Abstracts

Rationale: A high prevalence of nonconvulsive status epilepticus (NCSE) has been reported in critically ill adults and neonates. Recent prospective pediatric studies focus on critically ill children, and show wide variability in the frequency of NCSE. We aimed to determine the prevalence of pediatric NCSE regardless of inpatient setting, and to retrospectively identify risk factors indicating a need for urgent continuous electroencephalography (cEEG). Methods: Medical records from children ages 3 months to 21 years were identified through either 1) searching a clinical EEG database or 2) consecutive inpatient EEG referrals for NCSE over an eight month period.Results: Seventy-five children with a mean age of 7.8 years were studied; 26 had NCSE. Over half of the patients referred were outside of the intensive care unit (ICU). A witnessed clinical seizure was observed in 92% of children with NCSE. Acute cortical imaging abnormalities were significantly more frequent in the NCSE group. A finding of both clinical seizure and acute imaging abnormality was associated with an 82% probability of NCSE. Median duration of monitoring was 11.2 hours; all but one patient with NCSE had electrographic or electroclinical seizures within the first hour of monitoring.Conclusions: We find a high prevalence of NCSE in children, comparable to adult studies, but within a wider range of inpatient settings. Children with unexplained encephalopathy should undergo cEEG. This evaluation is more urgent if certain clinical risk factors are present. Optimal duration of monitoring and the effect of NCSE on prognosis should be studied.