Latest on Adder bite treatment?

Re: Latest on Adder bite treatment?

Hannah Wynne Richards — Fri, 24 Apr 2015 09:25:39 GMT

Would doctors be so reluctant to use anti-venom in the case of a crawling baby bitten on the face. That is the nearest human comparison I can make to 50% of the cases we are presented with.

Wynne

Re: Latest on Adder bite treatment?

Bob Russell — Fri, 24 Apr 2015 09:21:05 GMT

If you consider the relative size of our patients then the amount of venom per case is likely to be similar to a small child being bitten. Humans are also quite unlikely to be bitten on or around the face (unless a pretty odd human!).

The comparison between the misery of a dog treated with antivenom and not treated can be quite dramatic even if the final outcome is similar.

Unless VPIS have altered their recommendations in the last couple of years, our approach is broadly similar to theirs (of course really it is based on their advice!).

Owners must be made aware of the risks but nobody has refused permission. We are only treating the most miserable patients!

Re: Latest on Adder bite treatment?

Thomas Johnson — Fri, 24 Apr 2015 09:01:07 GMT

I was talking to a doctor about the anti-venom a couple of nights ago, apparently in humans the risk of anaphylaxis is 50%, and they do everything they can to avoid having to give it. I wonder if this is where the worry comes from for us, but the risk in dogs must be much lower as no one here has mentioned seeing a dog have an anaphylactic reaction to the anti-venom.

Re: Latest on Adder bite treatment?

louise nixon — Thu, 23 Apr 2015 10:25:08 GMT

[quote user="Will McMullan"]

Where do you source your anti-venom?

[/quote]

We keep quite a bit in stock. Get in through Centaur.

Re: Latest on Adder bite treatment?

Anthony Dennison — Thu, 23 Apr 2015 10:08:21 GMT

[quote user="Jo Dyer"]Personally I suppose I was a bit concerned about the sedating effect of the opiate masking any respiratory or cns depression due to the venom, but that's probably just me overthinking it[/quote]

I went to a CPD evening by North West Surgeons this week about Trauma; a section by the anaesthetist said that she doesn't worry about respiratory depression in painful animals and wouldn't withold opiates. If there was any concern, titrating up is good.

Re: Latest on Adder bite treatment?

Hannah Wynne Richards — Thu, 23 Apr 2015 09:37:31 GMT

Fair enough.

Wynne

Re: Latest on Adder bite treatment?

Jo Dyer — Thu, 23 Apr 2015 09:28:54 GMT

[quote user="Hannah Wynne Richards"] Just 1 point. Why not dex and opiate. I'd worry about giving an NSAID in case I did get an anaphylactic reaction and would have to give steroid.[/quote]

I'm sure that's fine, and buprenorphine was sometimes given with the dex. Personally I suppose I was a bit concerned about the sedating effect of the opiate masking any respiratory or cns depression due to the venom, but that's probably just me overthinking it. We never saw an anaphylactic reaction but maybe they happen, I guess you could use antihistamine instead of dex if so.

Re: Latest on Adder bite treatment?

Bob Russell — Thu, 23 Apr 2015 09:26:29 GMT

We use antivenom for head and face strikes unless they are bright and alert (which they rarely are!). Always antibiotics because tissue trauma and infection are pretty inevitable. I will give antihistamines (even suggest owners carry Piriton when walking in the Forest (may be more psychological benefit than real!).

I tend to use dexadreson at a fairly early stage plus opiates for pain.

Rarely hospitalise and i/v fluids tend to be more to dilute the antivenom than for the actual fluids!

Never had an anaphylactic reaction to slow i/v antivenom and have seen cases regularly over many years. The vast, vast majority do well!

The difference in the dogs demeanour following antivenom can be dramatic!

Re: Latest on Adder bite treatment?

Hannah Wynne Richards — Thu, 23 Apr 2015 08:56:16 GMT

Just 1 point. Why not dex and opiate. I'd worry about giving an NSAID in case I did get an anaphylactic reaction and would have to give steroid.

Wynne

Re: Latest on Adder bite treatment?

Jo Dyer — Thu, 23 Apr 2015 08:36:43 GMT

Where I used to work we saw at least 15 adder bites per year. I did an audit on the last 30 we saw, put it somewhere safe and now can't put my finger on it. However, from memory, 50% bites were on the head and 50% on a distal limb, none anywhere else, i.e. they stood on the snake or stuck their nose in it. We always gave antivenom over an hour or so, diluted in whatever volume of intravenous fluid was appropriate for the bodyweight and degree of shock. We also gave antibiotics, usually clav/amoxy 5 day course, and dex or meloxicam. I personally preferred nsaid but some of my colleagues preferred dex. We never saw an anaphylactic reaction which I think is always the quoted worry with antivenom. We sent them home after the antivenom/fluids and saw them 24 hours later, at which point they were all well on the road to recovery.

We saw a Westie once that had been treated at another practice without antivenom and presented to us several days later in early multiple organ failure with a skin slough. We gave it antivenom even at that late stage, and fluids etc for many days and eventually it recovered. We also heard anecdotes from clients about dogs treated at local practices without antivenom which had to be hospitalised for days and had a really rough time, most lived and the occasional one died.

So.....my advice based on my anecdotal evidence is that I would always give antivenom to reduce morbidity and mortality, no matter how large or small the swelling or how minor the early clinical signs, and I would always give nsaid for the analgesia.

Re: Latest on Adder bite treatment?

Hannah Wynne Richards — Thu, 23 Apr 2015 08:05:48 GMT

Vets Now will be left with a choice between preventing massive swelling and tissue necrosis, and stomach ulcers! Why didn't you use Comfortan?

Wynne

Re: Latest on Adder bite treatment?

Neil Wheadon — Thu, 23 Apr 2015 00:00:34 GMT

[quote user="Andrew Kent"]

[quote user="Will McMullan"]Where do you source your anti-venom?[/quote]

I guess if you see a lot you might keep it, otherwise it should be available through Vets Now Tox Box, see this link

Andy

[/quote]

I think this may be being phased out due to inactivity/costs

Bristol stopped a year ago, would be worth checking your local vets now to see if they have supplies

Neil

Re: Latest on Adder bite treatment?

Catriona MacIntyre — Wed, 22 Apr 2015 21:29:16 GMT

The most recent advice I had (2 summers ago, via VetsNow Referrals and Glasgow Uni Pharmacist) is that the risk of anaphylaxis due to the antivenom was as high, if not higher that the risk from the bite.

If the dog is otherwise well, I do not give IV fluids, but I ALWAYS give a hefty dose of antibiotics, preferably something with good tissue penetration that will also deal with anaerobes. Snakes carry some nasty bugs in their mouths.

I didn't have any cases that I thought were adder bites last year (although the owners were insistent), but the two definite cases I saw the summer before that I treated with 11mg/kg clindamycin bid, standard dose of meloxicam, and buprenorphine as both were in a lot of pain

Re: Latest on Adder bite treatment?

Christina Smith — Wed, 22 Apr 2015 20:07:16 GMT

IMO if presented early then glucocorticoids can make a huge difference to the level of local reaction. The problem is many cases are presented late or not even recognised until the local damage is severe. I think steroids make little difference in these cases. Once necrosis and skin sloughing is present I don't think antivenom makes any difference either. The last time I used it I sourced it from the local hospital, the dog had been bitten below the elbow 12 hours previously and the entire forelimb was oedematous and painful. Within 6 hours the limb was virtually normal. The late presentations or unrecognised cases are treated as I would any other bite wound. Apparently the earlier in the season the higher the dose of venom.

Re: Latest on Adder bite treatment?

Thomas Johnson — Wed, 22 Apr 2015 18:51:55 GMT

I've just seen a cat with an adder bite above its right eye, we close shortly so I've given it Metacam and Synulox, and it's gone to Vets Now, I'll see what else they've given it in the morning!

Re: Latest on Adder bite treatment?

Andrew Kent — Wed, 22 Apr 2015 18:38:43 GMT

[quote user="Will McMullan"]Where do you source your anti-venom?[/quote]

I guess if you see a lot you might keep it, otherwise it should be available through Vets Now Tox Box, see this link

Andy

Re: Latest on Adder bite treatment?

Will McMullan — Wed, 22 Apr 2015 17:53:12 GMT

Where do you source your anti-venom?

Re: Latest on Adder bite treatment?

louise nixon — Wed, 22 Apr 2015 17:48:38 GMT

I used to give steroids but have stopped now following the VPIS article. Now I use nsaids and antihistamines, admit for ivft and opioids if necessary. I use anti venom if the swelling extends above the next major joint, if swelling is excessive or prolonged or associated with petechiae. I think anti venom is recommended if the bite is on the face or muzzle; the guidelines I used reported that the anti venom can be given over 10-15 minutes diluted in saline. I did this for my last case as the bite was right on the tip of the nose, and the nostrils were swelling closed by the minute.

Re: Latest on Adder bite treatment?

Thomas Johnson — Wed, 22 Apr 2015 17:34:28 GMT

[quote user="Luca Poddighe"]

[quote user="Thomas Johnson"]I thought the data from VPIS showed that glucocorticoids were associated with worse outcomes for adder bites?[/quote]

I suppose it all depends if you are more worried of the poison or of the anaphylaxis. In all honesty I use glucocorticoids too

[/quote]

The VPIS recommends against use of glucocorticoids, the paper they published on follow up to adder bites reported to them is here:

http://veterinaryrecord.bmj.com/content/169/23/607.full?sid=d83f31b9-935e-465d-9201-180b9f7d0080#ref-12

And the paper they reference that suggests worse outcomes for patients given glucocorticoids is here:

http://www.ncbi.nlm.nih.gov/pubmed/15109890?dopt=Abstract

Re: Latest on Adder bite treatment?

Luca Poddighe — Wed, 22 Apr 2015 16:57:38 GMT

[quote user="Thomas Johnson"]I thought the data from VPIS showed that glucocorticoids were associated with worse outcomes for adder bites?[/quote]

I suppose it all depends if you are more worried of the poison or of the anaphylaxis. In all honesty I use glucocorticoids too

Re: Latest on Adder bite treatment?

Stephen Courtney — Wed, 22 Apr 2015 15:29:38 GMT

Do they really need antibiotics?

I never give antibiotics, and rarely give steroids unless there is evidence of vasculitis secondary to the bite. I prefer nsaids, antihistamines and would use antivenom only if I was worried about a severe reaction e.g. swelling about the throat area compromising airways - which I have never seen - or in the odd animal that seems extra poorly. Same for fluids - if they aren't shock, and are presenting several hours post bite which is the usual - then I don;t see the need.

Re: Latest on Adder bite treatment?

Thomas Johnson — Wed, 22 Apr 2015 14:31:56 GMT

[quote user="Christina Smith"]

Antivenom if available given iv in saline over 2-3 hrs. broad spectrum antibiotic cover and iv dexamethasone if required. Works well for me. If no antivenom then iv dexamethasone and broad spectrum antibiotic. I work on the basis that anaphylaxis is the main danger and that it's a contaminated puncture wound.

[/quote]

I thought the data from VPIS showed that glucocorticoids were associated with worse outcomes for adder bites?

Re: Latest on Adder bite treatment?

Simo — Wed, 22 Apr 2015 14:24:54 GMT

That's reassuring! Coming from a region blessed with no local venomous snakes at the Uni that was a chapter happily cut off from any course. So apart from the knowledge of the existance of an antivenom and the general notion that anaphilaxis is a problem with every animal toxin, I know little. Happy to know that my approach would not be much different from the locals and I don't need to panick as the patients are not likely to die for it.

Re: Latest on Adder bite treatment?

Hannah Wynne Richards — Wed, 22 Apr 2015 13:58:09 GMT

Fluids at twice maintainence so kidneys can get shot of venom, and opiates, as the bite will be painful. It's mainly Gm pos you need worry about, esp clostridia, so make sure you use penicillin

Wynne

Re: Latest on Adder bite treatment?

Mark Hedberg — Wed, 22 Apr 2015 13:40:30 GMT

Amusingly, with my first adderbite case in the UK I massively overreacted, hospitalizing, triaging, steroids, antihistamine, fluids...then one of our nurses pointed out that the UK 'poisonous' snake was about as toxic as a passive-aggressive love poem; annoying but rarely fatal.

(My previous job in Saudi, the local snakebite is most frequently the desert sidewinding horned viper - a rather unpleasant customer! Basically the skin goes necrotic and falls off the affected limb, very inconsiderate!)