Activation of coagulation and fibrinolysis in microsurgical reconstructions in the lower extremities

Coagulation and fibrinolysis activities in relation to trauma, surgery and thrombosed microanastomoses were studied during free-flap surgery in eight patients with lower-extremity defects due to recent trauma or chronic ulcer s. One patient had an intraoperative thrombosis, and three more patients re quired reoperations on the same day due to postoperative thromboses; one of these also required a second reoperation due to flap failure. The baseline level of fibrinogen was slightly elevated in all patients except one, and was significantly higher in the patients who underwent reoperation. At the end of the primary surgery, distinct thrombin generation (TAT and F1 + 2) w as seen in three patients with excessive bleeding, and all three later unde rwent reoperations. One of these patients generated excessive thrombin on t he eighth postoperative day, upon removal of a necrotic flap. Thrombin gene ration (Fl + 2) was also seen at baseline in the patient with the intraoper ative thrombosis, and persisted on the first postoperative day. D-dimer at baseline was higher in patients with recent trauma, and in two of these, bo th of whom underwent reoperations on the same day, D-dimer remained high pe rioperatively. Resistance to fibrinolysis with increased PAI-1 levels was s een in these two patients at the time of reoperation. In all, TAT and F1 2 were associated with the threat of flap failure. A preoperative hypercoag ulable state and excessive bleeding during the operation were predictors of reoperation. The markers for coagulation and fibrinolysis could be used pr eoperatively to target antithrombotic control, and postoperatively to detec t the threat of flap failure. Meticulous haemostasis during surgery might h elp to diminish the need for reoperations. (C) 2001 The British Association of Plastic Surgeons.