Administering aspirin, rivaroxaban and low-molecular-weight heparin to prevent deep venous thrombosis after total knee arthroplasty.

This study aimed to compare the efficacy and safety of aspirin, rivaroxaban and low-molecular-weight heparin (LMWH) for post total knee arthroplasty (TKA) deep vein thrombosis (DVT) prophylaxis. Between July 2011 and July 2013, a prospective randomized controlled trial was performed on 324 patients with osteoarthritis who underwent primary unilateral TKA. Twelve hours after the surgery, Group A was given oral rivaroxaban at a dose of 10 mg/day. Group B was given subcutaneous LMWH at a dose of 4000 AxaIU (0.4 ml)/day and Group C was given oral aspirin at a dose of 100 mg/day. All three groups were treated for 14 days, and all of the patients were followed for 4 weeks. The incidence of DVT, dominant/hidden blood loss, the incidence of wound complications and the incidence of subcutaneous ecchymosis in the affected extremities were compared between the three groups. The incidence of DVT was lower in Group A compared with the other two groups [3 (2.94%) vs. 14 (12.50%), P = 0.029; 3 (2.94%) vs. 18 (16.36%), P = 0.017]. However, hidden blood loss [1.71 (1.19-2.97) vs. 1.18 (0.77-2.31), P = 0.009; 1.71 (1.19-2.97) vs. 1.30 (0.61-2.43), P = 0.004] and wound complications [5 (4.90) vs. 3 (2.67), P = 0.027; 5 (4.90) vs. 2 (1.82), P = 0.014] were more common in Group A than in the other groups. There were no significant differences between Group B and Group C in the incidence of DVT [14 (12.50%) vs. 18 (16.36%), P = 0.831], hidden blood loss [1.18 (0.77-2.31) vs. 1.30 (0.61-2.43), P = 0.327] or wound complications [3 (2.67) vs. 2 (1.82), P = 0.209]. No significant differences in the incidence of limb swelling were found between the three groups [38 (37.25%) vs. 28 (25.00%) vs. 24 (21.82%), P = 0.247]. Group A had a higher incidence of subcutaneous ecchymosis in the affected extremities than Group C [74 (72.55%) vs. 54 (49.09%), P = 0.039], but there were no significant differences between Groups A and B [74 (72.55%) vs. 62 (55.36%), P = 0.193] or between Groups B and C [62 (55.36%) vs. 54 (49.09%), P = 0.427]. Rivaroxaban has a positive anticoagulation effect but leads to increases in both postoperative blood loss and wound complications in patients. Hence, clinicians using rivaroxaban for anticoagulant therapy should closely monitor the changes in the hemoglobin level and wound healing and promptly supplement blood volume and provide other symptomatic and supportive treatments. No significant difference in post-TKA DVT prophylaxis was found between aspirin and LMWH, and the former can be used as part of a multimodal anticoagulation therapy.