When to restart aspirin (acetylsalicylic acid) after a subdural hematoma?

From the Guidelines

Aspirin should be restarted 7 to 10 days after the onset of a subdural hematoma in patients with a high risk of thromboembolism, as indicated by the American Heart Association/American Stroke Association guidelines 1.

Considerations for Restarting Aspirin

When considering restarting aspirin after a subdural hematoma, it is essential to weigh the risks of recurrent bleeding against the benefits of preventing thromboembolic events. The decision to restart aspirin should be individualized based on the patient's specific risk factors, including the original indication for aspirin therapy, such as coronary artery disease, stroke prevention, or peripheral vascular disease.

• The patient's overall neurological function and the presence of any comorbidities that may increase the risk of bleeding or thromboembolism should be taken into account.
• The size and location of the subdural hematoma, as well as the presence of any other intracranial abnormalities, should also be considered.
• Regular neurological monitoring is essential after restarting aspirin, and patients should be educated about warning signs of recurrent bleeding that would require immediate medical attention.

Timing of Aspirin Restart

The timing of aspirin restart depends on the individual patient's risk factors and the specific clinical scenario.

• For patients with a high risk of thromboembolism, aspirin may be restarted as early as 7 to 10 days after the onset of the subdural hematoma, as recommended by the American Heart Association/American Stroke Association guidelines 1.
• For patients with a lower risk of thromboembolism, aspirin may be restarted later, typically after 4-6 weeks, and only after confirmation of hematoma resolution with follow-up imaging.
• The lowest effective dose of aspirin should be used, often beginning with 81mg daily.

Multidisciplinary Approach

The decision to restart aspirin after a subdural hematoma should involve a multidisciplinary discussion between neurosurgery, neurology, and cardiology.

• This approach ensures that all relevant factors are considered, and the patient receives comprehensive care.
• The patient's original indication for aspirin therapy, as well as their current risk factors and overall health status, should be taken into account when making the decision to restart aspirin.
• Recent guidelines, such as the 2024 ESC guidelines for the management of chronic coronary syndromes, recommend lifelong low-dose aspirin in patients undergoing CABG, and aspirin should be continued until the day of CABG and restarted as soon as there is no concern over bleeding 1.

From the Research

Restarting Aspirin after Subdural Hematoma

• The optimal timing for restarting aspirin after a subdural hematoma is not well-established, but studies suggest that the decision should be made on a case-by-case basis 2, 3, 4.
• A study published in World Neurosurgery found that the median restart time for antiplatelet therapy (APT) was 2-4 weeks after trauma, depending on the clinical indication 2.
• Another study published in the Journal of Neurotrauma found that delaying surgery after cessation of antiplatelet drug did not affect the risk of bleed recurrence, and early surgery and early antithrombotic recommencement should be considered in patients at high risk of thromboembolic events 3.
• A systematic review published in Neurology found that anticoagulant medication was associated with increased rebleeding risk in older adults with chronic subdural hematoma, but antiplatelet medication was not associated with increased risk of rebleeding 4.
• A meta-analysis published in the Journal of Stroke and Cerebrovascular Diseases found that aspirin use increases the relative risk of subdural hematoma, but the absolute increased rate associated with aspirin therapy is very low for most people 5.

Considerations for Restarting Aspirin

• Patients with coronary artery disease or atrial fibrillation may require earlier reinitiation of antiplatelet or anticoagulant therapy due to a higher risk of thrombotic/thromboembolic events 2, 3.
• The risk of rebleeding and thromboembolic events should be carefully weighed when deciding when to restart aspirin after a subdural hematoma 2, 3, 4.
• Close follow-up is recommended for patients who require reinitiation of antiplatelet or anticoagulant therapy after a subdural hematoma 2, 3.