Studies on Australian snake venoms, Part II: The haematological effects of brown snake (Pseudonaja) species in the dog.

The haematological effects of Brown Snake (Pseudonaja) species (textilis, affinis, nuchalis) were studied in anaesthetised, mechanically ventilated dogs. Marked thrombocytopenia, depletion of serum fibrinogen and prolonged prothrombin and activated partial thromboplastin time, were recorded at 5 to 10 and 30 to 40 minutes after intravenous envenomation. Fibrin degradation products were not elevated. Because these haematological effects occurred simultaneously with cardiovascular depression (previously reported), we postulate that hypotension sometimes observed in human envenomation may be due to intravascular coagulation with myocardial ischaemia.