The effect of tourniquet application, tranexamic acid, and desmopressin onthe procoagulant and fibrinolytic systems during total knee replacement

Study Objective: To assess the influence of tourniquet inflation-deflation as well as desmopressin and tranexamic acid (TA) administration on prothrom lrin fragment 1.2, fibrinogen, plasmin antiplasmin complex, and D-dimer con centrations during total knee replacement. Design: Randomized, placebo-controlled study. Setting: Large referral hospital. Patients: 30ASA physical status I, II, and III patients undergoing total kn ee replacement. Interventions: Patients were randomized to one of three treatment groups. P atients received either tranexamic acid, desmopressin, or an equal volume o f saline, intravenously. Measurements and Main Results: Cubital blood was drawn immediately before i nduction of anesthesia, I hour after tourniquet application, and 2 and 15 m inutes after tourniquet deflation. . Fibrinogen and D-dimer levels were mea sured using the Clauss Method and latex agglutination, respectively. Plasmi n antiplasmin complex and prothrombin fragment 1.2 levels were measured by enzyme-linked immunosorbent assay (ELISA). All assays were performed in dup licate, and intra-assay variability, was documented. No statistically signi ficant difference in fibrinogen, D-dimer, plasmin antiplasmin complex, or p rothrombin fragment 1.2 levels was demonstrated among the groups. Similarly , within each group there were no statistically significant differences in the variables studied. However; despite the lack of statistical significanc e, when compared with their levels during tourniquet application, an increa se in D-dimer and plasmin antiplasmin complex levels was observed in all th ree groups at 2 and 15 minutes after tourniquet release. In contrast, no in crease in prothrombin fragment 1.2 generation was noted. Significantly more allogeneic blood was transfused in the Control and Desmopressin Groups whe n compared with the tranexamic arid group (p < 0.02). Conclusions: No evidence of tourniquet-induced fibrinolysis or thrombin gen eration was demonstrated in the systemic circulation. Desmopressin and tran examic acid had no significant effect on the variables measured. (C) 2001 b y Elsevier Science Inc.