Intraoperative Intravenous and Intra-Articular Plus Postoperative Intravenous Tranexamic Acid in Total Knee Arthroplasty A Placebo-Controlled Randomized Controlled Trial

Background: Combined intraoperative intravenous and intra-articular tranexamic acid (TXA) is 1 of the most effective administration routes to decrease the amount of perioperative blood loss during total knee arthroplasty (TKA). However, the additive effect of postoperative intravenous TXA administration remains unclear. We hypothesized that the postoperative repeated-dose intravenous administration of TXA would provide lower perioperative blood loss. Methods: We performed a double-blinded, placebo-controlled trial involving patients undergoing primary TKA. A total of 100 patients who were managed with combined intraoperative intravenous and intra-articular TXA were randomly assigned to receive 3 postoperative 1,000-mg doses of intravenous TXA (TXA group) or 3 postoperative doses of intravenous normal saline solution (placebo group) in a 1:1 ratio. The prespecified primary outcome was perioperative blood loss calculated from patient blood volume and the difference in hemoglobin from preoperatively to postoperative day 3. A post hoc power analysis showed that the number of patients allocated to either the TXA group (n = 46) or the placebo group (n = 54) possessed >80% power to detect a 200-mL difference in perioperative blood loss. Results: In the intention-to-treat analysis, we found no significant differences in perioperative blood loss between the TXA group and the placebo group through postoperative day 3 (578 +/- 229 compared with 640 +/- 276 mL, respectively; 95% confidence interval for the difference, -40 to 163 mL; p = 0.23). The prevalence of postoperative thrombotic events did not differ between the 2 groups (4.3% compared with 3.7%, respectively; p > 0.99). Conclusions: Postoperative intravenous TXA had no additive effect in reducing perioperative blood loss in patients receiving intraoperative combined intravenous and intra-articular TXA.