Background: Low molecular weight heparin (LMWH) has been the standard treatment for preventing venous thromboembolism after total joint arthroplasty. However, the evidence supporting specific LMWH dosing regimens is limited.
Objectives: This study assessed the efficacy and safety of three enoxaparin dosing regimens to prevent venous thromboembolism.
Methods: Participants undergoing hip or knee replacement were randomly assigned to receive 20 mg of enoxaparin 6 h postoperatively (Group A), 40 mg 6 h postoperatively (Group B), or 40 mg 12 h postoperatively (Group C). The primary outcomes included thromboembolic and major bleeding events within 3 months, while the secondary outcomes comprised ecchymosis, wound exudation, drainage volume, allogeneic red blood cell transfusion, and first postoperative day hemoglobin levels.
Results: A total of 536 patients were analyzed. The occurrence of thromboembolic events was comparably low across all groups. Group C exhibited the lowest postoperative ecchymosis rate at 19.3%, significantly less than Group A (32.8%, p = 0.004) and Group B (37.7%, p < 0.001). Ecchymosis rates were about double in Group A and 1.5 times higher in Group B compared to Group C. Significant differences were also observed in 24-hour and total postoperative drainage volumes, with Group B having higher volumes than the other groups.
Clinical trial registration: This trial was prospectively registered at the China Clinical Trials Registry (registration date: November 14, 2021; registration number: ChiCTR2100053191).
Conclusion: No significant differences in venous thromboembolism rates were seen between the tested enoxaparin dosing regimens after total joint arthroplasty. The 40 mg dose administered 12 h after surgery was associated with reduced postoperative ecchymosis and drainage volumes without an increased thrombosis risk, suggesting it is a safer and more effective option than earlier or lower dosages.
Keywords: Dosing regimens; Drainage volume; Ecchymosis; Low molecular weight heparin; Total joint arthroplasty; Venous thromboembolism prophylaxis.
© 2024. The Author(s).