Abstract
Background
91% of blood loss in Total Hip Replacement (THR) occurs in the period after skin closure and the first 24 post-operative hours. TRAC-24 was established to identify if an additional 24-hour post-operative oral regime of Tranexamic acid (TXA) is superior to a once-only intravenous dose at surgery.
Methods
This was a prospective, phase IV, single centered, open label, parallel group controlled trial on patients undergoing primary elective THR. A history of thromboembolic or cardiovascular disease were not exclusion criteria. The primary outcome was indirect calculated blood loss at 48 hours (IBL). 534 patients were randomized on a 2:2:1 ratio over three different groups. Group 1 received an intravenous dose of TXA at the time of surgery and an additional 24-hour post-operative oral regime, Group 2 only received the intra-operative dose and Group 3 did not receive any TXA.
Results
233, 235 and 66 patients were recruited to groups 1,2 and 3. All groups had comparable baseline characteristics. 3.2% of all patients had previous thromboembolism and 5.4% had previous cardiac stenting. Group 3 mean (SD) IBL was 1371 (630) ml whereas group 1 and 2 combined had a mean (SD) IBL of 846 (471), p<0.001. There was no overall difference in IBL between group 1 and group 2, but subgroup analysis observed 12% less blood loss in group 1 than group 2 in the 36 patients weighing >100kg. No differences in mortality or thromboembolic events were observed in any group.
Conclusion
The use of a single, intravenous, peroperative, 1-gram dose of Tranexamic acid decreased the total blood loss associated with THA by 38%. The addition of another 24-hours oral tranexamic acid did not provide additional benefit but further study on the effect of patient weight is required. Tranexamic acid is safe in patients with history of thromboembolic and cardiovascular disease.
