Key investigations for snake bite
On arrival to hospital, perform the following key investigations in all patients with suspected snake bite:
- coagulation studies—international normalised ratio (INR)1, activated partial thromboplastin time (APTT), quantitative D-dimer1, fibrinogen concentration
- full blood count, including blood film to detect red blood cell fragmentation or spherocytes in thrombotic microangiopathy
- serum electrolyte, urea and creatinine concentrations
- serum lactate dehydrogenase concentration
- serum creatine kinase concentration
- urinary analysis—to detect myoglobinuria.
For patients administered antivenom, repeat the above investigations at 6 and 12 hours after giving antivenom, then every 24 hours until effects have resolved.
For patients not administered antivenom, repeat the following investigations 1 hour after releasing the pressure bandage (see Treatment for snake bite: first aid), and then at 6 and 12 hours after the time of the suspected snake bite:
- coagulation studies
- INR1
- APTT
- quantitative D-dimer1—at 1 hour after releasing the pressure bandage and 6 hours (but not at 12 hours) after the time of the suspected snake biteIsbister 2022
- fibrinogen concentrationIsbister 2022
- serum creatine kinase concentration.
Use of the snake venom detection kit (VDK) is no longer recommended for the treatment of snake bite in Australia.