Issue 47 / 7 December 2015

I WAS talking to an emergency medicine colleague recently about whether antivenoms should be used in rural Australian hospitals and medical centres, or if it was better to transfer the patient by road or air to a regional or metropolitan hospital.
 
He said that since most small rural health facilities don’t have pathology services or intensive care wards where patients can be closely monitored and, if necessary, maintained on life support, wasn’t it better to move the patient to a larger centre that had all the bells and whistles? And, if that is the case, then surely there is no need to keep supplies of antivenom in rural areas? 
 
His argument seems sound, and is certainly supported by a “Clinical focus” article published in the MJA, which said snakebite patients in Australia must all be treated in hospitals with onsite laboratories, antivenom and doctors who can treat anaphylaxis.
 
My friend makes another good point — snakebite is rare, and not all cases involve envenomation. So, most rural health professionals don’t have the experience needed to manage snakebites well.
 
But are these arguments really in the best interests of the patient? 
 
Snakebite is a time-critical medical emergency and the earliest possible commencement of antivenom immunotherapy can be critically important when clinically significant envenomation is present. Surely delaying administration while a patient is transferred to another hospital must be counter-productive, especially if it places them at risk of haemorrhage or severe paralysis?
 
It can also be costly. With rotary-wing retrievals costing more than $5000/engine hour plus crewing costs, and fixed-wing retrievals costing $2400/engine hour plus crewing costs and land transport costs, transferring every snakebite patient to a major hospital for assessment and treatment comes at a price. 
 
Shouldn’t we look outside our own experience to gain other perspectives on the management of rural snakebite?
 
Having managed a large ongoing study of snakebite in Papua New Guinea (PNG) for the past 15 years, I have first-hand experience of the challenges across the whole spectrum of health care facilities there. And some of them are enormous.
 
Crumbling infrastructure, ancient or broken equipment, dysfunctional drug supply lines, demoralised and desensitised health workers and a bureaucratic system with myriad flaws all present pitfalls and barriers to effective service delivery, and particularly so for the most critically ill and unstable patients. Snakebite is a key case in point.
 
Our neighbour has species of brown and black snakes, taipans and death adders, and uses Australian antivenoms, although shortages are commonplace. 
 
Remarkably though, when antivenom is available at a rural health centre in PNG, it is routinely administered by non-doctor health professionals — typically nursing officers or health extension officers who rely on a simple bedside test to detect coagulopathy, basic protocols and fundamental hands-on clinical skills.
 
Patients with suspected snakebite who have abnormal bleeding, or a positive 20-minute whole blood clotting test (20WBCT) result and/or any signs of cranial nerve palsy or other paralysis are treated with a single vial of antivenom as soon as possible. If necessary, patients are then moved to a referral hospital by whatever means available. 
 
My own observations are that early antivenom administration in rural health centres in PNG helps envenomed patients more than it harms, and ultimately saves lives.
 
Some will criticise the use of a simple bedside test using glass tubes and a wristwatch, but base their criticism on examples where no standard protocol is in place and the test was not first validated with blood from healthy volunteers, leading to common errors. In PNG, the test has been validated for the local population and uses a standard protocol with easily obtained sterilised soda-lime penicillin vials. This simple low-tech test reliably and accurately predicts abnormal haemostasis.
 
But there is more to treating snakebite than performing a simple test. In PNG, a national training course in snakebite management is heavily focused on teaching practical clinical skills including history-taking, patient examination and diagnosis, airway management, antivenom administration and the treatment of antivenom reactions. Rural health workers can now quickly evaluate cases of suspected snakebite and make informed decisions about whether antivenom is indicated or not, and know how to manage reactions. 
 
An excellent Australian course, run through the University of Adelaide by Associate Professor Julian White, is currently struggling to enrol sufficient participants. This is unfortunate and disappointing, because rural health professionals could learn a great deal from this course that would benefit victims of envenoming in rural Australia.
 
Isn’t it better to train and educate our rural health workforce to improve their competencies, rather than pull services and skill sets away from the bush?
 
My colleague, having now seen how snakebite is managed in PNG, still says that even though some states, such as Queensland, have policies for antivenom administration by remote area nurse practitioners or paramedics, the concept that snakebite can be successfully treated outside a large hospital, let alone by a non-doctor health professional, will be rejected by many of his peers. 
 
At least he agrees that as snakebite is time critical and lives can be at stake, perhaps Australia can learn some lessons from our PNG neighbours.
 
 
Dr David Williams heads both the Australian Venom Research Unit at the University of Melbourne, Parkville, and the Charles Campbell Toxinology Centre at the University of Papua New Guinea, Port Moresby. He is currently coordinating a Phase II antivenom trial at Port Moresby General Hospital and is a passionate advocate for the need to improve snakebite treatment in the developing world.
 

10 thoughts on “David Williams: Snakebite lessons

  1. John Raftos says:

    Early antivenom use is safe and in the patient’s best interest.

    Transfer to a toxicology centre is just a way for the toxicologists, many of whom have never seen a snakebite, to establish their empire and justify their existence.

    I have seen antivenom use delayed several times recently because the toxicologist wanted to base its use on blood tests, rather than the clinical picture.

     

  2. JHeywood says:

    Snakebite treatment in rural Australia: Patient was given antivenom after multiple bites by a brown snake. A second dose was given but patient then required adrenalin.  I support further tests – simple tests as used in PNG?  – before giving a second dose. The patient recovered, but later developed MND and has since died.

    I think we could learn from PNG’s experience.

    PS. This a is very user-unfriendly place to type in words as you have to hit the keys very hard.

     

     

  3. Horst Herb says:

    When I started working in Australia, I soon had to deal with a brown snake bite of a 3yo child. The first dose of antivenom allowed us to break thorugh the cardio-respiratory arrest that had already ensued despite best resuscitation efforts, but only for 15 minutes. The second dose gave another short lasted reprieve – phone advice from specialist at the big smoke was that we may need many more doses. However, 2 was all we had, and another dose could be sourced by ambulance from a neighbouring town within 45 minutes of ongoing CPR.
    The chopper that was requested  immediately after making the diagnosis arrived… more than 5 hours later, too late. The child died. Maybe we would have had a chance if we had had more antivenom, but we certainly would not have stood any chance whatsoever by waiting for the chopper which could not fly because of “bad weather” (a bit of wind and rain).

    My experience in my current working location in Dorrigo, northern NSW, is that retrieval as a rule takes 4 hours minimum counting from the time it is requested. We are rural, but not remote – remote areas possibly fare much worse. Anybody suggesting air retrieval is a generally viable option just has no idea of the realities of this vast and mostly poorly developed country and should be forecfully dragged out of their sheltered urban ivory tower in order to get a whiff of the real world first before they are allowed to give any “best management advice” for rural and remote circumstances.

    With regards to the course struggling to find attendants – the rural practitioners who would be the most likely target audience rarely can take a whole week off. Locums are prohibitively expensive and even for a fortune most difficult to source. 

  4. Bryan Walpole says:

    I have given A/V for tiger snake twice in remote areas, having been flown in by Helo. In both cases, there had been over 12 hours delay, both cases were uneventful, followed by rapid recovery of symptoms, and later discharge home, from ED obs. Two cases means nothing, but in 100s of cases treated through ED, I have never had to use adrenaline, despite the warnings and protocols from Sutherland and AVRU

  5. University of Newcastle says:

    As snakebite in Australia is rare, individual clinicians are unlikely to accrue significant clinical experience. Many patients present to relatively isolated centres and it is not clear whether they are envenomed. In such situations providing clinical support to clinicians is essential. The four Australian poisons centres (PIC) do this on a 24/7 basis with a national roster of clinical toxicologists who have direct bedside experience in treatment of envenoming and poisoning, and whose advice undergoes continuous peer review. Last year the four PICs took over 700 snakebite calls from hospitals outside major centres.

    The PICs facilitate research on snakebite via the Australian Snakebite Project, resulting in 22 research papers and led to major revisions of State treatment guidelines. This culminated in a 2013 Clinical Focus review published in the MJA. These guidelines already recommend giving antivenom before transfer in patients who are clearly envenomed (Box 3 flowchart). Thus in Australia it makes sense to transfer patients (sometimes after antivenom) if they need to have laboratory tests for potentially serious snakebite.

    We conduct collaborative research in Sri Lankan hospitals where experienced clinicians treat up to 2000 snakebites per year. However in that resource poor setting published experience with the whole blood clotting test is that it delays antivenom use (due to frequent false-negatives).

    An issue for clinicians in Australia is how to invest their educational time. Snakebite is rare with low mortality. Courses run by Toxicology And Poisons Network Australasia provide teaching by expert toxicologists on envenoming and poisoning.

    Not all lessons from overseas are easily extrapolated to Australia or vice versa.

  6. Barbara Bradbury says:

    Has any thought been given to an online audiovisual course and transferring the Adelaide course to that?

    Most of the above has been written from a medical point of view. It seems that the arguments are influenced by American texts and the notion that every town has full medical facilities within a short distance. What has happened to the pioneering spirit of colonial times? Getting to an ED centre in the first place may still be difficult for many Australians. The numbers game of rarity to justify not learning is clearly playing a role.

    The original post was sane and sensible. Much of the rest was too impractical for the Drover’s Wife living alone for long periods, or the retired who prefer home on the land to a nursing home – easy for whom?

    So has anyone thought of intelligent people who want to learn being taught online? Who has looked into the history of successful snakebite treatment since 1770? And from Aboriginal medicine?

  7. Andrew Dawon says:

    Providing online distance education is very useful as it allows access both for people who are geographically remote or who need to fit education around their work and personel schedules. It also places them in contact with interested peers as well as the tutors who teach the course

    Distance education in clinical toxicology (including toxinology/snakebite) with asynchronus interaction (ie discussion boards) formal assessment and feedback has been delivered in Australia since 2004, similar courses have been developed and delivered from Sri Lanka since 2010. Face to face teaching is also extremely valuable and provides real time interaction but is harder to access

    The first aid and hospital  treatment of most snake bite is a relatively simple application of widely distributed guidelines or brief educational sessions and can be initiated in settings with low resources. However,  probably no course or guideline can cover all the rarer variations that can occur with an individual case so calling someone expertise and experience is very useful.

  8. Alex Harris says:

    Just looked at that Adelaide course – 6 days covering every venomous animal in the world – no wonder it is struggling to enrol enough people. Surely a 1 day course is enough to teach appropriate snake bite management?

  9. Sue Ieraci says:

    Alex Harris may be right. While those who work in a sub-specialist area naturally see their area as the most important in the clinical spectrum, but a six-day course on envenomation might not be what rural clinicians are looking for. Clinical priorities in PNG are VERY different to Australia – even remote Aus. Tip: design the course to suit needs, rather than vice versa. 

  10. Dianne Knoll says:

    The high cost of antivenom means that small rural health services cannot afford to stock it.

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