Abstracts

Rationale: To determine the effects of short duration versus longer duration prophylaxis of Levetiracetam on cognitive / functional outcomes in aneurysmal subarachnoid hemorrhage and on risk of development of delayed seizures. Methods: We performed the chart review of 116 consecutive patients admitted at Cedars Sinai from January 2010 to December 2015 with aneurysmal subarachnoid hemorrhage who received Levetiracetam seizure prophylaxis 500 mg twice daily, or more than 500 mg for at least 3 days versus 7 days or more. We compared the length of ICU stay, delta GCS at discharge, modified Rankin score (MRS) at 30 days and 90 days if available, and incidence of delayed seizures defined as occurring after day three. Results: The patients who were treated with a low dose Levetiracetam prophylaxis have a statistically significant improvement in cognitive and functional outcome as measured by the MRS at discharge, compared to those treated with a higher dose (p < 0.049). In addition, the low dose Levetiracetam prophylaxis produced a shorter ICU stay (p=0.624). However, there is no difference in cognitive or functional outcome (p < 0.0625) and ICU stay (p < 0.668) between the patients on short duration versus long duration Levetiracetam therapy. The incidence of early onset and delayed onset seizure during hospitalization were 16.3 % and 6% respectively. 30% of the patients with seizures, including early and late onset seizures have a severe cognitive outcome (MRS >/= 5), compared to 20% for those without seizure (p< 0.491). Furthermore, 66.7% of patients with delayed seizure have delayed cerebral ischemia, compared to 25% with early onset seizure and 17.8 % without seizure (p < 0.017). Half of the patients with delayed seizure received short duration Levetiracetam therapy and the other half received long duration Levetiracetam therapy without change in seizure occurrence and timing. Conclusions: The results of this study suggest that low dose Levetiracetam improves cognitive and functional outcomes at discharge compared to high dose prophylaxis and may shorten length of ICU stay. However, there is no difference between short duration and long-duration Levetiracetam therapy. The presence of delayed ischemia suggests a trend towards an increased risk for delayed onset seizure, but long-term prophylaxis does not decrease the risk of delayed onset seizures when compared to short-term prophylaxis. These findings are encouraging and warrant a prospective study. Funding: No funding was received