Delayed Administration of Apixaban, but Not Rivaroxaban, Reduces Transfusion Risk without Increasing Thromboembolic Rates following Revision Total Hip Arthroplasty.

Abstract

The optimal timing for initiating direct oral anticoagulants (DOACs) for venous thromboembolism (VTE) prophylaxis following revision total hip arthroplasty (rTHA) is unknown. This study compared rates of thromboembolic and bleeding complications between patients beginning prophylactic courses of apixaban or rivaroxaban on postoperative day (POD) zero versus POD one. A national healthcare database including approximately 25% of all surgeries performed in the United States was used to identify patients who underwent aseptic both-component rTHA between 2016 and 2023. Patients receiving apixaban or rivaroxaban for chemoprophylaxis after rTHA on POD zero were compared to patients who received the same anticoagulant on POD one. Primary outcomes included 90-day rates of postoperative bleeding complications (acute anemia, hematoma, hemorrhage, and transfusion) and thromboembolic complications (deep vein thrombosis [DVT], pulmonary embolism [PE], stroke, and myocardial infarction [MI]). Multivariable regression analysis was used to assess differences between cohorts. In total, 5,607 patients were identified. Of the 2,990 (53.33%) patients administered apixaban, 646 (21.61%) received anticoagulation beginning POD zero compared to 2,344 (78.39%) on POD one. Of the 2,617 (46.67%) patients given rivaroxaban, 598 (22.85%) received anticoagulation on POD zero compared to 2,019 (77.15%) on POD one. Patients receiving apixaban on POD one had lower odds of transfusion (adjusted odds ratio [aOR]: 0.702, 95% confidence interval [CI]: 0.57 to 0.862, P = 0.001) and acute anemia (aOR: 0.890, 95% CI: 0.792 to 0.999, P = 0.049) when compared to POD zero patients. Additionally, patients receiving apixaban on POD one were associated with similar odds of DVT and PE, but with reduced odds of an MI (aOR: 0.338, 95% CI: 0.171 to 0.668, P = 0.002). Rivaroxaban patients demonstrated no significant differences in bleeding outcomes, transfusion requirements, or thromboembolic complications between POD zero and POD one administration. Administration of apixaban on POD one was associated with a reduced risk of transfusion without an increased risk of thromboembolic complications among patients undergoing rTHA. The timing of rivaroxaban administration was not associated with postoperative bleeding, transfusion risk, or thromboembolic complications.