Diagnosis & Treatment — First aid / lay people
General observations
This Diagnosis & Treatment section is based on analysis of envenoming caused by V. aspis and V. berus and to a small extent by V. ammodytes (see the Biomedical database entry for Vipera sp. (European vipers)). Documented cases of envenoming due to V. latasti, V. kaznakovi, V. lebetina, V. seonaei and V. ursini are rare or simply not available. See also Diagnosis & Treatment: Terrestrial snakes: North Africa, Near and Middle East and the Biomedical database entry. The signs and symptoms of envenoming caused by V. ammodytes, V. aspis, V. berus, V. latasti and V. ursini are described as being similar with the exception of V.berus, V.ammodytes and in particular V.aspis in which neurotoxic effects are observed in certain geograpgical areas (Warrell 2010). Envenoming due to colubrids and the pitviper Gloydius halys in Europe is similarly poorly documented or not at all.
General problems
- Fear,
- collapse, loss of consciousness.
- Calm the patient.
- Place the patient in a stable lateral position, or possibly the Trendelenburg position (shock position).
Anxiety (fear of death) plays an important role following accidents with venomous animals and has an additional negative influence on the clinical course after an accident.
Loss of consciousness after an accident with a venomous animal can have many causes. It is important to place the patient in a stable lateral position to avoid aspiration. If peripheral circulatory failure is present, the shock position may improve the patient's condition. If resuscitation is necessary, it is only in exceptional cases that lay people will be sufficiently well trained to be able to intervene.
Early anaphylactoid signs and symptoms
Nausea, vomiting, abdominal colic, diarrhoea, incondinence of urine and faeces, sweating, hives, swelling of the face, lips, gums, tnogue, throat, breathing difficulties, collapse, loss of consciousness (within five minutes to hours after the bite).
Early anaphylactoid signs and symptoms can be treated with an oral or parenteral H1 blocker or adrenaline (epinephrine) (Epi-Pen), depending on severity (Warrell 2005).
How can absorption and circulation of the venom be delayed?
- Immobilisation of the bitten extremity using a splint (piece of wood or something similar).
- Avoid pressure points when applying the splint (padding).
- Transport the patient.
With European viper bites, all forms of tourniquets and compression bandages are problematic and may even be dangerous. The marked local effects of the venom lead rapidly to swelling of the bitten extremity, such that arterial occlusion pressures may be reached or exceeded, with consequent ischaemic damage distal to the tourniquet. Furthermore, the local effects of the venom are intensified by confinement of the venom to a small volume of tissue.
Average time between the bite and death
34 h (mean) (6–60 h) (Warrell 1987).
However, death may also occur within minutes after the bite due to autopharmacological effects of the venom.