Introduction: Prophylactic antiepileptic drug (AED) administration following non-traumatic subarachnoid hemorrhage (SAH) remains controversial. AEDs have been associated with increased risk of vasospasm, neurologic worsening, and delayed functional recovery, without demonstrating clear benefit. We sought to prospectively assess the impact not receiving prophylactic AEDs had on the incidence of seizures following SAH.
Methods: We performed a prospective cohort trial evaluating consecutive cases of SAH admitted to our institution between 2005 and 2010. During this time, the protocol for administration of prophylactic AEDs changed to generate the 2 cohorts utilized for comparison: a) between Feb. 2005 - July 2007 all patients received prophylactic AEDs upon admission, and b) after July 2007 all patients either did not receive prophylactic AEDs or had AEDs immediately discontinued if initiated at an outside hospital. The primary end-point was development of seizures diagnosed either clinically or electrographically (EEG) in patients unable to participate in an exam or in whom clinical suspicion of seizure activity existed.
Results: During the study period, 353 patients with SAH were available for analysis; 41% received prophylactic AEDs for a mean duration 14±8 days. Mean age was 54±12 years, 85% were of aneurysmal etiology, and median H&H grade was 3 (IQR 1). Across all cohorts, 10% of patients suffered clinical and/or electrographic seizures, most frequently occurring within 24-hrs of ictus (49%). The incidence of seizures did not vary significantly based on receipt of prophylactic AEDs (10 vs 9%, p=0.30). This finding persisted despite adjustment for significant univariate predictors of seizure occurrence (H&H grade, cisternal blood burden, and intraventricular hemorrhage; p=0.24).
Conclusions: Prospective analysis demonstrates that prophylactic AED administration following SAH does not significantly reduce the risk of seizure occurrence. Further trials are necessary to determine whether AED prophylaxis confers beneficial effects on long-term seizure control or clinical outcome.
Patient Care: Prophylactic antiepileptic medication does not confer a benefit in reducing seizures following SAH as evidenced by these findings; discontinuing their blanket use may improve neurologic outcomes and reduce costs associated with SAH
Learning Objectives: By the conclusion of this session, participants should be able to: 1) describe the risk factors for seizure development following subarachnoid hemorrhage, and 2) cite evidence for discontinuing ubiquitous prophylactic antiepileptic administration in SAH