Course of molecular hemostatic markers during and after different surgicalprocedures

Study Objective: To establish the most vulnerable time of thrombi formation with regard to the plasmatic (noncellular) part of the coagulatory and fib rinolytic systems. Design: Nonrandomized observational study. Setting: A su rgical and an orthopedic unit and the central laboratory of a university ho spital. Patients: 61 consenting ASA physical status I and II inpatients undergoing four different types of surgery: total hip replacement (THR): 16 patients; hemicolectomy: 15 patients; endoscopic cholecystectomy: 15 patients; subtot al thyroid resection: 15 patients. Interventions: The time course of 11 procoagulatory and fibrinolytic parame ters was examined during the different types of surgery. Blood samples were drawn on the day before surgery, directly before the induction of general anesthesia, 1 to 2 hours postoperatively, and on the mornings of postoperat ive days 1, 2, 3, 4, and 5. Measurements and Main Results: The coagulation samples were centrifuged wit hin 1 hour of collection of 2,300g for 15 minutes at 4 degrees C. Hemoglobi n, hematocrit, platelets, fibrinogen, prothrombin time, activated partial t hromboplastin time, thrombin time, antithrombin III, and protein C were det ermined immediately on laboratory arrival of the samples. The samples were aliquoted at -70 degrees C. They were thawed within 2 weeks and prepared fo r the following assays: thrombin-antithrombin III complexes (TAT-complexes) , D-dimers, and plasminogen activator inhibitor type 1. Maximum activation of coagulation is not reached until 2 hours postoperatively and slowly decr eases until normal values are reached around the fifth postoperative day. P arameters displaying the greatest changes are TAT-complexes and D-dimers. T he type of surgery with the most pronounced changes was total hip replaceme nt, followed by hemicolectomy, cholecystectomy, and subtotal thyroid resect ion. Conclusion: The total hip replacement and hemicolectomy groups show si milar and strong activation of the procoagulatory and fibrinolytic systems. Much less pronounced are the changes during endoscopic cholecystectomy and subtotal thyroid resection. Maximum activation occurs 1 to 2 hours postope ratively. (C) 2000 by Elsevier Science Inc.