Factor Xa Inhibitor Dosing in Postoperative Joint Replacement Patients: A Retrospective Comparison between Full-Dose and Half-Dose Protocols

Introduction Factor Xa inhibitors (FXaI), a type of direct oral anticoagulant (DOAC), are medications used in patients at risk for, and after venous thromboembolic (VTE) events. The aim of this retrospective cohort study is to investigate the relationship between two postoperative FXaI dosing regimens and the occurrence of significant bleeding and VTE events following total joint arthroplasty (TJA). Methods This study included patients who underwent primary TJA and were preoperatively receiving apixaban or rivaroxaban. Group A included patients who resumed a half-dose FXaI for seven days postoperatively prior to resuming their preoperative dose. Group B resumed their preoperative dose the evening of surgery. The measured outcomes were significant bleeding or VTE events within 6 months of surgery. Results There were 332 patients included in this study; (Group A=98, (29.5%), Group B=234, (70.5%)). Group A experienced a lower number of significant bleeding events compared to Group B; however, this difference was not statistically significant (Group A: 6 (6.1%) vs Group B: 17 (7.3%), p=0.708.) Group B experienced a higher incidence of VTE compared to group B, however, the difference was not statistically significant (Group A: 2 (2.0%) vs Group B: 3 (1.3%), p=0.605). When adjusting for patient demographics, there was no statistically significant difference in bleeding (P=0.424) or VTE outcomes (P=0.774). Conclusion There was no statistically significant difference in postoperative bleeding and VTE events between patients who were restarted on a half-dose or full-dose regimen of apixaban or rivaroxaban following TJA.