T63.0 + (X20.99)
DESCRIPTION
Boomslang venom is haemotoxic. A consumptive coagulopathy usually sets in within 6–36 hours after the bite with hypofibrinogenaemia and bleeding.
In suspected boomslang bite, a whole blood clotting time is a useful bedside test, especially in rural areas. Place 5 mL of blood in a dry glass test tube and leave at room temperature for 20 minutes. Normal clotting time varies from 5–20 minutes. It is important to repeat these over a few days.
Other investigations include FBC, activated PTT, prothrombin time (INR), fibrinogen, D-dimer and monomers.
Note: Polyvalent antivenom is not effective in boomslang bite.
Boomslang monovalent antivenom
Indicated for all boomslang bites with evidence of haemotoxicity
Obtainable from South African Vaccine Producers (tel: +2711 386-6063/2/78 or afterhours 0716809897 or 0828842971). See full details in the package insert.
Caution
Never administer antivenom without being fully prepared to manage acute anaphylaxis.
- Boomslang monovalent antivenom, slow IV infusion, 20 mL diluted in 50–100 mL sodium chloride 0.9% or dextrose 5%, administered over 5–10 minutes.LoEIII [9]
- The dose of antivenom is the same for adults and children.
- Spontaneous systemic bleeding should stop within 15–30 minutes and blood coagulability be restored within 6 hours, after administering antivenom.
- Re-evaluate regularly, and if after 6 hours there is ongoing evidence of coagulopathy, a repeat dose of 10 ml may be considered.