Physiology Of Anaesthesia & Analgesia

Arlo Guthrie — Tue, 21 Apr 2009 11:10:54 GMT

Current Revision posted to Revision Guide For Student Nurses - Part 2 by Arlo Guthrie on 4/21/2009 11:10:54 AM

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.