Safety and efficacy of intra-articular injection of tranexamic acid in total knee arthroplasty.

Tranexamic acid was intra-articularly injected in total knee arthroplasty (TKA) to reduce blood loss and transfusion. However, no single study has been large enough to definitively determine whether it is safe and effective. To determine the safety and efficacy of intra-articular tranexamic acid in TKA, the authors searched various databases for relevant randomized controlled trials. Mean difference (MD) in total blood loss, risk ratio (RR) for transfusion, and complication rate in the tranexamic acid-treated group vs the placebo group were calculated. Seven randomized controlled trials, including 622 patients (174 men and 448 women), were identified. All 7 placebo-controlled randomized trials had a low risk of bias. The pooled results showed a positive effect of tranexamic acid in all treatment groups, with significant reduction in total blood loss (MD, -396.42 mL [95% confidence interval (CI), -629.64 to -163.20]; P=.0009). However, there was significant heterogeneity in the finding (chi-square=27.16, df=3, I(2)=89%; P<.00001) among studies. The pooled results indicated that 5.8% (18 of 309) of tranexamic acid-treated patients required transfusion compared with 27.2% (85 of 313) of placebo-treated patients. This difference was significant (RR, 0.22; 95% CI, 0.14-0.35; P<.00001). There was no significant difference between the groups in the incidence of deep venous thrombosis (RR, 0.83; 95% CI, 0.35-1.98; P=.68) or pulmonary embolism (RR, 0.54; 95% CI, 0.10-2.85; P=.46). In all, intra-articular tranexamic acid significantly reduced total blood loss, drainage, reduction of hemoglobin, and the need for transfusion without increasing the incidence of deep venous thrombosis and pulmonary embolism. Intra-articular tranexamic acid is safe and efficacious in TKA.