Should there be a minimum evidence base for surgery?

RE: Should there be a minimum evidence base for surgery?

Arlo Guthrie — Thu, 27 Jun 2024 09:05:48 GMT

[quote userid="8958" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244950#244950"]General practioners don't do these?[/quote]

Not sure if it matters who the surgery is performed by! But clearly not worth it for vanishing rare stuff, and if there are no other surgical techniques other than cruciates which would bear analysis, then for sure, it is a numpty idea!

[quote userid="8958" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244950#244950"]Sorry Arlo, in my opinion, it's just a non starter[/quote]

No need to apologise .. it was only a thought, and I am not remotely offended if it was a rubbish idea, plenty of mine are!

RE: Should there be a minimum evidence base for surgery?

Neil Wheadon — Thu, 27 Jun 2024 08:53:34 GMT

[quote userid="2100" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244949#244949"]I think I misunderstood your point, and you were actually saying that trials of surgery would have so many factors to take into account. Which is true, but surely that is no different to the Cruciate Registry [/quote]

Cruciate surgery is an outlyer in surgical techniques.

You usually operate of younger, fitter animals, so there are no co-morbidities

There is enough case material to make a proper comparison

When specialists do surgery for cruciates, they do select. If there is any infection present, they will ask that this is controlled befoe surgery is undertaken. (This is very similar to my mother where her anaemia, needed to be addressed first)

There are a number of proven techniques, that you can compare across.

I can honestly think of no other surgical technique, which would allow a proper detailed comparison. The only one maybe are ears, where you could compare a lateral wall resection to a total ablation, but they really are different types of operation. You could do a comparison between a lateral wall and putting steroid drops down or controlling the allergy, but this is like comparing apples with pears.

[quote userid="2100" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244949#244949"]Perhaps certain cardiac procedures? [/quote]

General practioners don't do these? They are vanishingly rare in reality, so statistics would be skewed and co-morbidities would play a part

Sorry Arlo, in my opinion, it's just a non starter

Neil

RE: Should there be a minimum evidence base for surgery?

Arlo Guthrie — Thu, 27 Jun 2024 07:57:55 GMT

[quote userid="8958" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244937#244937"]

Arlo Guthrie said:
Hi Neil, to be fair, I wasn't talking about something which defines which patients are suitable or not, but just trying think of ways that owners could be helped to make a more evidence-based decision, especially in the current financial (and scientific) climate when there must surely be a greater need to justify the expense of increasingly expensive procedures.

I respectively disagree.

To make any proper comparison there are plenty of other factors that need to be taken into account, age and sex are obvious. However animals will have Co morbidities and these can only be ascertained by additional tests.

[/quote]

Sorry for slow reply ... been having a bad week. Other daughter had to have her appendix out (less than three weeks after having knee surgery after a little child jumped on her leg in the pub). Then yesterday I kerbed one of the wheels on my car, just a few weeks after I had done exactly the same thing. Expensive mistake.

Anyway Neil Wheadon - I am not sure I understand your point. I thought that because of the comparison with your mum, you were saying that I was proposing a system where suitability for surgery was based both on how effective the surgery had been proven to be, AND whether the patient was suitable (ie not too old).

I think I misunderstood your point, and you were actually saying that trials of surgery would have so many factors to take into account. Which is true, but surely that is no different to the Cruciate Registry

But then I suppose the question is whether there are any other procedures where the outcome is so variable (or needs to be measured over the long term), that it would be useful for there to be something like the Cruciate Registry. I mean, you wouldnt need it for a lump removal. Perhaps certain cardiac procedures?

RE: Should there be a minimum evidence base for surgery?

Beats — Wed, 26 Jun 2024 11:07:47 GMT

Sometimes I try to think if this dog or cat in front of me could make an informed choice what would it choose.

RE: Should there be a minimum evidence base for surgery?

Stigen — Wed, 26 Jun 2024 10:46:47 GMT

[quote userid="12375" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244945#244945"]what really struck me was how hard it really is to know for sure whether the treatment we recommend is actually effective. [/quote]

i Agree. Lately I have had multiple dogs where I had them in for dental descaling, but then on routine mouth x-rays found remaining roots after previously fractured teeth. The gumline has long since grown over the area and looks fine. But per advice I have opened up the gumline and went digging for those roots. It has usually been really hard to get those out, and lots of iatrogenic trauma to both soft tissue and the bony structures, and lots of pain and long recovery. And I feel bad about it, cause the dog showed no signs of pain before I did that, and the area looked perfectly fine.

RE: Should there be a minimum evidence base for surgery?

Alastair Welch — Wed, 26 Jun 2024 07:29:44 GMT

Alternatively the cat developed OA as a result of the instability of its knee.

In common with lots of treatments in veterinary medicine I suspect there is not sufficient or sufficiently robust evidence to guide you either way.

I recall having a the results of a 10 year prospective study into cruciate rupture in people presented at ESVOT about 15 years ago:

big numbers, solid diagnosis, good follow up etc. In terms of outcomes there appeared no difference between those opting for surgery and those undergoing intensive physio to try and help re-stabilise the knee.
Ignoring the specific problem in the study what really struck me was how hard it really is to know for sure whether the treatment we recommend is actually effective.

RE: Should there be a minimum evidence base for surgery?

Stigen — Wed, 26 Jun 2024 07:04:53 GMT

[quote userid="2100" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244936#244936"]

Ha. There you go! I'd forgotten about that one! I can't access it, but from what I have read in the past, that's exactly the sort of thing I was thinking about.

Or perhaps more data from VetCompass: https://www.vetsurgeon.org/b/veterinary-news/posts/research-shows-surgery-is-the-better-option-for-canine-ccl-ruptures

[/quote]

How about cats? That study says nothing about cats with cruciate rupture. I have one of those now, and wondering wheter to treat it conservatively or surgical. My own cat was operated 20 years ago by an enthusiastic surgeon, but I always felt it was a lot of problems, and that the cat developed early onset arthritis due to the surgery.

RE: Should there be a minimum evidence base for surgery?

Neil Wheadon — Fri, 21 Jun 2024 17:09:30 GMT

[quote userid="2100" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244936#244936"]Hi Neil, to be fair, I wasn't talking about something which defines which patients are suitable or not, but just trying think of ways that owners could be helped to make a more evidence-based decision, especially in the current financial (and scientific) climate when there must surely be a greater need to justify the expense of increasingly expensive procedures.[/quote]

I respectively disagree.

I’m not sure exactly what surgical interventions you trying to compare? For in the world I live in there is usually only one way to remove an intestinal foreign body, surgically treat a pyometra etc it is only in orthopaedics that different techniques are done and to be honest all are a similar cost? The majority are treated in a similar way

So to compare you will need more tests/more costs to get a proper comparison.

Neil

RE: Should there be a minimum evidence base for surgery?

Arlo Guthrie — Fri, 21 Jun 2024 08:33:40 GMT

[quote userid="8958" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244934#244934"]To conclude, grading and feedback is a recipe for disaster in my opinion, we're under enough pressure and a lack of vets wanting to 'remove a mass' or 'spay a fatter bitch' as it is.[/quote]

Hi Neil, to be fair, I wasn't talking about something which defines which patients are suitable or not, but just trying think of ways that owners could be helped to make a more evidence-based decision, especially in the current financial (and scientific) climate when there must surely be a greater need to justify the expense of increasingly expensive procedures.

[quote userid="4181" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244935#244935"]Canine Cruciate Registry, for instance https://ccr.rcvsknowledge.org/ ?[/quote]

Ha. There you go! I'd forgotten about that one! I can't access it, but from what I have read in the past, that's exactly the sort of thing I was thinking about.

Or perhaps more data from VetCompass: https://www.vetsurgeon.org/b/veterinary-news/posts/research-shows-surgery-is-the-better-option-for-canine-ccl-ruptures

RE: Should there be a minimum evidence base for surgery?

Rob Loxley — Fri, 21 Jun 2024 06:15:49 GMT

[quote userid="2100" url="~/f/clinical-questions/30981/should-there-be-a-minimum-evidence-base-for-surgery/244933#244933"]One thought jumped into my mind ... a website for owners to report the results of surgery at certain periods after the event. Quite simple. Enter animal. Select a procedure. That defines the reporting period. Then enter scores for various measures of success (for that surgery), perhaps three or four. But then you also need to get people to enter data when they did NOT proceed with surgery, which would be more difficult![/quote]

Canine Cruciate Registry, for instance https://ccr.rcvsknowledge.org/ ?

RE: Should there be a minimum evidence base for surgery?

Neil Wheadon — Thu, 20 Jun 2024 22:08:24 GMT

My mother has been waiting 16 months for a hip replacement on the NHS. Fits all the criteria, still working (she does market research, gets her out) is a widow and lives alone.

Has been referred to a specialist who have refused to complete because she isn't the perfect candidate. Her urea is mildly elevated but the killer was her haemaglobin was 1 point (119 verses 120) below normal. In other words the centre will only operate where there is a better chance of success.

To conclude, grading and feedback is a recipe for disaster in my opinion, we're under enough pressure and a lack of vets wanting to 'remove a mass' or 'spay a fatter bitch' as it is.

She's now back in the NHS system and her haemaglobin has returned to normal, do I blame grading? Yes it has a part to play in this fiasco, don't extend it to our profession

Neil

RE: Should there be a minimum evidence base for surgery?

Arlo Guthrie — Thu, 20 Jun 2024 07:16:15 GMT

Gosh, Beats, wow, that's telling me! And yes, clearly a dumb idea, although I would stress that I wasn't suggesting all surgery should be licensed!

It's just that the lack of evidence must in some cases make it very hard for the owner (or the surgeon for that matter) to assess the real risk, and therefore the merits of the surgery.

And as David Mills said, the recommending surgeon may be biased.

And if the animal is insured, then it is more likely, I would have thought, for surgery to proceed regardless, which is an inflationary pressure on insurance fees.

I wonder if there is any other way to help owners make a more informed assessment of the risks / rewards.

One thought jumped into my mind ... a website for owners to report the results of surgery at certain periods after the event. Quite simple. Enter animal. Select a procedure. That defines the reporting period. Then enter scores for various measures of success (for that surgery), perhaps three or four. But then you also need to get people to enter data when they did NOT proceed with surgery, which would be more difficult!

Or maybe try and gather some basic evidence (survey owners and or vets about the results of surgery, or consequence of not proceeding) - may be anecdotal, but at least a start.

RE: Should there be a minimum evidence base for surgery?

Beats — Wed, 19 Jun 2024 11:29:11 GMT

The entire of surgery has a very limited evidence base and will always be thus.

Not much better in humans, but will always be extremely limited for vets.

Number of reasons for this, e.g.:

- the deductions from a study are that that surgeon, doing that procedure on those patients gave those outcomes: this may tell us more about the surgeon than the procedure. e.g. Look at this study: The outcome of combined urethropexy and colposuspension for management of bitches with urinary incontinence associated with urethral sphincter mechanism incompetence - PubMed (nih.gov) If that was a drug, then an average vet may consider prescribing it. it is not a drug, it is a surgical procedure and I am not going to perform it as well as Dick White - I can't just prescribe it. The positive results tell us more about what happens when Dick White, or someone he has directly mentored, perform the procedure than what would happen if others do.

- there is limited funding or interest in performing clinical studies, meaning small case numbers with difficulty extrapolating to a given case in front of you.

- we don't want a scascade (surgical cascade - the logical follow-on from the over-regulation of medicines that we have) where if money is spent showing a surgical procedure to be safe and effective it is then licensed and all vets must perform this surgical procedure by preference as has been proven to be safe and licensed. We must now all do the theresa welsh fossum double ligation on the ovarian pedicles to spay a bitch say. I think loose regulation and allowing conflicting opinions is much healthier.

- all the usual problems with evidence-based medicine (surgery): positive publication biases, academic-biases, commercial biases, questionable scientific reasoning, low case numbers, relevance to individual cases, out of date etc.

For surgery, using reasoned logic, critical thinking and, most crucially extensive experience (either personal or shared) of similar cases, with what evidence is available or attainable, is all that can be hoped for. Andy has articulated the reasoned logic for fixing this fracture, and in his hands this may be the most appropriate option to consider (cost-aside). In my hands, an approach as per David Mills and Stigen would be most appropriate. Do I see cases where they have a pedal lameness that may be the result of abnormal weight-bearing on a pad after a malunion or other deformity - yes. Do I think I could fix it in a manner that would reduce this risk without elevating other risks - no. Would I do anything other than keep the cat restricted for a bit - no. Do I think Andy could do a tidy job in repairing it with a different balance of risks - yes (although I'm not totally sure on what this would look like in terms of actual surgery to be done!)

Human orthopedic literature is fun. Here's one of my favourite examples on the topic of whether anatomic reduction of a fracture makes a difference (quite old now):

Articular fractures: does an anatomic reduction really change the result? - PubMed (nih.gov)

Within that extensive review you will find reference to a study from the 1980s where universally poor outcomes were obtained in one type of fracture if the joint parts were not accurately lined up again. This is cited as fact in the review and then proagates further from that. If you bother to look up the cited study (not online of course) then you discover that a "poor outcome" was defined as not doing well clinically OR the bones at joint not being accurately lined up on an x-ray - so a poor outcome in case of not lining them up was an inevitable outcome by definition and thus meaningless!

If we look at distal adial/ulna fractures you can read in vet textbook that 80% do not heal without surgery in small breed dogs. If you follow the citation (which I did after witnessing 6 in a row heal without surgery and thinking that seems to be beating the odds) then yo ulearn that the referenced study did indeed show a poor overall outcome, but was actually looking at pinning and external coaptation of radii and the data can be neatly put another way whereby all those over a year didn't heal and all those under a year did heal... If faced with a 6 month old yorkie that might be relevant information to have included...

Many surgical procedures are, in essence, experimental. That they are not part of actual experiments with carefully studied outcomes is unfortunate, but I think inevitable. I think would be worse the other way around. Have a look at some of the publications on elbow dysplasia. Here is one that claims arthroscopic surgery is helpful - here is another that claims it does nothing - neither study is going to convince anyone of anything, but doesn't mean aren't worth publishing, just have to be realistic at what will be achieved and continued to use reasoning and allow different expressions of opinion and not uniformity within profession:

Conservative versus arthroscopic management for medial coronoid process disease in dogs: a prospective gait evaluation - PubMed (nih.gov)

"AT dogs had increased mechanical asymmetry at 4 and 8 weeks compared to the CM group revealing surgery worsened limb function. There was no significant difference in mechanical symmetry between groups at 26 and 52 weeks."

Comparison of three methods for the management of fragmented medial coronoid process in the dog. A systematic review and meta-analysis - PubMed (nih.gov)

"The results were that arthroscopy was superior to medial arthrotomy and medical management"

In the absence of evidence, different vets will draw different conclusions, some of us are more inclined to say "what's the point" if we are unconvinced by the rationale behind a surgery, and our experience doesn't match up. I haven't ever done elbow arthroscopy, and would not be inclined to start based on lack of convincing evidence of benefit, but others will be at the forefront of experimental treatments to try to assist, and we need vets doing this sort of thing, otherwise we never find beneficial treatments. That said, another decade has passed and I'm no more convinced and see that I'm not alone:

Therapeutic success in fragmented coronoid process disease and other canine medial elbow compartment pathology: a systematic review with meta-analyses - PMC (nih.gov)

"Given the results presented and the limited availability of high-quality studies, the authors believe it is plausible that for many affected dogs, conservative therapy could be on par with surgery. And as long as there is absence of strong evidence supporting the superiority of surgical treatment, conservative therapy might more often be the sensible approach for both ethical and financial reasons."

Someone that does more of a surgery is more likely to recommend that surgery by definition: they will be better at it as they do more of it and likely get better results with it as a result. I think in the inevitable absence of evidence that individual vet recommendations will continue to vary wildly and that that is completely appropriate and the way it should be. Ask 2 vets and get 3 opinions and all that. If you aim for too much uniformity then you risk losing the variety of opinion that allows innovation - just look at how use of medicines has gone down the plug hole as cascade has crept in further and further to everyday practice.

EDIT - and good luck getting any proper science done in clinical practice in UK - you need a home office license I think if you apply basic scientific principles like randomization, so the environment is kind of against hobbyist rigorous science in vet general practice.