Abstract
Introduction
Patients undergoing total hip arthroplasty (THA) stand in the danger, a particularly high risk for venous thromboembolism (VTE). Fondaparinux and edoxaban, which inhibit FXa, indirectly and directly, respectively, have been used for prevention of VTE after THA in Japan. The aim of this study was to compare the efficacy of fondaparinux and edoxaban for VTE after elective THA in Japanese patients.
Materials and methods
We randomly assigned 320 patients underdoing elective cemented THA to receive postoperative 2.5 mg fondaparinux once daily for first postoperative 3 days and 1.5 mg once daily for the subsequent 7 days (FPX group) [1], postoperative 15 mg edoxaban once daily for postoperative 10 days (EDO15mg group), 30 mg edoxaban once daily for postoperative 10 days (EDO30mg group), and 30 mg edoxaban once daily for first postoperative 3 days and 15 mg once daily for the subsequent 7 days (EDOmix group). Deep venous thrombosis (DVT) was diagnosed by ultrasonography at postoperative day 3 and 14. Computed tomography to detect pulmonary thromboembolism was performed to all patients who had proximal DVTs. The χ2 test with Bonferroni correction was used to compare variables of the incidence of DVT between each group. The intention-to-treat analysis was performed for statistical analysis in each group. The EDO30 mg group and EDOmix group were regarded as one group in the assessment at the postoperative day 3, and named as the EDO30mg+mix group.
Result
There was no fetal bleeding, bleeding in a critical organ, or bleeding leading to reoperation. One patient in the FPX group dropped out due to discontinuation of administration due to proximal DVT at postoperative day 3 and switch to fibrinolytic therapy therapy. One patient in the EDO15mg group dropped out due to stop of administration because of subconjunctival hemorrhage at postoperative day 9. All the patients took the ultrasonography at postoperative day 3. The incidence of DVT was 13.8% (11/80) in the FPX group, 20.0% (16/80) in the EDO15mg group, and 15.0% (24/160) in the EDO30mg+mix group. At the postoperative day 14, except for dropouts, the incidence of DVT was 5.1% (4/79) in the FPX group, 19.0% (15/79) in the EDO15mg group, 8.8% (7/80) in the EDO30mg group, 13.8% (11/80) in the EDOmix group. One proximal DVT was detected in the FPX group at the postoperative day 3, and in other three groups at the postoperative day 14, of which, asymptomatic PE was detected in one patient in each FPX group and EDO30mg group. There was no significance between other each group in the intention-to-treat analysis. The incidence of DVT in the FPX group had a tendency to be lower than that of DVT in the EDO15mg group (p = 0.06).
Discussion and conclusions
The results suggest that fondaparinux and edoxaban have an equal effect to prevent DVT for Japanese patients undergoing elective cemented THR. From the point of view of the cost-effectiveness and safety, edoxaban may be worth considering as an alternative.
