Weight-based tranexamic acid lowers the risk of postoperative blood loss and transfusion requirements compared with fixed-dose regimen in revision knee arthroplasty: a comparative study.

Background: Intravenous tranexamic acid (TXA) dosing regimens differ substantially across studies, varying from fixed doses (e.g., 1-2 g) to weight-based protocols (e.g., 10-20 mg/kg). This study aimed to compare postoperative blood loss, transfusion rates, in-hospital mortality, and complications between fixed-dose and weight-based TXA regimens in revision total knee arthroplasty (rTKA).

Materials and methods: This retrospective comparative study included 298 patients who underwent rTKA between June 2004 and May 2024. Patients were divided into three groups: (1) the no TXA group; (2) the fixed-dose TXA group, in which patients received an intravenous infusion of 1 g TXA before skin incision and a topical application of 1 g; and (3) the weight-based TXA group, in which patients received a weight-adjusted dose of 20 mg/kg/h TXA intravenously and a topical application of 1 g. We analyzed the maximum decrease in hemoglobin (Hb) levels, postoperative transfusion rate, and the incidence of in-hospital mortality and complications.

Results: The weight-based TXA group demonstrated a lower maximal decrease in Hb compared with both the no TXA (18.22 g/L versus 26.09 g/L, p < 0.001) and fixed-dose TXA (18.22 g/L versus 24.69 g/L, p < 0.001) groups. Both the fixed-dose TXA and weight-based TXA groups exhibited lower postoperative transfusion rates compared with the no TXA group (p < 0.001). The weight-based TXA group showed a lower postoperative transfusion rate compared with the fixed-dose TXA group (p = 0.022). Although the incidence of deep vein thrombosis (DVT) among the three groups was statistically significant (p = 0.038), pairwise comparisons between groups did not reveal statistically significant differences (all p > 0.05).

Conclusions: Weight-based dosage of TXA significantly reduced postoperative blood loss and transfusion requirements in rTKA compared with fixed-dose TXA regimen. A weight-based TXA regimen should be considered to effectively minimize postoperative blood loss and decrease transfusion requirements.

Level of evidence: Level 3, non-randomized observational study.