[Classification and pathogenesis of thrombohemorrhagic events connected with surgery. Intravascular coagulation in...

This disorders secondary to haemostasis which complicate surgery can be clinically subdivided into haemorrhagic and thrombotic complications. Haemorrhagic complication may present as a generalized haemorrhage that almost always occurs in the infra-operative period, or as a localized haemorrhage (mainly at the level of the gastroenteric tube). As this is seen in the postoperative period it can be defined as late. Thrombotic complication may present with a picture of phlebothrombosis, usually clinically evident at the lower extremities, or with a clinical picture of sudden occlusion of pulmonary circulation, namely pulmonary embolism. Pathogenetically, these two groups of complications may now be lumped together in view of the fact that surgery always causes stress in haemostatic function with thus reaches a condition of largely atent balance but which may be upset in either of two possible directions: hypohaemostatic or haemorrhagic on the one hand, and hyperhaemostatic and thrombotic on the other. The point in common is represented by the activation of the clotting system (platelet component included) followed or accompanied by anticlotting mechanisms (mainly the fibrinolytic). Whether the complication will be thrombotic or haemorrhagic depends on the prevalence of the former of the latter. These conclusions are based on an experimental clinical analysis of the phenomena that occur within the haemostatic function throughout the surgical process but principally at the operating stage itself, and are indirectly confirmed ex juvantibus in the proven effectiveness of heparinic prophylaxis. Therapeutic and prophylactic approaches are put forward on the basis of this unified pathogenetic concept.