Risk of Hematoma From Aspirin or Clopidogrel Owing to Lumbar Puncture.

Neurologists are worried about bleeding and complications from lumbar punctures in patients who use antiplatelet agents, such as aspirin and clopidogrel. We evaluated the bleeding risks of performing lumbar punctures in patients who are using or have recently used antiplatelet agents by retrospective review of lumbar punctures performed at the Johns Hopkins Hospital between 2004 and 2018 in patients who were actively using or recently used aspirin or clopidogrel, or both. Patients were stratified into time groups based on when the lumbar puncture was done relative to the time the antiplatelet drug was discontinued: <1 week, 1-4 weeks, >4 weeks. We recorded red blood cell counts for the earliest and latest spinal fluid collections to determine the risk of traumatic bleeding; we also noted any complications. Antiplatelet medication use within 1 week of lumbar puncture was associated with a 3% incidence of bloody tap and 4% incidence of traumatic tap that cleared. In the group of patients who waited for a lumbar puncture at least 4 weeks after discontinuation of antiplatelet drug, there was a 5% incidence of bloody or traumatic tap. There was no difference in rates of bleeding between aspirin versus aspirin plus clopidogrel. The rate of hematoma complications was highest in the group of patients on aspirin at the time of the procedure (0.7%). Aspirin or clopidogrel, or both, did not meaningfully increase hemorrhagic complications in patients undergoing lumbar punctures, regardless of when the antiplatelet drug was discontinued relative to the time of the procedure.