A Venomous Snakebite Case in Australia Supports the Efficacy of Sutherland’S Original 1979 Pressure Immobilisation First Aid
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http://members.iinet.net.au/~bush/Bush%202018%20Snakebite%20ASP110218.pdf A venomous snakebite case in Australia supports the efficacy of Sutherland’s original 1979 pressure immobilisation first aid. Brian Bush, Manager, Snakes Harmful & Harmless, 9 Birch Place, Stoneville, Western Australia 6081 Address all correspondence to – [email protected] Abstract The venoms of Australian snakes rarely cause necrosis, but on three occasions the author has experienced bite site tissue injury since employing pressure immobilisation first aid where a bandage is applied directly over bite site as per Sutherland et al. (1979): once by Tiger Snake ( Notechis scutatus ) and twice by Common Mulga Snake ( Pseudechis australis ). This may demonstrate the efficacy of that first aid treatment in sequestering the concentrated venom to the bite site. It is suggested that the local tissue damage is a result of the quantity of venom injected and not related to the time the bandage is in place. Included also is a firsthand account of a bite from P. australis that occurred in a remote location without medical assistance and a photographic record of the envenomed finger showing progressive destruction of tissue and partial natural resolution. __________________________________________________________________________________ Introduction Australian Health Department suggested the bandage be bound over the bite and then Australia has a large number of venomous extended to the extremity before proceeding to snake species, with about 134 of these being bind up the limb. In 2001 Sutherland et al. , front-fanged marine and terrestrial when using a single bandage to achieve both Austropapuan elapids. About 3,000 bites are pressure to the bite site and immobilisation of reported annually with as many as 500 of these the limb , suggested commencing bandaging at requiring hospitalisation and an average of two the extremity, extending it up the limb over the being fatal (Johnston et al. 2017, Welton et al. bite and as high as possible. In 2005, the 2017, White 1998). Australian Resuscitation Council reverted to the original 1979 first aid and stated that a First aid treatment for snakebite to simple pressure bandage over bitten area leads limbs in Australia since late 1979, has involved to at least partial occlusion of capillaries and the use of a pressure bandage firmly applied to lymphatics. It also provides the alternative, the bite site and extended as high as possible, when the bite is not on a limb, to apply firm before extending the bandage back down the direct pressure on bite site. In 2014, St John limb to the extremity, then immobilising the Ambulance combined the 2001 technique with limb with a splint or similar and known as the original 1997 PI first aid, suggesting the pressure immobilisation (PI) first aid (Figure use of two bandages with the first being 1). Developed by Sutherland et al. (1979), this applied directly over the bite and then a treatment has since been variously modified second, commencing at the fingers or toes, with minor changes that can only contribute to covering the whole limb. In 2017, the the confusion a layperson may experience Department of Pharmacology and when called upon to perform emergency Therapeutics, The University of Melbourne snakebite first aid. In 1997 the Western made recommendations (discussed below), © Bush, B. 2018. Snakes Harmful & Harmless ASP110218: 12pp. http://members.iinet.net.au/~bush/Bush%202018%20Snakebite%20ASP110218.pdf that, whilst accurate, risk complicating digit, or local scarring is a small price to pay emergency snakebite first aid. Their by the victim, if their death is the alternative as recommendations appear impossible to achieve a consequence of premature removal of the in an emergency situation unless the victim or bandage. bystander has on their person a cloth pad and a guage capable of reading bandage pressure; In the case history reported here, the and there is little alternative improvisation first bandage was removed from the bitten area aid provided. (finger and hand) seventy-five minutes after envenomation, although the degree of necrosis Rarely is local tissue damage seen as a in this record is the most severe of the three major result of Australian snakebite. It is bites where the author experienced local tissue fortunate that this is the case because in many damage. In all of these, the snakes involved other countries some snakes possess powerful hung on and had to be grasped by the head to tissue-destroying venoms that are severely be removed, suggesting a maximum amount of debilitating to victims and in many cases have venom injected. caused such significant damage to a limb that required its amputation. Although bite site tissue destruction is not often observed in Author's background – Australia, it has been reported by White (1987) I describe myself as a field herpetologist that after bites from Tiger Snake ( N. scutatus ), for over sixty years has been involved with Taipan ( Oxyuranus scutellatus ) and Common reptiles. This was initially as a hobby in the Mulga Snake ( P. australis ). Razavi et al. early days, but since 1976 I have collected (2014) when looking specifically at P. reptile specimens for the Western Australian australis bites, found about ten percent (2 of Museum (WAM) and other institutions; and 21) of envenomed subjects developed local since 1987 I have run a reptile education and tissue injury around the bite site that required venomous snake consultancy business, which further treatment. Snake exhibitor, Neville primarily involves providing occupational Burns required the surgical removal of a finger health and safety training to manage snakes in after a bite from a Red-bellied Black Snake ( P. remote workplaces, especially for the resource porphyriacus ) (N. Burns pers. comm.); and industry in Western Australia (WA). during this study, the author had it reported to him that in March 2017 a victim’s toe required As a part of this job, I spend about amputation after a bite near Lismore, New two-thirds of each year alone driving between South Wales from a Rough-scaled Snake mine sites and camping in the bush to avoid (Tropidechis carinatus ) (T. Tasoulis pers. the soft life of the company camps, but more comm.). In all of these cases PI first aid was importantly to allow me to find, examine and applied. photograph wild reptiles under various licences issued by the WA wildlife authority, currently It has been suggested that local tissue damage the Department of Biodiversity, Conservation after snakebite may be a result of leaving the and Attractions. pressure bandage in place for a considerable period (Harvey et al. 1982, Sutherland et al. This regular and consistent handling of 1981a), however, if this is the case, there is no snakes has exposed me to several serious bites, available solution because the time the especially by the large medically significant bandage is in place is determined by several species, with a total of seven envenomations variable, but uncontrollable factors, especially where I had medical intervention at various in Australia because of the vast distances metropolitan and regional hospitals (Table 1). impacting on the time it takes to recover a There were also numerous other bites where victim when isolated in the bush; and the circumstances at the time precluded me particularly so when the general from seeking medical assistance and I just had recommendation is that the bandage be left in to “weather the storm”, relying only on the place until medical treatment is sourced and tourniquet treatment in the early days and on then the doctor is the one deciding when to PI first aid since the early 1980’s to pull me remove it. Although the first aid treatment through. should not put the patient at risk, the loss of a 2 © Bush, B. 2018. Snakes Harmful & Harmless ASP110218: 12pp. http://members.iinet.net.au/~bush/Bush%202018%20Snakebite%20ASP110218.pdf Because of my history, snakebite holds individuals will bite savagely, hanging on and no mystery to me, but I appreciate the chewing. Patients receiving its bite may psychological trauma the average citizen may require Black Snake antivenom during experience after a bite, especially because of treatment and this is probably the case also their possible exposure to the exaggerated after bites from closely related Spotted Mulga negative misinformation often presented by the Snake ( P. butleri ) and Weigel’s Mulga Snake media and others regarding Australian snake (P. weigeli ). However, this would be venom toxicities obtained initially during specifically identified when diagnosis is made laboratory studies on mice by Broad et al. using the venom detection kit (VDK). Tiger (1979). I believe this has resulted in the Snake antivenom is considered an effective experiences of many snakebite victims neutralising agent for several eastern reported by the media being overly emotive Australian members of this group, namely accounts reflecting the heightened trauma each Collett’s Snake ( P. colletti ), Blue-bellied Black survivor was exposed to at the time. Snake ( P. guttatus ) and Red-bellied Black Snake ( P. porphyriacus ) (White 1995). Although mulga snakebite has the potential to cause death, this is exceedingly The Common Mulga Snake can yield rare, with the last confirmation I can find exceedingly large volumes of venom; with attributed to this species being in 1969 when previous 'milkings' I have undertaken Tiger Snake antivenom was used instead of commonly exceeding 350mg dried weight. The Black Snake (Jelinek et al. 2004, Sutherland et maximum yield produced by a large individual al. 2001). Snake exhibitor, Fred Duffy’s death was 1500mg recently reported by the in 1977 is listed as the result of mulga snake Australian Reptile Park in New South Wales bite by Mirtschin (2006), but a question mark (Australian Reptile Park 2016). has been included in this record regarding the authenticity of the identification of the species Its venom consists primarily of involved.