Course of molecular hemostatic markers during and after different surgical procedures

Study Objective: To establish the most vulnerable time of thrombi formation with regard to the plasmatic (noncellular) part of the coagulatory and fibrinolytic systems. Design: Nonrandomized observational study. Setting: A surgical and an orthopedic unit and the central laboratory of a university hospital. 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; subtotal thyroid resection: 15 patients. Interventions: The time course of 11 procoagulatory and fibrinolytic parameters 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 postoperative days 1, 2, 3, 4, and 5. Measurements and Main Results: The coagulation samples were centrifuged within 1 hour of collection of 2,300g for 15 minutes at 4 degrees C. Hemoglobin, hematocrit, platelets, fibrinogen, prothrombin time, activated partial thromboplastin time, thrombin time, antithrombin III, and protein C were determined immediately on laboratory arrival of the samples. The samples were aliquoted at -70 degrees C. They were thawed within 2 weeks and prepared for 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 decreases until normal values are reached around the fifth postoperative day. Parameters displaying the greatest changes are TAT-complexes and D-dimers. The type of surgery with the most pronounced changes was total hip replacement, followed by hemicolectomy, cholecystectomy, and subtotal thyroid resection. Conclusion: The total hip replacement and hemicolectomy groups show similar 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 postoperatively. (C) 2000 by Elsevier Science Inc.