Epidemiology and outcome of status epilepticus in children: a Scottish population cohort study

Aim: To describe the epidemiology and outcomes of convulsive status epilepticus (CSE) since the introduction of buccal midazolam and the change in International League Against Epilepsy definition of CSE to include seizures of at least 5 minutes. Method: All children presenting to paediatric emergency departments with CSE (2011–2017) in Lothian, Scotland, were identified. Data, collated from electronic health records, included patient demographics, clinical characteristics, acute seizure management, and adverse outcomes (for example admission to intensive care). Results: Six hundred and sixty-five children were admitted with CSE who had 1228 seizure episodes (381 males, 284 females; median age 3y 8mo; age range 0–20y 11mo). CSE accounted for 0.38% (95% confidence interval 0.34–0.42) of annual attendances at emergency departments. Annual prevalence was 0.8 per 1000 children aged 0 to 14 years. Thirty-four per cent of children had recurrent CSE. Sixty-nine per cent of seizures lasted 5 to 29 minutes (median duration 10min). Buccal midazolam was given to 30% of children with CSE and had no effect on need for ventilatory support. Seventy per cent of children with CSE required hospital admission. Four per cent resulted in adverse outcome and there were only two deaths. Recurrent seizures, longer duration, and unprovoked seizures increased the odds of adverse outcome. Interpretation: Adverse outcomes have decreased and the use of buccal midazolam is promising. Identifying high-risk groups provides an opportunity for early intervention. These data form the basis for an extensive evaluation of acute seizure management and monitoring long-term outcomes. What this paper adds The annual prevalence of convulsive status epilepticus in Lothian, Scotland, was 0.8 per 1000 children. There was a decrease in case-fatality proportion from 3–9% to 0.2%. Use of buccal midazolam has increased, with no increase in adverse outcomes.