Do we load patients (pts) with aspirin (acetylsalicylic acid) in acute ischemic stroke or transient ischemic attack (TIA)?

Aspirin Loading in Acute Ischemic Stroke and TIA

Yes, patients with acute ischemic stroke or TIA should receive an early loading dose of aspirin at 160-325 mg within 48 hours of symptom onset after excluding intracranial hemorrhage. 1

Initial Management Algorithm

1. Confirm diagnosis and exclude hemorrhage:

   • Perform neuroimaging to rule out intracranial hemorrhage before administering aspirin 1
   • Perform dysphagia screening to ensure safe oral administration 1

2. Aspirin loading dose administration:

   • Timing: Administer within 48 hours of symptom onset 1
   • Dose: 160-325 mg as a one-time loading dose 1
   • Route: Oral preferred; enteral tube (80 mg) or rectal suppository (325 mg) for dysphagic patients 1

3. Special considerations:

   • For patients who received thrombolytic therapy (r-tPA), delay aspirin until after the 24-hour post-thrombolysis scan has excluded hemorrhage 1
   • For patients already on aspirin prior to the event, consider clopidogrel as an alternative 1

Evidence Supporting Aspirin Loading

The recommendation for early aspirin therapy is supported by high-quality evidence (Grade 1A) from multiple guidelines 1. The American College of Chest Physicians specifically recommends early aspirin therapy at a dose of 160-325 mg over no aspirin therapy in patients with acute ischemic stroke or TIA 1.

Research shows that higher loading doses of aspirin (160-325 mg) are associated with:

• Better clinical outcomes at discharge compared to lower doses 2
• Reduced risk of early recurrent ischemic stroke 1
• Reduced risk of death and dependency in the long term 1

Dual Antiplatelet Considerations

For patients with minor ischemic stroke or high-risk TIA:

• Consider adding clopidogrel loading (300-600 mg) along with aspirin loading 3
• This combination provides rapid platelet inhibition within 12-24 hours 3
• Continue with clopidogrel 75 mg daily plus aspirin 81 mg daily for 21 days, then transition to single antiplatelet therapy 3

Maintenance Therapy After Loading

• Continue aspirin at 81-325 mg daily indefinitely or until an alternative antithrombotic regimen is started 1
• For long-term stroke prevention in non-cardioembolic stroke or TIA, guidelines suggest:
  • Aspirin (75-100 mg daily) 1
  • Clopidogrel (75 mg daily) or aspirin/extended-release dipyridamole may be preferred over aspirin alone for long-term therapy 1

Safety Considerations

• Monitor for bleeding complications, especially with higher loading doses 2
• The LOAD pilot study demonstrated that antiplatelet loading appears safe when administered up to 36 hours after stroke/TIA onset 4
• Higher doses (160-325 mg) may cause more minor bleeding events but have better clinical outcomes 2

Common Pitfalls to Avoid

• Delaying aspirin administration: Early administration (within 48 hours) is critical for reducing recurrent stroke risk 1
• Administering aspirin before ruling out hemorrhage: Always confirm absence of intracranial hemorrhage first 1
• Administering aspirin too soon after thrombolysis: Wait for 24-hour post-thrombolysis scan to exclude hemorrhage 1
• Using inadequate loading dose: Doses below 160 mg may provide suboptimal benefit in the acute setting 2