Anaesthesia calculations....

Re: Anaesthesia calculations....

SharonSP — Fri, 23 Apr 2010 22:29:17 GMT

[quote user="samz60020@hotmail.com"]

In my pracs recently they set the resp rate at the pre anaesthetic rate X

[/quote]

Yes, that's correct, the RCVS OSCE provides a pre anaesthetic respiratory rate.

Re: Anaesthesia calculations....

Sammyannieantha — Sat, 27 Mar 2010 20:43:07 GMT

In my pracs recently they set the resp rate at the pre anaesthetic rate X

Re: Anaesthesia calculations....

emvn80 — Thu, 04 Feb 2010 16:14:08 GMT

Eg.

a 15kg dog on a Bain..

If RR was 10bpm, assumming TV of 10ml/kg then... TV= 150ml

MV would be TV X RR = 150 x 10 = 1500ml

CF for Bain is approx 2.5-3.0 x MV so..

2.5 x 1500ml = 3750ml/min or 3.7 L/min, however if the RR inc from 10-20 then the MV would incr to 150 x 20 = 3000ml, therefore the FGF would be 7500ml/min or 7.5l/min!!!!

This also demonstrates how uneconimal a Bain is and how much better a Lack or magill would be or a circle!!!! If you have a capnograph you can try reducing your FGF to see if you get rebreathing and often you can get away with less but you can only do that if you have a capnograph!

Re: Anaesthesia calculations....

emvn80 — Thu, 04 Feb 2010 16:08:05 GMT

sorry to get all anally retentive but this is quite important!!

To start with (ie when calculating rough FGF prior to induction you should use the conscious RR to calculate MV.

But remember then to readjust your FGF as the patients RR changes under anaesthesia... For example if a patients RR in it's kennel was 10bpm but during sx the RR suddenly increased to 20bpm, then your MV would double, therefore your FGF would double. This is why it is so important to always accurately calculate fresh gas flows based on the patients RR AT THE TIME and adjust your FGF as nec. All nurses ahould be able to do this with every circuit at the start of every anaesthetic and be able to adjust the FGF as required. This is especially important if you do not have a capnograph as you will have no other way of knowing if you are supplying adequate FGF to flush out the CO2 from the system.

I hope this helps, try a calculation and you'll see what I mean

Remember the function of the circuit is to suuply oxygen, anaes agent and to remove CO2. In rebreathing circuits the sodalime removes the co2 but in non-rebreathing circuits it is the FGF that flushes out the CO2.

This obviously only applies to non-rebreathing circuits

Re: Anaesthesia calculations....

Vicky RVN — Sun, 31 Jan 2010 16:37:12 GMT

Yeah i've seen others on youtube

Re: Anaesthesia calculations....

Nick Shackleton — Sun, 31 Jan 2010 16:34:02 GMT

[quote user="Vicky SVN"]

I love the amateur transplants! Makes me laugh every time!

[/quote]

you seen any of there other stuff vick???

Re: Anaesthesia calculations....

Vicky RVN — Sun, 31 Jan 2010 16:33:09 GMT

I love the amateur transplants! Makes me laugh every time!

Re: Anaesthesia calculations....

Nick Shackleton — Sun, 31 Jan 2010 10:38:20 GMT

thought this was quite appropriate!!!

www.youtube.com/watch

Re: Anaesthesia calculations....

Maisy — Sun, 31 Jan 2010 08:39:32 GMT

Yep, work out calculations based on conscious parameters first.

Re: Anaesthesia calculations....

Laura Ringsell — Sun, 31 Jan 2010 06:46:06 GMT

I always start with a concious rate and then adjust through the anaesthetic but also hve my own minimums - i.e I have never felt comfortable running the circle below 1L. Sometimes a RR will be faster during surgery so surly the flow rate needs to reflect that ?

Re: Anaesthesia calculations....

Nick Shackleton — Fri, 29 Jan 2010 09:35:28 GMT

I would say concious....

Re: Anaesthesia calculations....

Vicky RVN — Fri, 29 Jan 2010 09:04:48 GMT

College told us yesterday to work it out on RR you take when patient admitted, so conscious. Thinking about it, if you did it when they were asleep (when RR is lower) you'd be not giving them enough fresh gas? I could be wrong though, just how i see it!

Re: Anaesthesia calculations....

Claire Cameron — Thu, 28 Jan 2010 13:02:48 GMT

[quote user="Emma Forde"]

Just a quickie.....

When working out minute volume do you use the resp rate of the animal prior to anaesthesia or do you base it on the resp rate of the animal when anaethetised?

[/quote]

I always calculate on a conscious patient as resp rates will be abnormal when anaesthetised

Re: Anaesthesia calculations....

chanel clydesdale — Thu, 28 Jan 2010 10:59:41 GMT

sorry i thought you meant to get the initial minute volume. You should always taker the initial from the conscious patient but as that changes during anaesthesia then you need to re calculate. thats whats in my college noties anyway...

Re: Anaesthesia calculations....

Emma Forde RVN — Thu, 28 Jan 2010 07:28:42 GMT

Thankyou, I too do it based on the RR of an anaethatised animal. My logic is that it is based on the requirements at that time.

Re: Anaesthesia calculations....

les punton — Wed, 27 Jan 2010 21:01:32 GMT

Im sure that when I done my exams I done when its anaesthetised, which was in front of external verifer so Iv always done it this way.

Re: Anaesthesia calculations....

Honeybadger — Wed, 27 Jan 2010 20:55:16 GMT

I have always based it on the RR of the anaesthitised animal. I thought the oxygen requirements would vary accoridng to the varying RR of the patient. I could be wrong though. I've never seen it specified in any textbooks.

Re: Anaesthesia calculations....

chanel clydesdale — Wed, 27 Jan 2010 20:13:14 GMT

you use the resp rate of the conscious animal and multiply that by the tidal volume i think? x