Status epilepticus. A perspective from the neuroscience intensive care unit

Abstract

Patients with GCSE and NCSE are common and may present to the emergency department or the NICU. In the NICU, NCSE is a more common presentation than GCSE. In the emergency department, GCSE commonly evolves to NCSE, either as a late sequela of prolonged SE or due to partial treatment with antiepileptic medication or neuromuscular blocking agents. In the emergency department, acute cerebral injuries are commonly found in patients presenting with SE, regardless of whether they have preexisting epilepsy. In the NICU, almost by definition, SE occurs in patients with acute cerebral injuries. Status epilepticus has been found to evolve sequentially through several stages, the end-point of which is a condition of refractory SE leading to neuronal necrosis and permanent cerebral injury. The responsiveness of SE to treatment is time-dependent. This makes early diagnosis and initiation of treatment essential. Most published treatment algorithms stress a 60-minute time window from the diagnosis of SE to its successful control. Unfortunately, the practical problem of patients with SE accessing such treatment protocols has been overlooked. Our preliminary (unpublished) data suggest that this access problem must be solved for treatment algorithms to improve the outcome of SE. In the NICU, access is less of a problem, and the determining factor is early diagnosis by NICU personnel. Because these patients usually sustain NCSE, which can be difficult to diagnose, a high index of suspicion and, optimally, continuous EEG monitoring are necessary for early diagnosis. NICU patients may be more susceptible to the ravages of SE because of their preexisting cerebral injuries. Expedited treatment may therefore be more important in this patient group. Clinical management of SE requires meticulous attention to ventilation and oxygenation, maintenance of adequate blood pressure, prevention of hyperthermia, and close monitoring for cardiac abnormalities. No specific medication is ideal for controlling SE. The knowledgeable and prompt use of intravenous lorazepam, a diazepam-phenytoin combination, or phenobarbital is acceptable as first-line treatment and as part of a systematic treatment algorithm. Refractory SE has been treated conventionally with high-dose intravenous barbiturate coma. Recent evidence suggests that high-dose intravenous midazolam may provide a useful alternative.