Bradycardia in pug

RE: Bradycardia in pug

chansta — Tue, 20 Sep 2022 09:30:51 GMT

Hi Bexxy123,

It’s incredible how one rough GA can knock our confidence, think we all know the feeling…

I’d agree with the above comments and also remember the drugs used as premed (i.e. domitor) has a big impact on the cardiovascular system. Knowing the patients HR before premed is helpful. So while the BP was around 110mmHg (assume this is the mean?), and heart rate is low as a reflex bradycardia due to increased vascular tone, sounds like the patient is reacting to the surgeon pulling on ligaments etc. If the patients depth of anaesthesia was sufficient (eyes ventromedial, relaxed jaw tone) them the changes is RR are probably related to the surgical stimulation and suggests the patient needs more pain relief. Paracetamol helpful or a low dose ketamine IM would help too (remembering this may increase BP, HR and anaesthetic depth too) or a top up of methadone could help. Alternatively you could ask you’re vet to be a little more gentle

Cyanotic mm should not be seen on patient breathing close to 100% oxygen. Capnograph would be very useful to know if patient is rebreathing X

RE: Bradycardia in pug

apache — Sat, 10 Sep 2022 20:58:28 GMT

[quote userid="37706" url="~/001/veterinary-nurse-clinical/small-animal/anaesthesia/f/discussions/32345/bradycardia-in-pug/177865#177865"]Drug recommendations to a nurse are always so difficult. A lot of vets are extremely anti giving of NSAIDs prior to anaesthesia and rather give it afterwards due to poorer perfusion during the anaesthetic and not wanting to put too much strain on the kidneys. And depending on the relationship you have with your vet, any request for drugs or recommendations may fall on deaf ears.[/quote]

In our practice I think all the vets are receptive to drug input from the nurses, I'm very happy to discuss timing of NSAIDs etc. In an anaesthetic such as this I'd be surprised if the nurse didn't suggest paracetamol/atropine TBH. I'd hate to work in an environment where that wasn't the case - even though the final decision lies with the vet.

RE: Bradycardia in pug

bexxy123 — Sat, 10 Sep 2022 09:13:37 GMT

This is all great thank you, I need a reminder of stuff i once knew but have replaced in my brain store with baby related things-- (been on maternity leave for 10 months) so getting those brain cells working again is exactly what I need thank you.

There's a lot of things I would like to improve at my new practice and this will help me get everyone on board. Thank you

RE: Bradycardia in pug

Alice Weaver — Sat, 10 Sep 2022 08:30:19 GMT

Here is the link to the Clinician’s Brief article: https://www.cliniciansbrief.com/article/perioperative-management-brachycephalic-dogs

if you haven’t used it before, you need to create a login but it’s free.

The next Anaesthetic Emergencies CPD is in Novemeber: vetcpd.co.uk/.../

RE: Bradycardia in pug

Alice Weaver — Sat, 10 Sep 2022 08:23:52 GMT

Everything apache has said I totally agree with! I’m just going to be an annoying devil’s advocate. I’m no expert, but I definitely feel like anaesthesia becomes more of an ‘art’ as you become more experienced- you could ask multiple people their opinion and you could get conflicting answers, but it’s the nuance that makes the difference!

If capnography was in use, it may have shown that the patient wasn’t rebreathing, so the 3.5L/min FGF may have been appropriate. However, we don’t have information on ETCO2. I guess if OP hasn’t mentioned it, you can conclude that it wasn’t being monitored, in which case I agree that FGF rate should have been higher.

I’m always wary of using a lack/mini with brachy breeds as they are less suitable for IPPV. OP has mentioned IPPV was used in which case the Ayres circuit is a better choice.

I’m quite concerned about the mention of mm being ‘slightly blue’! The only change in mm colour I would accept during anaesthesia in an otherwise healthy patient is slightly paler pink- and even then mainly in cats, and depending on what drugs have been given and other parameters such as peripheral pulse/CRT/BP. Once mm are cyanotic then true SPO2 is definitely <90%, and is an indication of hypoxaemia. I would check that your ‘pleth’ waveform is as it should be in these instances, as I would wager that this SPO2 reading is inaccurate. Personally, SPO2 is not my top priority during an anaesthetic- I would be a lot more likely to concentrate on ETCO2 or BP; or indeed good ol’ pulse rate, resp rate and reflexes. If your eyes are cyanosis, rely on this and not on an SPO2 number!

Drug recommendations to a nurse are always so difficult. A lot of vets are extremely anti giving of NSAIDs prior to anaesthesia and rather give it afterwards due to poorer perfusion during the anaesthetic and not wanting to put too much strain on the kidneys. And depending on the relationship you have with your vet, any request for drugs or recommendations may fall on deaf ears. Hopefully however, if you are giving your vet a clear picture of what your patient is doing (ie becoming cyanotic and bradycardic and ‘huffing’) and that everything you are doing (ie IPPV, turning iso up/down) isn’t working, they will understand that something needs to be done and will give atropine or some pain relief. The options here are endless and depend on what you have available in your practice; vets I work with use local anaesthetic and ketamine for example.

I recently followed the Anaesthetic Monitoring and then Anaesthetic Emergencies online CPD with VetCPD, which were so useful and I would highly recommend. There is a great article on Clinician’s Brief called Perioperative Management of Brachycephalic Dogs that would be worth a read- and show it to your vet as well, as there are drug decision-making suggestions in it that aren’t within the remit of a nurse.

RE: Bradycardia in pug

bexxy123 — Sat, 10 Sep 2022 07:49:52 GMT

Thank you for that- so I've just moved practices as everything is different, the monitor how shall we say "needs updating" so I was going in a little blind- all the premeds are different, circuits are different- basically everything is different and I'm so keen to make improvements where possible. I've never really had trouble with anaesthetics before as for the last 10 years worked with the whole picture in front of me using a multi parameter and physical findings so was totally thrown not having part of the picture to work from. Definitely a learning experience for me!!! I've used methadone with a full multi modal approach with paracetamol, ketamine, meloxicom, acp and methadone In bitch spays and have never really had trouble. Every day is a school day!!!!

Thanks for your help- I have felt so confident in my work for years for the first ga at a new practice to throw me!!!

RE: Bradycardia in pug

apache — Fri, 09 Sep 2022 22:46:53 GMT

Many things, it's vital we get the NSAID in and active before causing pain, either at admit/pre-med. Personally not a fan of methadone, but lots like it. If something is showing signs of pain then we would always give IV paracetamol, I find it very anaesthetic sparing.

What was HR before starting, and what did the CO2 look like? How heavy?

I would absolutely have given high dose atropine with that HR.

If we work backwards off the 3.5l/min (CF 2.5, RR 25, then minute volume would be 56ml/min, and using 15ml/kg as tidal volume, makes the dog 3.7kg), I think the O2 flow was too low, giving high CO2 that the dog was trying to get rid of. If the dog was a more realistic 8kg then the O2 needed to be double where you had it, with that RR, or use a mini lack where it would have been fine. Capnograph is king here.

Please look at timing of NSAIDs and use of other analgesics, it's not all about the methadone.

[We found much worse anaesthetics with methadone, that I don't use it routinely]

RE: Bradycardia in pug

bexxy123 — Fri, 09 Sep 2022 07:23:14 GMT

Also sp02 was 98/99%