[Effects of premedication, narcosis and surgery on the coagulation and fibrinolysis systems and the platelets. The influence of dextran and hydroxyethyl starch (hes) during and after operation (author's transl)].

Patients who had undergone orthopaedic surgery were investigated. The changes attributable to premedication and narcosis were characterized by a primary fibrinolysis which was accompanied by a slight hypercoagulability. This increased fibrinolytic activity was more pronounced immediately after the beginning of the operation. The post operative changes are characterized by increased ADP-induced aggregation, increased release of platelet factors 3 and 4 and hypercoagulability with reduced fibrinolysis. The reduction in platelets during the operation could be prevented due to the influence of dextran and hydroxyethyl starch (HES). It came further to a slight increase in the activity of factor VII, to an increased fibrinogen polymerization and also to an increased release of platelet factor 4.