Diagnosis & Treatment — First aid / lay people
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.
How can absorption and circulation of the venom be delayed?
Elapids: Cobras, except for Naja nigricollis, Naja nubiae, Naja pallida, Naja katiensis, Naja oxiana (?) and Walterinnesia sp. (?):
- Compression-immobilisation method or comparable methods and splinting of the bitten extremity.
- Avoid pressure points when applying the splint (padding). Transport the patient.
Viperids/elapids (N. nigricollis, N. nubiae, N. pallida, N. katiensis and Walterinnesia sp.) and crotalids:
- 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.
The risks of the compression-immobilisation method limit its use to elapid bites that cause signs of paralysis. This excludes N. nigricollis, N. nubiae, N. pallida, N. katiensis and Walterinnesia sp. (?), which, according to current knowledge, do not cause signs of paralysis but rather local symptoms of envenoming, at times marked. In contrast, local swelling following Cobra bites that cause neurological signs and symptoms (N. haje and possibly N.arabica, N. melanleuca and N. senegalensis) is minor or not present at all.
With all elapid bites that cause signs of paralysis, efficient delay of transport of the venom into the systemic circulation may be the decisive life-saving measure, as the neurotoxic effects of the venom begin rapidly, and there is a risk of respiratory failure occurring before medical facilities can be reached.
Exposure of the eyes or mucous membranes to venom
Spitting cobras: N. nigricollis, N. nubiae, N. pallida, N. katiensis.
Eye irrigation/thorough washing of the mucous membranes with water.
Average time between the bite and death
- Cobras (N. haje): minutes to hours (average 8 h).
- Bitis arietans: 10–30 h (Visser and Chapman 1978).
- Echis sp.: 25 h–41 days (median 5 days) (Warrell 1990b).
This information makes it possible to assess the probability of reaching medical facilities in time and, barring other circumstances, justifies the use of a tourniquet for elapid bites (see above).