Elevated activation markers of coagulation in patients undergoing orthognathic surgery.

Surgery is associated with a variable but increased incidence of postoperative venous thromboembolism (VTE). The risk of VTE after orthognathic surgery is unknown. Recently developed assays for activation markers of blood coagulation allow the detection of a prethrombotic state and may thus help to identify surgical procedures with a risk of postoperative VTE. The pre- and postoperative levels of thrombin-antithrombin complex (TAT) and prothrombin fragment 1+2 (F1+2) were studied in ten patients undergoing orthognathic surgery. Mean levels of TAT and F1+2 were within the normal range preoperatively (TAT:2.6+1.0 microg/L, F1+2:0.8+0.2 nmol/L). A significant increase in both parameters occurred postoperatively (TAT:21.8+21.4 microg/L, P<0.005; F1+2:1.3+0.4, P<0.02). No increase was observed in a control group (n=13) consisting of patients undergoing minor surgical procedures in general anesthesia. Our study shows that a marked activation of the coagulation cascade occurs during orthognathic surgery which warrants further studies on the true incidence of postoperative VTE in patients undergoing orthognathic surgery.