inhalation anaesthesia calculations

Re: inhalation anaesthesia calculations

Gillian Mostyn — Thu, 23 Apr 2009 23:45:23 GMT

Eh? Should I be doing that? We just change the valves ourselves annually - they are pretty user-servicable.

Re: inhalation anaesthesia calculations

louiseRVN — Thu, 23 Apr 2009 19:52:44 GMT

I agree the only annoying thing is having to service them!!!!!!!!!

Re: inhalation anaesthesia calculations

Claire Cameron — Wed, 22 Apr 2009 16:15:32 GMT

[quote user="STRVN"]

[quote user="Gillian Mostyn"]

Get a Humphrey ADE. Life becomes oh-so-simple!

[/quote]

Totally agree, they are the best, I wish everwhere I go had them.

[/quote]

Yup!!!!!

Re: inhalation anaesthesia calculations

Sandra Taylor RVN, MBVNA — Sat, 11 Apr 2009 14:14:32 GMT

[quote user="Gillian Mostyn"]

Get a Humphrey ADE. Life becomes oh-so-simple!

[/quote]

Totally agree, they are the best, I wish everwhere I go had them.

Re: inhalation anaesthesia calculations

Gillian Mostyn — Sat, 11 Apr 2009 14:12:37 GMT

due to its nifty ability to reuse some of the expired air, flow rates are:

600ml for small cats

1l for large cats & dogs < 10kg, no soda lime canister

1l for dogs > 10kg, using soda lime canister

You never need to use more than 1l flow. Obviously reservoir bag sizes increase though.

I love ours. IPPV is easier too - just hold down a small 'peg' with a finger rather than screwing a valve down. Also prevents accidentally forgetting to unscrew it!!!

I saw Mr Humphrey lecture a few years ago and have been a fan ever since!

Re: inhalation anaesthesia calculations

Freckle — Fri, 10 Apr 2009 22:06:33 GMT

there was one of those at a practice i used to work in, but i was never told the flow rates etc - can anyone fill me in?

Re: inhalation anaesthesia calculations

Gillian Mostyn — Fri, 10 Apr 2009 20:57:03 GMT

Get a Humphrey ADE. Life becomes oh-so-simple!

Re: inhalation anaesthesia calculations

dinkyd — Fri, 10 Apr 2009 20:33:25 GMT

yep

Re: inhalation anaesthesia calculations

Emily Hibbs — Thu, 09 Apr 2009 18:33:02 GMT

I was taught at college that the circuit factor for a Bain and T-Piece was 2.5-3 and not 2-3?! Anyone else taught this?

Re: inhalation anaesthesia calculations

Amy White — Thu, 09 Apr 2009 18:24:08 GMT

thanks everyone, it's all come flooding back to me now!

Re: inhalation anaesthesia calculations

Nick Shackleton — Wed, 08 Apr 2009 17:46:36 GMT

you require the minute volume to work out fresh gas flow rates

Minute volume = tidal volume X resp rate

Flow rate = minute volume X circuit factor

Circuit factors are as follows:

T-Piece: 2.0 - 3.0 (Patients <8kg)
Bain: 2.0 - 3.0 (Patients 8 - 30Kg)
Circle: 1.0 (Patients >15kg) (requires higher initial fresh gas flow rate)
Lack & Magill: 1.0 - 1.5 (Patients 8 - 60kg)
To & Fro: 1.0 (Patients >15kg) (requires higher initial fresh gas flow rate)

If you have capnography (ie able to monitor inspired flow rates), it is safe to reduce the fresh gas flow rate, we usually only go as low as 1 litre but you can go lower

Re: inhalation anaesthesia calculations

amanda schulz — Wed, 08 Apr 2009 14:13:42 GMT

Example 30kg Labrador

has a tidal volume of 10ml / kg = 10x30=300ml

Example 4 kg cat

has a tidal volume of 15ml / kg = 15x4 = 60ml

Re: inhalation anaesthesia calculations

amanda schulz — Wed, 08 Apr 2009 14:09:07 GMT

Hi Amy

(To recap) TIDAL VOLUME is the volume of air that goes in and out with each breath.

For patients weighing LESS THAN 10kg, tidal volume is estimated at 15ml/kg.

For patients weighing MORE THAN 10kg, tidal volume is estimated at 10ml/kg.

Hope this helps.

Amanda Schulz