What is the recommended prophylaxis for patients at risk of developing Deep Vein Thrombosis (DVT)?

DVT Prophylaxis Recommendations

Low molecular weight heparin (LMWH) is the preferred pharmacological agent for DVT prophylaxis in most hospitalized patients at risk for venous thromboembolism, with specific regimens determined by risk stratification. 1

Risk Assessment

The first step in DVT prophylaxis is proper risk assessment using validated tools:

• Caprini Risk Assessment Model categorizes thrombosis risk as:

  • Very low (0 points; 0.5%)
  • Low (1-2 points; 1.5%)
  • Moderate (3-4 points; 3%)
  • High (≥5 points; 6%) 2

• Patient-specific risk factors that increase DVT risk include:

  • Age >40 years (especially >60 years)
  • Prior history of VTE
  • Cancer
  • Obesity
  • Pregnancy/estrogen therapy
  • Immobility 2

Prophylaxis Recommendations by Risk Category

Low Risk Patients

• Early ambulation alone is sufficient 2
• No pharmacological prophylaxis needed

Moderate Risk Patients

• Unfractionated heparin (UFH) 5000 units subcutaneously every 12 hours 2
• OR LMWH (preferred over UFH) 1

High Risk Patients

• UFH 5000 units subcutaneously every 8 hours 2
• OR LMWH (preferred option) 1

Very High Risk Patients

• Enoxaparin 40 mg subcutaneously daily (reduce to 30 mg if CrCl <30 ml/min) 2
• PLUS intermittent pneumatic compression devices (IPC) 2
• For patients with high bleeding risk, use mechanical prophylaxis (IPC) alone until bleeding risk decreases 2

Specific LMWH Regimens (Preferred Options)

• Enoxaparin: 40 mg subcutaneously once daily 1
• Dalteparin: 5000 IU subcutaneously once daily 1
• Fondaparinux: 2.5 mg subcutaneously once daily 1

Special Populations

Surgical Patients

• Major orthopedic surgery: Multiple options including LMWH, fondaparinux, dabigatran, apixaban, rivaroxaban, low-dose UFH, adjusted-dose vitamin K, or aspirin 2
• Hip/knee replacement: Rivaroxaban 10 mg daily is FDA-approved for VTE prophylaxis 3
• Duration: Minimum 10-14 days, with consideration of up to 35 days for high-risk patients 2

Cancer Patients

• Should receive 4 weeks of LMWH 2
• Higher intensity prophylaxis with UFH 5000 U three times daily may be beneficial 1

Trauma Patients

• Both mechanical and pharmacological prophylaxis unless contraindicated 2
• Inferior vena cava filters not routinely recommended for primary prevention 2

Acutely Ill Medical Patients

• Rivaroxaban 10 mg daily for 31-39 days total (in-hospital and post-discharge) for those not at high bleeding risk 3

Mechanical Prophylaxis

• Intermittent pneumatic compression (IPC): Recommended for 18 hours daily in addition to anticoagulant therapy 2
• Should not be used as monotherapy unless pharmacological methods are contraindicated due to active bleeding or high bleeding risk 1
• Particularly useful for patients in whom heparin prophylaxis should be avoided (e.g., neurosurgery) 4

Duration of Prophylaxis

• Continue throughout hospitalization until the patient is fully mobile or discharged 1
• Extended prophylaxis (28-35 days) recommended for high-risk patients undergoing major abdominal or pelvic surgery 1

Common Pitfalls to Avoid

• Inadequate risk assessment leading to insufficient prophylaxis 1
• Inappropriate prophylaxis duration - not extending for high-risk patients or continuing unnecessarily in low-risk patients 1
• Overlooking contraindications such as active bleeding or severe thrombocytopenia (platelets <25×10⁹/L) 1
• Underutilization of prophylaxis - only 58.5% of at-risk surgical patients and 39.5% of at-risk medical patients receive recommended prophylaxis 1

Contraindications to Pharmacological Prophylaxis

• Active pathological bleeding 3
• Severe thrombocytopenia (platelets <25×10⁹/L) 1
• Recent intracranial hemorrhage 1
• Heparin-induced thrombocytopenia 1

DVT prophylaxis is essential for reducing morbidity and mortality associated with venous thromboembolism. Using a risk-stratified approach with LMWH as the preferred pharmacological agent provides the best balance of efficacy and safety for most patients.