Protein C: a new plasma protein related to postoperative hypercoagulability.

Protein C is a vitamin-K dependent plasma protein, whose activation is catalyzed by alpha-thrombin. Unlike vitamin-K dependent coagulation factors, activated Protein C is an anticoagulant enzyme. Purpose of the present study was to evaluate the pathophysiology of Protein C in patients undergoing minor and major elective surgery. A third group of patients were operated for cancer of the gastrointestinal tract. Protein C levels have significantly decreased in all patients in third postoperative day, while this decrease occurred since the first postoperative day in the case of cancer patients. This suggests that Protein C is consumed after surgery in its anticoagulant and profibrinolytic activity. The acquired Protein C deficiency may be related to postoperative hypercoagulability and increased risk of deep vein thrombosis.