Can heparin be used for Deep Vein Thrombosis (DVT) prophylaxis in elderly patients?

Heparin for DVT Prophylaxis in Elderly Patients

Low molecular weight heparin (LMWH) is superior to unfractionated heparin (UFH) for DVT prophylaxis in most elderly patients, but UFH is preferred in those with severe renal impairment (creatinine clearance <30 mL/min). 1

Risk Assessment and Indications

Elderly patients (≥65 years) are at increased risk for venous thromboembolism (VTE) due to:

• Age itself is an independent risk factor (2 points on the TESS score) 1
• Reduced mobility
• Higher prevalence of comorbidities
• Hospitalization for acute medical conditions

Specific Indications for Prophylaxis:

• Hospitalized elderly patients with active malignancy and acute medical illness or reduced mobility 1
• Elderly patients undergoing major surgery, especially orthopedic or abdominal procedures
• Trauma patients (particularly those with ISS >10) 1

Choice of Agent

For Most Elderly Patients:

• LMWH is preferred over UFH due to:
  • Lower incidence of DVT (1.7% vs 6.3%, RR = 0.26) 2
  • Fewer bleeding complications 1
  • Lower rates of pulmonary embolism (PE) 1
  • Reduced mortality (P < 0.001) 1
  • Lower rates of myocardial infarction, cardiac arrest, and severe sepsis 1

For Elderly Patients with Renal Impairment:

• UFH is preferred when creatinine clearance <30 mL/min 1, 3
• LMWH can accumulate in patients with severe renal insufficiency, increasing bleeding risk 1

Dosing Recommendations

LMWH (for patients with normal renal function):

• Enoxaparin: 40 mg subcutaneously once daily 1
• Dalteparin: 5,000 U subcutaneously once daily 1
• For elderly patients >65 years: Initial dose of enoxaparin should be 30 mg every 12 hours 1

UFH (especially for patients with renal impairment):

• 5,000 U subcutaneously every 8 hours 1, 3
• Three-times-daily dosing is more effective than twice-daily dosing 3

Special Considerations for Elderly Patients

Monitoring:

• For patients receiving UFH: Consider monitoring platelet counts every 2-3 days from day 4 to day 14 to screen for heparin-induced thrombocytopenia (HIT) 1
• For patients receiving LMWH with renal impairment: Consider monitoring anti-Xa levels 1

Contraindications:

• Active major bleeding
• Severe thrombocytopenia
• History of HIT
• Known sensitivity to heparin or its components 1

Precautions:

• Uncontrolled hypertension
• Liver failure with elevated INR
• Concurrent use of antiplatelet drugs 1

Duration of Prophylaxis

• Continue for the duration of hospitalization or until fully mobile
• For high-risk surgical patients, continue for at least 10 days postoperatively 3

Combination with Mechanical Prophylaxis

• For highest-risk elderly patients, consider combining pharmacological prophylaxis with intermittent pneumatic compression devices 1
• Use mechanical methods alone when pharmacological prophylaxis is contraindicated 1

Conclusion

When administering DVT prophylaxis to elderly patients, LMWH is generally superior to UFH in terms of efficacy and safety. However, in patients with severe renal impairment (CrCl <30 mL/min), UFH 5,000 U every 8 hours is the preferred agent due to its hepatic metabolism and lower risk of bioaccumulation.