A prospective, double-blind, randomised controlled trial comparing oral versus intravenous tranexamic acid for blood loss reduction in primary total knee arthroplasty.

Abstract

Total knee arthroplasty (TKA) is associated with significant perioperative blood loss. While intravenous tranexamic acid (TXA) effectively reduces bleeding, oral TXA may offer comparable efficacy with economic and logistical advantages. We assessed whether oral TXA is non-inferior to intravenous TXA for reducing blood loss following primary total knee arthroplasty. This prospective, double-blind, randomised controlled trial included 60 patients undergoing primary cemented TKA between September 2019 and March 2020. Patients were randomised (1:1) to receive either 2 g oral TXA administered 2 h preoperatively or 1 g intravenous TXA at induction of anaesthesia. Both groups received matched placebos to maintain blinding. The primary outcome was reduction in haemoglobin concentration from baseline to postoperative day 5. Secondary outcomes included calculated total blood loss, drain output, transfusion rate, length of hospital stay, and adverse events. Statistical analysis followed intention-to-treat principles. Mean haemoglobin reduction was 2.60 ± 0.95 g/dL in the oral TXA group versus 2.71 ± 1.18 g/dL in the intravenous group (mean difference =  - 0.11 g/dL; 95% CI: - 0.64 to 0.42; p = 0.68). Calculated total blood loss was 802.8 ± 286.4 mL versus 848.9 ± 421.5 mL respectively (p = 0.62). Drain output on postoperative day 1 was higher with oral TXA (256.7 ± 129.1 vs 192.5 ± 89.9 mL; p = 0.03) but similar on day 2 (130.1 ± 61.9 vs 119.3 ± 50.8 mL; p = 0.46). Transfusion rates were 10.0% (3/30) versus 3.3% (1/30) (p = 0.31). No thromboembolic events occurred in either group. Oral TXA administered preoperatively demonstrates non-inferiority to intravenous TXA for reducing perioperative blood loss in primary TKA. Despite a clinically relevant but statistically non-significant trend toward higher transfusion rates with oral TXA in this small sample, oral administration represents a safe and substantially more cost-effective alternative (80% cost savings), particularly suitable for resource-constrained healthcare environments and ambulatory surgery settings.