Use of Nirtous oxide for small animals

RE: Use of Nirtous oxide for small animals

Krissy — Thu, 01 Feb 2018 15:08:43 GMT

Hi susanna

You don’t have any access to the Carol Hoy paper do you? I’ve only found it to purchance for £65.00 thought it was worth an ask, really appreciate every ones help

RE: Use of Nirtous oxide for small animals

Krissy — Thu, 01 Feb 2018 14:51:55 GMT

Thanks all again for your input, we have a new multi parameter about to be installed with capnography so will definitely as about the gas thing, felt more comfortable and used 50:50 today on ADE for a WHWT definitely help when inside the joint, still needed a smidge more methadone iv at the beginning, and switch off once implant placed, seemed to work well thank you again, hopefully will get more confident the more we use it

RE: Use of Nirtous oxide for small animals

Krissy — Thu, 01 Feb 2018 14:43:58 GMT

Thank you this is great

RE: Use of Nirtous oxide for small animals

Sal the 1st — Thu, 01 Feb 2018 08:42:25 GMT

was pleased to see this question - I have used nitrous in the past and found it gave a really smooth anaesthetic especially for orthos but was told I was old fashioned used to use it as above poster 50:50 increasing to 2:1 if warranted.

RE: Use of Nirtous oxide for small animals

Susanna Taylor — Thu, 01 Feb 2018 02:39:58 GMT

I also liked using Nitrous when i had access to it. Its a quick and cheap form of additional multimodal analgesia. Few pointers:

Rarely works for analgesia clinically below a 50%. I always start at 1:1 (50/50 with O2), and see if i get the desired analgesic effect

If 50/50 is not working, you can increase to a maximium of 2:1 (66% with 33% oxygen). If you go greater then this you risk hypoxia

Nitrous WILL accumulate in low flow systems (i.e. circles and ADE in circle format, with rates <1.5L). You have a few options to combat this:

1- just use the circle at higher flows, say 2L nitrous and 1L O2. You loose the benefits of the circle but play safe

2- Keep low flow but 'flush' the system every 15min or so with higher flow rates for a few minutes.

3- Use gas/agent monitoring which tells you precise levels of inspired and expired gases so you can accurately titrate (this can be expense to purchase, but some capnographs do have the function, especially old humans one, and they might just need to be calibrated to use it)

Always monitor closely for hypoxia with higher levels - this is a time to tend to believe your pulse ox if its saying 90%. The capno wont warn you about hypoxia, and the patient wont necessarily be rebreathing CO2 or hypercapnic just because its breathing high N2O

Make sure you know how to set your flowmeter correctly to get the correct ratio. I.e top vs middle of bobbin

Dont use nitrous on any 'gases' cases - GDV, endoscopy, pneumothorax or poss subclinical pneumo (post thoracic trauma, RTA etc, even if its for a fracture repair!)

Make sure the nitrous has been off for at least 10min before disconnecting at the end of the op, or else you risk diffusion hypoxia.

My old colleague Carol Hoy published an article in one of the nursing Journals a few years back on N20, worth a search for it!

RE: Use of Nirtous oxide for small animals

Nick Shackleton — Wed, 31 Jan 2018 17:18:05 GMT

I’ve only every used it with non rebreathing curcuits and standard circles. I’d maybe contact the makers of the ADE. I cant see a problem, but best to check with them. Always use 50/50 ratio. Should always have capnography On patients that your using nitrous on

RE: Use of Nirtous oxide for small animals

Krissy — Wed, 31 Jan 2018 14:25:12 GMT

Thank you all for your help, text us great, you guys that have used it, which circuits do you use it with? I’ve used it with an open circle but never with ADE which is what we now have, I’m worried about the really low flow rates of Humphrey ADE and whether this is something I need to account for with the flow rates, thank you all again for your help.

RE: Use of Nirtous oxide for small animals

V E S — Wed, 31 Jan 2018 13:06:53 GMT

Heres a photo of the passage in the BSAVA Textbook of Veterinary Nursing 5th Edition (2011) - not most up to date but good info still. I do not use Nitrous at all, I'm not sure my practice even has it!! But we are referral and have access to many other pain relief/anaesthetic agents that first opinion might not. I personally worry about hypoxia and we deal with patients needing endoscopy (which requires filling cavities such as the stomach with air) and those with pneumothorax, so not much reason to use it. It's all down to personal preference though :-)

RE: Use of Nirtous oxide for small animals

apache — Tue, 30 Jan 2018 23:10:24 GMT

As an aside, methoxyflurane is now licenced in the UK for human use and is used as an analgesic, particularly in the pre-hospital world:

https://www.penthrox.co.uk/hp/information/introducing-penthrox/

http://www.ambulancetoday.co.uk/news-item/new-hand-held-emergency-pain-relief-inhaler-launched-in-the-uk/

(as is 50% nitrous with 50% oxygen as Entonox)

RE: Use of Nirtous oxide for small animals

Nick Shackleton — Tue, 30 Jan 2018 19:40:55 GMT

The following is taken from liz Welsh’s anaesthesia for nurses book. I regularly use nitrous especially in ortho cases or bitch spays. Just avoid in those patients with gas filled structures. Such as GDVs as nitrous will rush into these areas and exacerbate things.