What dose of Xaralto (rivaroxaban) is recommended for DVT prophylaxis in a patient with a high risk of thromboembolic events after femur nailing surgery?

Rivaroxaban Dosing for DVT Prophylaxis After Femur Nailing Surgery

Recommended Dose

For DVT prophylaxis after femur nailing surgery in a high-risk patient, use rivaroxaban 10 mg orally once daily for 35 days, starting 6-8 hours post-operatively once hemostasis is assured. 1

Dosing Algorithm

Initial Dose Timing

• Start rivaroxaban 6-8 hours after surgery once surgical hemostasis is confirmed 2, 3
• Do not initiate if an epidural catheter remains in place—wait until after catheter removal 4
• For patients with high bleeding risk from the surgical procedure, consider delaying initiation to 24 hours post-operatively 4

Standard Prophylactic Regimen

• 10 mg orally once daily is the FDA-approved dose for major orthopedic surgery prophylaxis 2
• Duration: 35 days for hip fracture surgery, which is the appropriate comparator for femur nailing given similar thrombotic risk 2, 1
• This mirrors the dosing validated in the RECORD trials for hip arthroplasty 2

Dose Adjustments for Renal Function

• CrCl 30-50 mL/min: No dose adjustment needed for prophylaxis 2
• CrCl 15-30 mL/min: Use with caution; consider alternative anticoagulation 2
• CrCl <15 mL/min: Contraindicated 4
• Monitor renal function post-operatively as surgical trauma may affect kidney function 2, 1

Special Considerations for High-Risk Patients

• P-glycoprotein inhibitors (e.g., verapamil, amiodarone): Use standard 10 mg dose but monitor closely 2
• Potent CYP3A4 and P-gp inhibitors (ketoconazole, ritonavir): Contraindicated 1
• Age ≥75 years: No dose adjustment required for prophylaxis 2

Bridging Strategy (If Needed)

• No preoperative heparin bridging is required except in very high thrombotic risk scenarios 2
• If VTE prophylaxis is needed before rivaroxaban initiation, use prophylactic-dose LMWH or fondaparinux starting 6-12 hours post-operatively 2, 4
• When transitioning from prophylactic LMWH to rivaroxaban, administer the first rivaroxaban dose 12 hours after the last LMWH dose 2, 4

Critical Pitfalls to Avoid

• Never use the treatment dose (15 mg twice daily) for prophylaxis—this significantly increases bleeding risk without additional benefit 4, 5
• Do not start rivaroxaban with an epidural catheter in place—this risks spinal/epidural hematoma 2, 4
• Avoid overlapping with therapeutic-dose anticoagulation—ensure proper timing when transitioning from LMWH 2
• Do not use in severe hepatic disease with coagulopathy or severe renal insufficiency (CrCl <30 mL/min) 2

Monitoring Requirements

• No routine coagulation monitoring required, unlike warfarin 1, 6
• Monitor renal function post-operatively, particularly if the surgical procedure or patient condition could affect kidney function 2, 1
• Baseline assessment should include creatinine clearance calculation using Cockcroft-Gault formula 2

Evidence Supporting This Approach

The RECORD trials demonstrated that rivaroxaban 10 mg once daily for 35 days after hip arthroplasty reduced DVT, PE, or death compared to enoxaparin without increased bleeding rates 2. Extended duration rivaroxaban (31-39 days) was more effective than shorter-duration enoxaparin (10-14 days) without increased bleeding complications 2. The American College of Chest Physicians guidelines support this 35-day regimen for hip fracture surgery, which carries similar thrombotic risk to femur nailing 1. Pooled analysis from phase II studies confirmed that rivaroxaban 10 mg total daily dose (5 mg twice daily) provided the most favorable efficacy-safety balance 6.