Tranexamic acid reduces allogeneic red cell transfusions in patients undergoing total knee arthroplasty: results of a meta-analysis of randomized controlled trials

BACKGROUND: The delayed bleeding associated with total knee arthroplasty (TKA) may be a result of a tourniquet-induced imbalance of the procoagulant and fibrinolytic systems. There are conflicting results in the literature about tranexamic acid (TA) infusion in reducing postoperative blood loss and the number of transfused red cells (RBC) units. A meta-analysis was performed to summarize the results of different research studies. STUDY DESIGN AND METHODS: Randomized controlled trials reported through October 2004 were retrieved, and nine studies met the criteria for meta-analysis. Summary odds ratio (OR) of allogeneic transfusion and a weighted mean difference (WMD) of transfusions per patient in TA-treated group versus placebo group were calculated across studies. RESULTS: The use of TA significantly reduced the proportion of patients requiring blood transfusion (summary OR, 0.10; 95% CI, 0.06-0.18; p < 0.00001) and the number of RBC transfusions per patient (WMD, -1.72; 95% CI, -2.11 to -1.33; p < 0.00001) when compared with patients who received placebo. CONCLUSION: Our meta-analysis shows that the use of TA for patients undergoing TKA is effective in reducing the requirements of allogeneic blood transfusion.