RESUMO
PURPOSE: Despite the documented blood-saving effects of tranexamic acid (TNA) in total knee arthroplasty (TKA), the question whether clinical values of TNA are identical in unilateral and bilateral TKAs remains unclear. This study was undertaken to determine the clinical values of TNA in unilateral and simultaneous bilateral TKAs under a contemporary blood-saving protocol in terms of efficacy (total blood loss and transfusion rate) and safety (the incidences of symptomatic deep vein thrombosis and pulmonary embolism). METHODS: One hundred and eighty unilateral and 146 bilateral TKA patients were randomized into TNA group or control group. In unilateral TKA patients, TNA (10 mg/kg) was administered intravenously 20 min before tourniquet deflation and repeated 3 h after surgery. In bilateral TKA patients, one more dose (10 mg/kg) was given before tourniquet deflation in the second TKA. A contemporary blood-saving protocol was applied to all patients. The TNA and control groups were compared separately in unilateral and bilateral TKA patients for the efficacy and safety variables. RESULTS: In unilateral TKA patients, the TNA group had less total blood loss (905 vs. 1,018 mL, p = 0.018) than the control group, but there was no difference in the allogenic transfusion rate (1 vs. 7 %, n.s.). In bilateral TKA patients, the TNA group showed no differences in total blood loss (1,282 vs. 1,379 mL, n.s.), but a significant reduction in the allogenic transfusion rate (7 vs. 27 %, p = 0.002). No symptomatic deep vein thrombosis or pulmonary embolism was found in all patients. CONCLUSION: This study demonstrates that the use of TNA reduces total blood loss, but the effects on the transfusion rate can differ depending on the type of TKAs (unilateral vs. bilateral) and the blood-saving protocols.