Further Experience With the Use of Thrombin as a Hemostatic Agent

We have recently reported animal experiments1 on the use of purified thrombin2 as a hemostatic agent. We are now able to obtain thrombin solutions free of bacteria, and with minor loss of activity, by use of fritted glass filters.3 We wish to report additional toxicity experiments; also preliminary experience with the use of thrombin in a small group of human cases.Toxicity Experiments. As pointed out previously,1 thrombin, applied to operative surfaces, is non-toxic. Numerous other toxicity experiments with thrombin have since been performed, and a small group of these is presented below.(1) Intramuscular administration. An injection of 6000 units into the thigh muscles of an adult rat produced no local thrombosis, and no clinical evidence of toxicity. Blood samples drawn several hours later showed no alteration in the plasma fibrinogen or prothrombin levels.(2) Intraperitoneal administration. An injection of 6000 units of thrombin (4 cc) caused some uneasiness in a 300 g rat, possibly because the soluti...