Thrombolysis for Acute Ischemic Stroke and Pulmonary Embolism
For acute ischemic stroke, intravenous recombinant tissue plasminogen activator (IV r-tPA) is strongly recommended if treatment can be initiated within 3 hours of symptom onset, with a more cautious recommendation for the 3-4.5 hour window, while thrombolysis is not recommended beyond 4.5 hours. 1
Acute Ischemic Stroke Thrombolysis
Timing and Eligibility
- Within 3 hours: IV r-tPA strongly recommended (Grade 1A) 1
- 3-4.5 hours: IV r-tPA suggested but with lower evidence (Grade 2C) 1
- Beyond 4.5 hours: IV r-tPA not recommended (Grade 1B) 1
Dosing and Administration
- Dose: 0.9 mg/kg (maximum 90 mg) over 60 minutes
- Initial 10% given as bolus over 1 minute
- Blood glucose check required before administration
- Blood pressure must be below 185/110 mmHg before initiating thrombolysis 2
Key Exclusion Criteria
- Symptom onset >4.5 hours or unknown onset time
- Another stroke or serious head injury within preceding 3 months
- Major surgery within prior 14 days
- History of intracranial hemorrhage
- Gastrointestinal or genitourinary hemorrhage within previous 21 days 2
Alternative Approaches
- Intraarterial (IA) r-tPA: For patients ineligible for IV r-tPA with proximal cerebral artery occlusions, IA r-tPA may be considered if initiated within 6 hours of symptom onset (Grade 2C) 1
- Mechanical thrombectomy: Generally not recommended (Grade 2C), though carefully selected patients may choose this intervention 1
Post-Thrombolysis Monitoring
- Neurological evaluations every 15 minutes for first 2 hours
- Every 30 minutes for next 6 hours
- Every hour thereafter
- Monitor closely for symptomatic intracranial hemorrhage, especially within first 12 hours 2
Antiplatelet Therapy After Stroke/TIA
- Early aspirin therapy (160-325 mg within 48 hours) recommended for acute ischemic stroke or TIA (Grade 1A) 1, 2
- Long-term antiplatelet therapy should be initiated for secondary prevention in noncardioembolic stroke/TIA 2
Venous Thromboembolism Prophylaxis in Stroke Patients
- For patients with restricted mobility:
Important Considerations and Pitfalls
Time Window Limitations
The most common reason patients are ineligible for thrombolysis is delayed presentation beyond the time window 3. Only about 15% of stroke patients arrive within the 3-hour window, making public education about stroke symptoms and rapid response critical.
Hemorrhage Risk
Thrombolysis significantly increases the risk of symptomatic intracerebral hemorrhage, particularly when administered beyond 3 hours after symptom onset 4, 5. Studies have shown that treatment between 3-5 hours after onset showed no significant benefit on functional outcomes but increased hemorrhage risk 4, 5.
Mild Symptoms or Rapid Improvement
Patients with mild neurological impairment or rapidly improving symptoms are often excluded from thrombolysis, though this remains a clinical judgment call 3.
Concomitant Pulmonary Embolism and Stroke
In rare cases of concomitant acute stroke and pulmonary embolism, IV thrombolysis has been used successfully, followed by anticoagulation after 24 hours 6. However, this represents a challenging clinical scenario requiring careful consideration of risks and benefits.
By following these evidence-based guidelines for thrombolysis in acute ischemic stroke, clinicians can optimize patient outcomes while minimizing risks of treatment complications.