Anaesthesia for dog with unknown hepatopathy

RE: Anaesthesia for dog with unknown hepatopathy

Beats — Mon, 18 Jul 2016 00:27:22 GMT

[quote user="Stephanie Fursland"]

Are there any protocols to specifically use or avoid? (my normal dental protocol is ACP+methadone, propofol, lidocaine blocks). I found it hard to quantify the 'increased anaesthetic risk' to the owner as his liver function (as far as we know) isn't impaired....

Thanks :-)

[/quote]

Below is opinion of a lonesome GP for what it's worth ;-)

I would drop the acp personally (midazolam 0.2mg/kg IM if genuinely required in addition to 0.3mg/kg methadone IM as pre-med based on patient's demeanour, but I personally avoid as much polypharmacy as can if any query over liver metabolism and would prefer to just give the opioid) and wouldn't give NSAID pre-op and would limit lidocaine dose to 2mg/kg (all of which are probably overcautious reactions to high ALKP on pre-op blds), otherwise fine.

As the risk is not high (I don't think it's higher than the average older dental dog that you do every week) and whilst it's an elective procedure needs done at some point anyway, I'd not pursue the source of the elevated ALKP but put whatever resources into a well-managed, well-monitored GA instead.

As such, if I'm trying to mitigate the, admittedly very low anticipated anesthetic risk, I would:

1) wheel out whatever monitoring equipment (capnography, BP, ECG, pulse oximetry) I might have access to and use it to supplement a dedicated individual monitoring the patient.

2) I'd pre-oxygenate, or at least supplement O2 during induction with propofol (patiently to effect) through an iv cannula.

3) I'd minimise pre-op stress (EMLA cream if considered helpful, avoiding unecessary fear)

4) Give iv fluids at 5ml/kg/hr assuming no query over heart.

5) Avoid hypothermia or at least make attempt to minimise.

6) Keep anesthetic length to under an hour and do early in day to allow plenty of recovery time before going home.

7) Monitor in recovery.

RE: Anaesthesia for dog with unknown hepatopathy

Kate Richardson — Sun, 17 Jul 2016 22:40:24 GMT

I always ask a) is the dog/cat eating/drinking/peeing/pooing normally and essentially behaving normally and b) how essential is the procedure I am planning. if the answer to a) and b) is yes then general bodily function is more than likely to cope with an anaesthetic and I would rather spend money on supportive things such as fluids and proceed with an accepted risk level. I have rarely had a bad outcome and more commonly have very happy owners who feel that their pet is actually happier post procedure than before. Really about the only thing that seriously concerns me would be an anaemic animal as even mild blood loss can tip these over the edge; chronic anaemia patients are often coping very well with severe anaemia due to their coping mechanisms, hence the stories of 'my last cat had a dental and died 3 days later'. But if these animals had had their dental disease addressed much earlier..... but a pre op PCV isn't expensive

RE: Anaesthesia for dog with unknown hepatopathy

James Laidlaw — Sun, 17 Jul 2016 22:26:34 GMT

I always like to point out to owners that by "not getting a diagnosis" we may be "ruling out a number of significant illnesses" - and which they would prefer to have!

Also it's not your fault that they didn't carry out the procedure when these bloods were relevant one year ago - and "repeating the bloods" can be somewhat euphemistically reworded as "pre-anaesthetic testing" and then incorporated into the procedure, so that it isn't viewed as going down the same old road. If people think they're doing the same things over again they don't see the value in it, but if they understand the re-testing is to ensure relevance and safe practice for the current planned procedure then that often makes sense to them.

RE: Anaesthesia for dog with unknown hepatopathy

Robin Grimmer — Sun, 17 Jul 2016 22:17:32 GMT

I'd put money on Cushings!

RE: Anaesthesia for dog with unknown hepatopathy

Stephanie Wellings — Sun, 17 Jul 2016 21:04:12 GMT

I agree about the 'putting off the dental' thing - if it was a painful infected ear/tail/limb we would be doing something about it! Probably we would regard it as more important to promptly treat in a compromised patient.

I did think Cushings from the lab results and consider doing a low dose dex test when the abnormalities were picked up, but clinically he wasn't Cushings-looking and no PUPD so we abandoned that line of enquiry after the ACTH stim - I did wonder about repeating it now a year down the line, but I am a bit mindful of costs - the owner is unlikely to want to repeat all the investigations that were done last year (not exactly thrilled about us not getting a diagnosis then)...

RE: Anaesthesia for dog with unknown hepatopathy

Kate Richardson — Sun, 17 Jul 2016 19:24:16 GMT

as an addition, even if liver function was mildly impaired, I would still go ahead, if I felt the dental disease was causing significant discomfort as I'd be 99% certain the dog would feel better afterwards so the risk would be far outweighed by the benefit.

Do you suspect the dog is actually Cushingoid, despite the initial acth stim result?

RE: Anaesthesia for dog with unknown hepatopathy

Kate Richardson — Sun, 17 Jul 2016 19:21:32 GMT

I would go ahead, use as low doses of everything you can, iv fluids peri op, but I honestly wouldn't be overly concerned if liver function is ok. I agree with Emily, worth checking coags if you can, but if the owner declines, then treat the dog. It's one of my major annoyances, seeing animals with advanced dental disease which have repeatedly been put off by vets too scared to proceed. Make the owner aware of the risks, as usual, but I wouldn't say it was massively more risky, and the main thing is the dog will feel better afterwards.

RE: Anaesthesia for dog with unknown hepatopathy

Emily Rainbow — Sun, 17 Jul 2016 15:30:01 GMT

I'd prob check clotting beforehand if extractions probable.

RE: Anaesthesia for dog with unknown hepatopathy

Iain Richards — Sun, 17 Jul 2016 14:18:24 GMT

I'll await correction from a lab based vet, but by ALP - presumably Alkaine Phosphatase - although it refelcts biliary damage, it's a common enzyme, so it might be coming from the teeth itself. You've established the liver is normal looking and functioning, so carry on with your normal protocol.