Use of tranexamic acid for an effective blood conservation strategy after total knee arthroplasty

We have investigated the effect of treatment with tranexamic acid, an inhib itor of fibrinolysis, on blood loss, blood transfusion requirements and blo od coagulation in a randomized, double-blind, placebo-controlled study of 4 2 patients after total knee arthroplasty. Tranexamic acid 15 mg kg(-1) (n = 21) or an equivalent volume of normal saline (n = 21) was given 30 min bef ore surgery and subsequently every 8 h for 3 days. Coagulation and fibrinol ysis values, blood loss and blood units administered were measured before a dministration of tranexamic acid, 8 h after the end of surgery and at 24 an d 72 h after operation. Coagulation profile was examined (bleeding time, pl atelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), plasminogen, beta-thromboglobulin and fibrinogen). Fibrinolysis was evaluated by measurement of concentrations of D-dimer and fibrinogen degra dation products (FDP). Total blood loss in the tranexamic acid group was 67 8 (sD 352) mi compared with 1419 (607) mi in the control group (P < 0.001), and occurred primarily during the first 24 h after surgery. Thirteen patie nts received 1-5 u. of packed red blood cells in the control group compared with two patients in the tranexamic acid group, who received 3 u. (P < 0.0 01). Postoperative packed cell volume values were higher in the tranexamic acid group despite fewer blood transfusions. Postoperative concentrations o f plasminogen were decreased significantly in the tranexamic acid group (P < 0.001). Platelet count, PT, aPTT, bleeding time, beta-thromboglobulin, fi brinogen and FDP concentrations did not differ between groups, but D-dimer concentrations were increased in the control group. Thromboembolic complica tions occurred in two patients in the control group compared with none in t he tranexamic acid group.