Abstracts

Rationale: Seizures are a common complication of aneurysmal subarachnoid hemorrhage (aSAH). Phenytoin has been the gold standard of prophylactic anti-epileptic therapy. The objective of this study was to demonstrate that levetiracetam is equivalent to phenytoin as a prophylactic antiepileptic medication and that levetiracetam does not result in statistically significant adverse hospital outcomes when compared to phenytoin. Methods: We retrospectively studied 107 patients with aSAH on long-term EEG monitoring (LTM). Our data was collected from 2003 until 2008. We collected demographics, EEG data, anti-epileptic therapy, and condition at admission and discharge by chart review. Functional outcome was assessed by Glascow outcome scale (GOS), modified Rankin scale (mRS), Karnofsky Scale, and the Barthel index. A student’s t-test was performed to assess statistical significance between the phenytoin group and the levetiracetam group. Results: 17 patients received levetiracetam and 89 patients received phenytoin as prophylactic therapy. Mean age, Glascow coma scale (GCS), number of aneurysms and size of the largest aneurysm were not statistically different between the two groups. However, the Hunt-Hess (HH) (levetiracetam 2 (SD 1.27); phenytoin 2.70 (SD 1.21) p<0.03) and Fisher score (levetiracetam 2.94 (SD 1.20); phenytoin 3.60 (SD 0.71) p<0.002) were statistically significantly different with phenytoin having worse admission scores. More patients in the phenytoin group had a ventriculostomy (76% vs. 78% in the levetiracetam group) and Licox (41% vs. 35% in the levetiracetam group). However, more patients in the levetiracetam group had intraventricular hemorrhage (70% vs. 66% in the phenytoin group). Mean number of ICU days and hospital days did not differ significantly. There was a statistically significant difference favoring the levetiracetam group in both GCS (levetiracetam 13.88 (SD 2.98); phenytoin 11.39 (SD 4.99) p <0.05) and in functional outcome as assessed by the GOS (levetiracetam 4.59 (SD 2.90); phenytoin 3.33 (SD 1.69) p <0.01) at the time of discharge. All other functional scales (mRS, Karnofsky, and Barthel) showed a trend favoring levetiracetam; however this did not reach statistical significance. Seizures were detected in 19% of patients on LTM with nonconvulsive seizures and nonconvulsive status epilepticus in 7% and 3% of patients, respectively. Seizures were associated with a higher mortality (27% as opposed to 19% in the non-seizure patients.) Conclusions: Seizure incidence at our institution in aSAH patients is comparable to the incidence reported in literature. Although confounded by selection bias, we demonstrated that patients appeared to do as well or slightly better (significantly better based on GCS / GOS at discharge) on levetiracetam. Levetiracetam appears to be a viable alternative to phenytoin for use as a prophylactic antiepileptic drug after aSAH.