Effects of puff-adder venom on coagulation, fibrinolysis and platelet aggregation in the baboon.

Abstract

S. BRINK, SUMMARY The in vitro and in vivo haematological effects of puff­ adder (Bitis arietans) venom in the baboon (Papio ursinus) with regard to its effect on coagulation, fibrinolysis and platelet aggregation were studied. There is a delay in the intrinsic coagulation mechanism with fibrinolysis and in vitro fibrinogenolysis. Normal human platelets demon­ strated an extreme susceptibility to puff-adder venom in vitro. The aggregation of platelets with small dosages of venom was irreversible. The effect is related to the dosage, and appears to be the result of multiple enzyme activities, some of which are heat-labile. In minimal amounts there is evidence of con­ sumption of blood coagulation factors with sustained thrombocytopenia, but no fibrinolysis, where heparin therapy might have a beneficial effect. With larger dosages of venom the thrombocytopenia, haemorrhagic effects and shock are not prevented or corrected by heparin and