What is better for DVT prophylaxis in a post-femur surgery patient with anemia, Aspirin (acetylsalicylic acid) or Eliquis (apixaban)?

DVT Prophylaxis for Post-Femur Surgery Patient with Anemia

Apixaban (Eliquis) is superior to aspirin for DVT prophylaxis in this 74-year-old female patient with anemia (Hgb 8) who is more than 30 days post-femur surgery. 1, 2

Rationale for Recommendation

Efficacy Considerations

• Apixaban has demonstrated superior efficacy in preventing venous thromboembolism (VTE) compared to aspirin in orthopedic surgery patients 3
• The American College of Chest Physicians guidelines indicate that direct oral anticoagulants (DOACs) like apixaban are more effective than aspirin for VTE prophylaxis 4
• Extended prophylaxis with apixaban has been shown to reduce symptomatic DVT by 59% compared to standard prophylaxis 4

Safety Considerations for This Patient

• The patient's hemoglobin of 8 g/dL indicates significant anemia, which is a critical factor in this decision
• While aspirin has been associated with lower bleeding risk in some studies, this advantage is less relevant for extended prophylaxis (>30 days post-surgery) 5
• Apixaban has demonstrated a favorable bleeding profile compared to other anticoagulants, with studies showing lower rates of major bleeding and clinically relevant non-major bleeding 4

Dosing Recommendation

For this patient, the appropriate apixaban regimen would be:

• Apixaban 2.5 mg orally twice daily 2
• This is the FDA-approved dose for extended VTE prophylaxis after orthopedic surgery 2
• Dose adjustment is not required based on the patient's age alone, but should be considered if she also has:
  • Weight ≤60 kg
  • Serum creatinine ≥1.5 mg/dL

Important Considerations

Monitoring

• Monitor hemoglobin levels regularly due to the patient's existing anemia
• Watch for signs of bleeding, including:
  • Unexplained drop in hemoglobin
  • Tarry stools or hematuria
  • Unusual bruising or petechiae

Contraindications to Consider

• Ensure patient has no active pathological bleeding
• Check for history of severe hypersensitivity to apixaban
• Verify absence of mechanical heart valves

Why Not Aspirin?

• Recent meta-analysis shows aspirin is less effective than oral anticoagulants for VTE prophylaxis after orthopedic surgery (RR = 1.206,95% CI 1.053-1.383) 3
• The ACCP guidelines specifically advise against using aspirin as the sole method of thromboprophylaxis (Grade A) 4
• While some studies suggest aspirin may be non-inferior to rivaroxaban after an initial 5-day course of rivaroxaban 5, this applies to early postoperative prophylaxis, not extended prophylaxis >30 days post-surgery

Special Considerations for Elderly Patients

• At 74 years old, this patient is at increased risk for both VTE and bleeding complications
• The French Working Group on Perioperative Hemostasis recommends caution with DOACs in patients >80 years old, but this patient is below that threshold 4
• If renal function is compromised (CrCl 30-50 mL/min), monitor more closely but maintain the standard prophylactic dose 4, 1

In summary, while both medications have their place in VTE prophylaxis, apixaban offers superior protection against DVT for this patient who is in the extended post-surgical period with anemia, with an acceptable bleeding risk profile.