Activation of coagulation and fibrinogen loss after using an extracorporeal circulation

Alterations of the coagulation potential of heparinized blood after using an extracorporeal circulation have been studied by means of a toluidine blue-calcium chloride reagent. This technique was originally used to detect the effect of activation by contact on the coagulation mechanism in heparinized blood. It has been shown that it also detects, in the presence of heparin, the clotpotentiating effect of blood cell contents liberated in vitro by mechanical trauma to blood.