Plasma heparin cofactor II, protein C and antithrombin in elective surgery

The coagulation inhibitors heparin cofactor II (HC II), protein C (PC) and antithrombin (AT) were measured in 14 patients undergoing uncomplicated abdominal, orthopedic or vascular surgery. Marked transient decrease of all the inhibitors was found after all surgical procedures, most prominently in vascular surgery. The greatest mean reduction was in HC II. The fall in PC and AT showed a pattern similar to that of albumin. In contrast to some earlier suggestions our results indicated that, except for HC II, the reduction probably was not due to consumption. Redistribution, hemodilution and, probably, reduced synthesis were the most important contributing factors. Serial measurements of the three coagulation inhibitors may be of prognostic value, but the present study's observed mean decrease of c. 25% in abdominal and 50-62% in vascular surgery must be borne in mind. Still lower inhibitor levels suggest consumption and a complicated postoperative course.