High-dose intra-articular versus weight-based peri-articular tranexamic acid in primary total knee arthroplasty: a randomized controlled trial.

BACKGROUND

Intra-articular (IA) and peri-articular (PA) tranexamic acid (TXA) are used to reduce blood loss after total knee arthroplasty (TKA), but comparative evidence is limited because dosing and administration protocols vary. This study compared weight-based PA TXA at 10 mg/kg with fixed-dose IA TXA at 3 g.

METHODS

In this prospective, randomized, assessor-blinded trial, 80 patients undergoing primary unilateral TKA were allocated 1:1 to PA TXA at 10 mg/kg or IA TXA at 3 g. The co-primary outcomes were transfusion-adjusted calculated blood loss at 72 h and allogeneic packed red blood cell (PRBC) transfusion. Secondary outcomes included unadjusted calculated blood loss, hematocrit reduction, drain output, transfused PRBC units, and adverse events. Analyses followed the intention-to-treat principle.

RESULTS

Transfusion-adjusted calculated blood loss was lower in the IA group than in the PA group (537 ± 282 vs 754 ± 476 mL; mean difference [PA minus IA], 218 mL; 95% CI, 43-393 ml; P = 0.019). PRBC transfusion was required in 3 of 40 patients (7.5%) in the IA group and 11 of 40 (27.5%) in the PA group (risk ratio [PA vs IA], 3.67; 95% CI, 1.11-12.16; P = 0.037). Unadjusted calculated blood loss, hematocrit reduction, and drain output were similar between groups. No symptomatic deep-vein thrombosis or pulmonary embolism was identified.

CONCLUSION

IA TXA at 3 g was associated with lower transfusion-adjusted calculated blood loss and fewer transfusions than PA TXA at 10 mg/kg, while secondary blood-loss measures were similar between groups.