Comparison of pediatric patients with status epilepticus lasting 5-29 min versus ≥ 30 min

The most common thresholds for considering prolonged seizures as status epilepticus (SE) are 5 and 30 min. It is unknown whether these different thresholds (5 or 30 min) identify patient populations with different electroclinical characteristics. We compared the characteristics of patients with SE lasting 5-29 min (SE5-29) with those with SE lasting ≥ 30 min (SE≥ 30). Inclusion criteria were the following: 1) 1 month to 21 years of age at the time of SE, 2) convulsive seizures, and 3) seizure duration ≥ 5 min. Exclusion criteria were the following: 1) exclusively neonatal seizures, 2) psychogenic nonepileptic seizures, or 3) incomplete information about seizure duration. Four hundred forty-five patients (50.1% male) with a median (p25-p75) age at SE of 5.5 (2.8-10.5) years were enrolled. Status epilepticus lasted for 5-29 min in 296 (66.5%) of subjects and for ≥ 30 min in 149 (33.5%). Patients with SE≥ 30 were younger than the patients with SE5-29 at the time of seizure onset (median: 1 versus 2.1 years, p = 0.0007). Status epilepticus as the first seizure presentation was more frequent in patients with SE≥ 30 (24.2% versus 12.2%, p = 0.002). There was a tendency towards a higher rate of abnormalities in the magnetic resonance imaging at baseline in patients with SE≥ 30 (70.5% versus 57.1%, p = 0.061). Differences were not detected in seizure frequency, seizure types, presence of developmental delay, and electroencephalogram abnormalities at baseline. In the pediatric population, SE thresholds of either 5 or 30 min identify groups of patients with very similar electroclinical characteristics, which may influence future definitions of pediatric SE.