What is the recommended Deep Vein Thrombosis (DVT) prophylaxis for patients after hip fracture surgery?

DVT Prophylaxis After Hip Fracture Surgery

Low molecular weight heparin (LMWH) is the preferred pharmacological agent for DVT prophylaxis in hip fracture patients, with enoxaparin 30 mg subcutaneously twice daily starting 12-24 hours after surgery and continuing for 10-14 days, with extension up to 35 days recommended for optimal outcomes. 1

Pharmacological Prophylaxis Options

Primary Recommendation

• LMWH (First-line):
  • Enoxaparin 30 mg subcutaneously twice daily starting 12-24 hours after surgery 1
  • Continue for 10-14 days routinely, with extension up to 35 days for optimal outcomes 1
  • LMWH has demonstrated lower incidence of DVT and PE compared to UFH, with fewer bleeding complications 1

Alternative Options

1. Fondaparinux:

   • Dose: 2.5 mg subcutaneously once daily 2
   • Initial dose: No earlier than 6-8 hours after surgery (earlier administration increases major bleeding risk) 2
   • Duration: 5-9 days standard; extended prophylaxis up to 24 additional days (total 32 days) recommended for hip fracture surgery 2, 3
   • Contraindicated in severe renal impairment (CrCl <30 mL/min) 1

2. Direct Oral Anticoagulants (DOACs):

   • The American College of Chest Physicians recommends DOACs over aspirin 1
   • Rivaroxaban 10 mg once daily starting 6-10 hours after surgery 1

3. Unfractionated Heparin (UFH):

   • 5000 U subcutaneously every 8 hours 1
   • Primary use when LMWH is contraindicated or in patients with severe renal insufficiency 1

Timing and Duration Considerations

• Timing: Administer first dose 12-24 hours after surgery for LMWH; 6-8 hours after surgery for fondaparinux 4, 2
• Duration:
  • Standard: 10-14 days for LMWH; 5-9 days for fondaparinux 1, 2
  • Extended prophylaxis: Up to 35 days for LMWH or 32 days (5-9 days standard + 24 days extended) for fondaparinux 1, 2
  • Extended prophylaxis (≥28 days) is associated with a 67% lower odds of death compared to short-duration prophylaxis 1

Special Patient Considerations

1. Renal Impairment:

   • Severe (CrCl <30 mL/min): Avoid fondaparinux; use UFH 5000 U every 8 hours 1
   • Moderate (CrCl 30-50 mL/min): Use LMWH with caution and consider dose adjustment 1

2. Elderly Patients:

   • For patients >65 years: Enoxaparin 30 mg every 12 hours 1
   • For patients >75 years: Use fondaparinux with caution 1

3. Weight Considerations:

   • Patients <50 kg: Use fondaparinux with caution 1
   • Morbidly obese patients: Consider institutional LMWH dosing algorithm 1

Mechanical Prophylaxis

• Thromboembolism stockings or intermittent compression devices should be employed intraoperatively 4
• Use as adjunct to pharmacological prophylaxis in all patients 4, 1
• Use as primary prophylaxis when pharmacological methods are contraindicated due to active bleeding, coagulopathy, or hemodynamic instability 1

Additional Preventive Measures

• Ensure patient remains warm and well-hydrated during surgery 4
• Expedited surgery and early mobilization may further reduce DVT risk 4
• Regional anesthesia may provide additional DVT risk reduction 4

Monitoring

• No routine monitoring is required for LMWH prophylaxis 1
• Consider anti-Xa level monitoring for patients with renal dysfunction 1

Clinical Efficacy Data

• Studies show that DVT occurs in 37% of hip fracture patients without prophylaxis, with clinical symptoms in only 1-3% 4
• Extended prophylaxis with fondaparinux after hip fracture has demonstrated further reduction in VTE events without increasing bleeding risk 3
• LMWH has been shown to be significantly less hemorrhagic than standard unfractionated heparin 5

Despite published guidelines, compliance with recommended prophylaxis varies widely, with one study showing only 45% of hip fracture patients receiving prophylaxis in accordance with ACCP recommendations 4. This highlights the importance of implementing standardized protocols for DVT prophylaxis in hip fracture patients.