Should stroke patients use Deep Vein Thrombosis (DVT) prophylaxis with heparin?

DVT Prophylaxis with Heparin in Stroke Patients

Stroke patients should receive DVT prophylaxis, but the approach differs critically by stroke type: for ischemic stroke, use intermittent pneumatic compression (IPC) as first-line with selective use of prophylactic-dose heparin based on individualized bleeding risk assessment; for hemorrhagic stroke, use IPC initially and consider adding prophylactic heparin only after 48 hours (ideally 2-4 days) once hematoma stability is confirmed on repeat imaging. 1, 2

Ischemic Stroke: Prioritize Mechanical Over Pharmacological Prophylaxis

Primary Recommendation: Intermittent Pneumatic Compression

• IPC should be the first-line DVT prophylaxis for immobile ischemic stroke patients, applied within 24 hours of admission and continued until independent mobility is regained, discharge, or 30 days (whichever comes first). 1, 3
• The CLOTS 3 trial (n=2,867) demonstrated IPC reduced DVT from 14.0% to 9.6% (adjusted OR 0.65,95% CI 0.51-0.84) and improved 6-month survival (hazard ratio 0.86,95% CI 0.73-0.99). 1
• IPC carries minimal risk, with only a small increase in skin breaks (3.1% vs 1.4%). 1

Pharmacological Prophylaxis: Use Selectively with Caution

• Prophylactic-dose heparin (UFH or LMWH) should be used only when VTE risk clearly outweighs bleeding risk, as the evidence shows no mortality benefit and increased bleeding complications. 1
• The International Stroke Trial (n=14,578) found no mortality benefit from prophylactic heparin in ischemic stroke, with increased hemorrhagic stroke and extracranial bleeding (absolute increase of 5 events per 1,000 patients). 1
• Meta-analyses show heparin reduces pulmonary embolism (absolute decrease 3-4 per 1,000) but increases major bleeding (absolute increase 1-6 per 1,000), with no effect on mortality or symptomatic DVT. 1, 4

When to Consider Heparin in Ischemic Stroke

Use prophylactic heparin if the patient has multiple high-risk VTE factors AND low bleeding risk:

High VTE Risk Factors: 1

• Age >75 years
• Complete immobility (unable to ambulate)
• Prior VTE history
• Active cancer
• Severe heart failure
• Chronic kidney disease
• Obesity
• Prolonged hospitalization expected

Contraindications/High Bleeding Risk: 1

• Recent intracranial hemorrhage or prior hemorrhagic stroke
• Active bleeding or bleeding disorder
• Severe thrombocytopenia
• Severe uncontrolled hypertension
• Recent major surgery
• Peptic ulcer disease
• Severe liver disease
• Concomitant antiplatelet therapy (increases bleeding risk)

Dosing and Timing for Ischemic Stroke

• Prophylactic-dose UFH: 5,000 units subcutaneously 2-3 times daily 1, 2
• Prophylactic-dose LMWH: enoxaparin 40 mg subcutaneously once daily (or 3,000-6,000 IU/day of other LMWHs) 1, 2
• LMWH is preferred over UFH due to greater reduction in DVT (7 fewer symptomatic DVTs per 1,000), fewer pulmonary emboli (8 fewer per 1,000), and convenience of once-daily dosing. 1
• Do NOT use heparin within 24 hours after thrombolytic therapy administration. 1
• Initiate within 48 hours of stroke onset if used, continue throughout hospitalization or until mobility is regained. 1

What NOT to Use

• Graduated compression stockings (GCS) should NOT be used - they provide no benefit and increase skin complications. 1, 3

Hemorrhagic Stroke (Intracerebral Hemorrhage): Delayed Pharmacological Approach

Initial Management: Mechanical Prophylaxis Only

• Start IPC on day of admission for all immobile ICH patients, as it carries no bleeding risk. 1, 2
• Continue IPC until independent mobility, discharge, or 30 days. 1

Timing of Heparin Initiation

• Prophylactic-dose heparin (LMWH or UFH) may be considered starting 48 hours to 4 days post-ICH onset, but only after: 2, 5, 6

  • Repeat brain imaging confirms hematoma stability (no expansion)
  • Careful assessment shows VTE risk exceeds bleeding risk
  • Documentation of cessation of active bleeding

• The optimal timing is 2-4 days post-onset based on safety data, though some guidelines suggest waiting until day 4. 2, 5

Evidence for Safety in ICH

• A prospective randomized trial (n=75) showed enoxaparin 40 mg daily started after 48 hours caused no hematoma enlargement or systemic bleeding complications compared to compression stockings alone. 6
• The evidence quality for hemorrhagic stroke is lower than for ischemic stroke, requiring more cautious decision-making. 2

Dosing for Hemorrhagic Stroke

• Same prophylactic doses as ischemic stroke: UFH 5,000 units 2-3 times daily or LMWH (enoxaparin 40 mg once daily). 2, 6
• LMWH is generally preferred over UFH except in patients with renal failure. 2

Duration of Prophylaxis for All Stroke Types

• Continue throughout the entire hospital stay (including rehabilitation facilities) or until the patient regains independent mobility, whichever comes first. 1
• For patients remaining immobile beyond 30 days, ongoing prophylaxis is recommended. 2
• For patients with mild impairments discharged directly home, DVT prophylaxis may not be needed. 1

Critical Pitfalls to Avoid

• Do not use therapeutic-dose anticoagulation for DVT prophylaxis - this significantly increases bleeding without additional benefit. 1
• Do not delay IPC while debating pharmacological prophylaxis - IPC should start immediately in all immobile patients. 1
• Do not use compression stockings - they are ineffective and harmful. 1, 3
• Do not start heparin in ICH without repeat imaging confirming hematoma stability. 2
• Reassess bleeding and VTE risk daily as clinical status changes. 1

Adjunctive Measures for All Patients

• Early mobilization should be encouraged as soon as medically safe. 2, 5
• Maintain adequate hydration to reduce VTE risk. 2, 5
• Aspirin 160-325 mg daily should be given to ischemic stroke patients (not for DVT prophylaxis per se, but for secondary stroke prevention), which may provide modest DVT protection. 1, 5