Efficacy of topical tranexamic acid within a blood-saving programme for primary total hip arthroplasty: a pragmatic, open-label randomised study

Abstract

Background: Total hip arthroplasty entails considerable peri-operative blood loss, which may lead to acute post-operative anaemia and red blood cell transfusion. This study was aimed at assessing whether the addition of topical tranexamic acid to our ongoing blood-saving protocol for total hip arthroplasty was effective and safe.

Materials and methods: A pragmatic, prospective, open-label randomised study of patients scheduled for total hip arthroplasty at a single centre was conducted. Consecutive patients were randomly assigned to receive topical tranexamic acid (2 g) at the end of surgery (tranexamic group, n=125) or not (control group, n=129). A restrictive transfusion protocol was applied. Outcome measures were red blood cell loss at 24 hours after surgery, in-hospital transfusion rate, and incidence of thromboembolic complications.

Results: Topical tranexamic acid was effective in reducing both red cell loss (mean difference: 138 mL [95% CI 87-189 mL]; p<0.001) in the 24h after surgery and in-hospital transfusion rates (12 vs 32.6%, for the tranexamic acid and control groups, respectively; p<0.001; relative risk=0.37 [95% CI 0.22-0.63]). However, relative red cell loss and transfusion rates were higher in females than in males, irrespectively of tranexamic acid use. The beneficial effect of tranexamic acid on transfusion was restricted to patients with pre-operative haemoglobin ≥13 g/dL (5.1 vs 24.8%; p<0.001). Topical tranexamic acid was well tolerated and no clinically apparent thromboembolic complications were witnessed.

Discussion: The use of topical tranexamic acid after hip arthroplasty reduced red cell loss and transfusion rates; the efficacy of this strategy may be improved by reinforcing both pre-operative haemoglobin optimisation and adherence to the practice of transfusing single units of red cells.

Figure 1

Patients’ flow diagram.

Figure 2

Effects of topical tranexamic acid administration on relative RBC mass loss (A) and transfusion rate (B), according to gender and preoperative haemoglobin. Estimated RBC mass loss at 24 hours after surgery is depicted as percentage of estimated preoperative RBC mass. Hb: haemoglobin (g/dL); RBC: red blood cells; *p<0.005, tranexamic acid vs control; **p=0.055, tranexamic acid vs control; #p<0.01, female vs male; ##p<0.001, Hb <13 g/dL vs Hb ≥13 g/dL.