Should a ventilated patient be on a heparin (unfractionated heparin) drip for venous thromboembolism prophylaxis?

VTE Prophylaxis in Ventilated Patients

Ventilated patients should receive pharmacologic VTE prophylaxis with subcutaneous low-dose unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH), not a continuous heparin drip, unless bleeding risk outweighs the benefits. 1

Route of Administration: Subcutaneous, Not Intravenous Drip

• Subcutaneous administration is the standard route for VTE prophylaxis in critically ill and ventilated patients 1
• Continuous intravenous heparin drips are reserved for therapeutic anticoagulation (treatment of existing VTE), not prophylaxis 2, 3
• Low-dose subcutaneous UFH (5,000 IU three times daily) or LMWH (e.g., enoxaparin 40 mg once daily) are the recommended prophylactic regimens 1

Specific Recommendations for Critically Ill/Ventilated Patients

• LMWH is preferred over UFH for VTE prophylaxis in critically ill patients when no contraindications exist 1
• For patients with severe renal impairment (creatinine clearance <30 mL/min), UFH is preferred over LMWH due to renal metabolism concerns 1
• Prophylaxis should be initiated as soon as the patient is hemodynamically stable 4

Duration and Timing

• Continue prophylaxis throughout the period of immobilization or acute hospital stay 1, 5
• For patients remaining immobile beyond 30 days, ongoing prophylaxis is specifically recommended 5
• Do not extend prophylaxis beyond the period of immobilization unless specific high-risk factors persist 1

Combination Approach for High-Risk Patients

• Add mechanical prophylaxis (intermittent pneumatic compression) to pharmacologic prophylaxis whenever possible in critically ill patients 1
• Graduated compression stockings are not recommended as sole prophylaxis 1

When to Avoid Pharmacologic Prophylaxis

• Active bleeding is an absolute contraindication 4
• Severe thrombocytopenia contraindicates heparin use 4
• Recent intracranial hemorrhage requires mechanical prophylaxis only 4
• When bleeding risk is high, use mechanical prophylaxis (intermittent pneumatic compression) until bleeding risk decreases, then switch to pharmacologic prophylaxis 1

Common Pitfalls to Avoid

• Do not use continuous IV heparin drips for prophylaxis—this is therapeutic dosing, not prophylactic, and increases bleeding risk unnecessarily 3
• Do not withhold prophylaxis in all ventilated patients universally—individualized risk assessment for both VTE and bleeding is essential 1
• Do not use graduated compression stockings alone—they are ineffective as monotherapy 1
• Do not forget to reassess bleeding risk daily in critically ill patients, as this can change rapidly 1

Risk Assessment Framework

VTE risk factors in ventilated patients include: 1

• Immobilization (primary factor in ventilated patients)
• Sepsis or septic shock
• Advanced age (>75 years)
• Active cancer
• History of prior VTE
• Central venous catheters
• Obesity

Bleeding risk factors include: 1

• Active bleeding or recent hemorrhage
• Severe thrombocytopenia (platelets <50,000)
• Coagulopathy
• Recent neurosurgery or intracranial hemorrhage
• Severe liver disease