimum temperature that must be achieved for efficient results?
At least -20°C.
What is a dewar?
A large bodied, narrow necked metal container with a loose-fitting stopper; used to store liquid gas for cryosurgery.
State 4 risks associated with cryosurgery.
- The danger of cold burn to personnel.
- The danger of cold burn to the patient.
- Evaporation.
- Explosion (never store liquid gases in tightly sealed containers)
What is laryngeal paralysis?
Inability to dilate the rima glottidis due to paralysis of the laryngeal muscles. The cause is unknown, and the disease often affects large breeds of dogs in old age. The condition is usually bilateral (unilateral in horses).
Laryngeal paralysis is irreversible, but certain treatments may assist respiration. Can you name them?
- Treatment with steroids in the early stages.
- Surgery to open the airway; this is called unilateral arytenoid lateralisation (or more commonly, "laryngeal tie-back").
State 2 dog breeds that are prone to laryngeal paralysis.
- Irish setter.
- Labrador retriever.
What is the difference between a tracheostomy and a tracheotomy?
A tracheostomy is a technique for creating a permanent opening into the trachea in order to bypass an obstruction, whilst a tracheotomy is a life-saving temporary opening performed in the event of acute upper away obstruction.
Tracheostomies are rarely indicated in veterinary medicine.
What does BAOS stand for?
Brachycephalic airway obstruction syndrome.
List the 6 main problems that together contribute to BAOS.
- Narrow nares.
- Narrow nasal cavity.
- Narrow pharynx.
- Overlong soft palate.
- Overlong tongue.
- Hypoplastic trachea.
What is the name given to a temporary surgical opening into the thorax performed in order to facilitate surgery on the intrathoracic organs?
Thoracotomy.
Thoracotomy can be approached in one of 3 ways. State them.
- Incision through the intercostal muscles (the most commonly used technique in cats and dogs).
- Rib resection and incision of the underlying periosteum and pleura.
- Sternotomy (splitting of the sternum).
How soon can a chest drain be removed following thoracotomy?
Usually after a few hours.
What is the name that describes the complete removal of a kidney?
Nephrectomy.
Give 3 reasons as to why a nephrectomy may be indicated.
- Neoplasia.
- Chronic nephritis.
- Hydronephrosis.
What is hydronephrosis?
The accumulation of urine in the pelvis of the kidney which results in atrophy of the kidney structure.
List 3 possible causes of hydronephrosis.
- Congenital malformation.
- Acquired as a result of obstruction by a tumour or urolith.
- Back pressure as a result of stricture of the urethra or enlarged prostate.
What is the name that describes the surgical removal of a kidney and its ureter?
Ureteronephrectomy.
What is the name of the condition in which the ureter/s insert further down the urinary tract than normal, causing urinary incontinence?
Ureteric ectopia, or more commonly known as ectopic ureters.
State breed of dog suffers most commonly from ectopic ureter.
- Labrador retriever.
What is a cystotomy?
A surgical procedure involving the opening up of the bladder; usually to remove uroliths.
What is the term that describes the removal of urethral calculi by forcible injection of sterile saline via urethral catheterisation?
Retropulsion.
What is the safest way in which to relieve a cat suffering from a blocked bladder if minimal help is available?
Cystocentesis (see General Nursing chapter).
What is the common name for bilateral orchidectomy?
Castration.
What is the common name for ovariohysterectomy?
Spaying.
What is pyometra?
Accumulation of pus in the uterus; this may be "open" or "closed". A closed pyometra can be fatal and requires immediate surgery.
What is the correct term used to describe Caesarean section performed to relieve dystocia due to uterine inactivity or foetal obstruction?
Hysterotomy.
What hormone is responsible for causing vaginal hyperplasia?
Oestrogen.
Give 4 examples when the use of ultrasound might be indicated.
- Pregnancy diagnosis.
- Evaluation of the reproductive tract.
- Echocardiography - investigation of cardiac function.
- Evaluation of the architecture of parenchymal organs such as the liver, spleen and kidneys.

Surgical Correction Of Other Conditions

Arlo Guthrie — Tue, 21 Apr 2009 08:56:55 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:56:55

QUESTIONS

Name 2 congenital deformities affecting the mouth that usually result in euthanasia.
What is the name of the condition associated with bacterial infection of the jowls?
Why should fish hooks lodged in the oral cavity be removed with caution?
Give 2 examples of complications associated with oesophageal foreign bodies.
What is the name of the condition characterised by flaccid dilation of the oesophagus?
What is gastric dilation?
What is gastric torsion?
Describe the first aid treatment of gastric dilation.
What is another name for gastric dilation?
Give 2 examples of breeds commonly affected by GDV?
What is a common complication of GDV?
List 5 ways in which the risk of GDV can be minimised.
What is endoscopy?
What is the name of the congenital deformity in which the pylorus is unable to function normally?
What is the name of the surgery performed to remove a foreign body from the small intestine?
What is the name of the surgical procedure that involves resection of a part of the intestine in cases of severe bowel damage?
What is intussusception?
What species is most commonly affected by intussusception, and what age are these animals usually?
By what name is the surgical correction of intussusception known?
What is proctoscopy?
List 5 possible causes of constipation.
List 4 methods by which constipation can be treated.
What type of suture may be used following the replacement of a prolapsed rectum in order to help retain it in place?
What is the name of the congenital condition in which the anus fails to unite with the rectum?
List considerations to be taken into account when nursing a dog following surgical removal of the anal sacs.
What is the name of the deep chronic infection of skin surrounding the anus, characterised by irritation, odour and the formation of sinuses and fistulae?
What breed of dog is predisposed to anal furunculosis?
What is the name given to the procedure involving the destruction of living tissue by use of controlled applications of extreme cold? (A common method of treating anal furunculosis).
Give 3 examples of gases which when converted to their liquid state are suitable for cryosurgery.
The veterinary surgeon is using liquid nitrogen for cryosurgery. What is the minimum temperature that must be achieved for efficient results?
What is a dewar?
State 4 risks associated with cryosurgery.
What is laryngeal paralysis?
Laryngeal paralysis is irreversible, but certain treatments may assist respiration. Can you name them?
State 2 dog breeds that are prone to laryngeal paralysis.
What is the difference between a tracheostomy and a tracheotomy?
What does BAOS stand for?
List the 6 main problems that together contribute to BAOS.
What is the name given to a temporary surgical opening into the thorax performed in order to facilitate surgery on the intrathoracic organs?
Thoracotomy can be approached in one of 3 ways. State them.
How soon can a chest drain be removed following thoracotomy?
What is the name that describes the complete removal of a kidney?
Give 3 reasons as to why a nephrectomy may be indicated.
What is hydronephrosis?
List 3 possible causes of hydronephrosis.
What is the name that describes the surgical removal of a kidney and its ureter?
What is the name of the condition in which the ureter/s insert further down the urinary tract than normal, causing urinary incontinence?
State breed of dog suffers most commonly from ectopic ureter.
What is a cystotomy?
What is the term that describes the removal of urethral calculi by forcible injection of sterile saline via urethral catheterisation?
What is the safest way in which to relieve a cat suffering from a blocked bladder if minimal help is available?
What is the common name for bilateral orchidectomy?
What is the common name for ovariohysterectomy?
What is pyometra?
What is the correct term used to describe Caesarean section performed to relieve dystocia due to uterine inactivity or foetal obstruction?
What hormone is responsible for causing vaginal hyperplasia?
Give 4 examples when the use of ultrasound might be indicated.

Surgical Correction Of Eye & Ear Conditions - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:53:40 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:53:40

ANSWERS

List 5 possible causes of conjunctivitis.
- Infection.
- Foreign body.
- Entropion.
- Ectropion.
- Inflammatory disease of the eyeball.
What is keratitis?
Inflammation of the cornea.
What is the name of the surgical procedure used to protect the cornea following ulceration?
Third eyelid flap.
What alternative to a third eyelid flap is available?
Insertion of a bandage lens.
State 3 advantages of bandage lenses.
- They are transparent and therefore allow visualisation.
- It is possible to place them consciously.
- A variety of different sizes are available to suit most cats and dogs.
State 2 disadvantages of bandage lenses.
- Some animals do not tolerate them.
- They can fall out un-noticed by the owner.
What is the difference between entropion and ectropion?
Entropion is inversion of the eyelid margin causing the eyelashes to rub on the cornea, whilst ectropion is eversion of the eyelid margin and rarely requires surgical attention.
State the breed of dog that is most prone to entropion.
The Shar pei.
What name describes the abnormal growth of hairs at the eyelid margin?
Distichiasis.
What technique is used to correct distichiasis and remove small tumours from the eyelid margin?
Electrocautery.
What is another term for electrocautery?
Diathermy.
Describe a cataract.
Opacity of the crystalline lens of the eye causing partial or complete blindness. In some cases, surgical correction is possible. The cause may be congenital, or as a result of injury or diabetes mellitus.
What popular children's pet is prone to prolapse of the eyeball?
The hamster.
What type of dog is prone to prolapse of the eyeball?
Brachycephalic breeds, especially the bulldog.
Describe the first aid treatment that you would administer to a patient suffering from a prolapsed eyeball.
- Restrain and calm the patient.
- Cleanse the eyeball with saline.
- Lubricate with K-Y jelly.
- Very gently attempt to retract eyelid and see if eyeball relocates unassisted, otherwise do no more.
- If unsuccessful, gently support the eyeball with saline soaked swabs or preferably cover the eyeball in sterile KY jelly until help arrives.
- Monitor for signs of shock and treat accordingly.
- Administer systemic and topical antibiotics in accordance with the veterinary surgeon's instructions.
Describe the first aid treatment that you would administer to a patient suffering chemical irritation of the eye following contact with a noxious substance.
- Restrain and calm the patient.
- Adorn protective apron, gloves and mask.
- Irrigate the eye with copious amounts of water or saline.
- Consult the COSHH manual for further advice if the name of the substance is known.
- Monitor for signs of shock and treat accordingly.
- Keep the animal warm and quiet until the veterinary surgeon can attend the case.
What is an aural haematoma? (also see Module 2 of this chapter: Q16-18).
A discrete collection of blood that accumulates on either side of the pinna; usually secondary to otitis.
List 5 possible causes of otitis.
- Foreign body in the ear canal.
- Ear mites.
- Bacterial or fungal infection.
- Extension of generalised skin disease.
- Poor ear conformation.
List 4 breeds of dog that are particularly susceptible to otitis.
- Bassett hound.
- English springer spaniel.
- English setter.
- Cavalier King Charles spaniel.
There are 3 types of otitis. Briefly describe each.
- Otitis externa - inflammation of the external auditory meatus.
- Otitis media - inflammation of the middle ear cavity.
- Otitis interna - inflammation of the inner ear.
Of your answers to Q18, which type of otitis affects the organs of balance and may cause head tilts?
Otitis interna.
What is a lateral wall resection?
The removal of the lateral portion of the ear canal in order to improve drainage and air circulation.
What is the difference between a vertical ear canal ablation (VCA) and a total ear canal ablation (TECA)?
A VCA involves only removal of the vertical portion of the ear canal, whilst a TECA is more radical and involves resection of both the vertical and horizontal parts of the ear canal. Both serve to remove diseased tissue in cases of chronic infection.

Surgical Correction Of Eye & Ear Conditions

Arlo Guthrie — Tue, 21 Apr 2009 08:52:58 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:52:58

QUESTIONS

List 5 possible causes of conjunctivitis.
What is keratitis?
What is the name of the surgical procedure used to protect the cornea following ulceration?
What alternative to a third eyelid flap is available?
State 3 advantages of bandage lenses.
State 2 disadvantages of bandage lenses.
What is the difference between entropion and ectropion?
State the breed of dog that is most prone to entropion.
What name describes the abnormal growth of hairs at the eyelid margin?
What technique is used to correct distichiasis and remove small tumours from the eyelid margin?
What is another term for electrocautery?
Describe a cataract.
What popular children's pet is prone to prolapse of the eyeball?
What type of dog is prone to prolapse of the eyeball?
Describe the first aid treatment that you would administer to a patient suffering from a prolapsed eyeball.
Describe the first aid treatment that you would administer to a patient suffering chemical irritation of the eye following contact with a noxious substance.
What is an aural haematoma? (also see Module 2 of this chapter: Q16-18).
List 5 possible causes of otitis.
List 4 breeds of dog that are particularly susceptible to otitis.
There are 3 types of otitis. Briefly describe each.
Of your answers to Q18, which type of otitis affects the organs of balance and may cause head tilts?
What is a lateral wall resection?
What is the difference between a vertical ear canal ablation (VCA) and a total ear canal ablation (TECA)?

Hernias & Ruptures - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:51:35 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:51:35

ANSWERS

What is a hernia?
An abnormal protrusion of any part of the internal organs from the structures enclosing them.
What is a rupture?
A pathological tear in the lining of a cavity through which the enclosed organs may protrude.
What is the name given to a hernia or rupture that can be repaired by returning the affected organ to its original location via the defect itself?
Reducible.
What is the name of the membrane that may be ruptured in cases of severe otitis externa?
The tympanic membrane.
State 2 sites that may be subject to rupture (other than your answer to Q4).
- Diaphragm.
- Perineum.
What part of the body is the most common site for incidences of herniation?
The abdominal cavity.
What is another term used to describe an irreducible hernia?
Incarcerated.
What is the most likely reason preventing the replacement of herniated organs?
The formation of adhesions (usually in chronic cases).
What is the term that describes the devitalisation of the contents of a hernia or rupture due to the entrapment of blood vessels passing through the defect?
Strangulated.
What is the name of the type of hernia that is often congenital?
Umbilical.
Are inguinal hernias more common in dogs or bitches?
Bitches.
What techniques may be used in order to achieve reduction following herniation?
- Elongation of the defect.
- Breaking down adhesions.

Hernias & Ruptures

Arlo Guthrie — Tue, 21 Apr 2009 08:50:59 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:50:59

QUESTIONS

What is a hernia?
What is a rupture?
What is the name given to a hernia or rupture that can be repaired by returning the affected organ to its original location via the defect itself?
What is the name of the membrane that may be ruptured in cases of severe otitis externa?
State 2 sites that may be subject to rupture (other than your answer to Q4).
What part of the body is the most common site for incidences of herniation?
What is another term used to describe an irreducible hernia?
What is the most likely reason preventing the replacement of herniated organs?
What is the term that describes the devitalisation of the contents of a hernia or rupture due to the entrapment of blood vessels passing through the defect?
What is the name of the type of hernia that is often congenital?
Are inguinal hernias more common in dogs or bitches?
What techniques may be used in order to achieve reduction following herniation?

Dressing An Ear - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 08:50:18 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:50:18

Dressing An Ear - Practical Task

Dressing an ear following surgical drainage of an aural haematoma

Key pointers

Make sure that you are dressing the correct part of the anatomy.
Make sure that you know your anatomical directions.
Know your left from your right!
Don't forget to talk to conscious patients; even if it is a cuddly toy in the exam!
Adorn protective clothing if provided.
Select the appropriate equipment before you begin and logically think over the procedure in your head before setting to work.
Remember that in many situations where you are required to dress a wound, there may be more than 1 example of appropriate materials. In such circumstances, it is up to you to make a sensible choice, even though there may be no specific right or wrong answer. The selection of dressing materials is often dictated in practice not only by the type and severity of the wound, but also by cost and personal preference.

Practical examination example:
An English springer spaniel has had an aural haematoma drained under local anaesthetic. The veterinary surgeon has asked you to apply a dressing (the incision for drainage is on the ventral aspect of the right pinna. Demonstrate how you would do so (you are given a large cuddly toy upon which to work).

Suggested Equipment

Apron and gloves
Antiseptic solution for cleansing
Swabs
Straight Mayo scissors
Cotton wool
Rondopad
5cm Knitfirm
5cm Co-flex

Procedure

Introduce yourself calmly and confidently to the patient.
Ask an assistant to restrain the patient. He may be held in left lateral recumbency, but a conscious animal will probably tolerate sitting or standing rather better than being made to lie down.
Adorn protective apron and gloves if provided.
Assess the surgical wound. Although you are dealing with a toy dog, imagine it to be a real patient. Cleanse away any discharge gently with a suitable antiseptic solution such as dilute chlorhexidine (Hibiscrub) and cotton wool. Ensure that the area to be dressed is then carefully dried.
Apply a pad of cotton wool to the top of the dog's head and fold the pinna of the right ear back onto it.
Next select a suitable dressing. A non-adherent dry dressing (a cotton acrylic fibre pad with a perforated polyester film such as Rondopad) is ideal. These dressings come in various sizes, but can be cut to fit any shape or size of wound. Place the dressing gently over the incision remembering to place it shiny side down, in a sterile fashion.
Place a pad of cotton wool on top to absorb excessive exudate. Extend the padding around the head to ensure comfort.
Secure the padding with conforming bandage. 5cm Knitfirm is suitable. This should be applied in a figure-of-8 pattern passing under the chin, and anchoring upon either side of the free ear to prevent the dressing from slipping.
Now select a suitable TERTIARY LAYER (the most exterior part of the dressing). Conforming, cohesive bandage such as Co-flex is ideal. 5 or 7.5cm are suitably sized. Cohesive dressings do not stick to the fur itself and therefore allow the dressing to be removed without pulling away large clumps of fur. It is essential that the dressing is not too tight. The dog should be able to open its mouth normally and respiration must not be obstructed.
Check that the dressing is smooth and comfortable.
Make sure that you can answer the following questions:
i) How can patient interference be prevented? (see the Q & A section of this module).
ii) What advice should the owner be given upon discharge of the dog? (see Key Notes 1 & 2 of this module).
iii) What is the main disadvantage of the application of an ear dressing following the drainage of a haematoma? (Many aural haematomas are secondary to infections of the ear canal such as otitis. These generally require both topical and systemic antibiotic therapy - it is impossible to apply ear drops through an ear dressing of this nature without first removing it!).

Dressing An Ear - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 08:49:28 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:49:28

Dressing an ear following surgical drainage of an aural haematoma

Key pointers

Make sure that you are dressing the correct part of the anatomy.
Make sure that you know your anatomical directions.
Know your left from your right!
Don't forget to talk to conscious patients; even if it is a cuddly toy in the exam!
Adorn protective clothing if provided.
Select the appropriate equipment before you begin and logically think over the procedure in your head before setting to work.
Remember that in many situations where you are required to dress a wound, there may be more than 1 example of appropriate materials. In such circumstances, it is up to you to make a sensible choice, even though there may be no specific right or wrong answer. The selection of dressing materials is often dictated in practice not only by the type and severity of the wound, but also by cost and personal preference.

Suggested Equipment

Apron and gloves
Antiseptic solution for cleansing
Swabs
Straight Mayo scissors
Cotton wool
Rondopad
5cm Knitfirm
5cm Co-flex

Procedure

Introduce yourself calmly and confidently to the patient.
Ask an assistant to restrain the patient. He may be held in left lateral recumbency, but a conscious animal will probably tolerate sitting or standing rather better than being made to lie down.
Adorn protective apron and gloves if provided.
Assess the surgical wound. Although you are dealing with a toy dog, imagine it to be a real patient. Cleanse away any discharge gently with a suitable antiseptic solution such as dilute chlorhexidine (Hibiscrub) and cotton wool. Ensure that the area to be dressed is then carefully dried.
Apply a pad of cotton wool to the top of the dog's head and fold the pinna of the right ear back onto it.
Next select a suitable dressing. A non-adherent dry dressing (a cotton acrylic fibre pad with a perforated polyester film such as Rondopad) is ideal. These dressings come in various sizes, but can be cut to fit any shape or size of wound. Place the dressing gently over the incision remembering to place it shiny side down, in a sterile fashion.
Place a pad of cotton wool on top to absorb excessive exudate. Extend the padding around the head to ensure comfort.
Secure the padding with conforming bandage. 5cm Knitfirm is suitable. This should be applied in a figure-of-8 pattern passing under the chin, and anchoring upon either side of the free ear to prevent the dressing from slipping.
Now select a suitable TERTIARY LAYER (the most exterior part of the dressing). Conforming, cohesive bandage such as Co-flex is ideal. 5 or 7.5cm are suitably sized. Cohesive dressings do not stick to the fur itself and therefore allow the dressing to be removed without pulling away large clumps of fur. It is essential that the dressing is not too tight. The dog should be able to open its mouth normally and respiration must not be obstructed.
Check that the dressing is smooth and comfortable.
Make sure that you can answer the following questions:
i) How can patient interference be prevented? (see the Q & A section of this module).
ii) What advice should the owner be given upon discharge of the dog? (see Key Notes 1 & 2 of this module).
iii) What is the main disadvantage of the application of an ear dressing following the drainage of a haematoma? (Many aural haematomas are secondary to infections of the ear canal such as otitis. These generally require both topical and systemic antibiotic therapy - it is impossible to apply ear drops through an ear dressing of this nature without first removing it!).

Abscesses, Ulcers & Haematomas - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:47:31 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:47:31

ANSWERS

What is an abscess?
A localised inflammatory reaction with a necrotic, pus-filled centre.
What are the 2 terms that describe the presence of pus?
- Purulent.
- Suppurative.
What does pus consist of?
Liquefied dead tissue mixed with large numbers of dead or dying polymorphonuclear leukocytes.
List 8 clinical signs or symptoms that may be present in a cat suffering from an abscess caused by a bite.
- Swelling/inflammation.
- Bite marks.
- Hair loss.
- Odour.
- Pyrexia.
- Anorexia.
- Pain/aggression.
- Leukocytosis initially followed by a monocytosis after about 4-5 days.
Why do bite wounds commonly lead to abscess formation?
Due to the large amount of bacteria present in the oral cavity. Cats in particular carry Pastuerella multocida, which can be particularly nasty.
Describe the equipment that you would prepare for the treatment of a "ripe" cat bite abscess (not including any premedicant or anaesthetic equipment).
- Protective gloves, apron and mask.
- Clippers.
- Water-soluble lubricating gel to protect the wound whilst clipping.
- Skin antiseptic such as chlorhexidine.
- Cotton wool.
- Size 15 scalpel blade for lancing.
- Syringe for flushing.
- Absorbent material to collect the expressed pus.
- Swab in charcoal transport medium (if culture and sensitivity is required).
- Clinical waste sack into which infected material is disposed of.
- Injectable antibiotic and analgesic with suitable sized needles and syringes.
What is meant by a "cold" abscess?
An abscess that is characterised by a thick fibrous wall enclosing granulation tissue.
Why might a cold abscess develop?
A cold abscess may develop as a result of chronic infection due to inadequate drainage or the failure to remove the inciting cause. It may also occur in deep tissue where there is no route for drainage.
Describe how a cold abscess is treated.
Complete surgical excision.
What species do cold abscesses commonly affect?
These can occur in all species, but are particularly common in rabbits. Rabbit abscesses develop largely in the head area and are often associated with dental problems.
What is an ulcer?
Local excavation of the surface of an organ or tissue resulting from the sloughing of necrotic tissue.
Give 4 sites of the body where an ulcer might develop and give a possible cause of each.
- The cornea of the eye - cat scratch.
- The oral cavity - feline herpes virus.
- The stomach - reaction to NSAIDs.
- The skin - bed sores in long-term hospitalised animals.
What is the correct term used to describe a "bed sore"?
Decubitus ulcer.
What is a rodent ulcer?
An erosive lesion most commonly affecting the upper lip in cats. Also known as eosinophilic granuloma.
What is a haematoma?
A swelling caused by extravasated blood; result of injury to the blood vessels or a clotting disorder.
Briefly describe 3 possible treatments of an aural haematoma?
- Drainage via needle and syringe followed by injection of a steroid such as Voren into the pinna (this can usually be done consciously).
- Drainage via an incision made with a scalpel blade under general anaesthetic.
- Drainage via either of the methods described above followed by the suturing of buttons to the pinna to help prevent recurrence.
What is the name of the type of bandage often used to prevent patient mutilation following treatment of an aural haematoma?
A figure of 8 head bandage.
What is the most common cause of aural haematomas in dogs?
A dog may shake its head as a result of an ear infection such as otitis externa. The resultant trauma then can lead to the formation of a haematoma, particularly if the dog hits its head whilst it is shaking.

Abscesses, Ulcers & Haematomas

Arlo Guthrie — Tue, 21 Apr 2009 08:46:30 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:46:30

QUESTIONS

What is an abscess?
What are the 2 terms that describe the presence of pus?
What does pus consist of?
List 8 clinical signs or symptoms that may be present in a cat suffering from an abscess caused by a bite.
Why do bite wounds commonly lead to abscess formation?
Describe the equipment that you would prepare for the treatment of a "ripe" cat bite abscess (not including any premedicant or anaesthetic equipment).
What is meant by a "cold" abscess?
Why might a cold abscess develop?
Describe how a cold abscess is treated.
What species do cold abscesses commonly affect?
What is an ulcer?
Give 4 sites of the body where an ulcer might develop and give a possible cause of each.
What is the correct term used to describe a "bed sore"?
What is a rodent ulcer?
What is a haematoma?
Briefly describe 3 possible treatments of an aural haematoma?
What is the name of the type of bandage often used to prevent patient mutilation following treatment of an aural haematoma?
What is the most common cause of aural haematomas in dogs?

Dressing A Surgical Wound - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 08:45:26 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:45:26

When dressing an area of the body, remember:

Make sure that you are dressing the correct part of the anatomy.
Make sure that you know your anatomical directions.
Know your left from your right!
Don't forget to talk to the conscious patients.
Adorn protective clothing if provided.
Select the appropriate equipment before you begin and logically think over the procedure in your head before setting to work.
Remember that in many situations where you are required to dress a wound, there may be more than 1 example of appropriate materials. In such circumstances, it is up to you to make a sensible choice, even though there may be no specific right or wrong answer. The selection of dressing materials is often dictated in practice not only by the type and severity of the wound, but also by cost and personal preference.

Practical examination example:

A Boxer dog has had a general anaesthetic to suture a wound to the palmar aspect of his left paw. The veterinary surgeon has asked you to dress the surgical wound. Demonstrate how you would do so (you are given a large cuddly toy upon which to work).

Suggested Equipment

Apron and gloves
Antiseptic solution for cleansing
Straight Mayo scissors
Cotton wool
Rondopad
5cm Soffban
5cm Knitfirm
5cm Co-flex
2.5cm Elastoplast

Procedure

Ask an assistant to monitor the dog's vital signs since he is still under general anaesthetic.
Adorn protective apron and gloves if provided.
Assess the surgical wound. Although you are dealing with a toy dog, imagine it to be a real patient. In real life you would check that the sutures are apposed and that there is no haemorrhage.
Take some cotton wool and break off some small strips to place between the digits, pads and dew claws. This helps to prevent the toes from chafing and absorbs sweat produced.
Next select a suitable material for the dressing which comes into contact with the wound. A clean, sutured wound is most suited to a non-adherent dry dressing (a cotton acrylic fibre pad with a perforated polyester film such as Rondopad). These dressings come in various sizes, but can be cut to fit any shape or size of wound. Place the dressing, in a sterile fashion, gently over the sutures remembering to place it shiny side down.
Next apply a PRIMARY PADDING LAYER. A sutured wound to the pad is likely to need some padding in order to provide protection when the dog walks, but not so much that the dressing is likely to easily be pulled off. 5cm Cellona orthopaedic padding or Soffban is ideal for a Boxer sized dog and has the advantage over cotton wool that it comes ready to use in an easy to apply roll.
Next secure the dressing and primary layers with cotton conforming bandage (the SECONDARY LAYER: 5 or 7.5cm Knitfirm is suitable). Apply the bandage longitudinally to the cranial and caudal surface of the limb and then turn it to wind around the limb in a figure-of-8 pattern. This serves to ensure that there is an even tension throughout the bandage. Use the carpus as an anchor in order to ensure that the dressing stays in place. Always bandage distal to proximal limb.
Now select a suitable TERTIARY LAYER (the most exterior part of the dressing). Conforming, cohesive bandage such as Co-flex is ideal. 5 or 7.5cm are suitably sized. Cohesive dressings do not stick to the fur itself and therefore allow the dressing to be removed without pulling away large clumps of fur. The disadvantage is that sometimes they can be too easily removed. Never be tempted to apply sticky tape to the top of the bandage onto the pet's fur. It is very important that this layer of the dressing is not applied too tightly. Pull out a length of Co-flex prior to use in order to prevent this. An overly tight dressing can cause circulation problems and if not enough blood is getting to the wound, then healing may be impaired.
Check that the dressing is smooth and comfortable. Ensure that the tertiary layer covers the intermediate layers. The padding layer should always be visible at the top of the bandage to ensure comfort and prevent soreness through rubbing.
Make sure that you can answer the following questions:
i) How can patient interference be prevented? (see the Q & A section of this module)
ii) What advice should the owner be given upon discharge of the dog? (see Key Notes A & B of this module).

Care Of Dressings & Bandages - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 08:44:23 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:44:23

Care Of Dressings & Bandages - Key Notes

This is an example of a client information sheet that may be useful when discharging a patient with a dressing.

Patient………………………………… Date………………………..

All bandages and dressings must be checked regularly at the surgery so please keep re-examination appointments.

PLEASE ENSURE THAT:
Dressings are kept clean and dry. If you wish to take your pet outside, bandages covering the foot should be protected by a plastic bag. The bag must be removed as soon as your pet returns indoors to prevent the foot from sweating and the dressing becoming wet.

CONTACT THE SURGERY IF:
Your pet is interfering with its dressing/bandage.
The area around the dressing is swollen.
The area around the dressing is red or sore.
Toes exposed from the dressing feel cold.
An unpleasant odour emanates from the dressing.
The dressing gets wet.
The dressing appears to be slipping or chafing.
Areas of discharge or blood are evident on or around the dressing.
Your pet appears uncomfortable.

IN AN EMERGENCY - Once home, if worried, please do not hesitate to contact us.

Your pet requires an examination in ……… days time. Please ensure that you have made an appointment.

Stitches are due to be removed in ……… days time.

Care Of Dressings & Bandages - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 08:44:11 GMT

Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:44:11

This is an example of a client information sheet that may be useful when discharging a patient with a dressing.

Patient………………………………… Date………………………..

All bandages and dressings must be checked regularly at the surgery so please keep re-examination appointments.

CONTACT THE SURGERY IF:
Your pet is interfering with its dressing/bandage.
The area around the dressing is swollen.
The area around the dressing is red or sore.
Toes exposed from the dressing feel cold.
An unpleasant odour emanates from the dressing.
The dressing gets wet.
The dressing appears to be slipping or chafing.
Areas of discharge or blood are evident on or around the dressing.
Your pet appears uncomfortable.

IN AN EMERGENCY - Once home, if worried, please do not hesitate to contact us.

Your pet requires an examination in ……… days time. Please ensure that you have made an appointment.

Stitches are due to be removed in ……… days time.

General Post-Operative Care - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 08:43:04 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:43:04

This is an example of a client information sheet that may be useful following general surgery.

Patient………………………………….. Date………………………..

Your pet has received a sedative/general anaesthetic and it is possible that this may cause drowsiness. Please note that the effects of premedicant and anaesthetic drugs may remain in the body for up to 72 hours.

Wound care - If a wound is present, please discourage your pet from licking, biting or scratching since this may delay the healing process. Please check wounds daily for any signs of swelling, odour, discharge, redness or discomfort. Elizabethan collars are available from the surgery if required.
Diet - A bland meal is recommended the evening after a general anaesthetic. The surgery has provided a suitable diet, but if preferred you may offer a small proportion of your pet's regular food. It is not unusual for the appetite to be suppressed following general anaesthesia. In some cases the veterinary surgeon will advise the feeding of a special prescription diet. Full instructions will be given in such instances. Please report any incidences of vomiting or diarrhoea immediately.
Exercise - Dogs should be kept on a lead whilst outdoors until the veterinary surgeon has checked any wound. Cats should be kept indoors with a litter tray for at least 48 hours, or until the veterinary surgeon has checked any wound. Please try to keep your pet as calm as possible and prevent jumping up onto furniture or running up and down stairs.
Clipping - A small area of fur will have been clipped from the forelimb in order to facilitate the administration of an anaesthetic agent. Hair will also have been clipped from the operation site. In addition, if your pet has had a blood test, fur may have been clipped from the neck region.
Coughing - Your pet may experience a dry cough for a few days following surgery. This could be due to the insertion of an anaesthetic tube. If the cough persists or is causing distress, please contact the surgery.
IN AN EMERGENCY - Once home, if worried, please do not hesitate to contact us.

Your pet requires an examination in ……… days time. Please ensure that you have made an appointment.

Stitches are due to be removed in ……… days time.

Wound Care - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:41:35 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:41:35

ANSWERS

What is meant by inflammation?
The simple definition of inflammation is "the reaction of normal tissues to an irritant". It can be further defined as "a process which commences following an injury to the tissue and culminates in healing or the death of the damaged tissue".
State the 4 main functions of inflammatory exudate.
- The dilution of irritant substances present in the affected tissue.
- The delivery of cells involved in immune response to the affected tissue.
- The delivery of immunoglobulins to the affected tissue.
- The delivery of fibrinogen to the affected tissue.
List the 5 types of inflammatory exudate.
- Fibrinous.
- Haemorrhagic.
- Mucous.
- Purulent.
- Serous.
List the 5 cardinal signs of inflammation.
- Heat.
- Loss of normal function.
- Pain.
- Redness (erythema).
- Swelling.
NB Also look out for signs of pain (restlessness, vocalisation, anorexia etc).
List 3 systemic signs of illness that may be associated with acute inflammation.
- Leukocytosis.
- Pyrexia.
- Tachycardia.
Give 2 reasons why pain may be associated with inflammation.
- Increased pressure on nerve endings due to swelling.
- Direct irritating effect of toxins (these may be primary and arise from the actual cause of inflammation, but more commonly are a by-product of the inflammatory process itself).
Define necrosis.
Cell death, and subsequent sloughing of the affected tissue.
What is the term that describes cell death associated with the loss of local blood supply and putrefaction of the tissues by bacteria?
Gangrene.
What 2 categories of drugs are commonly used in the treatment of acute inflammation?
- Corticosteroids (eg. Prednisolone).
- Non-steroidal anti-inflammatories (eg. Ketofen).
Define chronic inflammation.
An ongoing response to persistent irritants. It is characterised by marked monocytosis and proliferation of fibroblasts.
State the 3 major categories of chronic inflammation and give an example of each.
- Persistent infection - fungal infections such as ringworm and malassezia.
- Prolonged exposure to non-degradable irritant material - reactions to inorganic foreign material
- Autoimmune disease - rheumatoid arthritis.
What are labile cells?
Cells that divide and proliferate throughout life. They are highly capable of regeneration and are therefore important in wound healing. Epithelial cells, blood cells and lymphoid tissue are all labile.
What is the difference between stable cells and permanent cells?
Stable cells are usually quiescent, but are capable of increased mitosis in response to certain stimuli, and thus may regenerate in some circumstances. Examples include the cells of bone and the endocrine glands. Permanent cells however, are only capable of mitosis in foetal life, and are unable to regenerate. Examples include neurons and cardiac muscle cells.
State 2 differences between first intention and second intention healing.
- For a wound to heal by first intention, the wound edges must be close together, whilst in second intention healing, there may be a significant amount of tissue loss.
- First intention healing is usually very much quicker than second intention healing.
What is another name that describes healing by second intention?
Granulation.
State the 3 requirements necessary for a dressing that is applied to a granulating wound.
- Moist environment.
- Warm environment.
- Reasonable absorptive capacity.
What type of wound would require a dressing that is non-adherent and provides a moist environment?
A wound healing by re-epithelialisation.
Describe 10 factors that might contribute to the breakdown of a wound or delayed healing, and describe how each might be prevented.
- Bacterial infection - antibiotic therapy; never suture an infected bite wound until the infection is under control.
- Poor aseptic technique - ensure that theatre hygiene is scrupulously maintained and that instruments are properly sterilised (see Part II - Chapter 8 - Theatre Practice).
- Reaction to suture material - ensure that appropriate materials are used and if a reaction does occur then the wound must be resutured using an alternative.
- Poor wound closure technique - ensure that sutures are not overly tight and that there is a small tissue "bite" with an appropriate distance between each. In addition, it is worth bearing in mind that continuous sutures are more likely to result in dehiscence than interrupted sutures.
- Pre-existing disease or poor general health - particular care must be taken if an animal is suffering from a condition in which the immune system is compromised such as FIV.
- Dirty or wet dressings - ensure that dressings are always kept clean and dry otherwise they can be an ideal breeding ground for bacteria.
- Drugs - some drugs such as corticosteroids, although useful in the treatment of inflammation, may delay the healing of surgical wounds, so take care in such instances. Also be cautious with regard to cytotoxics.
- Seroma formation - ensure that the patient is kept rested, ensure that great care is taken with regard to wound closure and that a drain is used if deemed necessary.
- Stress - ensure that the patient is treated with TLC and that any period of hospitalisation is made as pleasant as possible.
- Patient interference - See Q17!
List 8 ways in which a patient might be prevented from interfering with a wound.
- Elizabethan collar.
- Clean, dry dressing/s.
- Dressing of the feet to prevent injury by scratching.
- Prevention of boredom and stress as far as possible (provide stimulation for outgoing patients and quiet for nervous animals).
- Distraction (such as food/light exercise).
- Use of bitter spray (but never on an open wound as this is likely to cause irritation).
- Adequate pain relief (a patient is less likely to interfere with a non-painful wound).
- Antibiotic therapy if indicated (an infected wound is more likely to be painful; see above).
State 3 important preoperative procedures that can help to prevent the incidence of wound infection and breakdown.
- Pre-operative bathing with a suitable antiseptic solution such as chlorhexidine (Hibiscrub).
- Pre-operative clipping (ideally approximately 2 hours prior to surgery).
- Bowel preparation.
List 4 types of dressings suitable for the initial management of a contaminated wound and briefly describe each.
- Occlusive dressings - retain moisture in order to rehydrate necrotic tissue and encourage sloughing.
- Hydrogels - contribute to the rehydration of necrotic tissue but must be kept covered as they dry if left exposed to the air.
- Wet packs - gauze soaked in sterile saline (a cheap, effective, alternative to occlusive dressings and hydrogels).
- Alginate dressings - a protein based foam suitable for wounds with significant tissue loss and heavy discharge of exudate (helps with both blood clotting and wound healing).
What is a hydrocolloid?
An occlusive dressing (impervious and designed to concentrate a topical application so that it will be absorbed through the skin or to protect a wound from outside contaminants).
What type of dressing would be most suitable for a wound with light to moderate exudation?
Hydrocolloid or hydrogel.
What type of dressing would be most suitable for dressing severe burns, and why?
Alginate; burns have a very high exudation.
State the 2 broad categories of skin graft and briefly describe each.
- Skin flap - the transfer of an entire portion of skin and subcutaneous tissue complete with its own blood supply from one body area to an adjacent area.
- Free skin graft - the transfer of one or more pieces of skin with no blood supply to a clean revascularised surgical site or to a well-established bed of granulation tissue.
By what other name is a skin flap commonly known?
Pedicle graft.
State the 3 main ways in which a free skin graft can be classified.
- By source (usually autogenous ie. from skin elsewhere on the same animal).
- By thickness (split thickness or full thickness).
- By design (pinch, mesh, strip or stamp).
A split thickness graft may be harvested by using a graft knife or scalpel, but there is a specialised instrument available for this purpose. What is it called?
A dermatome.
What is the main advantage of a split thickness graft?
This type of graft will "take" more readily than a full thickness graft.
State 3 disadvantages of a split thickness graft.
- Not particularly strong.
- Poor hair growth.
- Likely to undergo contraction.
What is the function of the open spaces created by graft patterns such as mesh and strip grafts?
Drainage.
Enables a smaller size graft to be taken (eg. as the mesh/drip pattern = stretching of graft).
For how long should wound drains left in place?
Passive drains 48-72 hours.
Active drains 3-5 days (possibly longer).
Why might a drain be indicated?
- To abolish dead space.
- Therapeutic drainage of a contaminated wound.
- To remove air from a body cavity.
Give an example of a situation in which a closed passive drain might be indicated.
To collect urine from a cat with an indwelling urinary catheter following hydropropulsion.
What is the main difference between an open and a closed drain?
Open drains are always passive (rely on gravity or capillary action) whilst closed drains may be active (employing a suction device) or passive.
What is the name of the soft latex open drain commonly used in small animal wound management?
Penrose drain.
What is a sump Penrose drain?
A Foley catheter is placed within a fenestrated Penrose drain. Fluid can pass via the outside of the Foley (sump) drain, but the placement of the Penrose means that tissue cannot adhere to the Foley thus preventing continued damage. This type of drain can remain functional for long periods.
State the 3 main disadvantages of drains.
- They may provide a route for secondary infection (especially open drains).
- They are foreign bodies and their presence reduces the resistance of local tissues to infection.
- They may cause tissue damage if incorrectly placed or if unsuitable materials are used.
Give 2 examples of complications that could occur if a drain is incorrectly placed.
- Secondary haemorrhage.
- Formation of fistulae.
Briefly describe the principles of drain management.
- Document the volume/nature of exudate.
- Ensure that there is no obstruction.
- Avoid reflux of fluid when changing collection vessels as this may introduce infection.
- Ensure that dressings are changed before they become soaked in exudate.
- Maintain cleanliness around the drain and associated wound at all times.
- Observe for leakage.
- Observe for signs of local wound infection.
- Observe for signs of systemic illness.
- Shorten passive open drains to minimise the risk of accumulating infected material.
- Anchor the end of the drain to the skin to prevent it from being retracted into the wound.
- Prevent patient interference.
- Remove drains using aseptic technique.
What is the difference between a fistula and a sinus?
A fistula is an abnormal tube connecting two epithelial surfaces, whilst a sinus is a blind ended infected tract or drainage channel.

Wound Care

Arlo Guthrie — Tue, 21 Apr 2009 08:40:46 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:40:46

QUESTIONS

What is meant by inflammation?
State the 4 main functions of inflammatory exudate.
List the 5 types of inflammatory exudate.
List the 5 cardinal signs of inflammation.
List 3 systemic signs of illness that may be associated with acute inflammation.
Give 2 reasons why pain may be associated with inflammation.
Define necrosis.
What is the term that describes cell death associated with the loss of local blood supply and putrefaction of the tissues by bacteria?
What 2 categories of drugs are commonly used in the treatment of acute inflammation?
Define chronic inflammation.
State the 3 major categories of chronic inflammation and give an example of each.
What are labile cells?
What is the difference between stable cells and permanent cells?
State 2 differences between first intention and second intention healing.
What is another name that describes healing by second intention?
State the 3 requirements necessary for a dressing that is applied to a granulating wound.
What type of wound would require a dressing that is non-adherent and provides a moist environment?
Describe 10 factors that might contribute to the breakdown of a wound or delayed healing, and describe how each might be prevented.
List 8 ways in which a patient might be prevented from interfering with a wound.
State 3 important preoperative procedures that can help to prevent the incidence of wound infection and breakdown.
List 4 types of dressings suitable for the initial management of a contaminated wound and briefly describe each.
What is a hydrocolloid?
What type of dressing would be most suitable for a wound with light to moderate exudation?
What type of dressing would be most suitable for dressing severe burns, and why?
State the 2 broad categories of skin graft and briefly describe each.
By what other name is a skin flap commonly known?
State the 3 main ways in which a free skin graft can be classified.
A split thickness graft may be harvested by using a graft knife or scalpel, but there is a specialised instrument available for this purpose. What is it called?
What is the main advantage of a split thickness graft?
State 3 disadvantages of a split thickness graft.
What is the function of the open spaces created by graft patterns such as mesh and strip grafts?
For how long should wound drains left in place?
Why might a drain be indicated?
Give an example of a situation in which a closed passive drain might be indicated.
What is the main difference between an open and a closed drain?
What is the name of the soft latex open drain commonly used in small animal wound management?
What is a sump Penrose drain?
State the 3 main disadvantages of drains.
Give 2 examples of complications that could occur if a drain is incorrectly placed.
Briefly describe the principles of drain management.
What is the difference between a fistula and a sinus?

Surgical Nursing

Arlo Guthrie — Tue, 21 Apr 2009 08:39:27 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:39:27

An extremely important duty of the veterinary nurse is that of assisting the surgeon in theatre. This chapter covers the nursing techniques that are necessary to be able to fulfil this role effectively, efficiently and safely.

This part of the book focuses on patient care and medical terminology whist the preceding chapter entitled Theatre Practice concentrates on the maintenance of the theatre and equipment involved. Anaesthesia is also a key subject related to surgical nursing. This has its own chapter (Part II - Chapter 3).

If you are studying this guide in the order that the chapters are numbered, you may find that some parts of several of the topics below have been covered elsewhere. References have been stated to enable you to refer back to other relevant information.

The learning objectives of this chapter are:
To be able to clean and dress wounds and prevent patient interference.
To be able to treat abscesses, ulcers and haematomas under veterinary supervision.
To be able to describe specific types of hernia and rupture.
To be able to state common conditions of the eye and ear that may be surgically corrected.
To understand the procedures involved in the surgical correction of common conditions of the alimentary and respiratory tracts and the urinary system.
To recognise the importance of veterinary dentistry and be able to carry out prophylactic procedures.
To understand general terminology used when discussing fracture repair and the procedures involved in external fixation.
To understand the procedures involved in internal fixation.
To understand the procedures involved in the treatment of dislocations.
To understand the terms and definitions associated with neoplasia, and recognise the importance of cancer patient care.

Theatre Practice - Glossary

Arlo Guthrie — Tue, 21 Apr 2009 08:38:22 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:38:22

Anastomosis = In surgery, any artificial connection of two hollow structures.

Antisepsis = The prevention of infection by destruction or inhibition of micro-organisms using an agent that is effective and safe to use on living tissue.

Asepsis = The complete exclusion of all micro-organisms and spores.

Aseptic technique = The steps taken to prevent contact with and subsequent contamination by micro-organisms.

ASIF = The Association for the Study of Internal Fixation.

Atraumatic needle = A needle pre-packed with attached suture material; the lack of an eye allows suturing with the minimum of tissue drag; also known as a swaged needle.

Autoclave = A steam heated steriliser in which the temperature is raised by increasing the pressure inside and then injecting steam under pressure to provide sufficient moist heat for effective sterilisation.

Cold sterilisation = The use of chemical agents to sterilise surgical instruments (not the most effective method).

DCP's = Dynamic compression plates; used to provide compression across fracture gaps in internal fracture fixation.

Depth gauge = An orthopaedic instrument used to measure the length of screw required for fixation.

Diathermy = Production of heat in a body tissue by a high frequency electrical current; used to coagulate blood vessels or dissect tissues (also known as cautery).

Disinfection = The removal and destruction of micro-organisms from inanimate objects (but not necessarily bacterial spores).

Endogenous = Produced within the organism.

Ethylene oxide = A sporicidal, viricidal gas used for sterilisation of surgical instruments and equipment.

Excision arthroplasty = A surgical technique involving the excision of the joint surfaces affected to enable the gap thus formed to fill with fibrous tissue or muscle.

Exogenous = Of external origin.

Fenestration = A window-like opening; a fenestrated drape is one with an opening to allow surgical access.

Gloving = The adornment of sterile surgical gloves (there are 3 methods; open, closed and plunge).

Gowning = The adornment of a sterile surgical gown.

Haemostats = Artery forceps.

Lachrymal cannula = A cannula used for the flushing of the tear ducts.

Nosocomial infection = A hospital-acquired infection (especially E. Coli and Staphylococcus).

Osteome = A surgical instrument used for the cutting and shaping of bone.

Pathogens = Disease causing micro-organisms.

Retractors = A surgical instrument used to draw apart the edges of a wound to improve accessibility.

Ronguers = A surgical instrument used for nibbling away at bone.

Scrubbing up = The thorough cleansing of the hands and arms to remove as many micro-organisms as possible prior to surgery.

Self-tapping = Describes orthopaedic screws that do not require a pre-bored hole.

Sepsis = Infection.

Septicaemia = The presence of bacteria and large number of their toxins in the blood.

Seroma = An accumulation of fluid under the skin usually following surgery or an injury.

Sterilisation = The destruction of all micro-organisms and spores.

Tendon transfer = A surgical technique employed to repair ruptured cruciate ligaments.

Thermocouples = Heat sensitive electrical probes used to establish the efficiency of an autoclave.

Trephine = A surgical instrument used for boring holes into the skull.

Thumb forceps = Dressing forceps.

Virulence = The power of a micro-organism to produce toxins or poisons.

Theatre Practice - Summary And Further Reading

Arlo Guthrie — Tue, 21 Apr 2009 08:37:37 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:37:37

A well-run theatre is essential to provide the very best care possible for your patients. It is the role of the veterinary nurse to be responsible for hygiene and organisation in the theatre and related areas. When working in the theatre, remember to be vigilant, clean and tidy and above all use your common sense. As with all subjects, be sure to ask advice if there is an area or aspect where further guidance is required.

Theatre practice is closely linked to surgical nursing, and it is therefore recommended that these subjects be covered together. In addition, the anaesthesia chapter contains further advice regarding post-operative patient care.

Theatre Practice - Case Study

Arlo Guthrie — Tue, 21 Apr 2009 08:36:57 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:36:57

DOG CASTRATION "BREW" COOK - WEIMERANER - MALE - AGE 5 YRS
Brew is a silver Weimeraner, male, age five years. He was admitted for elective castration following recent episodes of overtly sexual behaviour and dominance. It was suggested by the veterinary surgeon that neutering could help to solve these behavioural problems by eliminating the release of the male sex hormone testosterone.

Testosterone is produced by the interstitial cells of the testis (cells of Leydig) and is responsible for sperm production and the development and maintenance of male secondary sexual characteristics.

Beneficial results that may result from castration include reduction of excessive libido and reduction of aggression. It was hoped that the surgery, combined with a retraining program would make Brew an easier dog for his owner to handle.

Bilateral orchidectomy was performed under general anaesthesia. Surgery was unremarkable and no complications such as haemorrhage were evident. Post- operatively, Brew regained his reflexes and appeared to begin to make a normal recovery. He was placed in the recovery room for monitoring for half an hour and then returned to his kennel having made a satisfactory recuperation.

It was noted that Brew was very vocal upon his return to the kennel. Excessive vocalisation may indicate pain. However, 2.6mls of an analgesic drug (Rimadyl) had already been administered pre-operatively. The veterinary surgeon was consulted and advised that further pain relief should not be necessary.

I examined Brew closely, as I was concerned that he had remained in lateral recumbency and had made no attempt to move. He was visibly breathing, but I checked to ensure that the airway was clear prior to undertaking any further investigations. It was possible that Brew was suffering from hypovolaemic shock following internal bleeding. I noted a substantial amount of capillary haemorrhage at the operating site and immediately applied a cool compress to stem the blood flow.

Brew's temperature was then taken and recorded as 38°C which is in the normal range for dogs recovering from general anaesthesia (although slightly lower than the range considered normal in fully conscious adult dogs, ie. 38.3 - 38.7°C). I also checked his extremities and found these to be of a normal temperature.

I then checked Brew's mucous membrane colour and capillary refill time which were both normal. His tongue and gums were pink, and his CRT less than 2 seconds. It was impossible to accurately assess Brew's respiratory rate and listen to his heart due to the constant vocalising and subsequent chest movements. His pulse, however, was strong, regular and within the normal range at 68 beats per minute. These details were duly recorded on the in-patient records.

Finally, I assessed Brew's hydration level by tenting his skin. This sprung back easily indicating that he was not suffering from dehydration. Following my assessment, I was happy that Brew was not in surgical shock. The compress had stopped the haemorrhage by vasoconstriction and was removed. I then ensured that the heat pad was warm and that adequate blankets were provided before enlisting the assistance of a veterinary nurse to help clean the wound.

Sterile saline was warmed to body temperature and used with swabs to gently remove the bloodstains. Caution was exercised in order to prevent disturbance of the clot which had formed at the area. The incision wound was then carefully dried and covered with a sterile, absorbent, non-adhesive dressing which was regularly checked throughout the rest of the day. I was anxious to prevent excessive movement or patient interference, either of which could have caused further haemorrhage. Brew was checked every 5 minutes for the next half hour, and then every half an hour until he was considered well enough to be discharged. No further haemorrhage occurred.

Prior to discharge, Brew's dressing was removed in order to check for haemorrhage and/or loose sutures. The surgical wound was found to be clean and dry. An Elizabethan collar was fitted in order to prevent the patient from licking at the scrotal sack and making himself sore. A dressing was not deemed practical at this site since it would have been likely to become soiled during defecation.

The owner was advised that some bleeding had occurred following the surgery. It was strongly recommended that strict rest be enforced and a very close eye kept on the surgical site. The veterinary surgeon advised re-examination after 3 days in order to check Brew's wound and general demeanour.

Post-Operative Patient Care - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:36:00 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:36:00

ANSWERS

List criteria essential for the recovery room.
- Warm ambient environment.
- Good ventilation.
- Equipment readily available to deal with post-operative emergencies.
What vital signs would you monitor when a patient is recovering from surgery under general anaesthesia?
- Temperature.
- CRT.
- Pulse rate, rhythm and depth.
- Respiratory rate and depth.
- Hydration status.
- Mucous membrane colour.
List 10 possible causes of heat loss.
- Low ambient temperature/draughty environment.
- Damp skin as a result of an overly wet pre-op scrub procedure/strike through.
- Evaporation of moisture from the respiratory tract.
- Evaporation from externalisation of tissues and internal organs.
- General anaesthesia (particularly the use of non-rebreathing circuits).
- Inactivity or a lowered metabolic rate.
- The clipping of hair.
- Large ratio of body surface area to weight.
- Malnutrition.
- Disease/shock.
List 5 signs of hypothermia.
- Shivering.
- Cold extremities.
- Pallid mucous membranes.
- Reduced pulse rate.
- Subnormal core temperature.
State 3 reasons why a drain might be placed following surgery.
- Prophylaxis - to allow drainage from the dead space within the wound.
- Therapeutic drainage of a contaminated wound.
- To remove fluid or air from body cavities such as the chest.
State the 2 types of closed drain and briefly describe each.
- Active - a suction device is employed.
- Passive - a simple collection bag is employed which relies upon drainage by gravity.
From what material are Penrose drains made?
Soft latex rubber.
What is a sump Penrose drain?
A Foley catheter is placed inside a fenestrated Penrose drain. This enables fluid to pass via the outside of the Foley (sump) drain. The Penrose drain prevents the adhesion of tissue to the Foley drain. These drains are therefore suitable for long-term use.

Post-Operative Patient Care

Arlo Guthrie — Tue, 21 Apr 2009 08:35:22 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:35:22

QUESTIONS

List criteria essential for the recovery room.
What vital signs would you monitor when a patient is recovering from surgery under general anaesthesia?
List 10 possible causes of heat loss.
List 5 signs of hypothermia.
State 3 reasons why a drain might be placed following surgery.
State the 2 types of closed drain and briefly describe each.
From what material are Penrose drains made?
What is a sump Penrose drain?

Patient Care Pre & During Surgery - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:33:52 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:33:52

ANSWERS

List the duties of the veterinary nurse upon admission of a patient for surgery.
- Ensure that a consent form has been signed and that all details are correct. (Ensure that you have a contact telephone number).
- Check the reason for admission.
- Where necessary, identify the surgical site.
- Explain the procedure to the owner.
- Ensure that the patient is in good health for routine operations such as neutering or that the symptoms have not worsened since the animal was last seen by the veterinary surgeon.
- Weigh the patient.
- Fit an identity tag and label any items brought in with the patient such as collars, leads, baskets, bowls etc.
- Ensure that preoperative instructions have been carried out (eg. fasting prior to anaesthesia).
- Ensure that all relevant medical history is collated (radiographs, blood test reports etc).
- Bathe the patient if feasible to reduce contamination risk. This is especially important in elective orthopaedic procedures).
Name 3 common types of skin bacteria.
- Staphylococcus.
- Bacillus.
- Streptococcus.
When clipping around a wound, what can be used to prevent hair entering the wound?
K-Y jelly.
List 4 considerations to take into account when clipping up an area prior to surgery.
- Ensure that the clipper blades are clean and sharp prior to use.
- Ensure that the area is large enough and in the correct position for the surgeon.
- Clip neatly.
- Clip carefully to prevent skin excoriation.
How can small loose hairs be removed?
With a vacuum cleaner.
What is the main advantage of clipping whilst the animal is under general anaesthetic?
This is kinder to the patient if the area is sore; therefore less time is required and restraint is not necessary.
State 2 disadvantages of clipping whilst the patient is under anaesthetic.
- Anaesthesia time is prolonged.
- Decreased asepsis.
List equipment necessary for the cleaning of clippers.
- Damp cloth impregnated with a disinfectant solution (for the handle).
- Small bristle brush (to dislodge hairs from the blades).
- Clipper spray (for disinfection of the blades and the dislodging of hair).
- Disinfectant solution in which to soak the blades after use (prolonged soaking may cause bluntness).
Name 2 surgical scrub solutions that are ideal for surgical site preparation.
- Chlorhexidine (Hibiscrub).
- Povidone iodine (Pevidine).
What is the name of the forceps used by the scrubbed surgical team to carry out the final stage of skin preparation prior to surgery?
Rampley sponge-holding forceps.
What is meant by "strike through"?
This occurs when the skin of a patient has been made overly wet during preparation of the surgical site. The moisture seeps through the linen drapes and becomes cold, thus putting the patient at risk from hypothermia, and wet drapes encourage movement of skin bacteria onto and through the drapes.
When draping a surgical site, which should be the first drape to be positioned?
The drape between the veterinary surgeon and the patient.
What is meant by "sub-draping"?
The use of additional towels or drapes to prevent the incision site from contamination. These are applied to each side of the incision and secured with towel clips.
What is the name given to a drape that possesses a window for the surgical site?
A fenestrated drape.
Why should chlorhexidine not be used in or around the eye?
This has been found to be irritant to the surface of the cornea. Instead, a dilute solution of povidone-iodine should be used. NB. Never use alcohol based solutions.
When should premedicant drugs be administered?
15-60 Minutes prior to anaesthetic induction.
What is the name of the type of suture used to close the anus and thus prevent faecal contamination during surgery?
Purse string suture.
Under what circumstances might the use of an Esmarch bandage and tourniquet be employed?
To provide a bloodless operating field during distal limb surgery.
When might the use of a throat pack be indicated?
During oral or nasal surgery to prevent the aspiration of blood, mucus or calculus.
State possible reasons for postponing surgery.
- Awaiting results of preoperative diagnostic tests such as blood tests and radiographs - it may be prudent to wait as the results may influence the anaesthetic risk.
- Dehydration - if the animal is seriously dehydrated, it may be prudent to administer fluid therapy to rectify this and restore the electrolyte balance beforehand.
- The presence of other injuries.
- To allow reduction of swelling.
- Stabilisation of conditions such as Diabetes Mellitus and Cushings disease.

Patient Care Pre & During Surgery

Arlo Guthrie — Tue, 21 Apr 2009 08:32:58 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:32:58

QUESTIONS

List the duties of the veterinary nurse upon admission of a patient for surgery.
Name 3 common types of skin bacteria.
When clipping around a wound, what can be used to prevent hair entering the wound?
List 4 considerations to take into account when clipping up an area prior to surgery.
How can small loose hairs be removed?
What is the main advantage of clipping whilst the animal is under general anaesthetic?
State 2 disadvantages of clipping whilst the patient is under anaesthetic.
List equipment necessary for the cleaning of clippers.
Name 2 surgical scrub solutions that are ideal for surgical site preparation.
What is the name of the forceps used by the scrubbed surgical team to carry out the final stage of skin preparation prior to surgery?
What is meant by "strike through"?
When draping a surgical site, which should be the first drape to be positioned?
What is meant by "sub-draping"?
What is the name given to a drape that possesses a window for the surgical site?
Why should chlorhexidine not be used in or around the eye?
When should premedicant drugs be administered?
What is the name of the type of suture used to close the anus and thus prevent faecal contamination during surgery?
Under what circumstances might the use of an Esmarch bandage and tourniquet be employed?
When might the use of a throat pack be indicated?
State possible reasons for postponing surgery.

Sutures, Needles & Materials - Answers

Arlo Guthrie — Tue, 21 Apr 2009 08:31:42 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:31:42

ANSWERS

Note: Those questions marked with an asterisk are not essential for NVQ level 3, but may be useful for further study or Diploma candidates.

List 5 ways in which suture materials are categorised.
- Absorbable or non-absorbable.
- Natural or manmade.
- Braided or monofilament.
- Coated or plain.
- Swaged needle or with no attached needle.
List 4 examples of absorbable suture materials.
- Catgut.
- Polydioxanone (PDS).
- Polyglactin 910 (Vicryl).
- Polyglyconate (Maxon).
- Polyglycolic acid (Dexon).
Of your answers to Q1, which is the odd one out and why?
Catgut, because it is a natural product; the rest are all manmade. Catgut is also significant since it almost always provokes an allergic response (usually very minor, but can cause irritation, inflammation and seroma formation).
Chromic catgut has been treated with chromium salts. Why?
In order to slow down the rate of breakdown in the body, and therefore improve strength of suture.
In addition to catgut, can you name 2 other natural suture materials?
- Linen.
- Silk.
List 4 examples of non-absorbable suture materials.
- Polyamide (Ethilon).
- Polybutylester (Novafil).
- Polypropylene (Prolene).
- Silk.
List 3 examples of coated suture materials.
- Chromic catgut.
- Ethibond.
- Vicryl.
List 3 examples of braided suture materials.
- Dexon.
- Stainless steel.
- Vicryl.
List 4 examples of monofilament suture materials.
- Catgut.
- Nylomide/Supramid.
- PDS.
- Prolene.
How are suture materials usually sterilised?
By gamma irradiation or ethylene oxide.
Can you list 4 factors to be taken into account when choosing a suture material?
- Capillarity.
- Knot strength/security.
- Tensile strength.
- Tissue drag.
- Cost.
- Tissue reaction.
For what purpose might you use staples, monofilament nylon or polypropylene?
The closing of the skin (external).
For what purpose might you use polydioxanone, polyglactin 910 or polyglycolic acid?
Suturing of the subcutis.
Suggest a material suitable for suturing the bladder.
Polydioxanone (PDS).
Suggest a material suitable for suturing muscle.
PDS.
* Suggest 4 suitable uses for polypropylene (Prolene).
- Suturing of a hollow viscus.
- The suturing of tendons.
- The suturing of blood vessels.
- The suturing of nerves.
How are suture needles classified?
- By type - eg. round bodied, conventional cutting, reverse cutting.
- By shape - eg. straight, ¼ circle, 3/8 circle, 5/8 circle, half curved, J needle, compound curve.
List 3 factors that determine the strength of a suture needle.
- Diameter of the wire from which the needle is manufactured.
- Cross-sectional shape.
- Type of wire from which the needle is manufactured.
Why should bent suture needles be discarded rather than attempts made to straighten them?
Needles bend when a force is applied which is greater than that for which the needle has been designed. Once this critical point has been reached, the needle is weakened and therefore should not be used.
List important factors concerned with the use of needle holders.
- Carefully select a needle holder to match the size and strength of the needle to be used.
- Never use a needle holder larger than necessary since this can result in damage to the needle and in particular distortion of the curvature.
- Never use needle holders with worn jaws since this can result in needle rotation and instability, as well as damage and loss of strength.
- Never apply excessive force when gripping the needle.
* Suggest a suitable type and size of needle for the suturing of an intestinal incision in a rabbit.
A round bodied needle - size 16.
Describe a reverse cutting needle.
This needle has its cutting edge on the outside of its curvature in order to improve its strength and resistance to bending.
What is the most likely cause of the bending of a needle?
The use of too smaller needle for a given tissue bite.
What is the main advantage of a tapercut needle?
This combines the initial penetration of a cutting needle with the minimised trauma of a round bodied needle.
* When might the use of a trocar point needle be indicated?
When powerful penetration of deep, dense tissue is required.
* When might the use of a micropoint needle be indicated?
Ophthalmic surgery.
Why is it that a needle should be as close as possible in diameter to that of the suture?
Large needle tracts invite bacteria and foreign substances to enter the wound, thus delaying healing.
Name the suture pattern most likely to lead to complete wound breakdown.
Simple continuous.
When might the use of simple interrupted sutures be indicated?
As a buried suture when the suture ends should be cut short.
For skin closure.
When might the use of simple continuous sutures be indicated?
The closure of subcutaneous tissues.
For skin closure.
What suture patterns are ideal for the closure of skin wounds under moderate tension?
Horizontal or vertical mattress.
What is another name for a swaged needle?
Atraumatic.
After what period are non-absorbable skin sutures usually removed?
Usually anything from 7-21 days depending upon the type of wound.
You are asked to remove the sutures from a bitch 10 days following ovariohysterectomy. The wound appears closed, but is quite red and sore as a result of her licking. What would you recommend?
- Assess vital signs including hydration status and CRT to rule out internal haemorrhage.
- Remove alternate sutures in case of wound breakdown and re-examine the bitch in 3-5 days to reassess.
- Prevent further patient interference by providing an Elizabethan collar.
- Advise salt-water bathing twice daily to ensure that the wound is kept clean.
Give 3 alternatives to sutures.
- Staples.
- Tissue glue.
- Adhesive tapes.

Sutures, Needles & Materials

Arlo Guthrie — Tue, 21 Apr 2009 08:30:41 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:30:41

QUESTIONS

Note: Those questions marked with an asterisk are not essential for NVQ level 3, but may be useful for further study or Diploma candidates.

List 5 ways in which suture materials are categorised.
List 4 examples of absorbable suture materials.
Of your answers to Q1, which is the odd one out and why?
Chromic catgut has been treated with chromium salts. Why?
In addition to catgut, can you name 2 other natural suture materials?
List 4 examples of non-absorbable suture materials.
List 3 examples of coated suture materials.
List 3 examples of braided suture materials.
List 4 examples of monofilament suture materials.
How are suture materials usually sterilised?
Can you list 4 factors to be taken into account when choosing a suture material?
For what purpose might you use staples, monofilament nylon or polypropylene?
For what purpose might you use polydioxanone, polyglactin 910 or polyglycolic acid?
Suggest a material suitable for suturing the bladder.
Suggest a material suitable for suturing muscle.
* Suggest 4 suitable uses for polypropylene (Prolene).
How are suture needles classified?
List 3 factors that determine the strength of a suture needle.
Why should bent suture needles be discarded rather than attempts made to straighten them?
List important factors concerned with the use of needle holders.
* Suggest a suitable type and size of needle for the suturing of an intestinal incision in a rabbit.
Describe a reverse cutting needle.
What is the most likely cause of the bending of a needle?
What is the main advantage of a tapercut needle?
* When might the use of a trocar point needle be indicated?
* When might the use of a micropoint needle be indicated?
Why is it that a needle should be as close as possible in diameter to that of the suture?
Name the suture pattern most likely to lead to complete wound breakdown.
When might the use of simple interrupted sutures be indicated?
When might the use of simple continuous sutures be indicated?
What suture patterns are ideal for the closure of skin wounds under moderate tension?
What is another name for a swaged needle?
After what period are non-absorbable skin sutures usually removed?
You are asked to remove the sutures from a bitch 10 days following ovariohysterectomy. The wound appears closed, but is quite red and sore as a result of her licking. What would you recommend?
Give 3 alternatives to sutures.

Care & Handling Of Surgical Instruments - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 08:28:38 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 09:28:38

Ensure that you remove any jewellery and wear a protective apron and gloves. Some people may be sensitive to the detergent contained within instrument cleaning products and it is therefore sensible to protect yourself.
New instruments are frequently coated in a fine layer of metallic dust and lubricant, and should therefore be washed and dried thoroughly prior to sterilisation.
Always rinse instruments as soon as possible in order to remove blood, serous fluid and saline. It is easier to remove fresh dirt than ingrained dirt and more hygienic. Use tepid water rather than very hot or very cold water.
When cleaning surgical instruments, never use caustic cleaners or any other cleaner other than those specified as suitable for the cleaning of surgical instruments. Avoid detergents with a high pH as these may cause damage.
When hand cleaning instruments, use a soft brush and never steel wool or any other abrasive method.
Cold sterilising solutions are not ideal, but if their use is indicated bear in mind that prolonged soaking may cause corrosion. Always change the solution regularly and use according to the manufacturer's instructions.
Always thoroughly dry instruments following washing since moisture may cause corrosion.
When autoclaving, use distilled or demineralised water since iron, sodium, calcium, magnesium or copper in the water may cause spotting, staining or corrosion. Traces of chlorine bleach may also cause staining or corrosion during autoclaving.
Autoclave stainless steel instruments separately to chrome plated instruments since any break in the surface of the chrome plate will allow an electrolytic action to develop between the dissimilar metals causing pitting and/or a rusty appearance.
Following sterilisation, do not open the autoclave too quickly otherwise excessive condensation will develop on the surface of the instruments.

Laying Out An Instrument Trolley - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 07:54:29 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:54:29

This task may have 2 stages:

Remove a sterile drape from a drum and place on the instrument trolley in a sterile manner.
Lay out a selection of instruments.

The first task is pretty straightforward and requires practice rather than a list of instructions here. Just a few pointers to remember:

Make a point of checking that the holes in the autoclaving drum are closed and that the sterilisation date is acceptable.
Ensure that the surface of the instrument trolley is clean and dry. If disinfectant and surgical spirit are available - use them!
The forceps used to handle the drape are called Cheatles and it is usual to use 2 pairs when handling drapes.
Remember that the drape is sterile - and if you do accidentally touch it, you would discard that drape and use
a fresh one.

The second part of the task usually involves the identification of some surgical instruments.

Surgical Instruments - Answers

Arlo Guthrie — Tue, 21 Apr 2009 07:30:50 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:30:50

ANSWERS

Note: Those questions marked with an asterisk are not essential for NVQ level 3, but may be useful for further study or Diploma candidates.

Name and briefly describe one type of towel clip.
- Backhaus - a racked towel clip for secure, accurate fixation.
- Mayo - as Backhaus but larger.
- Jones - a cross action towel clip.
What sized blades fit a number 3 scalpel handle?
8-15.
What sized blades fit a number 4 scalpel handle?
20-25.
A number 9 scalpel handle takes blades 8-15, but how does it differ to a number 3 handle?
It is finer and subsequently lighter.
* What is a Bard-Parker?
A type of scalpel handle.
Name 4 different types of needle holder.
- Bruce-Clarke.
- Fosters.
- Gillies.
- Kilner.
- Lawson Tait.
- Mayo-Hegar.
- McPhail.
- Olson-Hegar.
What are Rampley's sponge holding forceps designed for?
Holding swabs for preparation of the surgical site with skin disinfectant.
What are the forceps called that are used to lay out an instrument trolley in a sterile fashion?
Cheatles.
What is another name for artery forceps?
Haemostats.
What 2 factors must be checked prior to the use of haemostats?
- Alignment.
- Ratchet mechanism.
Name 3 types of haemostat.
- Cairns.
- Crile.
- Halstead mosquito.
- Kelly.
- Rochester Pean.
- Spencer Wells.
Which of your answers to Q11 would you select as ideal for all fine surgery?
Halstead mosquito.
Which of your answers to Q11 would you select as the ideal forcep for clamping large vessels and organs?
Rochester Pean.
What are Mayo scissors generally used for?
The cutting of dense tissue.
What are Metzenbaum scissors generally used for?
The cutting and dissecting of delicate tissue.
* What is the name of the angled scissors used for cardio-vascular work?
Potts scissors.
What are Lister scissors designed for?
The safe cutting of bandages and casts.
What are Bohler's scissors designed for?
The safe cutting of plaster casts.
What are Heath scissors designed for?
The cutting of sutures.
* What are Aufricht scissors designed for?
Dissection and precise cutting.
* What is the name of the scissors that have all the advantages and familiarity of Mayo scissors but are scaled down for fine surgery (e.g. ocular surgery)?
Strabismus scissors.
Allis, Babcock and Doyen are all types of what?
Tissue forcep.
Allis tissue forceps should not be used on skin or hollow organs. Can you explain why, and suggest a suitable type for clamping the bowel?
Allis tissue forceps are fairly traumatic. The Doyen forceps are specially designed bowel clamps.
What is another name given to thumb forceps?
Dressing forceps.
Name 3 types of thumb forceps.
- Adson.
- Brown-Adson.
- Cooley.
- DeBakey.
- Jeans.
- Semkin.
* Which 2 of your answers to Q17 are atraumatic for cardiovascular work?
- Cooley.
- DeBakey.
What is the purpose of a suction piece?
Removal of blood or other fluid from a surgical field.
Name 1 type of suction piece.
- Frazier Ferguson.
- Poole.
- Yankauer.
Name 1 type of rat-toothed forcep.
- Approximating.
- Bonney.
- Gillies.
- Treves.
- Waugh.
Name 1 type of non-dissecting forcep.
- Debakey.
- Dressing.
- McIndoe.
  
  NB. Adson dissecting forceps are available in both toothed and non-toothed patterns.
* What are Angiotribes?
Extremely strong clamps with interlocking jaws that clamp securely without crushing. They are ideal for use in bitch spays.
State the 2 categories of retractor.
- Hand held.
- Self retaining.
Name 2 types of self retaining retractor.
- Alm.
- Balfour.
- Finochietto.
- Gelpi.
- Gosset.
- Travers.
- Turvier.
- West.
* Which type of self retaining retractor is commonly known as "rib spreaders"?
Finochietto.
Name 2 types of hand held retractor.
- Hohmann.
- Kilner.
- Langenbeck.
- Malleable.
What are Liston and Ruskin cutters designed for?
The cutting of bone.
What is the correct term for "bone nibbling forceps"?
Rongeurs.
* List 3 types of rongeur.
- Kerrison.
- Lempert.
- Stille Luer.
* What is the name of the ronguers specially designed for fine spinal work?
Kerrison.
* Bone holding forceps are used to manipulate and hold fragments of bone in place (with or without ratchets). Can you name 3 types?
- Lowman.
- Reduction.
- Spin (speed) Lock.
Name an instrument used for cutting bone in conjunction with a mallet.
Chisel.
What is the main difference between a chisel and an osteotome?
A chisel has 1 bevelled edge, whilst an osteotome has 2 bevelled edges and a central cutting edge.
* Name 1 type of osteome.
Lambotte.
What is a depth gauge used for?
In orthopaedics; used to determine the length of screw needed to penetrate the bone. The end of the gauge is inserted into the drill hole and hooked over the distal surface. The sleeve is then advanced against the bone plate and the thumb screw is tightened. The gauge is then withdrawn and the quarter inch calibrations on the stem indicate the length of screw required.
What is the name of the instrument used for the extraction of Steinman pins, in open pinning (particularly of the femur)?
Bone pin grip.
* Name a type of bone pin introducer.
Leighton's.
Name 1 type of bone holding forceps.
- Burn's.
- Fergusson's.
- Hey Grove's.
Name a type of curette.
Volkmann's bone spoon.
During which operation might the veterinary surgeon use a McFarlane's teresector?
Excision arthroplasty of the femoral head.
What instrument is used to shape grooves for tendon transfer (a method used for repairing ruptured cruciate ligaments)?
Putti rasp.
What is Gigli wire used for?
For cutting (used with a pair of Gigli saw handles).
Name 4 types of bone pin and briefly describe each.
- Arthrodesis - very small.
- Kirschner - small with a flattened point.
- Rush - curved.
- Steinman - larger than Kirschner with a trocar point.
What are finger plates?
Small, stainless steel orthopaedic implants suitable for toy breeds such as the Yorkshire terrier.
Sherman and Venables are 2 types of what?
Bone plates.
How would you quickly recognise acetabular plates?
They are curved (used for open reduction of the hip joint).
What are DCP's?
Dynamic compression plates - used for internal fracture fixation. These must be "tapped". The screw holes are oval in shape so that screws inserted concentrically will provide compression across fracture gaps. ASIF screws are required and these can be recognised by their hexagonal pattern screw driver insertion point on the head of the screw.
Why are DCP plates preferable to other bone plate?
They provide active compression of the fracture site.
What does ASIF stand for?
The Association for the Study of Internal Fixation.
* What is a Snellen's vectis used for?
Ophthalmic surgery; manipulation of the lens during extracapsular extraction.
* St Martin's and Barraquer's are examples of what?
Corneal forceps.
* Pooley's and Castroviejo's are examples of what?
Ophthalmic scissors (Pooley's are used for conjunctival cutting, whilst Castroviejo's are used for corneal cutting).
* What is the name of the forcep used to remove residual lens material during extracapsular extraction?
Arruga's intracapsule forceps.
* Name 2 types of lachrymal cannula.
- Harrison Butler.
- Lang.
What is a trephine?
An instrument used to bore holes into the skull. An example is Horsley's trephine.

Surgical Instruments

Arlo Guthrie — Tue, 21 Apr 2009 07:29:30 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:29:30

QUESTIONS

Note: Those questions marked with an asterisk are not essential for NVQ level 3, but may be useful for further study or Diploma candidates.

Name and briefly describe one type of towel clip.
What sized blades fit a number 3 scalpel handle?
What sized blades fit a number 4 scalpel handle?
A number 9 scalpel handle takes blades 8-15, but how does it differ to a number 3 handle?
* What is a Bard-Parker?
Name 4 different types of needle holder.
What are Rampley's sponge holding forceps designed for?
What are the forceps called that are used to lay out an instrument trolley in a sterile fashion?
What is another name for artery forceps?
What 2 factors must be checked prior to the use of haemostats?
Name 3 types of haemostat.
Which of your answers to Q11 would you select as ideal for all fine surgery?
Which of your answers to Q11 would you select as the ideal forcep for clamping large vessels and organs?
What are Mayo scissors generally used for?
What are Metzenbaum scissors generally used for?
* What is the name of the angled scissors used for cardio-vascular work?
What are Lister scissors designed for?
What are Bohler's scissors designed for?
What are Heath scissors designed for?
* What are Aufricht scissors designed for?
* What is the name of the scissors that have all the advantages and familiarity of Mayo scissors but are scaled down for fine surgery (e.g. ocular surgery)?
Allis, Babcock and Doyen are all types of what?
Allis tissue forceps should not be used on skin or hollow organs. Can you explain why, and suggest a suitable type for clamping the bowel?
What is another name given to thumb forceps?
Name 3 types of thumb forceps.
* Which 2 of your answers to Q17 are atraumatic for cardiovascular work?
What is the purpose of a suction piece?
Name 1 type of suction piece.
Name 1 type of rat-toothed forcep.
Name 1 type of non-dissecting forcep.
* What are Angiotribes?
State the 2 categories of retractor.
Name 2 types of self retaining retractor.
* Which type of self retaining retractor is commonly known as "rib spreaders"?
Name 2 types of hand held retractor.
What are Liston and Ruskin cutters designed for?
What is the correct term for "bone nibbling forceps"?
* List 3 types of rongeur.
* What is the name of the ronguers specially designed for fine spinal work?
* Bone holding forceps are used to manipulate and hold fragments of bone in place (with or without ratchets). Can you name 3 types?
Name an instrument used for cutting bone in conjunction with a mallet.
What is the main difference between a chisel and an osteome?
* Name 1 type of osteome.
What is a depth gauge used for?
What is the name of the instrument used for the extraction of Steinman pins, in open pinning (particularly of the femur)?
* Name a type of bone pin introducer.
Name 1 type of bone holding forceps.
Name a type of curette.
During which operation might the veterinary surgeon use a McFarlane's teresector?
What instrument is used to shape grooves for tendon transfer (a method used for repairing ruptured cruciate ligaments)?
What is Gigli wire used for?
Name 4 types of bone pin and briefly describe each.
What are finger plates?
Sherman and Venables are 2 types of what?
How would you quickly recognise acetabular plates?
What are DCP's?
Why are DCP plates preferable to other bone plates?
What does ASIF stand for?
* What is a Snellen's vectis used for?
* St Martin's and Barraquer's are examples of what?
* Pooley's and Castroviejo's are examples of what?
* What is the name of the forcep used to remove residual lens material during extracapsular extraction?
* Name 2 types of lachrymal cannula.
What is a trephine?

Gloving - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 07:24:11 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:24:11

Step 1: Equipment

Equipment is minimal!

1 pair of sterile surgical gloves.
1 sterile gown with sleeves (necessary for the closed gloving method).

Step 2: Method

There are 3 methods - open gloving, closed gloving and plunge gloving. Plunge gloving is not recommended and is therefore not covered here. Closed gloving is the technique of choice since there is minimal risk of contamination

Ensure that you have a clean, flat, dry surface upon which to lay your glove pack.
Remove any jewellery and put on your gown.
Select a suitably sized pair of sterile surgical gloves.

Open gloving method:

Ask an assistant to open the glove pack.
Place the open glove pack so that the fingers are pointing upwards.
Pick up the right glove with the left hand, taking care only to handle the inner surface of the turned down cuff.
Pull the glove onto the right hand, hooking the thumb underneath the cuff as the hand is pushed inside; do not unfold the cuff.
Next pick up the left glove underneath the folded cuff with the gloved fingers of the right hand.
Pull the glove onto the left hand, hooking the rim over the thumb to enable the cuff of the gown to be adjusted.
Pull the cuff of the left glove over the cuff of the gown using the fingers of the right hand.
Pull the cuff of the right glove over the cuff of the gown using the fingers of the left hand.
Stand still with your hands clasped at chest height to avoid contamination.
The outer surface of the glove must not come into contact with the inner surface of the hand at any time.

Closed gloving method:

Ask an assistant to open the glove pack.
Place the open glove pack so that the fingers are pointing downwards. Remember that the right glove will now be on the left, and the left on the right.
Keep your hands inside the cuffs of the gown and pick up the right glove by the rim of the cuff of the glove with the right hand.
Turn the hand over so that the glove lies on the palm surface with the fingers still pointing towards your body.
Pick up the rim with the opposite hand.
Pull the rim over the fingers and over the dorsal surface of the wrist.
Push the hand forwards into the glove.
Now pick up the left glove and repeat the process.
Stand still with your hands clasped at chest height to avoid contamination.

Scrubbing Up - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 07:22:57 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:22:57

Step 1: Equipment

Equipment is minimal for this task.

Scrub sink with water supply (elbow or foot operated).
Plain soap.
Nail pick.
Sterile scrubbing brush/es.
Surgical scrub solution such as chlorhexidine (Hibiscrub) or povidone-iodine (Pevidine).
Sterile hand towel.

Step 2: Method

Remove watch/any jewellery.
Cut nails and remove any nail varnish.
Adjust the water supply (ideally foot operated).
Wash the hands with plain soap.
Clean the nails with a nail pick.
Wash the arms and elbows, keeping the hands higher than the elbows so that water drains down towards the unscrubbed upper arms. The purpose of this stage is to remove organic matter and grease.
Rinse the hands and then the arms.
Wash the hands and arms with a scrub solution (chlorhexidine or povidone-iodine).
Rinse the hands and then the arms.
Take a sterile scubbing brush and scrub the palm, wrist, 4 sides of each finger, thumb and nails of the left hand using surgical scrub (E-Z scrub brushes come with their own scrub solution). Do not scrub the backs of the hands and arms as this may lead to excoriation.
Either rinse the brush or take a new one.
Scrub the palm, wrist, fingers, thumb and nails of the right hand using surgical scrub.
Rinse.
Repeat the procedure of washing the hands and then the arms (but do not include the elbows).
Rinse.
Dry with a sterile hand towel, using a separate quarter for each hand and arm.

IF DONE PROPERLY, THE PROCEDURE SHOULD TAKE BETWEEN 5 & 10 MINUTES.

TAKE CARE NOT TO TOUCH THE TAPS, SINK OR SCRUB DISPENSER - IF SO THE PROCEDURE MUST BE REPEATED.

ONCE THE TASK IS COMPLETE - KEEP HANDS RAISED AT CHEST LEVEL BUT WITHOUT TOUCHING CLOTHING, READY FOR GOWNING AND/OR GLOVING.

Scrubbing Up, Gowning & Gloving - Answers

Arlo Guthrie — Tue, 21 Apr 2009 07:21:29 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:21:29

ANSWERS

What is meant by "scrubbing up"?
The systematic scrubbing of the hands, arms and elbows performed by each member of the surgical team prior to each operation.
What is the aim of the scrubbing up routine?
To destroy as many micro-organisms as possible from the surface of the arms and hands since it is not possible to sterilise the skin.
List 3 agents commonly used for scrubbing up.
- Chlorhexidine.
- Povidone-iodine.
- Triclosan.
List 8 properties possessed by an ideal surgical scrub solution.
- Effective against a wide range of micro-organisms.
- Long residual effect.
- Active and effective in the presence of organic matter.
- Quick acting.
- Quick to apply.
- Non-irritant.
- Economical.
- Suitable for veterinary use.
How long should the scrubbing procedure take?
Between 5 and 10 minutes.
Name the 2 different types of gown.
- Side-tying.
- Back-tying.
Why are surgical gowns folded inside outermost?
This prevents the handling of the outside of the gown with ungloved hands.
Name the 3 methods of putting on surgical gloves.
- Closed gloving.
- Open gloving.
- Plunge method.
Of the 3 methods listed in your answer to Q7, which is the least desirable and why?
The plunge method (the sterile glove is held open by a scrubbed assistant and the hand inserted); there is a risk of contaminating both personnel involved with this technique which is why it is not commonly used.
Of the 3 methods listed in your answer to Q7, which is the least likely to cause contamination of the gloves and why?
The closed gloving method, because your hand stays within the gown and so the risk of your hand accidentally coming
into contact with the outside of the glove is significantly reduced.
Why are starch-free gloves considered better than the powdered variety?
It has been shown that powder may interfere with wound healing.
Once gowned and gloved, how can the wearer reduce the risk of contamination?
- Avoid unnecessary movement.
- Keep the hands up, clasped together against the front of the chest until surgery commences.
- Do not turn with the back to any sterile areas (especially when wearing a back-tying gown).
What might be considered when there is an increased risk of contamination such as for a procedure that involves entry into the intestinal tract?
Double gloving.
What is meant by a nosocomial infection?
A hospital-acquired infection (especially Escheria coli and Staphylococcus).

Scrubbing Up, Gowning & Gloving

Arlo Guthrie — Tue, 21 Apr 2009 07:20:21 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:20:21

QUESTIONS

What is meant by "scrubbing up"?
What is the aim of the scrubbing up routine?
List 3 agents commonly used for scrubbing up.
List 8 properties possessed by an ideal surgical scrub solution.
How long should the scrubbing procedure take?
Name the 2 different types of gown.
Why are surgical gowns folded inside outermost?
Name the 3 methods of putting on surgical gloves.
Of the 3 methods listed in your answer to Q7, which is the least desirable and why?
Of the 3 methods listed in your answer to Q7, which is the least likely to cause contamination of the gloves and why?
Why are starch-free gloves considered better than the powdered variety?
Once gowned and gloved, how can the wearer reduce the risk of contamination?
What might be considered when there is an increased risk of contamination such as for a procedure that involves entry into the intestinal tract?
What is meant by a nosocomial infection?

The Operating Theatre - Answers

Arlo Guthrie — Tue, 21 Apr 2009 07:18:00 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:18:00

ANSWERS

List the items of theatre clothing that should be worn by all theatre personnel.
- Caps.
- Masks.
- Scrub suits.
- Antistatic footwear.
In addition to the items listed in Q1, what additional attire should be worn by the surgical team?
- Sterile gowns.
- Sterile gloves.
Why is a well-ventilated theatre essential?
Hot, humid conditions encourage the growth of pathogens (especially Pseudomonas spp.) and pose a great threat to asepsis.
In addition to the operating theatre itself, list the other areas which comprise the theatre suite.
- Patient preparation area (for induction of anaesthesia, catheterisation, clipping and surgical site preparation).
- Changing room for theatre personnel.
- Recovery room (a warm, quiet area fully equipped for dealing with post-operative emergencies).
- Surgeons' scrub up area.
- Sterile storage area.
- Washing & sterilising room.
List 10 essential properties of the theatre.
- Must be a closed, clean environment that is an end room rather than a thoroughfare.
- Good lighting.
- Well ventilated.
- Ambient temperature of 15-20°C.
- Scavenge system for anaesthetic waste gas.
- Adjustable operating table.
- Power supply (in waterproof casing).
- Easily cleaned, hard-wearing, non-slip floors.
- Easily cleaned walls painted in a light colour with impervious paint.
- Minimal shelving and furniture (to avoid dust accumulation).
List desirable features of the theatre.
- X-ray viewer.
- Air supply for power tools.
- Wall clock.
- Dry wipe board.
- Double swing doors.
- Frosted glass windows (these should be kept closed).
- Coved corners and edges of walls to facilitate cleaning.
Every practice will have its own set of local rules drawn up with regard to theatre procedures. Can you name some common sense rules that will be similar across the board?
- No admittance by unauthorised personnel. Personnel in the theatre to be kept to a minimum (the greater the number of people, the greater the risk of infection).
- Ensure that all equipment is regularly serviced and a maintenance record kept.
- The correct attire to be worn at all times.
- No eating, drinking or smoking.
- Use a new set of sterile instruments for each surgical procedure.
- Maintain a strict cleaning protocol.
- Plan the surgical list to ensure that clean procedures are carried out first and contaminated surgery last.
- The surgical team must not touch any non-sterile surfaces during surgery.
- Ensure that any contaminated instruments or equipment are not returned to the sterile trolley.
- Keep a record book of all surgical procedures so that if any sepsis problems should arise, the cause can be detected.
List 6 hazards that may pose a risk to theatre personnel.
- Pollution from anaesthetic gases.
- Sharps (needles, blades and stylets).
- Clinical waste.
- Pathological material.
- Chemicals.
- Drugs.
Briefly outline the duties of the scrubbed nurse.
- Prepare the instrument trolley.
- Assist in draping the patient.
- Pass sterile instruments, swabs and equipment to the veterinary surgeon as necessary.
- Assist with surgery as necessary.
- Take responsibility for all instruments and equipment used during surgery.
- Carrying out a swab and instrument count prior to closure of the wound.
Briefly outline the duties of the circulating nurse.
- Help to prepare the theatre, equipment and instruments ready for surgery.
- Tie the surgical team into their gowns.
- Position the patient on the operating table.
- Prepare the surgical site.
- Connect apparatus (eg. diathermy).
- Open the sterile packs.
- Count swabs, sutures and needles (with the scrubbed nurse).
- Assist with anaesthesia.
- Prepare post-operative dressings.
- Assist with the cleaning of the theatre.

Prepare For Autoclaving - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 07:15:30 GMT

Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:15:30

Prepare For Autoclaving - Practical Task

This task will depend largely on the type of item/s that you are asked to sterilise, and the method of sterilisation.

Step 1: Equipment

First select and lay out all the equipment required.

Item/s to be sterilised (this could be a single instrument, selection of instruments, drape/s or gown).
Suitable packaging material/s.
Method of indication of sterilising efficiency.
Waterproof marker for labelling.
Scissors for cutting tape/nylon film if used.
Tape roller for removing hair/fluff from linen drapes/gowns.
Swabs/tape/plastic protectors to prevent sharp items from penetrating soft packaging materials.
Protective gloves and apron if chemical sterilisation solutions are to be used.

Step 2: Procedure

1. Collect together the equipment as specified in Step 1.

2. Instruments

Ensure instruments are clean, dry and free from grease and blood (grease and protein material will prevent the effective penetration of steam if an autoclave is to be used).
Protect any sharp points from penetrating soft packaging by utilising swabs and tape, needle caps or proprietary plastic protectors.

Select packaging material - see table below.

Method of sterilisation	Nylon film	Seal & Peel	Linen wrap with outer paper layer	Drum	Box or carton
Autoclave			Must have a drying cycle	not for single instruments
Oven
Chemical
Ethylene oxide

Select a suitable indicator of sterilisation - see table below.
Be careful to select the best type for the chosen sterilisation method. Remember that Browne's tubes are available to indicate changes at several different changes, and that different types of chemical strip are for use in the autoclave to those designed for use with ethylene oxide.

Method of sterilisation	Bowie Dick tape	Spore test strips	Browne's tubes	Chemical strips
Autoclave	Beige to brown			Best method
Oven
Chemical
Ethylene oxide	Yellow to red

Carefully package up your instruments; if using chemical strips - these should be placed within the packaging. Bowie Dick tape is usually used to seal up packages or a strip can be placed on the outer of the sterilising container. Browne's tubes are placed within the autoclave or oven itself, whilst spore test strips may be placed within the autoclave, oven or ethylene oxide sterilising unit.
Check the package for any sign of damage.
Label clearly with waterproof marker the date of sterilisation, contents of the package (EG cat spay kit) and your initials.
NB. If ethylene oxide is used, don't forget to place the gas ampoule within the polythene liner bag and seal with a metal tie.

3. Gowns & Drapes

Select the appropriate gown/drapes.
Ensure that you have a clean, flat and dry surface upon which to work.
Lay out the gown or drape and inspect for any evidence of dirt. If blood is found, the item should be scrubbed thoroughly in tepid water and relaundered since protein based stains will decrease the efficiency of sterilisation.
Remove any animal hairs or fluff with a tape roller.
Carefully fold the item:
i) Gowns - with the gown lying on the table with the inside surface facing down, lay flat, ensure arm and ties are folded onto the gown, fold in half lengthways, and again in half lengthways, then fold the top and bottom edges to the middle, then fold in half (the gown is then ready to be picked up by the inside of the collar).
ii) Drapes - lay out flat, concertina widthways and then lengthways.
Select suitable packing material appropriate for the type of sterilisation employed.
Select a suitable method of sterilisation indication appropriate for the type of sterilisation employed.
Carefully package up your gown/drapes.
Check the package for any sign of damage.
Label clearly with waterproof marker the date of sterilisation, contents of the package (eg. cat spay kit) and your initials.

Prepare For Autoclaving - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 07:11:51 GMT

Revision 2 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:11:51

Prepare For Autoclaving - Practical Task

INTRODUCTION

This task will depend largely on the type of item/s that you are asked to sterilise, and the method of sterilisation.

Step 1: Equipment

First select and lay out all the equipment required.

Item/s to be sterilised (this could be a single instrument, selection of instruments, drape/s or gown).

Suitable packaging material/s.

Method of indication of sterilising efficiency.

Waterproof marker for labelling.

Scissors for cutting tape/nylon film if used.

Tape roller for removing hair/fluff from linen drapes/gowns.

Swabs/tape/plastic protectors to prevent sharp items from penetrating soft packaging materials.

Protective gloves and apron if chemical sterilisation solutions are to be used.

Step 2: Procedure

1. Collect together the equipment as specified in Step 1.

2. Instruments

Ensure instruments are clean, dry and free from grease and blood (grease and protein material will prevent the effective penetration of steam if an autoclave is to be used).

Protect any sharp points from penetrating soft packaging by utilising swabs and tape, needle caps or proprietary plastic protectors.

Select packaging material - see table below.

Method of sterilisation

Nylon film

Seal & Peel

Linen wrap with outer paper layer

Drum

Box or carton

Autoclave

Must have a drying cycle

not for single instruments

Oven

Chemical

Ethylene oxide

Select a suitable indicator of sterilisation - see table below.
Be careful to select the best type for the chosen sterilisation method. Remember that Browne's tubes are available to indicate changes at several different changes, and that different types of chemical strip are for use in the autoclave to those designed for use with ethylene oxide.

Method of sterilisation

Bowie Dick tape

Spore test strips

Browne's tubes

Chemical strips

Autoclave

Beige to brown

Best method

Oven

Chemical

Ethylene oxide

Yellow to red

Carefully package up your instruments; if using chemical strips - these should be placed within the packaging. Bowie Dick tape is usually used to seal up packages or a strip can be placed on the outer of the sterilising container. Browne's tubes are placed within the autoclave or oven itself, whilst spore test strips may be placed within the autoclave, oven or ethylene oxide sterilising unit.

Check the package for any sign of damage.

Label clearly with waterproof marker the date of sterilisation, contents of the package (EG cat spay kit) and your initials.

NB. If ethylene oxide is used, don't forget to place the gas ampoule within the polythene liner bag and seal with a metal tie.

3. Gowns & Drapes

Select the appropriate gown/drapes.

Ensure that you have a clean, flat and dry surface upon which to work.

Lay out the gown or drape and inspect for any evidence of dirt. If blood is found, the item should be scrubbed thoroughly in tepid water and relaundered since protein based stains will decrease the efficiency of sterilisation.

Remove any animal hairs or fluff with a tape roller.

Carefully fold the item:

i) Gowns - with the gown lying on the table with the inside surface facing down, lay flat, ensure arm and ties are folded onto the gown, fold in half lengthways, and again in half lengthways, then fold the top and bottom edges to the middle, then fold in half (the gown is then ready to be picked up by the inside of the collar).
ii) Drapes - lay out flat, concertina widthways and then lengthways.
Select suitable packing material appropriate for the type of sterilisation employed.

Select a suitable method of sterilisation indication appropriate for the type of sterilisation employed.

Carefully package up your gown/drapes.

Check the package for any sign of damage.

Label clearly with waterproof marker the date of sterilisation, contents of the package (eg. cat spay kit) and your initials.

Prepare For Autoclaving - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 07:04:05 GMT
Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:04:05

INTRODUCTION

This task will depend largely on the type of item/s that you are asked to sterilise, and the method of sterilisation.

Step 1: Equipment

First select and lay out all the equipment required.

Item/s to be sterilised (this could be a single instrument, selection of instruments, drape/s or gown).

Suitable packaging material/s.

Method of indication of sterilising efficiency.

Waterproof marker for labelling.

Scissors for cutting tape/nylon film if used.

Tape roller for removing hair/fluff from linen drapes/gowns.

Swabs/tape/plastic protectors to prevent sharp items from penetrating soft packaging materials.

Protective gloves and apron if chemical sterilisation solutions are to be used.

Step 2: Procedure

1. Collect together the equipment as specified in Step 1.

2. Instruments

Ensure instruments are clean, dry and free from grease and blood (grease and protein material will prevent the effective penetration of steam if an autoclave is to be used).

Protect any sharp points from penetrating soft packaging by utilising swabs and tape, needle caps or proprietary plastic protectors.

Select packaging material - see table below.

Method of sterilisation

Nylon film

Seal & Peel

Linen wrap with outer paper layer

Drum

Box or carton

Autoclave

Must have a drying cycle

not for single instruments

Oven

Chemical

Ethylene oxide

Select a suitable indicator of sterilisation - see table below.
Be careful to select the best type for the chosen sterilisation method. Remember that Browne's tubes are available to indicate changes at several different changes, and that different types of chemical strip are for use in the autoclave to those designed for use with ethylene oxide.

Method of sterilisation

Bowie Dick tape

Spore test strips

Browne's tubes

Chemical strips

Autoclave

Beige to brown

Best method

Oven

Chemical

Ethylene oxide

Yellow to red

Carefully package up your instruments; if using chemical strips - these should be placed within the packaging. Bowie Dick tape is usually used to seal up packages or a strip can be placed on the outer of the sterilising container. Browne's tubes are placed within the autoclave or oven itself, whilst spore test strips may be placed within the autoclave, oven or ethylene oxide sterilising unit.

Check the package for any sign of damage.

Label clearly with waterproof marker the date of sterilisation, contents of the package (EG cat spay kit) and your initials.

NB. If ethylene oxide is used, don't forget to place the gas ampoule within the polythene liner bag and seal with a metal tie.

3. Gowns & Drapes

Select the appropriate gown/drapes.

Ensure that you have a clean, flat and dry surface upon which to work.

Lay out the gown or drape and inspect for any evidence of dirt. If blood is found, the item should be scrubbed thoroughly in tepid water and relaundered since protein based stains will decrease the efficiency of sterilisation.

Remove any animal hairs or fluff with a tape roller.

Carefully fold the item:

i) Gowns - with the gown lying on the table with the inside surface facing down, lay flat, ensure arm and ties are folded onto the gown, fold in half lengthways, and again in half lengthways, then fold the top and bottom edges to the middle, then fold in half (the gown is then ready to be picked up by the inside of the collar).
ii) Drapes - lay out flat, concertina widthways and then lengthways.
Select suitable packing material appropriate for the type of sterilisation employed.

Select a suitable method of sterilisation indication appropriate for the type of sterilisation employed.

Carefully package up your gown/drapes.

Check the package for any sign of damage.

Label clearly with waterproof marker the date of sterilisation, contents of the package (eg. cat spay kit) and your initials.

Asepsis & Sterilisation - Answers

Arlo Guthrie — Tue, 21 Apr 2009 07:01:31 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:01:31

ANSWERS

What is meant by "aseptic technique"?
All the steps taken to prevent contact with micro-organisms.

What is the term used to describe the presence of pathogens or their toxic products in the blood or tissues of the patient?
Sepsis (commonly known as infection).

In what part of the body would septicaemia be found?
The blood stream.

Why might advanced periodontal disease predispose a patient to renal and cardiac problems?
Bacteria have a direct route to the blood stream via oral cavities and lesions, and as you know, the oral cavity is seething with bacteria. These bacteria then migrate to other areas of the body where they reproduce further and cause damage to cells, tissues and organs.

Describe the difference between asepsis and sterilisation.
Asepsis means the complete exclusion of all micro-organisms and spores, whilst antisepsis describes the prevention of sepsis (infection) by the destruction or inhibition of micro-organisms using an agent that is safe and effective upon living tissue.

What is the difference between disinfection and sterilisation?
Disinfection is the removal of micro-organisms but not necessarily spores; sterilisation is the destruction of ALL micro-organisms and spores.

When do most surgical wound infections occur and why?
Intra-operatively (ie. at the time of surgery) as a result of poor aseptic technique.

What is the difference between endogenous and exogenous micro-organisms?
Endogenous micro-organisms originate from within the body of the patient, whilst exogenous micro-organisms originate from the exterior of the body and may include contaminates from the skin and coat aswell as environment sources of micro-organisms such as the air and instruments or equipment.

List 4 factors that influence wound infection.

Virulence (potency) of the bacteria involved.

Surgical trauma and damage to the vascular supply.

Impaired immune response which will lower the resistance of the patient.

Contamination of the wound.

Differentiate between a clean-contaminated and a contaminated wound.
A clean contaminated wound is a surgical wound made under aseptic conditions but penetrating the oro-pharynx, respiratory, alimentary or uro-genital tracts but without undue contamination or spillage. A contaminated wound is a fresh traumatic wound of less than 6 hours duration or a major break in aseptic technique. Also surgery that encounters inflamation.

Give an example of a clean-contaminated wound.
End to end anastomosis.

What are the 2 main types of sterilisation?

Cold sterilisation.

Heat sterilisation.

List 4 types of cold sterilisation.

Ethylene oxide.

Chemical solutions such as Novasapa.

Gamma irradiation.

List 4 disadvantages of sterilisation by ethylene oxide.

Toxicity.

Irritant to tissue.

Extremely inflammable.

Time consuming.

How does ethylene oxide work?
It inactivates the DNA of viruses, bacterial cells and spores and fungi, thus rendering them incapable of reproduction.

A pack of instruments is put into the ethylene oxide steriliser at 7pm on Monday. At what time and day would this pack be safe to use?
The pack would be ready at 9pm on Wednesday (after 36 hours; comprising of a 12hour sterilisation period, a 2 hour aeration period where the container/cupboard remains shut, plus 24 hours ventilation after removal from the steriliser).

At what temperature is ethylene oxide sterilisation performed?
20°C.

What is the main advantage of ethylene oxide sterilisation?
It is ideal for items that are destroyed by heat such as fibre-optic equipment, plastic items such as catheters, rubber items such as endotracheal tubes, delicate optical instruments, high-speed drills and burrs and battery operated drills.

What material should not be sterilised by ethylene oxide and why?
Polyvinylchloride (PVC) since it may react with the gas.

What colour are the stripes on ethylene oxide sterilisation indicator tape before and after exposure to the gas?
Yellow prior to exposure, and red after exposure.

What limitation is a concern when using ethylene oxide indicator tape?
The colour change takes place very soon after exposure to the gas, so there is no evidence that the correct duration of exposure was undertaken.

State 2 alternatives to ethylene oxide indicator tape.

Chemical indicator strips (these change colour after the correct exposure period).

Spore strips.

What is the main disadvantage of spore strips?
They do not provide an immediate indication of sterility since they must be incubated for 72 hours following the completion of the sterilisation cycle.

Why are formaldehyde and glutaraldehyde no longer in common use?
The fumes are extremely dangerous. COSSH regulations limit the use of both substances.

List 6 factors to be taken into consideration when using chemical solutions for sterilisation.

Sterilisation may not be guaranteed.

Care must be taken to use according to the manufacturers' instructions.

Do not use on equipment that may be damaged by moisture.

A lid must be placed over the sterilisation container to prevent evaporation and air-borne contaminants.

Items should be rinsed well in sterile water prior to use.

A fresh solution should be used for each batch of sterilising.

How do alcohol-based sterilisation solutions work?
By the denaturation and coagulation of proteins.

Why is sterilisation by gamma irradiation not undertaken in veterinary practices?
This is an extremely expensive, specialised and highly controlled method of sterilisation. It can only be carried out under strict controlled conditions within industry. You may find some pre-packed sterile items designed for individual use are sterilised by gamma irradiation such as suture materials and needles, dog and cat catheters and irrigation cannulae.

State the 2 main types of heat sterilisation.

Dry heat (ovens).

Steam under pressure (autoclaves).

List the 3 types of sterilisation oven and briefly describe each.

Hot-air oven - a small, but economical method now largely superseded by the autoclave.

High vacuum-assisted oven - a fully automatic and rapid method, but not commonly seen in veterinary practice.

Convection oven - these incorporate an air circulation device to achieve a uniform temperature, but are not commonly seen in veterinary practice.

Why must dry heat sterilisation be carried out at a higher temperature than moist heat sterilisation?
Micro-organisms are much more resistant to dry heat and therefore require temperatures of 150-180°C to guarantee sterilisation.

State the time and temperature recommended for the sterilisation of non-cutting instruments using a hot air oven.
160°C for 120 minutes.

State the 3 main types of autoclave and briefly describe each.

Vertical pressure cooker - A simple machine which operates by boiling water in a closed container with an air vent at the top; this is closed once the air has been evacuated and pressure of 15 psi is allowed to build up.

Horizontal/vertical downward displacement autoclave - An automatic, electrically operated boiler is employed as a source of steam. Air is driven out of the vent at the top effectively by downward displacement.

Vacuum assisted autoclave - This efficient and fully automatic autoclave uses a vacuum pump to rapidly evacuate air from the chamber at the beginning of the cycle enabling steam penetration. A second vacuum withdraws moisture after sterilisation and dries the load.

Which type of autoclave is also known as a porous load autoclave?
The vacuum assisted autoclave.

If an autoclave were operating at 126°C at a pressure of 20 psi, what sterilising time would be necessary to ensure the destruction of micro-organisms?
10 Minutes.

List 5 factors to be taken into account when using an autoclave.

Ensure that the autoclave is not overloaded (there must be adequate space to allow the steam to circulate freely).

Ensure that the inlet and exhaust valves are not obstructed.

Effective penetration of steam is reliant upon the absence of grease and protein material.

Servicing should be carried out twice yearly (or every 3 months in the case of vacuum assisted autoclaves with a separate boiler).

Thermocouple testing is recommended at least annually. Thermocouples are electrical leads with temperature sensitive tips that can record the temperature throughout a cycle via a recording device outside of the autoclave.

State the 4 main methods of monitoring autoclave sterilisation efficiency and briefly describe each.

Bowie Dick tape - beige tape with chemical stripes that turn dark brown when a temperature of 121°C is reached.

Chemical indicator strips - these show a colour change (from yellow to purple) only when the correct temperature, pressure and time have been reached; different strips are available for different cycles.

Browne's tubes - small glass tubes filled with an orange-brown liquid that turns green when a certain temperature has been maintained for a required period of time; different tubes are available for different cycles and also for hot air ovens.

Spore test strips - these are impregnated with bacteria and are incubated for 72 hours after the cycle; a successful sterilisation process will obviously show no growth.

State 2 disadvantages of Bowie Dick tape.

It does not provide evidence that the required temperature was maintained for the correct duration.

It is designed for sterilising at 121°C (not 126 or 134°C).

Of the 3 methods listed in Q36, which is the most effective and why?
Chemical indicator strips, since they are the only method which shows that all 3 parameters are met (ie. temperature, pressure and time) and give immediate results once the sterilisation cycle is complete.

List 6 materials/containers used for the packing of supplies for sterilisation.

Nylon film.

Seal & peel pouches (made of paper and plastic).

Paper.

Linen sheets.

Metal drums.

Cardboard boxes/cartons.

How should sterile packs be stored?

In a dry, dust free environment with good ventilation (ideally within a closed cupboard).

Labelled with the date of sterilisation and the initials of the nurse who did the sterilising.

Packed loosely on shelves and handled as little as possible to minimise the risk of damage to the bags.

Checked regularly for perforation of the packaging and the date of sterilisation (unused packs should be resterilised every 6-8 weeks).

Asepsis & Sterilisation

Arlo Guthrie — Tue, 21 Apr 2009 07:00:33 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 08:00:33

QUESTIONS

What is meant by "aseptic technique"?

What is the term used to describe the presence of pathogens or their toxic products in the blood or tissues of the patient?

In what part of the body would septicaemia be found?

Why might advanced periodontal disease predispose a patient to renal and cardiac problems?

Describe the difference between asepsis and sterilisation.

What is the difference between disinfection and sterilisation?

When do most surgical wound infections occur and why?

What is the difference between endogenous and exogenous micro-organisms?

List 4 factors that influence wound infection.

Differentiate between a clean-contaminated and a contaminated wound.

Give an example of a clean-contaminated wound.

What are the 2 main types of sterilisation?

List 4 types of cold sterilisation.

List 4 disadvantages of sterilisation by ethylene oxide.

How does ethylene oxide work?

A pack of instruments is put into the ethylene oxide steriliser at 7pm on Monday. At what time and day would this pack be safe to use?

At what temperature is ethylene oxide sterilisation performed?

What is the main advantage of ethylene oxide sterilisation?

What material should not be sterilised by ethylene oxide and why?

What colour are the stripes on ethylene oxide sterilisation indicator tape before and after exposure to the gas?

What limitation is a concern when using ethylene oxide indicator tape?

State 2 alternatives to ethylene oxide indicator tape.

What is the main disadvantage of spore strips?

Why are formaldehyde and glutaraldehyde no longer in common use?

List 6 factors to be taken into consideration when using chemical solutions for sterilisation.

How do alcohol-based sterilisation solutions work?

Why is sterilisation by gamma irradiation not undertaken in veterinary practices?

State the 2 main types of heat sterilisation.

List the 3 types of sterilisation oven and briefly describe each.

Why must dry heat sterilisation be carried out at a higher temperature than moist heat sterilisation?

State the time and temperature recommended for the sterilisation of non-cutting instruments using a hot air oven.

State the 3 main types of autoclave and briefly describe each.

Which type of autoclave is also known as a porous load autoclave?

If an autoclave were operating at 126°C at a pressure of 20 psi, what sterilising time would be necessary to ensure the destruction of micro-organisms?

List 5 factors to be taken into account when using an autoclave.

State the 4 main methods of monitoring autoclave sterilisation efficiency and briefly describe each.

State 2 disadvantages of Bowie Dick tape.

Of the 3 methods listed in Q36, which is the most effective and why?

List 6 materials/containers used for the packing of supplies for sterilisation.

How should sterile packs be stored?

Theatre Practice

Arlo Guthrie — Tue, 21 Apr 2009 06:59:09 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:59:09

Introduction
Theatre practice describes the procedures undertaken in order to ensure the smooth running of the operating theatre. Maintenance of hygiene and the provision of an aseptic environment are essential.

This chapter covers the important aspects that together comprise a well-run theatre from care of instruments and equipment through to planning the order of surgical procedures.

Learning Objectives
The learning objectives are as follows:

To understand the importance of asepsis and sterilisation and know how to implement such.

To comprehend the essential factors necessary in the design and planning of an operating theatre, and be able to outline good personnel conduct and recognise significant health and safety risks.

To perform "scrubbing up", "gowning" and "gloving".

To be able to recognise and describe common surgical instruments, aswell as understanding methods involved in their cleaning, storage and sterilisation. (This module also covers the laying out of an instrument trolley).

To be able to recognise and describe commonly used suture needles and materials.

To comprehend and implement patient care procedures pre and during surgery.

To comprehend and implement post-operative patient care procedures.

Radiography - Glossary

Arlo Guthrie — Tue, 21 Apr 2009 06:55:56 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:55:56

Actual focal spot = The area of the tungsten target upon which the stream of electrons produced at the cathode impinge at high speed.

Angiocardiography = Radiography of the heart chambers and major vessels using water soluble iodine containing contrast to opacify the cardiovascular system.

Anode = The tube head target; the positively charged electrode upon which the electron stream from the cathode collide.

Arthrography = Contrast radiography of a joint space used to demonstrate capsule distension or rupture and articular cartilage problems.

Atom = The smallest possible particle of an element retaining all properties of the element in question; it consists of protons, neutrons and electrons.

Atomic number = The number denoting the unique quantity of protons possessed by an element.

Bronchography = Contrast radiography of the bronchial tree; used to diagnose conditions such as bronchial foreign bodies, tumours or lung lobe torsion.

Cathode = The tube head filament; the negatively charged electrode where the electron stream is generated by thermionic emission.

Clearing time = The time taken for removal of unexposed halide during fixing.

Collimation = Determination of the limits of an area of interest to be radiographed.

Compression band = A tight support used to reduce large areas such as the chest and abdomen during radiography.

Contrast = The differences between shades visible on a radiograph.

Contrast media = Agents used in order to opacify a structure or organ enabling better visualisation of the structure itself of mucosal surface.

Contrast radiography = Radiographic studies utilising contrast media allowing improved assessment of the shape, size and position of a structure or organ.

Controlled area = An area within a room designated specifically for radiography as demarcated by the radiation protection adviser.

Crossed grid = A type of stationary grid containing a series of lead strips alternating with strips of a radiolucent material; these strips run both vertically and horizontally making the crossed grid very efficient, but expensive.

Definition = The sharpness or clarity of the structures of interest visible on a radiograph.

Density = The degree of blackness visible on a radiograph.

Developer = An alkaline solution containing phenidone-hydroquinone responsible for the first stage of processing a radiograph. During development, the exposed silver bromide crystals of the film emulsion are converted into grains of black metallic silver while the bromide ions are released into solution.

Dichroic fog = Yellow staining marring a developed radiograph; the cause is insufficient rinsing or exhausted fixer.

Double contrast radiography = Radiography of a hollow organ using both a positive contrast agent (usually water soluble iodine) and a negative contrast agent (room air or oxygen). The inner lining of the organ is coated with the positive agent providing better visualisation of the mucosae, while the gas within the organ prevents the obscuring of small defects.

Effective focal spot = The small area from which the x-ray beam appears to originate due to the angulation (20 degrees to the vertical) of the target; this should ideally be a point source in order to produce fine radiographic definition.

Electron = A negatively charged particle revolving around the nucleus of an atom; electrons orbit in planes or "shells".

Element = A simple chemical substance that cannot be decomposed by usual chemical means; an element may be a constituent of a compound, which is a combination of 2 or more elements.

Filament = The tungsten coil of the tube head cathode (negatively charged electrode); it is from the filament that electrons are produced by thermionic emission.

Film focal distance = The distance between the focal spot and the radiographic film; usually 75cm-100cm.

Film-screen combination = The selection of a compatible film type and intensifying screen of a certain speed and definition.

Fixer = An acidic solution containing thiosulphate responsible for the removal of unexposed silver halide crystals leaving a permanent image that may be viewed in normal light. Fixer also hardens the film emulsion making it more resistant to scratches and abrasions.

Flat film = A low contrast radiograph showing mainly shades of grey; the cause is usually under-development.

Focal spot size = The size of the area from which the primary beam emerges. Fine focus will produce a smaller focal spot size and thus better definition than coarse (or broad) focus. Coarse focus is suitable for dense areas where higher exposures are required.

Focussed grid = A stationary grid consisting of central vertical strips of alternating lead and radiolucent material and gradually sloping strips on either side. The focussed grid is superior to parallel grids since the divergence of the primary beam is taken into account, thus avoiding "grid cut off".

Fogging = Term describing undesirable darkening of a radiograph. Causes may be environmental (safe-light fog), technical (over-exposure or scatter) or developmental (over-development). See also dichroic fog.

Gastrogram = A contrast radiograph of the stomach.

Grid = A special piece of radiographic equipment used to prevent scatter consisting of alternating strips of lead and radiolucent material. The grid is placed between the patient and the x-ray cassette where obliquely moving scatter is absorbed by the lead strips, whilst undeflected photons pass through the radiolucent interfaces.

Grid factor = The amount by which mAs must be increased by in order to compensate for the absorption of some of the primary beam when a grid is used. The grid factor is specific to each grid, but generally is around 2.5-3.

Grid ratio = The ratio of the height of the lead strips to the width of the radiolucent interspaces. Grids with a large ratio are more efficient at absorbing scatter, usual ratios are between 5:1-10:1.

Intensifying screen = A screen within the x-ray cassette comprising phosphorescent crystals that serve to intensify the effect of the x-rays upon the radiographic film.

Ionising radiation = The emanation of energy in the form of electromagnetic waves of x-rays.

Kilovoltage (kV) = The potential difference applied between the filament and target of the x-ray tube head; the penetrating power of the primary beam.

Light beam diaphragm = Adjustable device used to control the size of the emergent x-ray beam; device for the purpose of collimation.

Line voltage compensator = Device used to control fluctuations in the mains electricity.

Milliamperage (mA) = The quantity of x-rays in the emergent beam; allows determination of the tube current and the intensity of the primary beam.

Milliampere seconds (mAs) = Combination of x-ray quantity and exposure time.

Monochromatic film = Film sensitive only to blue light emitting screens.

Movement blur = Undesirable effect found on exposed films due to instability of equipment such as the tube head or cassette or patient activity.

Myelography = Radiographic examination of the spinal cord following the introduction of a radio-opaque contrast medium by means of cisternal or lumbar puncture into the sub-arachnoid space.

Negative contrast agent = Radio-opaque medium allowing better visualisation of the structures of interest on a radiograph; negative agents are gases (usually air or oxygen) and appear darker than the surrounding tissues.

Neutron = Uncharged charged particles found within the nucleus of an atom.

Non-screen film = Radiographic film that is not used with intensifying screens; it is contained within a plastic envelope rather than a cassette. Very fine detail is produced although longer exposure times are necessary. Non-screen film is used almost exclusively for intra-oral radiography.

Object film distance = The distance between the area of interest to be radiographed and the film; they should be as close to one another as possible to avoid magnification and distortion of the image.

Orthochromatic film = Radiographic film sensitive to both blue and green light emitting screens.

Parallel grid = A type of stationary grid comprising alternating vertical strips of lead and radiolucent material. The perimeter of the exposed radiograph may be of poor quality due to the absorption of x-ray photons from the edge of the primary beam.

Penumbra effect = Undesirable effect causing blurring of the image due to the use of a large focal spot size.

Photon = Energy packet released when rapidly moving electrons are slowed down or halted.

Pneumocystogram = A contrast radiograph of the bladder utilising gas as a negative contrast agent to enable better visualisation.

Portal venography = Contrast radiography of the vasculature of the liver involving the introduction of a contrast agent via the hepatic portal vein.

Positive contrast agent = An element used in radiography to outline endothelial or mucosal surfaces thus allowing improved visualisation of the position, size and shape of the structure or tissues of interest. Positive agents appear whiter than normal tissues due to their high atomic number.

Potter Bucky diaphragm = An expensive, but highly effective moving grid incorporated in the radiography table-top. Grid lines are not seen on the exposed film unlike those found following the use of stationary grids.

Primary beam = The useful beam of polychromatic x-ray photons used to create an image on radiographic film.

Proton = Positively charged particle contained within the nucleus of an atom.

Pseudo-focussed grid = A type of stationary grid comprising vertical slats that become progressively shorter towards the edges, thus reducing the amount by which the perimeter of the primary beam is absorbed.

Radiation protection advisor (RPA) = Experienced external adviser responsible for the demarcation of the controlled area and the drawing up of local rules and written systems of work.

Radiation protection supervisor (RPS) = A senior veterinary surgeon responsible for ensuring that all radiographic procedures are undertaken safely and in accordance with the local rules and written systems of work.

Radiography = The production of diagnostic film records of internal body structures by the exposure of film specially sensitised to x-rays.

Radiology = The science of radiation and its use in the diagnosis and treatment of disease.

Reduction = The chemical process by which a radiographic image is produced during development; the silver bromide ions of the film emulsion are converted into crystals of metallic silver whilst the bromide ions are lost in solution.

Retrograde urethrogram = Contrast radiograph of the male urethra using water soluble iodine containing contrast medium in order to provide improved visualisation; indicated in cases such as haematuria, dysuria and urinary incontinence.

Retrograde vaginourethrogram = Contrast radiograph of the female urethra using water soluble iodine containing contrast medium introduced via a Foley catheter.

Scattered radiation = Secondary radiation produced by lower energy x-ray photons that emerge from the patient in random directions; representative of a serious hazard if steps are not taken to prevent risk to personnel.

Soot and whitewash = Term describing an exposed film showing very high contrast and few shades of grey; the cause is the use of a too low a kilovoltage.

Stop bath = The intermediate wash bath in manual development; usually water, but may be a weak acid which is better able to halt the development and more compatible with the fixer which is also acidic.

Tanning = Term describing the hardening of the developed radiograph during fixing.

Target = The positively charged electrode of the x-ray tube head (anode) upon which the electrons generated at the filament impinge. The target may be stationary and mounted on a copper stem to transport heat to the oil bath, or rotating and mounted on molybdenum rod to prevent heat being conducted to motor.

Thermionic emission = The process by which an electron cloud is released following heating of the filament, bypassing an electrical current through it.

X-ray tube head = The part of the x-ray machine where x-rays are generated; it contains the filament and target which are essential components necessary for the formation of ionising radiations.

Radiography - Summary & Further Reading

Arlo Guthrie — Tue, 21 Apr 2009 06:55:17 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:55:17

Radiography is a complex subject, and the importance of practical experience cannot be stressed enough. Obviously, it is not possible to take lots of unnecessary exposures due to the health risk, but the positioning of toy animals will be very helpful.

Further reading:

Practical Veterinary Nursing - Edited by Gillian Simpson (BSAVA) - Radiography by E Munro MA VetMB DVR MRCVS.

Veterinary Nursing - Edited by D R Lane & B Cooper (Butterworth Heinemann) - Chapter 24 Radiography by R Dennis.

Safety Checks - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 06:54:28 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:54:28

INTRODUCTION
Radiography is a branch of veterinary science with many potential hazards. X-rays have an adverse effect on living tissue caused by cellular chemical reactions. X-rays are latent and cumulative, and most danger arises from repeated exposure to small amounts of radiation. The tests described here are of such importance in general practice that they often are incorporated into the practical examination. Not all of the tests are directly related to occupational dangers, but procedures that help to prevent the production of poor quality, non-diagnostic radiographs can only be beneficial to both the staff and patients involved.

TESTING FOR SCATTERED RADIATION
Scattered radiation is also known as secondary radiation. Scatter occurs when x-ray photons interact with the tissues, lose some of their energy and emerge from the patient in random direction as photons of lower energy. Scattered radiation travels in all directions and may rebound off the walls, table or floor. Scatter is not only undesirable due to the fogging effect that it has on the radiographic image, but also because of the radiation risk to personnel. In order to assess levels of scattered radiation, leave a metal instrument such as a pair of scissors on an unexposed x-ray cassette placed in the controlled area for radiography. Develop the film after one week. An unexposed film will normally appear transparent. If the outline of the scissors is visible, scatter is at an unacceptable level.

The Radiation Protection Supervisor is duty-bound to improve the situation before further radiographs are performed. Steps that may be taken include:

Servicing of the xray machine; this should be undertaken every 6 months or when a fault prevails.

The use of grids when radiographs of tissue deeper than 10cm are taken. The Potter-Bucky moving grid incorporated into the table top is by far the most expensive but also the most efficient.

Compression of large areas of soft tissue.

Decrease the penetrating power (KV) where possible.

Collimate the light beam diaphragm to as small an area as possible; if the x-ray machine is still fitted with a cone this should be updated.

The use of lead-backed cassettes and a lead-backed table top.

Personnel involved in radiographic procedures should be issued with a personal dose-meter enabling external assessment of ionising radiation levels.

TESTING FOR FOGGING BY THE SAFE-LIGHT
Poor quality radiographs mean that repeated exposures need to be made; thus subjecting patient and personnel to further doses of ionising radiation. Developing faults are frustrating and unnecessary. Fogging is not only caused by scatter; it can also be caused by the darkroom safelight. To check the efficiency of the safelight, lay a metal instrument such as a pair of scissors on a cassette containing unexposed film. Place this in the darkroom on the work-bench with the safelight switched on. Leave for 2 minutes before processing the film. If the scissors are visible on the exposed film, fogging has occurred. The following steps should be taken if safelight fogging is present:

Check that the bulb wattage is no greater than 25W; replace the bulb if this is the case.

Ensure that the correct colour filter is used for the type of film in use; brown or amber for blue light sensitive film and red for green light sensitive film.

Check for cracks in the filter and replace if damaged.

Check that the safelight is not too close to the film handing area.

ASSESSMENT FOR UNDER-DEVELOPMENT
Underdevelopment is the most common developing fault, although with many practices now using automatic processors this problem is less frequent. The "finger test" is a simple method employed to test for underdevelopment. Place your finger between the exposed x-ray film and the viewer, choosing an area not occupied by the view of the patient. The film should be completely black, and if the finger is visible through the film - underdevelopment is evident. Corrective measures for underdevelopment include:

Ensure that the developer is used at the correct temperature; 20°C for manual developing, 28°C for automatic processing.

Regular replenishment of developer according to the manufacturers instructions; ensure that the concentration of the solution is correct.

Use a developer recommended by the manufacturer of the processor.

Mix the developer well prior to use when manually processing.

LIGHT BEAM DIAPHRAGM ALIGNMENT TEST
The light beam diaphragm is the part of the x-ray machine which is attached to the x-ray tube head in order to produce light over the area covered by the primary beam. A shadow cross shows the position of the central ray and enables accurate collimation by adjustment of the size of the light area. The centre of the cross is situated in the centre of the area of interest with the beam collimated as tightly as possible.

To check the light beam diaphragm alignment, mark the corners of the light image with radiopaque markers. Take an exposure and develop the film. Now compare the position of the markers on the cassette with those on the exposed image. Any difference in position indicates a fault with the LBD. An approved engineer should be called to service the machine and right the fault; special calibration tests will be necessary and these should only be undertaken by an expert.

FILM - SCREEN CONTACT ASSESSMENT
X-ray cassettes usually contain 2 intensifying screens, the purpose of which are to strengthen the effect of x-rays on the film. They consist of a plastic or carbon fibre base covered with a white reflective surface and a coating of luminescent phosphors. Calcium tungstate phosphors emit blue light when irradiated, while rare earth phosphors emit blue or green light. (It is important to use the correct film-screen combination). The light emitted greatly reduces the exposure necessary and is beneficial therefore in reducing both scattered radiation and movement blur. The film is placed within the cassette between the screens and close film-screen contact is provided by a thick felt pressure pad sited between the rear screen and the back plate of the cassette. Poor film-screen contact causes blurring of the radiographic image in the affected areas.

To test film-screen contact, scatter an x-ray plate with small metal objects such as paper clips. Ensure that these are placed close to the cassette edges in addition to centrally. Expose and develop the film. Assessment of quality may now be made; the pressure pad should be replaced if any part of the exposed film shows blurring. You may be confronted with chicken wire in the practical examination; this serves the same purpose as the paper clips.

Health & Safety - Answers

Arlo Guthrie — Tue, 21 Apr 2009 06:53:12 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:53:12

ANSWERS

What 2 factors ensure the safety of the metal casing surrounding the entire x-ray tube?

It is earthed.

It is lead lined

What must be permanently fixed across the tube window, and why is its removal illegal?
An aluminium filter; the purpose of which is to remove low energy photons that are not powerful enough to pass through the patient, but may be absorbed or scattered. These represent a serious hazard.

What is the collimation device of choice, and how is this superior to the old style cone?
The light beam diaphragm. This allows much greater accuracy in collimation and centering of the primary beam. Collimation to the smallest area possible poses less risk of scattered radiation.

What is meant by a ratings chart?
The details of maximum safe combinations of kV, mA and mAs according to the x-ray machine manufacturer's recommendations. These safety guidelines are important in order to prevent overload by excess heat production.

What is scattered radiation?
Secondary radiation produced by incident photons which interact with the tissues of the patient and bounce off in random directions as lower energy x-ray photons. Scatter represents a serious hazard.

Is scattered radiation more of a risk in large or small patients (state your reason)?
Large patients, since higher kVs are required in order to penetrate thick or dense tissues. The higher the kV, the greater the risk from scatter. In small patients, most scatter is reabsorbed by the animal's body tissues.

In addition to representing a serious health hazard, how else is scatter a problem?

May cause fogging of the radiographic image.

May cause flat films of low contrast.

May cause blurring of the image margins.

List precautions that may be taken to reduce radiation risks to personnel.

Collimation of the primary beam to as smaller area as possible.

Use the lowest kV possible.

Use a grid for tissues of a depth greater than 10cm.

Use a compression band for radiography of thick areas such as the abdomen.

Ensure that lead is sandwiched between the cassette and tabletop to avoid back-scatter.

Always use safety clothing such as lead aprons, sleeves and gloves.

Avoid manual restraint.

Ensure that staff rotation is employed for radiographic procedures.

A lead lined wall or lead screen should be positioned between the radiographer and the patient.

List categories of person who should not be involved in radiography.

The general public (owners may want to be present, but MUST be dissuaded).

Pregnant women and personnel actively trying to conceive.

Personnel under the age of 18 years.

Any member of staff who has not been fully trained in all aspects of radiography and ionising safety regulations.

What health hazards are posed by ionising radiations?

Somatic effects - causing changes in the tissues of the body.

Carcinogenic effects - causing tumours.

Genetic effects - causing mutations in the chromosomes of germ cells.

X-rays are described as latent and cumulative. Explain these terms in respect of radiation hazards.
Most danger from radiation arises from repeated exposure to small quantities. Since x-rays are both invisible and painless, it is not possible to see their effects until irreversible damage has been done.

What law governs the use of radiation and radioactive materials?
The Ionising Radiation Regulations 1999.

All veterinary personnel involved in radiography must have read and understood the Ionising Radiation Regulations. In addition, guidance notes should be available that explain the law with respect to radiography in veterinary practice. What is the name of this booklet?
The Guidance Notes for the Protection of Persons against Ionising Radiations Arising from Veterinary Use (July 1988). This is currently being re-written (as at 30/04/2001).

What is the role of the radiation protection supervisor?
A senior member of staff who holds the responsibility for radiation safety in accordance with the regulations and local rules relevant to ionising radiations and radiographic procedures.

What is the role of the radiation protection adviser?
An external adviser holding the Diploma in Veterinary Radiography. It is the responsibility of the RPA to demarcate the controlled area and draw up local rules and written systems of work. Things may change in 2003 in light of IRR99.

List 10 specifications that must be applied in relation to the controlled area.

The area must be physically demarcated and clearly labelled.

The radiation warning symbol must be displayed on the door.

A red light or sign must be displayed on the door and illuminated when radiography is in progress.

The area should ideally be within a specific room designed for radiography.

The room should possess thick walls; ideally lead-ply or barium plaster reinforced.

2 members of staff should have room to stand at least 2m away from the x-ray tube head.

The local rules and written systems of work must be displayed

A lead-lined radiography table, or lead sheeting of a thickness of at least 1mm should be used.

Service records and exposure charts should be easily accessible.

Safety clothing and dosemeters should always be worn.

How should lead safety garments be stored and serviced?
Aprons, gloves and sleeves should always be stored flat. Aprons must be hung on strong wooden coat hangers or purpose built rails. All lead garments should be periodically radiographed in order to detect any small cracks or holes that may not be immediately obvious.

Describe the 2 types of dosemeter commonly used in veterinary radiography.

Film badges - these contain a small piece of x-ray film.

Thermoluminescent badges - these contain radiation sensitive crystals.

Health & Safety

Arlo Guthrie — Tue, 21 Apr 2009 06:52:23 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:52:23

Health & Safety

QUESTIONS

What 2 factors ensure the safety of the metal casing surrounding the entire x-ray tube?

What must be permanently fixed across the tube window, and why is its removal illegal?

What is the collimation device of choice, and how is this superior to the old style cone?

What is meant by a ratings chart?

What is scattered radiation?

Is scattered radiation more of a risk in large or small patients (state your reason)?

In addition to representing a serious health hazard, how else is scatter a problem?

List precautions that may be taken to reduce radiation risks to personnel.

List categories of person who should not be involved in radiography.

What health hazards are posed by ionising radiations?

X-rays are described as latent and cumulative. Explain these terms in respect of radiation hazards.

What law governs the use of radiation and radioactive materials?

All veterinary personnel involved in radiography must have read and understood the Ionising Radiation Regulations. In addition, guidance notes should be available that explain the law with respect to radiography in veterinary practice. What is the name of this booklet?

What is the role of the radiation protection supervisor?

What is the role of the radiation protection adviser?

List 10 specifications that must be applied in relation to the controlled area.

How should lead safety garments be stored and serviced?

Describe the 2 types of dosemeter commonly used in veterinary radiography.

Health & Safety

Arlo Guthrie — Tue, 21 Apr 2009 06:51:59 GMT
Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:51:59

QUESTIONS

What 2 factors ensure the safety of the metal casing surrounding the entire x-ray tube?

What must be permanently fixed across the tube window, and why is its removal illegal?

What is the collimation device of choice, and how is this superior to the old style cone?

What is meant by a ratings chart?

What is scattered radiation?

Is scattered radiation more of a risk in large or small patients (state your reason)?

In addition to representing a serious health hazard, how else is scatter a problem?

List precautions that may be taken to reduce radiation risks to personnel.

List categories of person who should not be involved in radiography.

What health hazards are posed by ionising radiations?

X-rays are described as latent and cumulative. Explain these terms in respect of radiation hazards.

What law governs the use of radiation and radioactive materials?

All veterinary personnel involved in radiography must have read and understood the Ionising Radiation Regulations. In addition, guidance notes should be available that explain the law with respect to radiography in veterinary practice. What is the name of this booklet?

What is the role of the radiation protection supervisor?

What is the role of the radiation protection adviser?

List 10 specifications that must be applied in relation to the controlled area.

How should lead safety garments be stored and serviced?

Describe the 2 types of dosemeter commonly used in veterinary radiography.

Contrast Radiography - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 06:51:07 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:51:07

INTRODUCTION
Contrast radiography allows better visualisation of soft tissue structures than plain film radiographs. Studies with which you should be familiar are:

The gastrointestinal tract and the use of barium as a contrast medium.

The urogenital system and the use of air and water soluble iodine contrast media.

The spinal cord and the use of low osmolar, non-ionic water soluble contrast media.

In all cases, plain radiographs should be taken to check the positioning of the patient and exposures before starting the contrast examination.

BARIUM
Barium is available as a ready-made paste or suspension, or as a powder, which is mixed with water to achieve the desired consistency. It is a positive contrast agent; and will thus appear more opaque (whiter) than the surrounding tissues. It is excellent in that it provides very fine mucosal detail and is therefore ideal for use in studies of the oesophagus, stomach and intestines. A barium series is a sequence of radiographs taken every 15-60 minutes following the passage of the contrast media from the oesophagus through to the colon. Barium may be given orally alone, mixed with a small portion of food or as an enema and is therefore quite versatile. It does have some limitations though, and these are listed below:

Heavy sedation or anaesthesia are contraindicated if oral barium is to be given.

Risk of aspiration pneumonia with orally administered barium.

Food should be withheld for 24 hours prior to the procedure.

Contraindicated if a perforation is suspected; use water soluble iodine instead.

Dosage guide:
Enemata = 10mls/kg.
Per os = 8-12mls/kg for cats and small dogs; 5-7mls/kg for larger dogs.
Via stomach tube = 15-100mls depending on patient size and rate of gastric emptying (Glucagon may be given to slow the rate of gastric emptying).

AIR AND WATER SOLUBLE IODINE CONTRAST MEDIA
Air is a NEGATIVE CONTRAST agent, which means that it will appear less opaque on a radiograph (blacker) than the surrounding tissues. Room air is most commonly used, although oxygen, carbon dioxide or nitrous oxide are also suitable. Air is used to inflate hollow organs such as the stomach or bladder in order provide effective visualisation. Water soluble iodine preparations are POSITIVE contrast agents and will appear more opaque than the surrounding tissues. Commonly used are Conray and Urografin. These may be administered intravenously for examination of the kidneys and ureters or via a urinary catheter for examination of the lower urinary tract. In addition, they may be given orally to visualise the stomach, but are less effective than barium due to their hypertonicity, which causes dilution by the gastrointestinal secretions. A DOUBLE CONTRAST radiograph of a hollow organ utilises both negative and positive agents in order to provide good mucosal detail without obscuring small details within the organ itself. Important terminology to remember:

The prefix "pneumo" denotes a negative contrast radiograph.

Gastrogram = contrast radiograph of the stomach.

Urogram = contrast radiograph of the kidneys and ureters (2 methods: bolus or infusion).

Cystogram = contrast radiograph of the stomach.

Retrograde urethrogram = contrast radiograph of the male urethra.

Retrograde vaginourethrogram = contrast radiograph of the female urethra.

Dosage guide:
Gastrogram - 15-100 mls Gastro-conray via stomach tube (followed by 20mls/kg air for double contrast gastrogram).
Bolus Urogram - up to 850mg of iodine/kg (@ 50mls for a 25kg dog) intravenously as a rapid injection.
Infusion Urogram - up to 1200mg of iodine/kg (@ 200mls for a 25kg dog) intravenously as a slow infusion diluted with saline.
Cystogram - 50-300mls iodine for positive contrast, 30-300mls air for negative contrast, 2-15mls iodine followed by air until bladder palpates taut; all given via urinary catheter.
Retrograde urethrogram - 5-15mls iodine via urinary catheter.
Retrograde vaginourethrogram - up to 1ml/kg via Foley catheter taken utmost care to avoid vaginal rupture

LOW OSMOLAR, NON-IONIC WATER SOLUBLE CONTRAST AGENTS
Low osmolar, non-ionic media are used in myelography and for some intravenous studies. Iopamidole and Iohexol are preferred since these are the least irritant to nervous tissue. The agent may be introduced by cisternal puncture (via insertion of the needle into the cisternal magna situated at the cranial end of the subarachnoid space just behind the skull), or by lumbar puncture (via insertion of the needle between the 4th and 5th or 5th and 6th lumbar vertebrae). General anaesthesia is essential in both cases to prevent movement during needle placement. A myelogram shows opacification of the cerebrospinal fluid and subsequently demonstrates the spinal cord. Tumours or prolapsed intervertebral discs which may not be evident on plain film radiographs may be identified.

Dosage guide:
0.3ml/kg of 330mg/ml Iopamidole or Iohexol; maximum 9mls.

Contrast Radiography - Answers

Arlo Guthrie — Tue, 21 Apr 2009 06:49:30 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:49:30

ANSWERS

What is the purpose of contrast radiography?
To allow better visualisation of structures or organs, either by altering the radio-opacity of the structure of interest or that of the surrounding tissues.

List the 3 main types of positive contrast agent and state their most common use.

Barium sulphate - investigation of the alimentary canal.

Water soluble iodine containing preparations - investigation of the urogenital system.

Low osmolar non-ionic media - myelography.

What is meant by double contrast radiography?
An investigation of a hollow organ using both a positive contrast medium (used to coat the inner lining) and a negative agent (gas or air, to distend that organ).

Why are heavy sedation or general anaesthesia contraindicated in the case of a "barium swallow"?
Due to the risk of regurgitation and aspiration.

Prior to a gastrogram, the patient may be given glucagon. Why?
In order to delay gastric emptying.

List 6 conditions that may indicate the need for a barium series.

Abdominal dilation.

Chronic vomiting.

Haematemesis.

Malabsorption.

Palpation of an abdominal mass.

Weight loss.

Name 2 contrast agents commonly used in myelography.

Iohexol.

Iopamidol.

State the site for lumbar puncture.
L4-5 or L6-7.

What is angiocardiography?
A technique used to demonstrate heart disease. The heart chambers are opacified by a bolus injection of water soluble iodine containing contrast medium.

List 2 conditions in which portal venography may aid a diagnosis.

Cirrhosis of the liver.

Congenital portosystemic shunts.

What is the name of the contrast medium used in bronchography?
Propyliodine.

What term describes contrast radiography of a joint space?
Arthrography.

Contrast Radiography

Arlo Guthrie — Tue, 21 Apr 2009 06:48:00 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:48:00

QUESTIONS

What is the purpose of contrast radiography?

List the 3 main types of positive contrast agent and state their most common use.

What is meant by double contrast radiography?

Why are heavy sedation or general anaesthesia contraindicated in the case of a "barium swallow"?

Prior to a gastrogram, the patient may be given glucagon. Why?

List 6 conditions that may indicate the need for a barium series.

Name 2 contrast agents commonly used in myelography.

State the site for lumbar puncture.

What is angiocardiography?

List 2 conditions in which portal venography may aid a diagnosis.

What is the name of the contrast medium used in bronchography?

What term describes contrast radiography of a joint space?

Automatic Processing - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 06:46:46 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:46:46

INTRODUCTION
Automatic processors are now frequently used in practice. They are expensive, but easy to maintain, quick and clean. Many developmental faults such as finger prints and dirt on the films, film damage caused by hangers and insufficient rinsing are virtually eliminated. The benefits far outweigh the expense, and once you have used an automatic processor, you will never want to return to manual processing!

TECHNIQUE

Prior to radiography, switch on the processor (this should ideally be done at the start of the day in order to prevent having to wait to develop films). Ensure that the safelight is operating, and that a supply of x-ray films of the correct film-screen combination are available. Check that films are inside the cassettes to be used and that the intensifying screens are clean. The water supply should be drained at the end of the working day, so ensure that this is replenished before use.

The processor must reach a temperature of 28° C before use. The warm up period is approximately 15 minutes, although this may take longer in cold weather.

It is sensible to pass a clean already-processed film through the processor prior to use to ensure correct operation and also to remove any old chemicals from the rollers.

Having performed the necessary radiographic procedures, take the cassette/s to the dark room. Ensure that the door is locked and that a light-proof curtain is drawn across to cover any cracks that may allow light to enter. Switch on the safe light and turn off the main light.

Open the cassette and carefully remove the exposed film. Films must only be handled with clean, dry hands; and by the perimeter only. Insert the film into the processor and gently check that the film is being pulled down into the machine before closing the lid. This should be undertaken in the shortest possible time, since prolonged exposure to the safelight may cause fogging.

Whilst the film is being developed; reload the cassette with a fresh film. Make sure that the unexposed films are kept in a safe, dry place and that the lid is kept firmly closed.

Once the exposed film is safely within the processor and the cassette reloaded, the main light may be switched on whilst you await the production of the radiograph. Never be impatient and pull through a film as it appears since this may damage the rollers.

Assess the film under the x-ray viewer for quality and place in a labelled envelope for the veterinary surgeon's perusal. Details to be recorded on the envelope are as follows:

The owner's surname.

Owner's address.

Patient's name.

Date.

Projections.

Further details; eg. Pre or post operative radiographs.

Having completed the day's radiographic procedures; the processor should be switched off at the mains. The water tank should be drained by turning off the appropriate tap. Always refer to the manufacturer's instructions or to a senior member of staff if you are in any doubt as to the operation of any aspect of the processor; it is an extremely important and not to mention, expensive piece of veterinary equipment and therefore needs to be treated with the utmost care.

Wipe the superficial rollers with a clean damp cloth, ensure that the work bench is clean and dry and check the stock levels of unexposed films. Switch off the lights and close the door.

Manual Processing - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 06:45:25 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:45:25

INTRODUCTION
Manual development of radiographs is more complicated and more time consuming than automatic processing. Most veterinary practices now have automatic processors, but manual development; old fashioned as it is, may still well crop up in the examinations. It is therefore important to be familiar with both techniques - not just the method employed at your own practice.

TECHNIQUE

Switch on the processor at the mains, allowing enough time for it to reach the correct temperature before use (20° C). Put on protective apron and gloves.

Check the levels of developer, stop bath and fixer BEFORE use and replenish if necessary.

Stir the developer well in order to mix the emulsion, but do not be over vigorous as this will cause the formation of air bubbles which may leave undesireable artefacts on the developed radiographs.

Ensure that the work bench is clean and dry, and that there are adequate supplies of film and hangers.
Two types of hangers are available; channel hangers and clip hangers. The channel variety are much less fiddly to use and therefore less likely to contribute to fingerprints and abrasions on the exposed film.

Check that the safelight is operational and that the filter is of the correct type for the films in use.
Brown/amber filter for blue light sensitive film; red filter for green light sensitive film.

Now you are ready to develop your films. Lock the darkroom door, switch on the safelight and switch off the main light.

Open the cassette and carefully remove the exposed film handling only with clean, dry hands and at the very perimeter. Never leave the exposed film lying around whilst you reload the cassette; always insert it into the hanger and place in the developing tank first. Once the film is within the hanger it should not be handled; use the handle of the hanger to transfer the film to the necessary area.

Develop the film according to the manufacturer's instructions; usually 3-5 minutes; always use a stop-watch - never estimate, as 3 minutes can seem like an eternity when you are alone in the darkroom!

Close the lid of the developer to prevent oxidisation and fogging. Whilst development is in progress, reload the cassette with a new film.
A favourite examination question is to name the chemical reaction that occurs during development - this is "reduction" and occurs when the silver bromide crystals of the x-ray film undergo chemical change to become metallic granules of silver (which show black on the exposed film); the bromide is released into the developing solution.

Agitate the hanger gently within the developing tank periodically to ensure that the film is evenly coated with fresh developer.

Remove the hanger and transfer to the stop bath; agitate for 10 seconds.
The stop bath is commonly filled with water, and this serves to arrest the developing process and prevent contamination of the fixer by the developer. A weak acid solution may be preferred since this is more compatible with the fixer (also acidic) and more efficient than water at stopping development due to the alteration in pH.

Now transfer the hanger to the fixer. After 30 seconds, the film will be safe to view. However, clearing (the removal of undeveloped halides) may take up to 3 minutes so it is prudent to wait a little longer or the film may still have a milky appearance.

Fix for a further 15 minutes to ensure that hardening has taken place.

Place the hanger in fresh, clean, constantly flowing water for half an hour to remove any residual chemicals. Insufficiently washed radiographs may be subject to yellow/brown stains.

Remove the film from the hanger and allow to dry in a clean, dust-free environment before placing into a labelled envelope.
See Practical Task: Automatic Processing for the labelling requirements.

Ensure that the work bench is clean and dry, cover the developer (this should always be covered except when in use), drain the wash water and switch off the lights.

Film Faults - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 06:43:50 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:43:50

FILM FAULT
POSSIBLE CAUSES SOLUTIONS

Abrasions
Mishandling of film during manual development. Handle film carefully; with clean, dry hands & holding at the edges only.

Dirty rollers on automatic processor. Clean the rollers.

Black film
Film has been exposed to normal light. Ensure that cassette is properly closed; check for cracks.

Black splash marks
Developer splashes causing local prolonged development. Exercise caution during manual development; do not agitate too vigorously & ensure that the work bench is clean & dry.

Brown/yellow stains (dichroic fog)
Insufficient rinsing during manual development. Rinse manually developed films for at least 15 minutes in constantly circulating clean water.

Exhausted fixer. Replenish fixer.

Contrast too high (soot & whitewash)
Underexposure. Increase KV.

Overdevelopment. Reduce developing time/temperature.

Contrast too low (flat film)
Fog from scattered radiation. Use a grid or collimate beam to a smaller area.

Overexposure. Reduce KV.

Underdevelopment. Increase developing time/temperature or replenish as necessary.

Crimp marks
Film creased during development. Handle film carefully and by the edges only; use the correct size hangers during manual development.

Definition poor
Inappropriate exposure settings. Adjust settings as necessary.

Movement blur. Stabilise patient & equipment.

Object-film distance too great. Reduce object-film distance.

Poor screen film contact. Use a new cassette.

Density too high
Overdevelopment Check temperature, concentration & development time & reduce levels as necessary.

Overexposure Reduce KV.

Density too low
Underdevelopment Increase temperature or concentration of the developer or increase development time.

Underexposure Increase KV.

Fogging
Scattered radiation Use a grid; collimate beam to a smaller area; store films away from radiography area.

Safelight problems Check that the correct filter is in use, that a bulb of 25W is used and that the light is not too close to the work bench.

Grease marks
Handling film with dirty fingers. Always ensure that hands are clean & dry; handle film by the edges only.

Lightning flashes
Static marks. Remove film slowly from the storage box when reloading cassette.

Movement blur
Cassette movement. Tape cassette to the table.

Instability of the tube head. Stabilise tube head.

Patient movement. Restrain patient (ideally under GA).

Patches of light & dark
Uneven development. Ensure that developer is regularly replenished and at the correct temperature.

Streaking
Dirty rinsing water. Use clean, constantly circulating water for rinsing.

Dirty hangers. Always use clean hangers.

Insufficient rinsing. Rinse for at least 15 minutes.

Watermarks from drying. X-rays must be hung flat in a warm, clean, dustfree and dry environment.

Transparent film
Unexposed film has been developed. Ensure that the x-ray machine is working; keep unused cassettes away from those in use.

Unsharpness (blurred margins of edges of structures)
Fog from scatter. Use grid; collimate beam to smaller area.

Movement blur. Stabilise equipment/patient.

Object-film distance too great. Reduce object-film distance.

Poor screen-film contact. Check cassette pressure pad.

White specks
Dirt on the intensifying screens. Clean intensifying screens regularly.

White splash marks
Fixer splashes. Agitate manually developed films with care & ensure that work bench is clean & dry.

Developing & Film Faults - Answers

Arlo Guthrie — Tue, 21 Apr 2009 06:42:35 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:42:35

ANSWERS

Why does bone appear whiter on a radiograph than fat?
Bone possesses a higher atomic number and higher specific gravity than fat, thus enabling the absorption of more x-ray photons resulting in a whiter image.

What are very dark shades on a radiograph likely to show?
Gas.

Why might a very thick area of tissue appear more radiopaque than a thin area of bone?
Thicker areas of tissue are able to absorb more x-ray photons than thin areas and therefore these may appear whiter even though you would generally expect to see darker shades.

What colour/s are unexposed radiographic films?
Green, fawn or mauve when examined in daylight.

The film is coated with an emulsion responsible for the production of the image. What does this emulsion consist of?
Silver bromide suspended in gelatin (with some silver iodide).

What attaches the emulsion layers to the transparent, polyester film base?
A sticky subbing layer.

What are the outer surfaces of the emulsion protected with?
The supercoat.

What is the main active ingredient in developer?
Phenidone-hydroquinone or metol-hydroquinone

List 3 other chemical agents present in developer.

Accelerator.

Buffer - maintains alkalinity of the solution.

Restrainer - reduces development fog.

During the development stage of processing, the silver bromide crystals of the film emulsion are converted into black metallic silver, whilst the bromide ions are released into solution. What is the name of this reaction?
Reduction.

What precautions may help arrest oxidation of the developer?

Keeping the developing tank covered.

Storing unused solution in the dark.

How frequently should developer be changed completely?
Every 3 months, or when an equal volume of replenisher has been used (which ever is sooner).

What is the main active ingredient in fixer?
Sodium thiosulphate or ammonium thiosulphate.

Is fixer acidic or alkaline?
Acidic.

Describe the reaction undergone during fixing.
The unexposed silver halide crystals are removed leaving a metallic silver image that may be viewed in normal light. Fixing renders the image permanent and insensitive to white light.

What name is given to describe the time taken for the removal of unexposed halide?
Clearing time.

What is the term that describes the hardening of film emulsion during fixing?
Tanning.

When should the fixing solution be changed completely?
When the clearing time has doubled.

What colour should the dark-room walls be painted and why?
Cream, in order to reflect the subdued lighting provided by the safe-light.

What is the maximum wattage suitable for a safe-light bulb?
25 watts.

What colour safe-light filter should be used for blue light sensitive film?
Brown or amber.

What colour safe-light filter should be used for green light sensitive film?
Red.

At what temperature should manual developer be maintained?
20° C.

At what temperature should automatic developer be maintained?
28° C.

List 4 faults associated with poor handling of film during processing.

Finger prints.

Emulsion damage.

Static marks (look like forked lightning).

Crimp marks.

List 2 faults associated with the mishandling of x-ray cassettes.

Light leaks.

Dirt, dust or hair on the intensifying screens.

What is dichroic fog?
Yellow stained films caused by insufficient rinsing or exhausted developer.

What colour will developer and fixer splashes appear on an exposed film?

Developer splashes - black.

Fixer splashes - white.

List 4 common environmental problems associated with processing.

Dirty or insufficient developer, fixer and wash water.

Light leaks in the dark-room.

Safe-light fogging.

Dusty drying environment.

List 4 advantages of automatic processing over manual development.

Speed.

Cleanliness.

Consistently high standard processing.

Solutions pumped in afresh for each film at a predetermined rate, thus minimising the risk of exhausted chemicals.

List 4 factors that may cause a radiograph to appear too dark.

Over-exposure.

Gross over-development.

Temperature of developer too high (also causing gross over-development).

Fogging.

List 4 factors that may cause a radiograph to appear too pale.

Under-exposure.

Under-development.

Temperature of developer too low (also causing under-development).

Too dilute or exhausted developer.

What are the 3 key terms used in the assessment of radiographic quality?

Contrast - difference between shades.

Definition - clarity of visible structures.

Density - degree of blackness/opacity.

Under-development is the most common processing fault. How might this be prevented?

Top up developer with replenishing solution as opposed to water.

Change the entire developer every 3 months.

Ensure that the developer is well maintained at the correct temperature.

Mix the developer well prior to use.

What is meant by a "soot and whitewash" film?
A high contrast radiograph showing a white image on a black background with few intermediate shades. The cause is insufficient penetrating power, therefore the kV should be increased for subsequent radiographs.

What is meant by a "flat" film?
A low contrast radiograph showing mainly shades of grey. The cause is usually under-development, but may occur as a result of fogging, or too high a kV.

Developing & Film Faults

Arlo Guthrie — Tue, 21 Apr 2009 06:41:55 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:41:55

QUESTIONS

Why does bone appear whiter on a radiograph than fat?

What are very dark shades on a radiograph likely to show?

Why might a very thick area of tissue appear more radiopaque than a thin area of bone?

What colour/s are unexposed radiographic films?

The film is coated with an emulsion responsible for the production of the image. What does this emulsion consist of?

What attaches the emulsion layers to the transparent, polyester film base?

What are the outer surfaces of the emulsion protected with?

What is the main active ingredient in developer?

List 3 other chemical agents present in developer.

During the development stage of processing, the silver bromide crystals of the film emulsion are converted into black metallic silver, whilst the bromide ions are released into solution. What is the name of this reaction?

What precautions may help arrest oxidation of the developer?

How frequently should developer be changed completely?

What is the main active ingredient in fixer?

Is fixer acidic or alkaline?

Describe the reaction undergone during fixing.

What name is given to describe the time taken for the removal of unexposed halide?

What is the term that describes the hardening of film emulsion during fixing?

When should the fixing solution be changed completely?

What colour should the dark-room walls be painted and why?

What is the maximum wattage suitable for a safe-light bulb?

What colour safe-light filter should be used for blue light sensitive film?

What colour safe-light filter should be used for green light sensitive film?

At what temperature should manual developer be maintained?

At what temperature should automatic developer be maintained?

List 4 faults associated with poor handling of film during processing.

List 2 faults associated with the mishandling of x-ray cassettes.

What is dichroic fog?

What colour will developer and fixer splashes appear on an exposed film?

List 4 common environmental problems associated with processing.

List 4 advantages of automatic processing over manual development.

List 4 factors that may cause a radiograph to appear too dark.

List 4 factors that may cause a radiograph to appear too pale.

What are the 3 key terms used in the assessment of radiographic quality?

Under-development is the most common processing fault. How might this be prevented?

What is meant by a "soot and whitewash" film?

What is meant by a "flat" film?

Positioning & Collimation - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 06:39:46 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:39:46

In addition to setting up equipment for radiography, you will almost certainly be asked to position a patient for one or more radiographic examination. The table shows parts of the anatomy that you should be familiar with, the position of the patient and the area to which collimation is made.

In all cases, the following points are essential:

Read the question carefully before attempting the task.

If the patient is conscious, ask an assistant to restrain and reassure before gathering together the necessary equipment (even if it is a soft toy).

Collect together the equipment as demonstrated in Practical Tasks: Equipment For Radiography. Make use of positioning aids available including troughs, foam wedges, ties and sandbags.

An animal with dyspnoea or any condition where pleural effusion is suspected must never be placed in dorsal recumbency (VD position).

Barium should never be given per os (by mouth) to a patient with dysphagia since aspiration pneumonia is likely to be a risk.

It is advisable to take at least 2 views of any radiograph to enable improved radiographic interpretation. A hairy dog with a small metal object such as a pin or paper clip entangled in its coat may well look like the object has been ingested; a lateral and ventral view would rule out this condition. It is unlikely that your practical task will involve multiple projections, but this is an important point to remember.

Limbs must be positioned 90 degrees to the primary beam and parallel with the cassette to avoid anatomical distortion.

Collimate the beam to as small an area as possible to create good contrast avoiding scattered radiation.

The thorax is best radiographed on inspiration to enable a better view of the lung fields; whilst the abdomen is best radiographed on expiration in order to enable better visualisation of the viscera.

When performing radiography of the joints and spine, accurate centring is essential to avoid geometric distortion.

Use a grid when radiography of a part of the patient's anatomy exceeds a thickness of 10cm.

Finally, and most importantly; ensure that you are familiar with the anatomical directions used in radiographic positioning. You will need to demonstrate your knowledge of these in the practical examination. It is also advisable to revise your Part I anatomy and physiology notes to ensure that you are competent naming and identifying parts of the patient's anatomy; particularly those of the skeletal system.

Chart For Positioning & Collimation - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 06:38:18 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:38:18

Anatomy Positioning Aids Collimation Notes

Lateral Skull

Lateral recumbency

Foam wedges beneath muzzle to ensure that head is parallel to table; pad neck & sternum to stabilise.

Collimation depends upon the point of interest; possible areas include: cranium, zygomatic arch, mandibles, frontal sinuses, nasal turbinates, tympanic bullae & teeth.

The centering point depends upon the area of interest; the head may be tilted upwards for an improved view of the temporo-mandibular joints.

DV. Skull

Ventral recumbency

Muzzle positioned flat to the cassette; a sandbag over the neck secures the head in place.

Midline structures; ie. the frontal bone, frontal sinuses or maxillae.

Raising the cassette on a wooden block may aid positioning.

VD. Skull

Dorsal recumbency

Use trough to support VD position; foam pads will support the nose and neck, while tapes secured behind the upper canines hold the muzzle close to the plate.

Mandibles and tympanic bullae.

The head and neck must be extended; an open-mouthed oblique view variation on this position is suitable for radiographs of the nasal sinuses.

Oblique Skull

Lateral recumbency

The head is positioned within a trough to enable the skull to be angled correctly.

Tympanic bullae and temporo-mandibular joints.

The skull should be rotated 20 degrees around its long axis towards the VD position.

R.Ca. Skull (Rostro-caudal)

Dorsal recumbency (with neck flexed to 90 degrees)

Use trough to support VD position; tapes behind the upper and lower canines to hold open the jaws for radiographs of the tympanic bullae.

Tympanic bullae (mouth open) and frontal sinuses (mouth closed).

Ensure that the back of the head and the neck are flat to the table.

Intra-oral DV Occlusal Skull

Sternal recumbency

Rest the chin on a wooden or foam block to ensure that the head is level; a sandbag over the neck supports the position.

Nasal chambers.

A general anaesthetic is essential for this view; non-screen film is used meaning that a longer exposure time will be necessary.

Lateral Thorax (chest)

Lateral recumbency; right lateral for heart radiographs as a more consistent outline is achieved; left and right lateral for the lungs as the upper most lungfield is better aerated.

Use sandbags to bring forward the forelimbs and hold back the hindlimbs; a foam pad raises the sternum to the same height above the tabletop as the spine.

Collimate level with the 5th rib and the caudal border of the scapula.

Chest radiographs should be taken on inspiration since a superior view of the lungfields is provided.

DV. Thorax

Ventral recumbency

Draw forward the forelimbs to prevent them from obscuring the cranial thorax; a sandbag over the neck aids positioning; foam pads either side of the sternum offer support.

The centering point is between the scapulae. Collimate to ensure that the lungfields are included.

This is a good position for cardiac radiography since the VD view may cause the heart to tip to one side.

VD. Thorax

Dorsal recumbency

Use a trough to ensure that the patient is straight; draw the forelimbs well forwards with ties or sandbags.

Centre on the midpoint of the sternum.

Never use this position if the patient is dyspnoeic.

Lateral Abdomen

Lateral recumbency

Use sandbags or ties to bring forward the forelimbs; in addition the hindlimbs must be well drawn back to prevent them from obscuring the caudal abdomen; a foam wedge underneath the abdomen ensures that a straight position is achieved.

Collimate to include areas of interest such as the liver, spleen or intestines. The view may be of caudal abdomen to include the bladder.

Abdominal views are taken on expiration since this provides a more spread out view (and subsequently better visualisation) of the viscera.

VD. Abdomen

Dorsal recumbency

The patient is best supported in a trough; both fore and hind limbs should be tied to prevent them from obscuring the view.

Collimate to include areas of interest such as the liver, spleen or intestines.

Never use this position if the patient is dyspnoeic (the DV view is rarely used for abdominal radiographs since this causes compression and distortion of the viscera).

Lateral Spine

Lateral recumbency (usually right sided)

Foam padding is required beneath the chest, behind the head and between the limbs since it is essential that the spine is parallel to the table and not subject to sagging or rotation.

Collimate to include the vertebrae of interest:
Cervical C1-C6, Cervico-thoracic C6-T3, Thoracic T3-T11, Thoraco-lumbar T11-L3, Lumbar L1-L7, Sacro-coccygeal L6-Cd4; centre upon L4-L5 or L5-L6 for myelography.

Spinal radiographs are carried out in a survey format since it is impossible to attain an accurate picture of the entire spine due to the divergence of the primary beam; this means that disc spaces not centred will be obscured by the shadows of adjacent vertebrae.

VD. Spine

Dorsal recumbency

Position the patient within a trough; ensure that the spine is straight by making use of foam wedges, ties and sandbags.

Collimate to include C1-C6 or C6-T3.

For radiographs of the cervical spine or thoracic junction, the x-ray beam is angled 15-20 degrees towards the patient's head.

Lateral Scapula

Lateral recumbency, affected side down.

The lower limb is drawn back and secured with a sandbag; the upper limb is secured with a tie towards the head.

Collimate to include the lower scapula; this is the shoulder blade (palpated above the humerus).

Take care to ensure that the limbs do not obscure the image.

Cd.Cr. Scapula

Dorsal recumbency

The forelimb of the affected side is drawn forwards and held in maximum extension with a tie.

Collimate to include the lower scapula.

Tilting the animal slightly over to the contra lateral side will aid positioning.

Lateral Shoulder

Lateral recumbency, affected side down.

The lower limb is drawn forwards and secured with a tie; the upper limb is pulled back.

Centre on the shoulder joint where the distal scapula meets the proximal humerus.

The head and neck should be extended.

Cd.Cr. Shoulder

Dorsal recumbency

The patient is supported within a trough; the forelimb is drawn forwards and held in maximum extension with a tie.

Centre on the shoulder joint where the distal scapula meets the proximal humerus.

Tilt the animal slightly over to the contra lateral side.

Lateral Elbow

Lateral recumbency, affected side down.

The lower limb is drawn forwards and secured with a tie; the upper limb is drawn backwards and tied or held in position with a sandbag.

Centre on the elbow joint where the distal humerus joins the proximal radius and ulna; the anconeal process (proximal notch or coronoid process (distal notch) may be points of interest.

A flexed view of the lateral elbow is useful for the assessment of degenerative joint disease.

Cd.Cr. Elbow

Dorsal recumbency

The patient is supported within a trough; affected limb is drawn towards the head and secured in maximum extension with a tie.

Centre on the elbow joint where distal humerus meets proximal radius and ulna.

Tip the patient slightly towards the contra lateral side to achieve a better view.

Cr.Cd. Elbow

Ventral or sternal recumbency.

Support the patient on either side with sandbags or foam wedges; both forelimbs are extended caudally and tied into position.

Centre on the elbow joint where distal humerus meets proximal radius and ulna.

The x-ray beam should be angled 10-15 degrees towards the tail; another Cr.Cd. technique is to position the patient in dorsal recumbency with the caudal aspect of the affected limb placed flat to the x-ray cassette (the paw is directed towards the tail).

Lateral Humerus

Lateral recumbency; affected side down.

The neck is secured in position with a sandbag; the affected limb is extended and tied whilst the non-affected (upper) forelimb is pulled back out of the way and held with a sandbag or tie.

Collimate to include the humerus (the long bone between the shoulder and elbow joints).

Cd.Cr. Humerus

Dorsal recumbency

The patient is supported with a trough; the affected limb is extended cranially and tied into place.

Collimate to include the humerus (the long bone between the shoulder and elbow joints).

As with positioning for radiography of the scapula and shoulder joint - tip the patient slightly over to the side not under investigation. Note: long object film distance unavoidable.

Cr.Cd. Humerus

Dorsal recumbency

The patient is supported within a trough with the affected limb extended caudally and tied into position.

Collimate to include the humerus (the long bone between the elbow and shoulder joints).

The humerus should lie parallel to the cassette which is not always possible if a trough is used; substitute the trough for sandbags and foam wedges if necessary.

Lateral Radius & Ulna

Lateral recumbency; affected side down.

The affected (lower) limb is drawn forwards and tied; the non-affected (upper) limb is drawn backwards out of the way and held with a tie or sandbag.

Collimate to include the radius and ulna = the 2 forearm bones; the radius articulates proximally with the humerus at the elbow joint and distally with the carpus; the olecranon (proximal ulna) forms the point of the elbow.

Positioning may be aided with the use of radiolucent sticky tape.

Cr.Cd. Radius & Ulna

Sternal recumbency

The patient is supported with sandbags or foam wedges; the affected limb is extended cranially and held in position with a tie.

Collimate to include the radius and ulna = the 2 forearm bones.

Ensure that the patient's head does not obscure the view of the desired area of collimation.

Lateral carpus and paw

Lateral recumbency affected side down.

The affected limb is extended cranially and tied into position whilst the lower limb is drawn back out of the way and held with a tie or sandbag.

Centre on the carpus (wrist joint), carpal bones or metacarpals as desired.

For radiography of individual digits, separate the toes bringing forward that to be x-rayed and holding back the rest with radiolucent sticky tape.

D.Pa. Carpus & Paw

Sternal recumbency

The forelimbs are extended cranially and tied or taped into position; the head is tilted over to the non-affected side and held out of the way with a sandbag.

Centre on the carpus (wrist), carpal bones or metacarpals as desired.

Digits may also be radiographed and separated for better definition with sticky tape.

Lateral Pelvis

Lateral recumbency

Foam padding is placed underneath the spine and sternum and also between the stifles to ensure a true lateral view.

Collimate to include the hip joint/s where the pelvis meets the proximal humerus.

If one limb only is affected, this may be placed laterally upon the cassette with the non-affected limb flexed backwards out of the way; an angled beam is required for this view.

VD. Pelvis

Dorsal recumbency

The patient is positioned within a trough; the forelimbs are secured cranially and a sandbag is draped over the sternum to ensure that the patient is straight; the stifles are rotated inwards and taped; the hind limbs are extended caudally and tied.

Collimate to include both hip joints, centering on the pubic symphysis.

This position is required for the Kennel Club/BVA Hip Dysplasia scheme; the flexed or "frog-legged" view where the hind limbs are not tied and left to fall either side of the pelvis is suitable in trauma cases where manipulation may prove painful.

Lateral Femur

Lateral recumbency; affected side down.

The lower limb is placed on the cassette with the upper limb flexed and tied vertically up out of the way; a pad beneath the hock ensures a true lateral position.

Collimate to the include femur; the long bone which runs between the hip and stifle joints.

The lower femur may be radiographed through the abdomen to prevent super-imposition of the upper limb.

Cr.Cd. Femur

Dorsal recumbency

The patient is positioned within a trough with the forelimbs secured cranially; the affected hind limb is extended caudally and tied or taped into place.

Collimate to include the femur; the long bone which runs between the hip and stifle joints.

Lateral Stifle

Lateral recumbency; affected side down.

The affected stifle is positioned laterally on the cassette; a pad beneath the hock ensures a true lateral view; the non-affected limb is tied vertically or caudally out of view.

Collimate to include the stifle joint (the knee); this is the joint sited between the distal femur and the proximal tibia and fibula.

Obese patients may benefit from a compression band to prevent super-imposition of mammary tissue or the sheath; the lateral stifle may also be radiographed with a horizontal beam.

Cd.Cr. Stifle

Sternal recumbency

The patient is supported with sandbags or foam wedges; the affected limb is extended caudally and tied or taped into place; a large sandbag draped across the rump will help to keep the animal straight.

Collimate to include the stifle joint (the knee); this is the joint sited between the distal femur and the proximal tibia and fibula.

Cr.Cd. Stifle

Dorsal recumbency

The patient is supported within a trough; the affected limb is extended and tied or taped into place; the non-affected limb may be left free.

Collimate to include the stifle joint (the knee); this is the joint sited between the distal femur and the proximal tibia and fibula.

Tilting the patient slightly away from the affected side may aid positioning and ensure a true cranio-caudal view.

Lateral Hock, Tibia & Paw

Lateral recumbency; affected side down.

The affected limb is positioned on the cassette with tapes or ties; the upper limb is drawn either forwards or backwards out of view and secured with ties or sandbags.

Centre on the hock joint - where the distal tibia and fibula meet the proximal metatarsals, the tibia/fibula - the long bones running between the hock and stifle or the paw.

For radiography of the paw, separate the digits for better definition.

Cr.Cd. Tibia

Ventral recumbency

The patient is supported within a trough with the affected limb extended and tied into place.

Centre on the tibia; the long bone running between the hock and stifle.

D.Pl. Hock

Ventral recumbency

The patient is supported within a trough with the affected limb extended and tied into place.

Centre on the hock joint where the distal tibia and fibula meet the proximal metatarsals.

Tape may be looped around the paw to aid positioning; it may be necessary to raise the cassette in order to decrease the object-film distance with this view.

D.Pl. Paw

Ventral recumbency

The patient is supported within a trough with the affected limb extended caudally and tied into place; separate the digits if desired.

Collimate to include the digit/s.

Strong, radiolucent, adhesive tape may be necessary to hold the paw in the desired position on the cassette

Anatomical Directions - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 06:23:45 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:23:45

DIRECTION OR POSITION EXPLANATION

Caudal Towards the tail. Never used in lower limb descriptions.

Caudo-cranial (Cd.Cr) Tail to head (rear to front).

Cranial Towards the head. Never used in lower limb descriptions. Nor when describing the head - oral or rostral are correct.

Cranio-caudal (Cr.Cd) Head to tail (front to rear).

Distal Away from the body; a term used in limb descriptions.

Dorsal Term relating to the back or posterior part of an animal. A patient in dorsal recumbency is lying on its back.

Dorso-palmar (D.Pa) Describes view of the lower fore limb (beyond the radiocarpal joint); front of lower limb to rear of lower limb, ie. the lower forelimb is placed palmar side down on the x-ray cassette.

Dorso-plantar (D.Pl) Describes view of the lower hind limb (beyond the tibiotarsal joint); front of lower limb to rear of lower limb, ie. the lower hind limb is placed plantar side down on the x-ray cassette.

Dorso-ventral (DV) Back to front. A patient positioned for DV x-rays will be lying abdomen face down; ie. in ventral recumbency.

Extended view Describes a joint in extension; ie. distal limb directed away from the body.

Flexed view Describes a joint in flexion; ie. distal limb directed towards the body.

Frog legged view The patient lies in dorsal recumbency (VD position) with the hind limbs flexed and allowed to fall to either side. This view may be used to radiograph the pelvis although it is not as diagnostic as an extended view.

Intra oral view Within the oral cavity. Non-screen film may be placed within the mouth in order to radiograph the jaws, nasal chambers or teeth.

Lateral Sideways; an animal in lateral recumbency will be lying on its side. (Right lateral recumbency means that the right side is down on the table).

Oblique view An angled view. The skull may be positioned obliquely in order to obtain good radiographs of the tympanic bullae and temporo-mandibular joints.

Occlusal view A closed view; usually refers to closed mouth intra-oral radiographs.

Palmar The rear of the lower forelimb.

Palmaro-dorsal (Pa.D) Back to front; referring to the forelimb beyond the radiocarpal joint.

Plantar The rear of the lower hindlimb.

Plantaro-dorsal (Pl.D) Back to front; referring to the hindlimb beyond the tibiotarsal joint.

Posterior-anterior (PA) Bottom up.

Proximal Directed towards the body; a term used in limb descriptions.

Rostral Directed towards the nose.

Rostro-caudal (R.Ca) Nose to tail. A rostro-caudal view (with the patient's head positioned nose upwards and the back of the head on the xray cassette) is suitable for radiography of the frontal sinuses.

Sternal Term relating to the chest; a patient in sternal recumbency will be lying chest down.

Supine Lying on the back; ie. dorsal recumbency.

Ventral Term relating to the abdomen; a patient in ventral recumbency will be lying on its abdomen.

Ventro-dorsal (VD) Abdomen to back; ie. front to back.

Radiographic Settings Intro - Key Notes

Arlo Guthrie — Tue, 21 Apr 2009 06:21:59 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:21:59

The exposures required to take good quality, diagnostic radiographs depend upon many factors including the type of x-ray machine, the processor and of course the patient. It is for this reason that veterinary practices should keep a log of all radiographs taken comprising as much information as possible and accurate reports of the quality of the resultant exposed films. This will aid personnel in that a useful exposure chart can be created to allow quick reference to the settings required for any part of the anatomy of as many species and breeds as possible. In addition, film speed is relevant; medium speed is the best compromise. Slow film/screen combinations produce the highest definition suitable for small areas such as the limbs and skull. A fast film-screen combination requires lower exposures than a slow film-screen combination, but produces less definition than the latter.

EXPOSURE LOG
The following should be noted:

Date.

Owner's name and patient identification.

Species & breed.

Size & weight (note whether the animal is obese, under-weight, juvenile, pregnant etc).

Part of the patient's anatomy radiographed.

Position of the patient.

Film/screen combination.

Film focal distance.

Type of grid used if applicable (used for tissue depths of 10cm or greater).

Exposure settings used (kV, mA, mAs).

Notes, eg. quality of resultant film, plaster cast present, contrast agents used.

LINE VOLTAGE
A line voltage compensator may be found in lower output x-ray machines. This is used to control fluctuations in the mains electricity that may result in inconsistent output of x-rays despite normal exposure factors. Line voltage should only be adjusted if indicated, and must never be used to directly alter other exposure factors.
Larger x-ray machines are likely to possess an autotransformer which automatically controls mains voltage fluctuations.

KILOVOLTAGE (kV)
Kilovoltage is commonly shortened to kV. It is the kV control that affects the energy of the x-ray photons and thus affects both contrast and blackening of the image. kV is defined as the potential difference applied between the filament (cathode) and target (anode) of the x-ray tube head. The subsequent speed and energy with which the electrons bombard the target affects the penetrating power of the primary beam. The kV control may be directly linked to the milliamperage (mA) control in smaller machines. This means that mA is lowered as kV is raised, which is not ideal in circumstances where both a high mA and kV are required (such as in large patients) since longer exposure times are therefore necessary.
If the kV is increased by 10, the mAs should be halved to achieve the same exposure and if kV is decreased by 10, the mAs should be doubled.

MILLIAMPERAGE (mA)
Milliamperage is commonly shortened to mA. The mA setting will affect the quantity of electrons passing across the x-ray tube head from the filament to the target and has an effect only upon the blackening of the image. mA is also referred to as the tube current. Since the current is so small, it is measured in milliamperes rather than amperes. Raising the mA causes the filament to increase in heat subsequently causing the release of more electrons.

MILLIAMPERE SECONDS (mAs)
mAs is the measurement of the length of exposure time. The longer the exposure time, the more likely you are to encounter movement blur. If the mA (tube current) is increased, the exposure time is lowered. It is sensible therefore to use the highest mA possible. A higher kV also allows the mAs to be kept small.
mAs should be doubled to penetrate a dry plaster cast, and doubled again to penetrate a wet plaster cast.
Some useful x-rays are absorbed by grids, which means that if a grid is used, mAs must be increased; multiply the mAs required without a grid by the grid factor.

THE EXAMINATION
When calculating exposures, always remember that:

EXPOSURE TIME (in seconds) = mAs divided by mA.
NB. 15 mAs = 150 mA for 0.1 sec OR 15 mA for 1.0 sec.

Since all x-ray machines require different exposures, it is unlikely that you will be required to state settings in the practical examination. You will however encounter written questions necessitating a good working knowledge of the formula involved.

The example questions below are similar to those that have appeared in the written papers and should be of help to you during revision:

1) Which of the following radiographic settings will produce an image with the greatest density?

a) 100 mA, 0.1 sec.
b) 150 mA, 0.05 sec.
c) 200 mA, 0.05 sec.
d) 200mA, 0.1 sec.
The answer is d) since these settings produce the greatest tube current for the longest time period.

2) A radiograph is to be taken of a patient post casting (the cast is still wet). How would you adjust normal exposure factors in order to obtain a good quality image?

a) Increase kV by 10 and double the mAs.
b) Decrease kV by 10 and double the mAs.
c) Halve the mAs only.
d) Double the mAs only.

The answer is a) since increasing the kV by 10 means that an equivalent exposure would be achieved by reducing the mAs by half; we require a greater exposure and therefore instead of reducing the mAs we double it. Thus the effect of twice doubling the mAs is achieved.

3) If a radiographic exposure is given as 60 kV and 15 mAs, what would the exposure time be if the output of the machine is 10 mA?

a) 15 secs.
b) 0.15 sec.
c) 1.5 secs.
d) 2 secs.

The answer is c). kV is not relevant to this question; exposure time = mAs divided by mA (15 divided by 10 is 1.5).

4) If a radiographic exposure is given as 70 kV and 10 mAs and the output of the machine is 10 mA, what would the exposure be if a grid with a grid factor of 2 were used?

a) 20 mAs.
b) 70 mAs.
c) 15 mAs.
d) 20 mAs.

The answer is a) since the original mAs is multiplied by the grid factor (10 x 2 =20).

5) The settings are as per Q4; what would the exposure be if the kV was raised to 80 and no grid was used?

a) 20 mAs.
b) 12 mAs.
c) 2 mAs.
d) 5 mAs.

The answer is d) since mAs is halved for every 10 kV increase (10 divided by 2 = 5).

6) Again, the settings are as per Q4; what would the exposure be if the kV was lowered to 60 and no grid was used?

a) 5 mAs.
b) 20 mAs.
c) 15 mAs.
d) 2.0 mAs.

The answer is b), mAs is doubled for every 10 kV decrease (10 x 2 = 20)

Settings, Positioning, Collimating & Centring - Answers

Arlo Guthrie — Tue, 21 Apr 2009 06:18:31 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:18:31

ANSWERS

List the details required for an exposure chart.

Part of the anatomy radiographed.

Positioning of the patient.

Film-screen combination.

FFD.

Type of grid used (if applicable).

Kilovoltage (kV).

Tube current (mA).

Milliampere seconds (mAs).

What are the preferred techniques for the labelling of radiographs?

Lead letters.

Perspex tablets.

Lead tape.
NB. All above are primary labelling ie. put on before processing.

Why are the answers to Q2 preferable to chinagraph pencil or light markers?
They are all permanent, unlike chinagraph pencil (secondary labelling, after processing) or light markers.

What information must be present on a BVA KC hip dysplasia scoring scheme radiograph?

Kennel club reference number.

Date.

Left or right marker.

List 6 positioning aids used in radiography.

Foam blocks and wedges in a variety of sizes.

Sandbags.

Ties.

Sticky tape.

Troughs.

Wooden blocks.

Whilst cranio-caudal (Cr.Cd) and caudo-cranial (Cd.Cr) are used to describe radiographic views above the radiocarpal and tibiotarsal joints, what nomenclature describes the views below these joints?

Dorso-palmar (D.Pa) or palmaro-dorsal (Pa.D) for a forelimb.

Dorso-plantar (D.Pl) or plantaro-dorsal (Pl.D) for a hindlimb.

Why are thoracic radiographs usually taken on inspiration?
To enable a better view of the lung fields.

What positions are suitable for heart radiographs and why?

Right lateral recumbency - heart outline is more consistent in shape.

Ventral or sternal recumbency - avoids tipping the heart to one side (as in dorsal recumbency).

Why are abdominal radiographs usually taken on expiration?
To enable a more spread out view and thus better visualisation of the viscera.

Why must a dyspnoeic patient not be placed in dorsal recumbency (ventro-dorsal position)?
Any condition where pleural effusion is suspected can be worsened to such a degree that this may result in the death of the patient. Pneumothorax and ruptured diaphragm are examples. Always take special care in RTA and shock cases.

In spinal radiography, why is it preferable to perform a series of x-rays rather than simply one view of the vertebral column?
The divergence of the x-ray beam means that shadows will be cast upon the disc spaces by adjacent vertebrae. A spinal survey will help to prevent this, and thus reduces the possibility of vital information being missed.

What position is required for the BVA KC Hip Dysplasia Scheme?
Ventro-dorsal with extended hips. The beam is centred on the pubic symphysis.

When would it be advisable to use the flexed (or "frog-legged") view of the pelvis?
In traumatised patients where manipulation of the hips or pelvis may prove painful, or in cases of suspected fracture where manipulation could cause displacement.

Settings, Positioning, Collimating & Centring

Arlo Guthrie — Tue, 21 Apr 2009 06:17:32 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:17:32

QUESTIONS

List the details required for an exposure chart.

What are the preferred techniques for the labelling of radiographs?

Why are the answers to Q2 preferable to chinagraph pencil or light markers?

What information must be present on a BVA KC hip dysplasia scoring scheme radiograph?

List 6 positioning aids used in radiography.

Whilst cranio-caudal (Cr.Cd) and caudo-cranial (Cd.Cr) are used to describe radiographic views above the radiocarpal and tibiotarsal joints, what nomenclature describes the views below these joints?

Why are thoracic radiographs usually taken on inspiration?

What positions are suitable for heart radiographs and why?

Why are abdominal radiographs usually taken on expiration?

Why must a dyspnoeic patient not be placed in dorsal recumbency (ventro-dorsal position)?

In spinal radiography, why is it preferable to perform a series of x-rays rather than simply one view of the vertebral column?

What position is required for the BVA KC Hip Dysplasia Scheme?

When would it be advisable to use the flexed (or "frog-legged") view of the pelvis?

Preparing Radiography Equipment - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 06:15:16 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:15:16

Preparing Radiography Equipment - Practical Task

INTRODUCTION
Preparation of radiographic equipment is a favourite in the practical examination. The format of the task is usually to position a patient for radiographic examination of a named part of the anatomy (see Practical Tasks: Positioning). The equipment should be gathered together and correctly set up prior to positioning. Since x-rays are hazardous, safety is of paramount importance both in the exam and in practice. It is therefore vital to familiarise yourself with all the equipment that may be necessary and be able to identify any faults to avoid taking radiographs of poor diagnostic quality. Efficient organisation and preparation will reduce the time taken in radiography, and will subsequently lower the duration of sedation or anaesthesia of the patient.

THE PROCESSOR

Is the processor at the correct temperature; ie. 20°C for manual processing or 28°C for automatic processing?

Is the darkroom clean, dry and well organised with sufficient supplies of radiographic film of the correct film-screen combination?

If the answer to these questions is yes, it is safe to go ahead with the necessary radiographic procedures. If the answer is no; the processed films may be poorly developed and non-diagnostic. It cannot be stressed enough that repeated, unnecessary exposures are hazardous to both the patient and the radiographer; and therefore all steps must be taken to ensure that avoidable problems are not encountered.

THE CONTROLLED AREA
Are the following displayed?

Red warning light at access points.

Radiation warning symbol at access points.

Local rules

All personnel involved in radiography should have read and understood The Ionising Radiations Regulations 1999, The Approved Code of Practice for the Protection of Persons Against Ionising Radiation Arising from any Work Activity and The Guidance Notes for the Protection of Persons Against Ionising Radiations Arising from Veterinary Use 1988.

THE X-RAY MACHINE
Always check the following:

Collimation device/light beam diaphragm alignment.

Aluminium filter.

Line voltage.

Service records.

PERSONAL SAFETY
The following should be available and always be used:

Lead aprons.

Lead gloves.

Lead sleeves.

Personal dosemeter.

Lead-lined table or lead sheeting to be place beneath x-ray cassette.

Lead-lined wall (if this is not feasible, a lead screen may be used).

Aluminium filter incorporated into the x-ray machine (this is required by law).

Collimation device (light beam diaphragm is far preferable to a cone).

Exposure button allowing the operator to stand at least 2m away from the primary beam (ideally the operator should be able to stand outside the room in which x-rays are taken).

Grids for exposures of body tissues 10cm thick or deeper.

Compression bands to apply to large areas of body tissue.

CASSETTE
This should contain a film of the correct film-screen combination, be of a suitable size for the radiographic views required, possess clean intensifying screens and be impermeable to visible light. Some cassettes are designed to hold a stationary grid (which should be positioned between the cassette and the patient).
If non-screen films are used, these should be clean and dry and contained within a light proof envelope. Non-screen film must be placed a certain side up within its envelope.

POSITIONING AIDS
The following may be useful (refer to Practical Task: Positioning for further details):

Radiolucent troughs.

Sandbags.

Ties.

Foam wedges.

Wooden blocks

OTHER EQUIPMENT

Marking devices; lead letters or lead tape are best.

Lead sheeting to protect parts of the patient not radiographed (also the film if only part used in one exposure).

THE PATIENT
Having established all the previously mentioned criteria; only then is it prudent to sedate or anaesthetise the patient for radiography. The following points are critical:

Sedation or anaesthesia are essential unless contra-indicated; manual holding is to be avoided if at all possible.

Ensure that endotracheal tubes, an anaesthetic machine and all the necessary anaesthetic equipment are on hand in the controlled area.

Emergency resuscitation equipment should also be available.

An assistant should be present to monitor the sedated or anaesthetised patient during the radiographic procedure

CHECK-LIST FOR THE PRACTICAL EXAMINATION

Start from the bottom upwards….

Lead sheeting; put in place even if the table is lead lined - double thickness is better.

Cassette.

Marker - Left or right marker plus date and patient identification; this should be in lead or perspex letters or inscribed on lead impregnated tape.

Grid; ensure that this is the correct way up (a grid ratio of 8:1 is suitable). The Potter Bucky moving grid incorporated into the table top is by far the best, but failing this a focused or pseudo-focused grid is acceptable (parallel grids may cause "grid cut-off"). The grid should be situated between the cassette and the patient.

Positioning aids - choose those relevant to the view required.

Finally, having established all other factors, position the patient (refer to Practical Task: Positioning).

Ensure that you are able to state the point of collimation of the primary beam.

Be aware of any potential hazards associated with radiography and be able to state these to the examiner (read this chapter fully and refer to regulations stated in Q1).

Preparing Radiography Equipment - Practical Task

Arlo Guthrie — Tue, 21 Apr 2009 06:14:48 GMT
Revision 2 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:14:48

Preparing Radiography Equipment - Practical Task

INTRODUCTION
Preparation of radiographic equipment is a favourite in the practical examination. The format of the task is usually to position a patient for radiographic examination of a named part of the anatomy (see Practical Tasks: Positioning). The equipment should be gathered together and correctly set up prior to positioning. Since x-rays are hazardous, safety is of paramount importance both in the exam and in practice. It is therefore vital to familiarise yourself with all the equipment that may be necessary and be able to identify any faults to avoid taking radiographs of poor diagnostic quality. Efficient organisation and preparation will reduce the time taken in radiography, and will subsequently lower the duration of sedation or anaesthesia of the patient.

THE PROCESSOR

Is the processor at the correct temperature; ie. 20°C for manual processing or 28°C for automatic processing?

Is the darkroom clean, dry and well organised with sufficient supplies of radiographic film of the correct film-screen combination?

If the answer to these questions is yes, it is safe to go ahead with the necessary radiographic procedures. If the answer is no; the processed films may be poorly developed and non-diagnostic. It cannot be stressed enough that repeated, unnecessary exposures are hazardous to both the patient and the radiographer; and therefore all steps must be taken to ensure that avoidable problems are not encountered.

THE CONTROLLED AREA
Are the following displayed?

Red warning light at access points.

Radiation warning symbol at access points.

Local rules

All personnel involved in radiography should have read and understood The Ionising Radiations Regulations 1999, The Approved Code of Practice for the Protection of Persons Against Ionising Radiation Arising from any Work Activity and The Guidance Notes for the Protection of Persons Against Ionising Radiations Arising from Veterinary Use 1988.

THE X-RAY MACHINE
Always check the following:

Collimation device/light beam diaphragm alignment.

Aluminium filter.

Line voltage.

Service records.

PERSONAL SAFETY
The following should be available and always be used:

Lead aprons.

Lead gloves.

Lead sleeves.

Personal dosemeter.

Lead-lined table or lead sheeting to be place beneath x-ray cassette.

Lead-lined wall (if this is not feasible, a lead screen may be used).

Aluminium filter incorporated into the x-ray machine (this is required by law).

Collimation device (light beam diaphragm is far preferable to a cone).

Exposure button allowing the operator to stand at least 2m away from the primary beam (ideally the operator should be able to stand outside the room in which x-rays are taken).

Grids for exposures of body tissues 10cm thick or deeper.

Compression bands to apply to large areas of body tissue.

CASSETTE
This should contain a film of the correct film-screen combination, be of a suitable size for the radiographic views required, possess clean intensifying screens and be impermeable to visible light. Some cassettes are designed to hold a stationary grid (which should be positioned between the cassette and the patient).
If non-screen films are used, these should be clean and dry and contained within a light proof envelope. Non-screen film must be placed a certain side up within its envelope.

POSITIONING AIDS
The following may be useful (refer to Practical Task: Positioning for further details):

Radiolucent troughs.

Sandbags.

Ties.

Foam wedges.

Wooden blocks

OTHER EQUIPMENT

Marking devices; lead letters or lead tape are best.

Lead sheeting to protect parts of the patient not radiographed (also the film if only part used in one exposure).

THE PATIENT
Having established all the previously mentioned criteria; only then is it prudent to sedate or anaesthetise the patient for radiography. The following points are critical:

Sedation or anaesthesia are essential unless contra-indicated; manual holding is to be avoided if at all possible.

Ensure that endotracheal tubes, an anaesthetic machine and all the necessary anaesthetic equipment are on hand in the controlled area.

Emergency resuscitation equipment should also be available.

An assistant should be present to monitor the sedated or anaesthetised patient during the radiographic procedure

CHECK-LIST FOR THE PRACTICAL EXAMINATION

Start from the bottom upwards….

Lead sheeting; put in place even if the table is lead lined - double thickness is better.

Cassette.

Marker - Left or right marker plus date and patient identification; this should be in lead or perspex letters or inscribed on lead impregnated tape.

Grid; ensure that this is the correct way up (a grid ratio of 8:1 is suitable). The Potter Bucky moving grid incorporated into the table top is by far the best, but failing this a focused or pseudo-focused grid is acceptable (parallel grids may cause "grid cut-off"). The grid should be situated between the cassette and the patient.

Positioning aids - choose those relevant to the view required.

Finally, having established all other factors, position the patient (refer to Practical Task: Positioning).

Ensure that you are able to state the point of collimation of the primary beam.

Be aware of any potential hazards associated with radiography and be able to state these to the examiner (read this chapter fully and refer to regulations stated in Q1).

Preparing Radiography Equipment

Arlo Guthrie — Tue, 21 Apr 2009 06:14:34 GMT
Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:14:34

INTRODUCTION
Preparation of radiographic equipment is a favourite in the practical examination. The format of the task is usually to position a patient for radiographic examination of a named part of the anatomy (see Practical Tasks: Positioning). The equipment should be gathered together and correctly set up prior to positioning. Since x-rays are hazardous, safety is of paramount importance both in the exam and in practice. It is therefore vital to familiarise yourself with all the equipment that may be necessary and be able to identify any faults to avoid taking radiographs of poor diagnostic quality. Efficient organisation and preparation will reduce the time taken in radiography, and will subsequently lower the duration of sedation or anaesthesia of the patient.

THE PROCESSOR

Is the processor at the correct temperature; ie. 20°C for manual processing or 28°C for automatic processing?

Is the darkroom clean, dry and well organised with sufficient supplies of radiographic film of the correct film-screen combination?

If the answer to these questions is yes, it is safe to go ahead with the necessary radiographic procedures. If the answer is no; the processed films may be poorly developed and non-diagnostic. It cannot be stressed enough that repeated, unnecessary exposures are hazardous to both the patient and the radiographer; and therefore all steps must be taken to ensure that avoidable problems are not encountered.

THE CONTROLLED AREA
Are the following displayed?

Red warning light at access points.

Radiation warning symbol at access points.

Local rules

All personnel involved in radiography should have read and understood The Ionising Radiations Regulations 1999, The Approved Code of Practice for the Protection of Persons Against Ionising Radiation Arising from any Work Activity and The Guidance Notes for the Protection of Persons Against Ionising Radiations Arising from Veterinary Use 1988.

THE X-RAY MACHINE
Always check the following:

Collimation device/light beam diaphragm alignment.

Aluminium filter.

Line voltage.

Service records.

PERSONAL SAFETY
The following should be available and always be used:

Lead aprons.

Lead gloves.

Lead sleeves.

Personal dosemeter.

Lead-lined table or lead sheeting to be place beneath x-ray cassette.

Lead-lined wall (if this is not feasible, a lead screen may be used).

Aluminium filter incorporated into the x-ray machine (this is required by law).

Collimation device (light beam diaphragm is far preferable to a cone).

Exposure button allowing the operator to stand at least 2m away from the primary beam (ideally the operator should be able to stand outside the room in which x-rays are taken).

Grids for exposures of body tissues 10cm thick or deeper.

Compression bands to apply to large areas of body tissue.

CASSETTE
This should contain a film of the correct film-screen combination, be of a suitable size for the radiographic views required, possess clean intensifying screens and be impermeable to visible light. Some cassettes are designed to hold a stationary grid (which should be positioned between the cassette and the patient).
If non-screen films are used, these should be clean and dry and contained within a light proof envelope. Non-screen film must be placed a certain side up within its envelope.

POSITIONING AIDS
The following may be useful (refer to Practical Task: Positioning for further details):

Radiolucent troughs.

Sandbags.

Ties.

Foam wedges.

Wooden blocks

OTHER EQUIPMENT

Marking devices; lead letters or lead tape are best.

Lead sheeting to protect parts of the patient not radiographed (also the film if only part used in one exposure).

THE PATIENT
Having established all the previously mentioned criteria; only then is it prudent to sedate or anaesthetise the patient for radiography. The following points are critical:

Sedation or anaesthesia are essential unless contra-indicated; manual holding is to be avoided if at all possible.

Ensure that endotracheal tubes, an anaesthetic machine and all the necessary anaesthetic equipment are on hand in the controlled area.

Emergency resuscitation equipment should also be available.

An assistant should be present to monitor the sedated or anaesthetised patient during the radiographic procedure

CHECK-LIST FOR THE PRACTICAL EXAMINATION

Start from the bottom upwards….

Lead sheeting; put in place even if the table is lead lined - double thickness is better.

Cassette.

Marker - Left or right marker plus date and patient identification; this should be in lead or perspex letters or inscribed on lead impregnated tape.

Grid; ensure that this is the correct way up (a grid ratio of 8:1 is suitable). The Potter Bucky moving grid incorporated into the table top is by far the best, but failing this a focused or pseudo-focused grid is acceptable (parallel grids may cause "grid cut-off"). The grid should be situated between the cassette and the patient.

Positioning aids - choose those relevant to the view required.

Finally, having established all other factors, position the patient (refer to Practical Task: Positioning).

Ensure that you are able to state the point of collimation of the primary beam.

Be aware of any potential hazards associated with radiography and be able to state these to the examiner (read this chapter fully and refer to regulations stated in Q1).

Radiography Equipment - Answers

Arlo Guthrie — Tue, 21 Apr 2009 06:13:07 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:13:07

ANSWERS

What is the output of most portable x-ray machines?
20-60 mA.

What is the maximum output of most mobile x-ray machines?
300 mA.

What is the maximum output of most fixed x-ray machines?
1250 mA.

What is the purpose of the line voltage compensator?
To control fluctuations in normal mains electricity which may cause inconsistent radiographic output.

Larger x-ray machines may possess a device which automatically controls electrical fluctuations; what is this device called?
An autotransformer.

What is the minimum distance away from the tube head that the exposure button may be situated?
At least 2 metres or can be moved to that distance via a cable.

What is the function of the kilovoltage (kV) control?
Selection of the penetrating power of the x-ray beam produced. This works by determination of the speed and kinetic energy with which the electrons hit the target. Remember that kV affects both the contrast and blackening of a radiograph.

What is another term for the kilovoltage applied across the tube?
Potential difference.

When would it be sensible to select a high kV setting?

For radiography of tissues with a high atomic number.

For radiography of tissues with a high specific gravity.

For radiography of very thick or deep tissues.

What is the function of the milliamperage (mA) control?
Determination of the quantity of x-rays produced (a measure of the number of electrons crossing the tube from cathode to anode during an exposure). Remember that mA affects only the blackening of the radiograph. This works by alteration of the amounts that the filament is heated.

What is the milliamperage also known as?
The tube current.

What unit denotes the product of the tube current (mA) and the length of exposure?
Milliampere seconds (mAs).
Exposure time (in seconds) = mAs divided by mA

In small x-ray machines, the kV may be directly linked to the mA. Why might this be disadvantageous?
Longer exposure times are necessary if both a high kV and mAs are required.

If the tube current (mA) is increased, how is the exposure time (mAs) affected?
A shorter exposure time (mAs) is necessary.
If mA is decreased, a longer exposure time will be required.

Why is it sensible to use the largest possible mA for a particular kV setting?
The longer the exposure time, the more likely you are to encounter movement blur.

If the kV were increased by 10, by how much would you need to reduce the mAs in order to produce a film of similar diagnostic quality to the exposures used initially?
The mAs should be halved.

What is meant by the film focal distance (FFD)?
The distance between the focal spot and the radiographic film. The greater the FFD, the lower the intensity of the x-ray beam.
A longer FFD therefore requires a higher mAs in order to prevent underexposure.

State the inverse square law.
The intensity of the x-ray beam varies inversely as the square of the distance from the source.
New mAs = Old mAs x New distance squared divided by old distance squared.

What is a suitable FFD for most portable x-ray machines?
75cm.

In addition to FFD, what other parameters must be kept constant when calculating exposures?

Line voltage.

Film-screen combination.

What device is used for measuring the depth of tissues?
Callipers.

What is the purpose of a grid?
To absorb scattered radiation.

How does a grid work?
The grid is a flat plate sited between the patient and cassette. It consists of narrow strips of lead alternating with strips of a radiolucent material such as plastic or aluminium. Undeflected photons passing through the patient pass through the interspaces, whilst oblique scattered radiation is absorbed largely by the lead strips.

List the 4 main types of stationary grid.

Parallel.

Focussed.

Pseudo-focused.

Crossed.

What is the name of the expensive, but very efficient moving grid which is built into the radiography table-top?
The Potter Bucky diaphragm.

Why is a focussed grid preferable to a parallel grid?
A parallel grid may cause "grid cut off" around the edges of the film, since x-ray photons at the perimeter of the primary beam may be absorbed by the lead strips. A focussed grid possesses gradually sloping strips on either side to allow for the divergence of the primary beam, therefore helping to avoid grid cut off.

What important factors must be taken into account when a grid is used?

Ensure that the grid is the right way up.

The mAs must be increased in order to compensate for the fact that some of the primary beam will be absorbed in addition to scattered radiation.

What is meant by the "grid factor"?
The amount by which the mAs is increased to compensate for losses from the primary beam absorbed by the grid. The grid factor is usually 2.5-3, but each grid has its own particular specification.

Define grid ratio.
The ratio of the height of the strips to the width of the radiolucent interspace. The larger the grid ratio, the more efficient it will be. Usual grid ratios are 5:1 - 10:1.

What is the main disadvantage of grid use (apart from cut off) and how might this be rectified?
Coarse grid lines on a film can cause image disruption. The use of a grid with a greater number of lines per cm and subsequently finer grid lines will cause less distraction when assessing an exposed image.

What is the purpose of intensifying screens?
As the name implies, these are responsible for intensifying the effect of x-rays on the radiographic film. Some x-ray photons emerging from the patient are converted into visible light photons by crystals of phosphorescent material contained within the screens. This enables the reduction of exposure times.

Where are the intensifying screens located?
Inside the x-ray cassette. The front screen is sited between the front radiolucent material and the x-ray film, whilst the rear screen is sited between the film and a felt pressure pad.

What colour light is emitted by calcium tungstate screens?
Blue light.

What colour light is emitted by rare earth phosphor screens?
Blue or green light.

Why are rare earth screens preferable to those of calcium tungstate?
Rare earth screens are more sensitive to the primary beam, which means that exposure factors may be significantly reduced.

Describe how you would clean an intensifying screen.
With care. Avoid scratches, abrasions, greasy fingerprints and chemical splashes. Always use a proprietary cleaner according to the manufacturer's instructions. Finish off with lens tissue to remove any traces of dust.

What film type is suitable for use with calcium tungstate screens or blue light emitting rare earth phosphors?
Monochromatic film.

What film type is suitable for use with green or blue light emitting rare earth phosphors?
Orthochromatic film.

When would non-screen film be utilised?
For intra-oral radiography where very fine detail is required.

What is the main disadvantage of non-screen film?
Longer exposure times are required in order to obtain a diagnostic image.

What is the main advantage of a fast film-screen combination?
Lower exposure factors are required than a slow system.
A fast film-screen combination is suitable for thoracic and abdominal radiographs.

What is the main disadvantage of a fast film-screen combination?
Blurring of the image.

What is the main advantage of a slow film-screen combination?
Higher definition images are produced than with a fast system.
A slow film-screen combination is suitable for skull and limb radiographs.

What is the main disadvantage of a slow film-screen combination?
Higher exposure factors are necessary than with a fast combination.

List 6 important factors regarding the storage of unexposed radiographic film.

Radiographic film must not be exposed to light.

Store well away from the controlled area (ideally in a lead-lined cupboard).

Keep in a clean, cool, dry place.

Store in an upright position, and within the manufacturer's packaging.

Never use film that has passed its expiry date.

Film may be refrigerated if it is exceptionally hot weather.

Radiography Equipment

Arlo Guthrie — Tue, 21 Apr 2009 06:12:14 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:12:14

QUESTIONS

What is the output of most portable x-ray machines?

What is the maximum output of most mobile x-ray machines?

What is the maximum output of most fixed x-ray machines?

What is the purpose of the line voltage compensator?

Larger x-ray machines may possess a device which automatically controls electrical fluctuations; what is this device called?

What is the minimum distance away from the tube head that the exposure button may be situated?

What is the function of the kilovoltage (kV) control?

What is another term for the kilovoltage applied across the tube?

When would it be sensible to select a high kV setting?

What is the function of the milliamperage (mA) control?

What is the milliamperage also known as?

What unit denotes the product of the tube current (mA) and the length of exposure?

In small x-ray machines, the kV may be directly linked to the mA. Why might this be disadvantageous?

If the tube current (mA) is increased, how is the exposure time (mAs) affected?

Why is it sensible to use the largest possible mA for a particular kV setting?

If the kV were increased by 10, by how much would you need to reduce the mAs in order to produce a film of similar diagnostic quality to the exposures used initially?

What is meant by the film focal distance (FFD)?

State the inverse square law.

What is a suitable FFD for most portable x-ray machines?

In addition to FFD, what other parameters must be kept constant when calculating exposures?

What device is used for measuring the depth of tissues?

What is the purpose of a grid?

How does a grid work?

List the 4 main types of stationary grid.

What is the name of the expensive, but very efficient moving grid which is built into the radiography table-top?

Why is a focussed grid preferable to a parallel grid?

What important factors must be taken into account when a grid is used?

What is meant by the "grid factor"?

Define grid ratio.

What is the main disadvantage of grid use (apart from cut off) and how might this be rectified?

What is the purpose of intensifying screens?

Where are the intensifying screens located?

What colour light is emitted by calcium tungstate screens?

What colour light is emitted by rare earth phosphor screens?

Why are rare earth screens preferable to those of calcium tungstate?

Describe how you would clean an intensifying screen.

What film type is suitable for use with calcium tungstate screens or blue light emitting rare earth phosphors?

What film type is suitable for use with green or blue light emitting rare earth phosphors?

When would non-screen film be utilised?

What is the main disadvantage of non-screen film?

What is the main advantage of a fast film-screen combination?

What is the main disadvantage of a fast film-screen combination?

What is the main advantage of a slow film-screen combination?

What is the main disadvantage of a slow film-screen combination?

List 6 important factors regarding the storage of unexposed radiographic film.

Introduction & Syllabus

Arlo Guthrie — Tue, 21 Apr 2009 06:09:22 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 07:09:22

Introduction & Syllabus

Under Construction
The Revision Guide For Student Nurses was first published in 2000 to provide a modern approach to revision with full coverage of the RCVS Veterinary Nursing syllabus. It will shortly be updated to reflect recent changes in the syllabus.

It is dedicated to Stella.

Vanessa Bird
April 2009

Introduction & Syllabus

Arlo Guthrie — Thu, 09 Apr 2009 16:03:03 GMT
Revision 2 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 09/04/2009 17:03:03

General Introduction & Syllabus

Under Construction

General Introduction

Arlo Guthrie — Fri, 23 Jan 2009 12:58:24 GMT
Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 23/01/2009 12:58:24

Under Construction

Producing A Radiographic Image

Arlo Guthrie — Tue, 21 Apr 2009 05:59:27 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:59:27

QUESTIONS

Define radiography.

Define radiology.

Which 2 members of the electromagnetic spectrum possess the highest frequency and the shortest wavelength?

What are electromagnetic radiations made up of?

What 4 properties are possessed by all the members of the electromagnetic spectrum?

What 3 special properties do x-rays possess?

What is an atom?

What is meant by the "atomic number" of an element?

What is a compound?

X-rays are generated in the tube head of the x-ray machine. Name the 2 types of tube head available.

Why is a rotating anode superior to a stationary anode?

A rotating anode is mounted upon a molybdenum rod which spins at speeds of up to 10,000 rpm. Why is molybdenum used?

At what angle is the target area set on a rotating anode?

What is the cathode?

Why is tungsten the material of choice for the cathode?

What is the anode?

How are x-ray photons produced within the tube head?

What 2 factors increase the speed of the electrons travelling from the filament to the target?

What is the glass envelope contained within and why?

What is the term used to describe a small electrical current passed through a filament and the subsequent release of an electron cloud following heat generation?

What is the function of the step-down or filament transformer?

What is the function of the step-up or high-tension transformer?

What is the function of the focusing cup?

What is the focusing cup made of?

Why is the target set in a copper stem?

What is meant by the terms "actual focal spot" and "effective focal spot"?

How is focal spot size adjusted?

What is the advantage of the fine focus?

What is the advantage of the coarse (or broad) focus?

What is the main disadvantage of the fine focus?

What is the main disadvantage of the coarse (or broad) focus?

Define the "penumbra effect".

Radiography

Arlo Guthrie — Tue, 21 Apr 2009 05:58:25 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:58:25

Radiography

Radiography = The production of diagnostic films by exposure to x-rays.

Radiology = The science of radiation.

Radiography is an extremely useful aid in the diagnosis of many diseases and conditions commonly seen in small animal practice. It is a procedure in which veterinary nurses are required to perform an active role, from positioning the patient to developing the exposed films. Radiation is a significant risk, and emphasis is placed upon the health and safety aspects of this subject.

As with all procedures, a veterinary nurse should receive adequate training prior to undertaking any radiographic task. The practice must clearly display the local rules and written systems of work relevant to the controlled area and the dark room. In addition, a copy of the Guidance Notes for the Protection of Persons against Ionising Radiations arising from Veterinary Use should be available for all personnel to read.

Learning Objectives
The learning objectives of this chapter are:

To understand how a radiographic image is produced.

To gain a thorough working knowledge of the equipment used in radiography.

To be able to correctly position a patient for radiography and to select the correct settings, collimation and centring points for various parts of the anatomy.

To understand the techniques of both manual and automatic developing and identify film faults.

To gain a good understanding of the principles of contrast radiography.

To fully understand the health and safety issues affecting personnel involved in veterinary radiography

Radiography

Arlo Guthrie — Tue, 21 Apr 2009 05:57:36 GMT
Revision 1 posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:57:36

Radiography = The production of diagnostic films by exposure to x-rays.

Radiology = The science of radiation.

Radiography is an extremely useful aid in the diagnosis of many diseases and conditions commonly seen in small animal practice. It is a procedure in which veterinary nurses are required to perform an active role, from positioning the patient to developing the exposed films. Radiation is a significant risk, and emphasis is placed upon the health and safety aspects of this subject.

As with all procedures, a veterinary nurse should receive adequate training prior to undertaking any radiographic task. The practice must clearly display the local rules and written systems of work relevant to the controlled area and the dark room. In addition, a copy of the Guidance Notes for the Protection of Persons against Ionising Radiations arising from Veterinary Use should be available for all personnel to read.

Medical Nursing - Glossary

Arlo Guthrie — Tue, 21 Apr 2009 05:51:57 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:51:57

Acanthosis nigricans = A cutaneous reaction characterised by skin thickening, alopecia and excessive pigmentation. The cause may be due to friction, allergy or a hormone imbalance.

Addison's disease = See hypoadrenocorticism.

Alopecia = The loss of hair from any site and for any reason.

Anaemia = Deficiency of quality or quantity of red corpuscles in the blood.

Antitussive = An agent that suppresses coughing.

Anuria = Cessation of the secretion of urine.

Aortic stenosis = Narrowing of the aorta.

Apnoea = Cessation of breathing.

Arthritis = Inflammation of one or more joints.

Ascites = Free fluid in the peritoneal cavity.

Atopy = A state of hypersensitivity to certain antigens.

Aura = The premonition that often precedes an epileptic fit.

Aural haematoma = A blood filled swelling of the pinna (usually secondary to trauma/head shaking as a result of an ear infection).

Auroscope = An instrument used to examine the inside of the ears; also known as an otoscope.

Azotaemia = Excessive nitrogen containing compounds in the blood.

Blepharitis = Inflammation of the eyelids.

Blepharospasm = Spasm of the obicularis muscle of the eyelid, often the result of a foreign body or corneal injury.

Bradypnoea = Lowered respiratory rate.

Bulla osteotomy = Removal of the tympanic bulla in order to drain the middle ear in cases of otitis media.

Bursitis = Inflammation of the bursa.

Cachexia = Accelerated starvation; extreme debility and emancipation; typical of the late stage of serious disease.

Cardiomyopathy = A chronic disorder of the heart muscle.

Cellulitis = A diffuse inflammation of connective tissue, especially of subcutaneous tissue.

Chorioretinitis = An inflammatory condition of both the choroid and the retina of the eye.

Chylothorax = The presence of effused chyle in the pleural cavity.

Clonic = The second stage of a grand mal fit.

Colitis = Inflammation of the colon.

Conjunctivitis = Inflammation of the conjunctiva.

Corneal oedema = Excessive accumulation of fluid within the cornea.

Corneal pannus = Chronic progressive keratitis and vascularisation of the cornea.

Corneal sequestrum = An avascular response to corneal injury.

Cushing's disease = See hyperadrenocorticism.

Cyanosis = A bluish appearance of the mucous membranes caused by imperfect oxygenation of the blood; indicative of circulatory failure and is common in respiratory diseases.

Cystitis = Inflammation of the urinary bladder.

Dermatitis = Inflammation of the skin.

Diabetes insipidus = A disease that arises as a result of posterior pituitary dysfunction; characterised by an increased flow of urine of a low specific gravity and polydipsia.

Diabetes mellitus = A disturbance in the oxygenation and utilisation of glucose, which is secondary to the malfunction of the beta cells of the pancreas, whose function is the production and release of insulin.

Distichiasis = A row of eyelashes turned against the eyelid that cause irritation.

Diuresis = Increased excretion of urine.

DJD = Degenerative joint disease; a progressive condition that leads to the erosion of cartilage and the formation of new bone deposits around the joints.

Dry eye = See Keratoconjunctivitis sicca (KCS).

Dyspnoea = Difficulty breathing.

Dysuria = Difficult or painful micturition (urination).

Ectopic = Located away from the normal anatomic position.

Ectropion = An outwardly turning eyelid margin.

Endocardiosis = Progressive degeneration of the cardiac atrioventricular valves.

Endocarditis = Inflammation of the lining membrane and muscles of the heart.

Enophthalmos = A condition in which the eyeball is abnormally sunken into its socket.

Entropion = An inwardly turning eyelid margin.

EPI = Exocrine pancreatic insufficiency; dysfunction of the exocrine pancreas as a result of atrophy of the acinar cells or from chronic pancreatitis.

Erythema = Redness of the skin caused by congestion of the capillaries in its lower layers.

Excoriation = An abrasion of the skin; often as a result of self-inflicted trauma following conditions such as flea allergy dermatitis.

Expectorant = A remedy which facilitates the coughing up of sputum.

Epiphora = Excessive lacrimation.

Epistaxis = Nose bleed.

Gastritis = Inflammation of the lining of the stomach.

Glaucoma = Raised intraocular pressure.

Glomerulonephritis = Inflammation of the glomeruli of the kidneys.

Grand mal = A major epileptic seizure.

Folliculitis = Inflammation of the hair follicles.

GDV = Gastric dilation volvulus; distension of the stomach with gas, which is unable to escape due to twisting.

Haemothorax = The presence of blood in the thoracic cavity.

Hemiplegia = Paralysis of one half of the body; the lesion is on the side of the brain opposite to the one paralysed.

Hepatic lipidosis = A serious condition of cats also known as fatty liver.

Hepatitis = Inflammation of the liver; usually due to viral infection or toxicity.

Hip dysplasia = A hereditary condition typically affecting large breeds of dog, especially the German Shepherd; the head of the femur does not fit correctly into the acetabulum.

Horner's syndrome = A condition in which there is a lesion on the path of sympathetic nerve fibres in the cervical region; symptoms include enophthalmos, ptosis and a contracted pupil.

Hydrocephalus = Enlargement of the skull caused by an accumulation of fluid around the brain or in the ventricles.

Hydrothorax = The presence of effused fluid in the pleural cavity.

Hyperadrenocorticism = A condition of over-secretion by the adrenal cortex. This may be due to a tumour of the adrenal cortex or pituitary gland. Also known as Cushing's disease or PDH (pituitary dependent hyperadrenocorticism).

Hyperaesthesia = Excessive sensitivity to touch and other sensations.

Hyperglycaemia = Excessive glucose in the blood.

Hyperkinesis = Excessive motor activity.

Hyperpnoea = Increased respiratory rate and depth.

Hyperthyroidism = Excessive activity of the thyroid gland. This condition is more common in cats than in dogs and is characterised by weight loss and tachycardia.

Hyphaema = Haemorrhage into the anterior chamber of the eye.

Hypoadrenocorticism = The underproduction of the hormones of the adrenal cortex; also known as Addison's disease.

Hypoglycaemia = An insufficiency of blood glucose.

Hypothyroidism = An insufficiency of thyroid secretion.

Icterus = Jaundice.

Idiopathic = Of unknown cause or origin.

IMHA = Immune mediated haemolytic anaemia.

Impetigo = A superficial, bacterial skin infection that is most often seen in puppies. It is characterised by multiple pustules and yellow scabs, particularly on the ventral abdomen; also known as juvenile pustular dermatitis or puppy pyoderma.

Interdigital dermatitis = See pododermatitis.

Iridocyclitis = Inflammation of the iris and ciliary body.

Labial dermatitis = Inflammation of the skin of the lips; usually seen in "jowly" dogs.

Juvenile pustular dermatitis = See impetigo.

Keratitis = Inflammation of the cornea.

Keratoconjunctivitis sicca = Inflammation of the cornea and conjunctiva due to insufficient tear production; also known as dry eye.

Ketoacidosis = A serious condition of diabetic animals that arises from the build up of ketones that accumulate in the blood.

Lacrimation = Tear production.

Marie's disease = Also known as chronic pulmonary arthroplasty. This disease of dogs is seen as a thickening of certain bones as a result of an intrathoracic or intrabdominal mass.

Meningitis = Inflammation of the meninges of the brain. The cause may be viral, bacterial, fungal or toxic.

Miotic drug = A drug that causes constriction of the pupil.

Moist dermatitis = See wet eczema.

Mucolytic = A drug that softens mucus, thus reducing the viscosity of bronchial secretions.

Myasthenia gravis = An extreme form of progressive muscle weakness.

Mydriatic drug = A drug that causes the pupil to dilate.

Nephritis = Inflammation of the kidney.

OCD = Osteochondritis dessicans; a disease of young dogs in which cartilage becomes excessively thickened.

Oliguria = A deficient secretion of urine.

Ophthalmoscope = An instrument used to illuminate and examine the interior of the eye.

Orthopnoea = Difficulty breathing whilst in recumbency.

Osteochondrosis = A developmental disease of articular cartilage in which the long bones are principally affected.

Osteodystrophy = Disease of bone during its development and growth.

Osteomalacia = A disease of bone that arises as a result of insufficient vitamin D; also known as Rickets.

Osteopathy = Any disease of bone.

Osteopenia = Abnormal rarefaction of bone that leads to the thinning of the skeleton and excessive bone resorption.

Osteoporosis = See osteopenia.

Otitis externa = Inflammation of the external ear canal.

Otitis interna = Inflammation of the inner ear.

Otitis media = Inflammation of the middle ear cavity.

Otodectes cyanotis = Ear mites.

Otoscope = See auroscope.

Ottorhoea = Any discharge from the ear.

Pancreatitis = Inflammation of the pancreas.

Panosteitis = Inflammation of all the structures of a bone.

Paracentesis = The puncture of the wall of a cavity with a needle, in order to draw off excess fluid or to obtain a sample for analysis.

Paralysis = Complete loss of function of an area of the body.

Paraparesis = Partial paralysis.

Paraplegia = Paralysis of the hind limbs.

Paresis = Muscle weakness with neurological deficits; the animal is still able to make coordinated walking movements providing that the body is supported.

Patent ductus arteriosus (PDA) = Failure of the ductus arteriosus to close as it should within a few days following birth.

Petit mal = A mild epileptic seizure.

Pinna = The earflap.

Pleurisy = Inflammation of the pleura.

Pneumonia = Inflammation of the lung with consolidation and exudation.

Pneumothorax = The presence of air within the pleural cavity.

Pododermatitis = Inflammation of the skin between the digits; also known as interdigital dermatitis.

Polyarthritis = The inflammation of several joints at the same time.

Polyuria = Increased frequency of urination.

Portosystemic shunt = Any vascular anastomosis between the hepatic portal vein and the systemic circulation.

Pruritis = Extreme irritation of the skin; a sensation within the skin that produces the desire to scratch in order to relieve the irritation.

Psychogenic neurodermatitis = A skin disease of cats associated with continual licking, cleaning or hair-pulling, attributed to stress factors or anxiety neurosis.

Psychogenic polydipsia = Excessive drinking due to stress related reasons rather than a physical cause.

Ptosis = Dropping of the upper eyelid due to paralysis of the 3rd cranial nerve.

Ptyalism = An abnormally large secretion of saliva.

Pulmonic stenosis = A congenital condition in which the cusps of the pulmonic heart valve are malformed. This may cause right-sided heart failure.

Pyelonephritis = Inflammation of the renal pelvis and cortex.

Pyoderma = Any purulent skin disease.

Pyothorax = Pus within the thoracic cavity.

Quadriplegia = Paralysis in which all 4 of the limbs are affected.

Rhinitis = Inflammation of the nasal mucous membranes.

Seborrhoea = an abnormally copious excretion of sebum that may make the skin appear oily.

Sertoli cell tumour = A neoplastic growth within the testis that may produce oestrogens that cause feminisation. Cryptorchid animals are most at risk.

Status epilepticus = A severe form of seizure in which the animal suffers a rapid succession of fits.

Syncope = A faint.

Tachypnoea = Increased respiratory rate.

Tenesmus = Painful or ineffectual attempts to urinate or defecate.

Tetraplegia = See quadriplegia.

Tonic phase = The period during a seizure in which the muscles tense up.

Tympanic membrane = The eardrum.

Urticaria = An acute or chronic allergic skin condition characterised by the recurrent appearance of an eruption of weals causing great irritation.

Uveitis = Inflammation of the uveal tract.

Von Willebrand's disease = An inherited bleeding disorder that arises as a result of clotting factor VIII. Dobermans are particularly susceptible.

Wet eczema = A nasty skin infection that comes up very quickly and is extremely red, sore and itchy; usually occurs as a result of an allergic reaction. Also known as acute moist dermatitis.

Wobbler syndrome = A neurological condition in which progressive ataxia and neck pain arise due to pressure on the cervical spinal cord from unstable discs, deformed vertebrae or hypertrophied spinal ligaments. This condition is also known as cervical spondylopathy.

Medical Nursing - Summary And Further Reading

Arlo Guthrie — Tue, 21 Apr 2009 05:50:47 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:50:47

An understanding of the medical conditions and diseases affecting small animals will help you to provide excellent nursing care. Sometimes it can be daunting trying to remember all the names of drugs used for certain conditions, especially when products are constantly being updated. Try keeping a notebook with subheadings for each category. This will also help you to remember the names of the medical diseases and conditions that they are used to treat.

Example: Subcategory A / Drugs used in the Treatment of Ophthalmic Conditions

Drug name

Main active ingredient

Type of drug

Examples of use

Notes

Aureomycin

Tetracycline

Topical eye ointment

Conjunctivitis

Vet A uses this often, but Vet B prefers Fucithalmic.

If you are nursing a patient with diarrhoea, it is one thing knowing how to deal with the basic management of such a case, but it is far better to know:

Is the cause infectious?

If cause unknown what tests might be suitable to find out?

What medication might the animal respond to?

Is the animal on any concurrent medication that might be making matters worse?

What dietary requirements are needed?

Yes, the veterinary surgeon in charge of the patient will make the decisions, but being able to ask intelligent questions will assist with the smooth handling of the case - especially bearing in mind that some veterinary surgeons are so busy, that they often leave far more to their nurses than perhaps they should! I am certainly not suggesting that nurses should know as much as the vets - but an inside knowledge is not only beneficial to your studies, but makes real-life cases very much more interesting.

Suggested reading:

Veterinary Nursing (Butterworth Heinemann) - Edited by D R Lane & B Cooper - Chapter 17 Medical Disorders & their Nursing - by J Simpson.

Small Animal Nutrition (Butterworth Heinemann) - by Sandie Agar.

Paresis & Paralysis - Answers

Arlo Guthrie — Tue, 21 Apr 2009 05:49:08 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:49:08

ANSWERS

Define paresis.
Limb weakness that arises as a result of injury to the brain or spinal cord.

Define paralysis.
Complete loss of function of an area of the body.

What is the term that describes hind limb paralysis?
Paraplegia.

What is paraparesis?
Incomplete paralysis affecting the hind limbs.

What is the term that describes the paralysis of all 4 limbs?
Tetraplegia (or quadriplegia).

What is the term that describes paralysis involving a forelimb and a hind limb on the same side of the body?
Hemiplegia.

List nursing considerations that must be taken into account when nursing a paralysed animal.

Ensure plenty of soft deep bedding to avoid decubitus ulcers.

Be aware that assistance will be necessary with urination, defecation and grooming.

Plenty of reassurance and TLC will be necessary.

Physiotherapy may prove beneficial.

Be patient and advise owners that recovery may be very time consuming.

Use a sling to assist larger dogs; never try to lift a dog alone that is too heavy.

Paresis & Paralysis

Arlo Guthrie — Tue, 21 Apr 2009 05:48:16 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:48:16

QUESTIONS

Define paresis.

Define paralysis.

What is the term that describes hind limb paralysis?

What is paraparesis?

What is the term that describes the paralysis of all 4 limbs?

What is the term that describes paralysis involving a forelimb and a hind limb on the same side of the body?

List nursing considerations that must be taken into account when nursing a paralysed animal.

Seizures - Answers

Arlo Guthrie — Tue, 21 Apr 2009 05:45:59 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:45:59

ANSWERS

By what other names might a seizure be known?

Convulsion.

Ictus.

Fit.

Describe the clinical signs that may occur during a seizure.

Generalised, spasmodic, involuntary contractions of the body and limbs, alternating with relaxation.

Loss of consciousness.

Aggression.

Salivation/drooling.

Collapse.

Glazed expression.

Lack of response to stimuli.

What is the name given to a series of rapid epileptic spasms that occur without periods of consciousness that may last for many hours.
Status epilepticus.

What is the name of the drug that may be used to sedate animals suffering from status epilepticus?
Sagatal.

What is meant by idiopathic epilepsy?
Epilepsy of unknown cause.

What breed of dog is most commonly affected by seizures occurring as a result of a brain tumour?
Boxer.

What is syncope?
A fainting episode.

Seizures may arise as a result of inflammation to the brain. Can you state 2 examples of bacterial infections that may cause such seizures?

Bacterial meningitis.

Abscess.

Give 3 examples of viral infections that may cause inflammation to the brain resulting in seizures.

Viral meningitis.

Canine distemper.

Rabies.

Feline panleucopenia.

FIP.

FeLV.

What is the name of the condition characterised by an accumulation of CSF in the cranium that may cause seizures?
Hydrocephalus.

Give 2 examples of dog breeds predisposed to hydrocephalus.

Chihuahua.

Pomeranian.

List 5 toxins that may cause seizures.

Ethylene glycol.

Arsenic.

Metaldehyde.

Alphachoralose.

Strychnine.

What is the name of the condition in which blood calcium is too low that may cause seizures?
Hypocalcaemia.

What is the name of the condition in which blood glucose is too low that may cause seizures?
Hypoglycaemia.

What is the name of the period prior to a fit?
The aura.

List 6 signs that may occur during the aura.

Restlessness.

Staring expression.

Salivation.

Licking of the lips.

Muscle twitching.

Hyperaesthesia.

What may occur during the clonic phase of a fit?

Purposeless running movements of the limbs.

Voiding of urine and faeces.

During which phase of a fit would hyperextension of the limbs and body occur?
The tonic phase.

How long is the post ictal phase of a fit?
This is of variable duration and may last from 30 seconds up to an hour.

A client telephones the surgery in a panic. Her boxer is fitting and she wants to bring him to the surgery immediately. Why would you advise against this, and what advice would you recommend?

Unless the animal is in status epilepticus the best first aid is to allow the fit to pass naturally.

Advise that trying to handle the dog during the fit may result in the owner being bitten.

Advise that the owner move any objects that may prove injurious away from the dog.

Suggest that she draw the curtains and switch off the television/radio. A calm, quiet environment must be provided.

Advise that although a fit is very frightening for an owner to witness, it will pass, and it is better for all concerned if she tries to remain calm.

Recommend that a note is taken of the date, time and duration of the fit.

Allow adequate time to recover before bringing the dog to the surgery.

Stimulation during a journey may provoke further fits.

If this is a first fit, and the dog is not known to be epileptic, advise that the owner check the house and garden for potential toxins.

List 4 drugs that may be used to help to control epilepsy.

Epiphen (phenobarbitone).

Mysoline.

Diazepam (valium).

Genetrix (potassium bromide).

What is the name given to a short-duration fit that may only manifest itself as muscle tremors?
Petit mal fit.

Seizures

Arlo Guthrie — Tue, 21 Apr 2009 05:44:45 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:44:45

QUESTIONS

By what other names might a seizure be known?

Describe the clinical signs that may occur during a seizure.

What is the name given to a series of rapid epileptic spasms that occur without periods of consciousness that may last for many hours.

What is the name of the drug that may be used to sedate animals suffering from status epilepticus?

What is meant by idiopathic epilepsy?

What breed of dog is most commonly affected by seizures occurring as a result of a brain tumour?

What is syncope?

Seizures may arise as a result of inflammation to the brain. Can you state 2 examples of bacterial infections that may cause such seizures?

Give 3 examples of viral infections that may cause inflammation to the brain resulting in seizures.

What is the name of the condition characterised by an accumulation of CSF in the cranium that may cause seizures?

Give 2 examples of dog breeds predisposed to hydrocephalus.

List 5 toxins that may cause seizures.

What is the name of the condition in which blood calcium is too low that may cause seizures?

What is the name of the condition in which blood glucose is too low that may cause seizures?

What is the name of the period prior to a fit?

List 6 signs that may occur during the aura.

What may occur during the clonic phase of a fit?

During which phase of a fit would hyperextension of the limbs and body occur?

How long is the post ictal phase of a fit?

A client telephones the surgery in a panic. Her boxer is fitting and she wants to bring him to the surgery immediately. Why would you advise against this, and what advice would you recommend?

List 4 drugs that may be used to help to control epilepsy.

What is the name given to a short-duration fit that may only manifest itself as muscle tremors?

Diseases Of The Ear & Eye - Answers

Arlo Guthrie — Tue, 21 Apr 2009 05:43:31 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:43:31

ANSWERS

Note that some of the questions in this section (those marked with an asterisk) are more advanced than required for the final V.N. exams. However, they are of interest to those already qualified, or studying for the Medical Diploma.

What is the instrument used to look inside a patient's ear known as?
An otoscope or auroscope.

What is the correct name for the earflap?
The pinna.

What is the correct name for the eardrum?
The tympanic membrane.

What is the correct name for the ear canal?
The external auditory meatus.

What is the correct term for inflammation of the ear?
Otitis.

Briefly describe the 3 types of otitis.

Otitis externa - inflammation of the external auditory meatus.

Otitis media - inflammation of the middle ear cavity.

Otitis interna - Inflammation of the inner ear (this affects the organs of balance, and less commonly, hearing).

State 3 surgical operations that may be performed in cases of severe, chronic otitis.

Total ear canal ablation (TECA) - resection of both the vertical and horizontal parts of the ear canal

Vertical canal ablation (VCA) - resection of the vertical part of the ear canal.

Lateral wall resection - resection of the horizontal part of the ear canal.

What is a bulla osteotomy?
Removal of the tympanic bulla in order to drain the middle ear in cases of otitis media.

What is otorrhoea?
Any discharge from the ear.

Describe how to clean a patient's ears.

Talk to, and calm the patient.

Ensure that the animal is adequately restrained. If the ears are very sore - sedation or general anaesthesia may be necessary.

Adorn protective apron and gloves.

Examine the ear and report any abnormal findings to the veterinary surgeon (eg. excessive hair growth within the canal, foreign material, excessive wax, earmites). If a swab is required for culture and sensitivity, this must be taken prior to cleaning.

Select a suitable preparation, and remember to check the expiry date before use. Invert the product a few times prior to use.

Squeeze a liberal amount carefully down into the ear canal.

Gently massage the base of the ear to ensure that the preparation is adequately dispersed. This action also helps to break down any hard wax.

Use a pad of cotton wool to clean the ear canal. Always be extremely careful in order to avoid damage to the tympanic membrane. For the same reason, cotton buds should not be used within the ear canal, although they can be used in the small crevices of auricular cartilage.

Discard soiled cotton wool in the clinical waste bin.

Repeat until no further wax is evident, although be aware that excessive friction may make the ear very sore.

Excessive hairs within the ear canal may require plucking with forceps.

Clean the nozzle of the ear cleaner before commencing with the second ear (this prevents cross infection from one ear to the other).

A Springer spaniel is dispensed an ear cleaning solution and a topical antibiotic preparation. What advice would you give to the client about their use?

Keep the drugs in a safe place away from direct heat or sunlight.

Advise on the frequency of use.

Advise that the ear cleaner should be used prior to topical antibiotic preparation.

Demonstrate the correct method of ear cleaning (as per your answer to Q9).

Advise the quantity of drug to be given.

Recommend that should the ear condition worsen then the client must stop the therapy and contact the surgery at once.

What is the correct term for ear mites?
Otodectes cyanotis.

A Boxer dog is brought to the surgery following repeated bouts of head shaking. What tests might be performed, and why?

Examination of the ears with an otoscope/auroscope - assess for the presence of excessive wax, pus, foreign material, excessive hair, ear mites etc.

Ear swab/s - for culture and sensitivity.

What condition of the ear may arise following repeated head shaking?
Aural haematoma.

List 3 preparations commonly used in small animal medicine for ear cleaning.

Leo Dog/Cat Ear Cleaner.

Dermisol Multicleanse Solution.

Allerderm Epiotic.

List 5 topical antibiotic preparations used in the treatment of ear conditions.

Aurizon.

Canaural.

Panolog.

Surolan.

Genticin drops.

What is the name of the instrument that projects light onto the eye and into the fundus so that the structure can be examined?
An ophthalmoscope.

What is the correct name for tear production?
Lacrimation.

Define the following: conjunctivitis, keratitis, blepharitis, blepharospasm and uveitis.

Conjunctivitis - inflammation of the conjunctiva.

Keratitis - inflammation of the cornea.

Blepharitis - inflammation of the eyelids.

Blepharospasm - spasm of the obicularis muscle of the eyelid.

Uveitis - inflammation of the uveal tract.

Describe the symptoms of glaucoma.

Cloudy, oedematous, insensitive cornea.

Increase in intraocular pressure.

Enlarged globe.

Congested episcleral vessels.

Vision loss.

What is the name of the simple test that may be used to aid the diagnosis of corneal ulceration?
Fluorescein stain.

What is the name given to the group of drugs that dilate the pupil?
Mydriatics.

List 6 possible causes of conjunctivitis.

Ocular infection.

Ocular foreign body.

Entropion.

Ectropion.

Distichiasis.

Inflammatory diseases of the eyeball.

List 4 topical antibiotic drugs that may be used in the treatment of conjunctivitis.

Aureomycin eye ointment.

Chloramphenicol eye drops/ointment.

Fucithalmic.

Orbenin eye ointment.

State 2 preparations used as artificial tear drops in cases of keratoconjunctivitis sicca (dry eye).

Lacrilube.

Viscotears.

Which breed of dog is predisposed to keratoconjunctivitis sicca?
The West Highland White Terrier.

List 6 signs of keratoconjunctivitis sicca.

Tacky, mucoid ocular discharge.

Corneal dryness.

Ulceration.

Opacification.

Vascularisation and pigmentation.

Dryness of the nostrils.

* State the specific treatment for KCS in cases where the cause is autoimmune disease of the lacrymal gland.
Optimmune.

By what other name might chronic superficial keratitis be known?
Corneal pannus.

* Which breed of dog is primarily predisposed to corneal pannus?
The German Shepherd.

List 5 signs of keratitis.

Lacrimation.

Blepharospasm.

Corneal opacity.

Corneal vascularisation.

Pigmentation.

* By what other name might anterior uveitis be known?
Iridocyclitis.

What is the name of the test used to determine whether tear production is adequate?
Schirmer Tear Test.

Which infectious disease of dogs is associated with corneal oedema (blue-eye)?
Infectious canine hepatitis (the CAV-1 virus).

What is epiphora?
Persistent overflow of tears.

* What is the name of the disease most commonly seen in longhaired cats that is characterised by a "tea leaf" mass on the corneal surface, superficial vascularisation, blepharospasm and epiphora?
Corneal sequestrum (corneal mummification).

Define the following: miosis, ptosis and enophthalmos.

Miosis - contraction of the pupil of the eye.

Ptosis - dropping of the eyelid due to paralysis of the 3rd cranial nerve.

Enopthalmos - a condition in which the eyeball is abnormally sunken into its socket.

* State the condition characterised by the symptoms listed in Q31.
Horner's syndrome.

What is hyphaema?
Haemorrhage into the anterior chamber of the eye.

List 6 possible causes of hyphaema.

Trauma.

Penetrating foreign bodies.

Anterior uveitis.

Intraocular tumours.

Clotting and bleeding disorders.

Collie eye anomaly.

* List 5 possible causes of retinal detachment.

Chorioretinitis.

Hypertension.

Diabetes mellitus.

Neoplasia.

Trauma.

A diet deficient in what may cause central retinal atrophy, eventual blindness and/or dilated cardiomyopathy in cats?
Taurine.

Diseases Of The Ear & Eye

Arlo Guthrie — Tue, 21 Apr 2009 05:42:37 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:42:37

QUESTIONS

Note that some of the questions in this section (those marked with an asterisk) are more advanced than required for the final V.N. exams. However, they are of interest to those already qualified, or studying for the Medical Diploma.

What is the instrument used to look inside a patient's ear known as?

What is the correct name for the earflap?

What is the correct name for the eardrum?

What is the correct name for the ear canal?

What is the correct term for inflammation of the ear?

Briefly describe the 3 types of otitis.

State 3 surgical operations that may be performed in cases of severe, chronic otitis.

What is a bulla osteotomy?

What is otorrhoea?

Describe how to clean a patient's ears.

A Springer spaniel is dispensed an ear cleaning solution and a topical antibiotic preparation. What advice would you give to the client about their use?

What is the correct term for ear mites?

A Boxer dog is brought to the surgery following repeated bouts of head shaking. What tests might be performed, and why?

What condition of the ear may arise following repeated head shaking?

List 3 preparations commonly used in small animal medicine for ear cleaning.

List 5 topical antibiotic preparations used in the treatment of ear conditions.

What is the name of the instrument that projects light onto the eye and into the fundus so that the structure can be examined?

What is the correct name for tear production?

Define the following: conjunctivitis, keratitis, blepharitis, blepharospasm and uveitis.

Describe the symptoms of glaucoma.

What is the name of the simple test that may be used to aid the diagnosis of corneal ulceration?

What is the name given to the group of drugs that dilate the pupil?

List 6 possible causes of conjunctivitis.

List 4 topical antibiotic drugs that may be used in the treatment of conjunctivitis.

State 2 preparations used as artificial tear drops in cases of keratoconjunctivitis sicca (dry eye).

Which breed of dog is predisposed to keratoconjunctivitis sicca?

List 6 signs of keratoconjunctivitis sicca.

* State the specific treatment for KCS in cases where the cause is autoimmune disease of the lacrymal gland.

By what other name might chronic superficial keratitis be known?

* Which breed of dog is primarily predisposed to corneal pannus?

List 5 signs of keratitis.

* By what other name might anterior uveitis be known?

What is the name of the test used to determine whether tear production is adequate?

Which infectious disease of dogs is associated with corneal oedema (blue-eye)?

What is epiphora?

* What is the name of the disease most commonly seen in longhaired cats that is characterised by a "tea leaf" mass on the corneal surface, superficial vascularisation, blepharospasm and epiphora?

Define the following: miosis, ptosis and enophthalmos.

* State the condition characterised by the symptoms listed in Q31.

What is hyphaema?

List 6 possible causes of hyphaema.

* List 5 possible causes of retinal detachment.

A diet deficient in what may cause central retinal atrophy, eventual blindness and/or dilated cardiomyopathy in cats?

Diseases Of The Cutaneous System - Answers

Arlo Guthrie — Tue, 21 Apr 2009 05:41:16 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:41:16

ANSWERS

Note that some of the questions in this section (those marked with an asterisk) are more advanced than required for the final V.N. exams. However, they are of interest to those already qualified, or studying for the Medical Diploma.

Define the following: pruritis, seborrhoea and pyoderma.

Pruritis - a sensation within the skin that produces the desire to scratch in order to relieve the irritation.

Seborrhoea - an abnormally copious excretion of sebum that may make the skin appear oily.

Pyoderma - any pyogenic (pus producing) skin infection; usually secondary to some other skin disease.

What is the term that describes redness of the skin caused by congestion of the capillaries in its lower layers?
Erythema.

*What is the most common pathogen isolated in cases of canine pyoderma?
Staphylococcus intermedius.

*List 3 secondary opportunistic bacteria that are commonly associated with Staphylococcus intermedius in cases of canine pyoderma.

Proteus.

Pseudomonas.

Corynebacterium.

What is the general term used to describe the loss of hair from any site and for any reason?
Alopecia.

List 5 hormonal diseases that may cause bilaterally symmetrical alopecia.

Canine ovarian imbalances.

Feline hormonal alopecia.

Hyperadrenocorticalism.

Hypothyroidism.

Sertoli cell tumour.

By what other name might acute moist dermatitis be known?
Wet eczema.

The veterinary surgeon has asked you to bathe a Golden Retriever suffering from acute moist dermatitis. Describe the procedure.

Talk to and reassure the animal.

Ensure that the animal is adequately restrained (Moist dermatitis can be very painful and therefore sedation may be required).

Adorn protective apron and gloves.

Gently clip the hair from the affected area/s using clippers. Make sure the clippers do not overheat since excessive heat and friction could worsen the condition. Ensure that a margin of healthy skin is exposed.

Use a mild antiseptic solution to gently cleanse the area.

Administer drugs according to the veterinary surgeon's instructions (oral antibiotics are usually indicated, topical preparations may be advised).

Ensure that the client is given the correct instructions for home care and drug administration.

What part of the anatomy is affected by labial dermatitis?
The lips.

Give 2 examples of superficial pyodermas and briefly describe each.

Juvenile pustular dermatitis - As its name implies, most often seen in puppies. It is characterised by multiple pustules and yellow scabs, particularly on the ventral abdomen.

Folliculitis - Infection of the hair follicles. It is characterised by the formation of pustules that have a hair protruding. The lesions may assume a ring formation and particularly affect the ventral abdomen.

By what other name might juvenile pustular dermatitis or puppy pyoderma be known?
Impetigo.

Give 2 examples of deep pyodermas and briefly describe each.

Interdigital pyoderma - The paws become swollen and painful, and areas of alopecia and pus exudation are likely to be evident. In severe cases, ulceration and fistulas may result.

Furunculosis - A staphylococcal infection represented by many clumps of pustules, ulcers and fistulas. Lesions are most commonly found on the nose, muzzle, flanks and perineum.

By what other name might interdigital pyoderma be known?
Pododermatitis.

Give an example of a breed of dog that is predisposed to interdigital dermatitis?
The English Bull Terrier.

State 2 medical conditions that are often associated with furunculosis.

Demodicosis.

Hypothyroidism.

Give an example of a breed of dog that is predisposed to anal furunculosis.
The German Shepherd.

What is the treatment of choice for anal furunculosis (perianal fistulae)?
Cryosurgery, after debridement and possible anal sac excision.

What is urticaria?
An acute or chronic allergic skin condition characterised by the recurrent appearance of an eruption of weals causing great irritation.

List 6 possible causes of urticaria.

Drugs or vaccines.

Insect bites.

Stings.

Infection.

Stress.

Certain foods.

What is the name given to a state of hypersensitivity to certain antigens?
Atopy.

*In dogs, state the age range at which atopic dermatitis is most likely to occur.
At 1-3 years of age.

List 5 treatments that may be used in the management of atopic dermatitis.

Corticosteroids.

Antihistamines.

Specially prepared hyposensitivity drugs.

Essential fatty acid supplementation.

Topical shampoos such as colloidal oatmeal every 3 days.

List the 6 most common possible causes of atopic dermatitis.

House dust.

House dust mites.

Pollen.

Fungi.

Danders.

Pollens.

What is meant by an "elimination diet"?
This is a method of diagnosing hypersensitivity to certain types of food. A single protein and carbohydrate source to which the animal has had no previous exposure are fed exclusively for a 6-8 week period. After this period, single food items are reintroduced back into the diet in order to determine which allergens are involved.

State 2 diagnostic tests that may aid the diagnosis of allergic skin disease.

Patch testing.

Intradermal skin testing.

Why should only xylazine or medetomidine be used as sedative drugs prior to intradermal skin testing?
Any other drug may interfere with the test and cause inaccurate results.

When performing intradermal skin testing, 2 other substances are administered in addition to the allergen. What are they?

A positive control - histamine.

A negative control - sterile diluent.

List 5 symptoms of flea allergy dermatitis.

Erythema.

Papules.

Pustules.

Crusts.

Hair loss.

By what other name might feline miliary dermatitis be known?
Miliary eczema.

What is the most common cause of feline miliary dermatitis?
Hypersensitivity to flea saliva or excreta.

What is excoriation?
An abrasion of the skin; often as a result of self-inflicted trauma following conditions such as flea allergy dermatitis.

What is acanthosis nigricans?
A cutaneous reaction characterised by skin thickening, alopecia and excessive pigmentation. The cause may be due to friction, allergy or a hormone imbalance.

What breed of dog is particularly predisposed to acanthosis nigricans?
The Dachshund.

State the 2 most likely causes of canine acne.

Androgen increase at puberty.

Foreign body granulomata (hair and keratin).

What is the name given to the skin disease of cats associated with continual licking, cleaning or hair-pulling, attributed to stress factors or anxiety neurosis?
Psychogenic neurodermatitis (or psychogenic alopecia/dermatitis).

What is the name of the skin disease of cats that may predispose to squamous cell carcinoma?
Solar dermatitis.

By what name is juvenile cellulitis commonly known?
Puppy strangles.

List the prescription diets that may be useful in the management of skin disease.

Hills Z/D Diet.

Waltham Sensitivity Control.

From what food source is the carbohydrate proportion in hypoallergenic diets usually derived?
Rice.

What is meant by "novel ingredients", and when might their use be indicated?
These are ingredients that are not typically used in the pet food industry. Some animals develop an intolerance to certain food stuffs, and the use of novel ingredients means that prior sensitisation to them is unlikely e.g. capolin and tapioca.

Diseases Of The Cutaneous System

Arlo Guthrie — Tue, 21 Apr 2009 05:40:12 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:40:12

QUESTIONS

Note that some of the questions in this section (those marked with an asterisk) are more advanced than required for the final V.N. exams. However, they are of interest to those already qualified, or studying for the Medical Diploma.

Define the following: pruritis, seborrhoea and pyoderma.

What is the term that describes redness of the skin caused by congestion of the capillaries in its lower layers?

* What is the most common pathogen isolated in cases of canine pyoderma?

* List 3 secondary opportunistic bacteria that are commonly associated with Staphylococcus intermedius in cases of canine pyoderma.

What is the general term used to describe the loss of hair from any site and for any reason?

List 5 hormonal diseases that may cause bilaterally symmetrical alopecia.

By what other name might acute moist dermatitis be known?

The veterinary surgeon has asked you to bathe a Golden Retriever suffering from acute moist dermatitis. Describe the procedure.

What part of the anatomy is affected by labial dermatitis?

Give 2 examples of superficial pyodermas and briefly describe each.

By what other name might juvenile pustular dermatitis or puppy pyoderma be known?

Give 2 examples of deep pyodermas and briefly describe each.

By what other name might interdigital pyoderma be known?

Give an example of a breed of dog that is predisposed to interdigital dermatitis?

State 2 medical conditions that are often associated with furunculosis.

Give an example of a breed of dog that is predisposed to anal furunculosis.

What is the treatment of choice for anal furunculosis (perianal fistulae)?

What is urticaria?

List 6 possible causes of urticaria.

What is the name given to a state of hypersensitivity to certain antigens?

* In dogs, state the age range at which atopic dermatitis is most likely to occur.

List 5 treatments that may be used in the management of atopic dermatitis.

List the 6 most common possible causes of atopic dermatitis.

What is meant by an "elimination diet"?

State 2 diagnostic tests that may aid the diagnosis of allergic skin disease.

Why should only xylazine or medetomidine be used as sedative drugs prior to intradermal skin testing?

When performing intradermal skin testing, 2 other substances are administered in addition to the allergen. What are they?

List 5 symptoms of flea allergy dermatitis.

By what other name might feline miliary dermatitis be known?

What is the most common cause of feline miliary dermatitis?

What is excoriation?

What is acanthosis nigricans?

What breed of dog is particularly predisposed to acanthosis nigricans?

State the 2 most likely causes of canine acne.

What is the name given to the skin disease of cats associated with continual licking, cleaning or hair-pulling, attributed to stress factors or anxiety neurosis?

What is the name of the skin disease of cats that may predispose to squamous cell carcinoma?

By what name is juvenile cellulitis commonly known?

List the prescription diets that may be useful in the management of skin disease.

From what food source is the carbohydrate proportion in hypoallergenic diets usually derived?

What is meant by "novel ingredients", and when might their use be indicated?

Diseases Of The Musculo-Skeletal System - Answers

Arlo Guthrie — Tue, 21 Apr 2009 05:38:36 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:38:36

ANSWERS

Note that some of the questions in this section (those marked with an asterisk) are more advanced than required for the final V.N. exams. However, they are of interest to those already qualified, or studying for the Medical Diploma.

State the 2 minerals that must be present in the correct ratio in the diet of a growing animal in order to ensure healthy bone.

Calcium.

Phosphorous.

State the 2 most important vitamins necessary in the correct quantity in the diet of a growing animal to promote healthy bone.

Vitamin A.

Vitamin D.

What disease of bone is associated with an incorrect balance of calcium and phosphorous?
Secondary nutritional hyperparathyroidism.

What is another name for secondary nutritional hyperparathyroidism?
Renal rickets (or rubber jaw).

What is the name of the bone disease of cats associated with hypervitaminosis A?
Cervical spondylitis.

List 5 major canine developmental skeletal diseases.

Hip dysplasia.

OCD.

Wobbler syndrome.

Panosteitis.

Ununited anconeal process.

State the most common canine developmental orthopaedic disease encountered by veterinary surgeons.
Canine hip dysplasia (CHD).

Give 2 examples of dog breeds predisposed to disc protrusion (prolapsed intervertebral disc - PID).

Dachshund.

Pekingese.

Define osteopathy.
Any disease of bone in the skeleton.

*Give an example of a dog breed predisposed to craniomandibular osteopathy.
The West Highland white terrier.

What is osteodystrophy?
Disease of bone during its development and growth.

*What disease of bone is most commonly seen in Great Danes and giant breeds aged 3-6 months?
Metaphyseal osteopathy.

*By what other name might metaphyseal osteopathy be known?
Skeletal scurvy.

*What part of the anatomy in addition to bone is affected by secondary hypertrophic osteopathy (Marie's disease)?
The lungs.

What is the most likely cause of osteomyelitis?
Bacterial infection (usually pyogenic).

What is the name of the disease caused by a deficiency of osteoid due to a disturbance of tissue metabolism (rather than calcium:phosphorous metabolism)?
Osteopenia (osteoporosis).

Define arthritis, and list 6 possible causes.
Arthritis is the inflammation of one or more joints. It is characterised by restricted movement in the joint, pain and swelling. Possible causes:

Excessive wear.

Poor joint conformation.

Post injury/trauma.

Infectious.

Immune mediated.

Nutritional imbalance/deficiency.

What infectious disease may cause arthritis?
Lyme disease.

A dog is presented showing pain, stiffness and joint disuse. The veterinary surgeon suspects arthritis, but wants to rule out other differential diagnoses including tendon injury and osteomyelitis. How could the arthritis diagnosis be confirmed?

Radiography.

Synovial fluid examination and culture.

Give 2 examples of non-steroidal anti-inflammatory drugs (NSAIDs) used in the treatment of non-infectious arthritis.

Metacam (meloxicam).

Rimadyl (carprophen).

Briefly describe DJD.
DJD is short for degenerative joint disease; a progressive condition that leads to the erosion of cartilage and new bone deposits around the joint. German Shepherds are an example of a dog breed predisposed to this condition.

*List 5 procedures/tests that may be performed in order to aid the diagnosis of feline immune-based polyarthritis.

Radiography.

Rheumatoid factor.

Antinuclear antibody.

Synovial fluid analysis.

Synovial membrane biopsy.

What is the most common cause of bursitis?
Trauma; heavy dogs lying down on hard surfaces).

What is the name of the disease caused by a disturbance of endochondrial ossification affecting the growth plates and articular cartilage?
Osteochondrosis (OCD).

State the 4 breeds of dog that are most at risk of OCD.

Great Dane.

Rottweiler.

Labrador retriever.

Newfoundland.

What 2 tissue types are affected by OCD?

Bone.

Cartilage.

State the risk factors for osteochondrosis.

Genetics.

Age.

Gender (males are more likely to develop OCD of the proximal humerus).

Breed.

Calcium excess.

Feeding methods (especially ad-lib feeding).

Excessive weight gain.

What is osteomalacia?
The failure of osteoid tissue to mineralise; a disease of the skeleton caused by inadequate intake of bon-forming elements in the diet or a vitamin D deficiency.

By what name is the juvenile form of osteomalacia known?
Rickets.

What is panosteitis?
Localised excessive formation of bone in young dogs.

List 4 clinical signs of panosteitis.

Shifting lameness.

Recurrent lameness.

Pain associated with long bones.

Pyrexia.

What is the term used to describe a loss of bone density, resulting in bones that are brittle and liable to fracture?
Osteoporosis.

What is the term used to describe inflammation of muscle tissue?
Myositis.

What part of the anatomy is affected in cases of atrophic myositis?
The mouth (the muscles of mastication).

What disease of muscle is characterised by profound muscular weakness induced by exercise, regurgitation, salivation, ulceration of buccal mucosa and distension of the bladder?
Myasthenia gravis.

Give an example of a neoplasm that affects bone.
Osteosarcoma.

What is an osteoma?
A benign tumour of bone.

List general requirements for the nursing of any patient with bone disease.

Ensure rest.

Ensure plenty of deep, comfortable bedding.

Ensure that weight is kept at an optimal level (obesity can cause conditions to worsen).

Ensure that any medication is given at the correct dose, by the correct route and at the correct time.

Ensure that the owner is given the correct instructions for care of the animal at home when discharged.

Diseases Of The Musculo-Skeletal System

Arlo Guthrie — Tue, 21 Apr 2009 05:37:40 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:37:40

QUESTIONS

Note that some of the questions in this section (those marked with an asterisk) are more advanced than required for the final V.N. exams. However, they are of interest to those already qualified, or studying for the Medical Diploma.

State the 2 minerals that must be present in the correct ratio in the diet of a growing animal in order to ensure healthy bone.

State the 2 most important vitamins necessary in the correct quantity in the diet of a growing animal to promote healthy bone.

What disease of bone is associated with an incorrect balance of calcium and phosphorous?

What is another name for secondary nutritional hyperparathyroidism?

What is the name of the bone disease of cats associated with hypervitaminosis A?

List 5 major canine developmental skeletal diseases.

State the most common canine developmental orthopaedic disease encountered by veterinary surgeons.

Give 2 examples of dog breeds predisposed to disc protrusion (prolapsed intervertebral disc - PID).

Define osteopathy.

* Give an example of a dog breed predisposed to craniomandibular osteopathy.

What is osteodystrophy?

* What disease of bone is most commonly seen in Great Danes and giant breeds aged 3-6 months?

* By what other name might metaphyseal osteopathy be known?

* What part of the anatomy in addition to bone is affected by secondary hypertrophic osteopathy (Marie's disease)?

What is the most likely cause of osteomyelitis?

What is the name of the disease caused by a deficiency of osteoid due to a disturbance of tissue metabolism (rather than calcium:phosphorous metabolism)?

Define arthritis, and list 6 possible causes.

What infectious disease may cause arthritis?

A dog is presented showing pain, stiffness and joint disuse. The veterinary surgeon suspects arthritis, but wants to rule out other differential diagnoses including tendon injury and osteomyelitis. How could the arthritis diagnosis be confirmed?

Give 2 examples of non-steroidal anti-inflammatory drugs (NSAIDs) used in the treatment of non-infectious arthritis.

Briefly describe DJD.

* List 5 procedures/tests that may be performed in order to aid the diagnosis of feline immune-based polyarthritis.

What is the most common cause of bursitis?

What is the name of the disease caused by a disturbance of endochondrial ossification affecting the growth plates and articular cartilage?

State the 4 breeds of dog that are most at risk of OCD.

What 2 tissue types are affected by OCD?

State the risk factors for osteochondrosis.

What is osteomalacia?

By what name is the juvenile form of osteomalacia known?

What is panosteitis?

List 4 clinical signs of panosteitis.

What is the term used to describe a loss of bone density, resulting in bones that are brittle and liable to fracture?

What is the term used to describe inflammation of muscle tissue?

What part of the anatomy is affected in cases of atrophic myositis?

What disease of muscle is characterised by profound muscular weakness induced by exercise, regurgitation, salivation, ulceration of buccal mucosa and distension of the bladder?

Give an example of a neoplasm that affects bone.

What is an osteoma?

List general requirements for the nursing of any patient with bone disease.

Diseases Of The Endocrine System - Answers

Arlo Guthrie — Tue, 21 Apr 2009 05:35:42 GMT
Current revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 21/04/2009 06:35:42

ANSWERS

Which hormone is produced in excess in Cushing's disease?
Cortisol.

By what other name might Cushing's disease be known?
Hyperadrenocoticism.

What is the name of the hormone that is released from the pituitary gland and is responsible for stimulating the production of cortisol from the adrenal glands?
Adrenocorticotrophic releasing hormone (ACTH).

List 6 clinical signs of Cushing's disease.

Polyuria/polydipsia.

Alopecia/thin skin/comedomes (keratin and sebum plugs).

Lethargy.

Polyphagia.

Obesity.

Muscle weakness/atrophy.

*Would you expect the following haematology parameters to be raised or lowered in animals suffering from Cushing's disease: eosinophils, neutrophils and lymphocytes?

Eosinophils - lowered.

Neutrophils - raised.

Lymphocytes - lowered.

*Which biochemistry parameters might you expect to display abnormalities in an animal suffering from Cushing's disease?

ALP - raised.

ALT - raised.

Cholesterol - raised.

What is the name of the specific test used to diagnose Cushing's disease?
ACTH stimulation test.

When taking blood for an ACTH stimulation test, a pre and post ACTH sample are required. How long following injection of ACTH should the second blood sample be taken?
1-2 hours. Some vets may take the second sample at 30 minutes after administration.

If an animal has Cushing's disease, would you expect to see an increase or decrease in circulating cortisol following injection of ACTH?
An increase (grossly exaggerated).

What therapy is required following bilateral adrenalectomy?
Lifelong mineralocorticoid therapy.

What is the name of the cytotoxic drug used in the treatment of Cushing's disease?
Trilostane.

In hypoadrenocorticism, insufficient cortisol and aldosterone are produced. By what other name might this disease be known?
Addison's disease.

In which species and sex is Addison's disease most common?
The bitch (usually large breeds).

By what name might acute Addison's be known?
Addisonian crisis.

How do the symptoms of acute and chronic Addison's differ?
The signs of chronic Addison's tend to be vague and non-specific whilst animals with acute Addison's will suffer from vomiting, anorexia, weakness, collapse and shock.

Why are Addisonian animals usually hyponatraemic and hyperkalaemic?
Due to low aldosterone levels.

What is the name of the glucocorticoid supplement used in the treatment of Addison's disease?
Dexamethasone.

What is the name of the mineralocorticoid supplement used in the treatment of Addison's disease?
Fludrocortisone (Forineff).

List 12 clinical signs that may be evident in a hyperthyroid cat.

Weight loss.

Polyphagia.

Hyperactivity.

Restlessness/aggression.

Moderate elevation of body temperature.

Tachycardia (possibly with a variety of cardiac arrhythmias/murmers).

Increased frequency of defecation (abundant bulky stools passed).

Polyuria/polydipsia.

Occasional vomiting.

Panting.

Hyperaemia (reddening of the mucous membranes/skin).

Matted, greasy and unkempt coat.

What tests may be used to aid a diagnosis of feline hyperthyroidism?

Total T4.

Liver enzymes (usually raised in hyperthyroid animals).

ECG.

Palpation of the thyroid glands.

Mediate auscultation of the heart.

What is the name of the drug commonly used to treat hyperthyroidism in cats?
Neo-Mercazole.

What biochemistry blood parameters must be measured for 3 days following thyroidectomy?

Calcium.

Phosphorous.

What drug is commonly used to treat hypothyroidism in dogs?
Soloxine.

Name the 2 types of diabetes insipidus?

Central diabetes insipidus

Nephrogenic diabetes insipidus.

What is the name of the hormone that is deficient in cases of central DI?
Antidiuretic hormone (ADH).

What are the most common signs of DI?
Polyuria and polydipsia.

What urine specific gravity range would you expect to see in an animal suffering from DI?
1.002 to 1.008.

What is the name of the specific test used to diagnose DI?
Water deprivation test.

For how long must water be withheld during preparation for a water deprivation test?
15 hours or if the patient loses more than 5% of their starting body weight.

A water deprivation test should not be performed if what blood biochemistry parameter is elevated?
Blood urea.

*Describe how a water deprivation test is performed.

Preparation - starvation for 12 hours, water withheld for 15 hours.

Bladder emptied by catheterisation first thing in the morning.

Weight of the animal recorded.

Recatheterisation every 2-4 hours and measurement of urine SG and weight taken each time.

STOP when more than 5% of body weight lost or dehydration evident.

Perform ADH response test (if still no concentration - likely nephrogenic DI as the kidney is not responding to the ADH).

If urine becomes concentrated during a water deprivation test, what explanation could you give for the initial low SG?
The animal is probably a compulsive drinker (perhaps related to stress).

*By what other name might compulsive drinking due to stress be known?
Pyschogenic polydipsia.

What treatment might be used in cases of DI?
Administration of ADH by injection or nasal drops (Desmopressin). Chlorothiazide diuretics and a low sodium diet may help).

Briefly describe the 2 types of diabetes mellitus.

Type 1 - Insulin dependent: insufficient insulin is secreted in response to hyperglycaemia.

Type 2 - Non-insulin dependent: Animals become resistant to the effects of insulin (common in man, rare in the dog but probably more common in the cat).

List the 4 main functions of insulin.

Slows down glucogenesis (glucose creation) in the liver.

Slows down glycogenolysis (breakdown of glycogen) in the liver.

Slows down lipid and protein catabolism.

Helps the cells to absorb glucose.

Which organ produces insulin?
The pancreas.

What is often the first sign of DM?
Polydipsia.

List 4 conditions that may precipitate DM.

Obesity.

Pancreatitis.

Oestrus.

Drugs (glucocorticoids and megoestrol acetate).

Why might an animal suffering from DM show hepatomegally?
As a result of increased fat storage.

What condition of the eye is commonly seen in diabetic animals?
Cataracts.

What causes ketotic breath?
Acetone.

Why is regular insulin normally only used in the treatment of ketoacidotic dogs?
It has a rapid onset (30 minutes).

What is the name of the insulin that has a maximum action of 14-20 hours and duration of 24-36 hours?
PZI insulin.

Where should insulin be stored?
The refrigerator.

List 3 signs of hypoglycaemia.

Muscle weakness.

Twitching/fitting.

Lethargy.

Recumbency.

What action should be taken in the case of hypoglycaemia?
Initially, oral administration of Hypostop. If Hypostop is unavailable any sugary substance such as honey or jam may be substituted. If no improvement is observed within 30 minutes, intravenous dextrose fluids may be required. Insulin dosage will need to be decreased.

*Why do animals with ketoacidosis vomit?
Due to excess ketones that stimulate the emetic centre of the brain.

Why are diabetic cats often more difficult to stabilise than dogs?

Collecting a urine sample may prove very difficult for owners.

Regulating food intake is often difficult in multicat households.

Exercise regulation is difficult in cats that have access to the outdoors.

Cats may resent injection more than dogs and may be more difficult to restrain.

List 5 possible causes of hyperglycaemia in a diabetic dog.

Inadequate dosage of insulin

Excessive food consumption.

Obesity.

Infection.

During the period following the season in bitches.

List 3 possible causes of hypoglycaemia in a diabetic dog.

Insulin overdose.

Lack of food.

Over-exercise.

Why should special care be taken when using Caninsulin?
Caninsulin is administered with special syringes that have a different scale to the international units that are used with other types of insulin.

Give an example of a prescription diet suitable more feeding a diabetic dog of normal weight.
Hills Canine W/D, or any other high fibre diet e.g. Chappie.