[Direct action of extracorporeal circulation on platelets and coagulation factors]

Concerning a study carried out in 250 patients, the authors confirm the classical notions concerning the fall in platelets, fibrinogenesis, factor II, XII AT3 and plasminogen during ECC. A more precise study of platelet levels shows important variations depending on the patients, whereas the length of time of ECC, the degree of importance of aspiration the first minutes of ECC, appear to be aggravating factors. There is no correlation between the type and the length of the circuit. Furthermore, from the morphological standpoint, thrombocytic changes are also noted. The same can be said of platelet function. In the last part of the work, the authors studied the causes of platelet consumption and their prevention. On the whole, and in practice, consumption of coagulation factors during ECC remains a little disturbing. It is, however, worth continuing to study their prevention.