Refractory status epilepticus: A prospective observational study

Abstract
Status epilepticus (SE) that is resistant to two antiepileptic compounds is defined as refractory status epilepticus (RSE). In the few available retrospective studies, estimated RSE frequency is between 31% and 43% of patients presenting an SE episode; almost all seem to require a coma induction for treatment. We prospectively assessed RSE frequency, clinical predictors, and outcome in a tertiary clinical setting. Over 2 years we collected 128 consecutive SE episodes (118 patients) in adults. Clinical data and their relationship to outcome (mortality and return to baseline clinical conditions) were analyzed. Twenty-nine of 128 SE episodes (22.6%) were refractory to first- and second-line antiepileptic treatments. Severity of consciousness impairment and de novo episodes were independent predictors of RSE. RSE showed a worse outcome than non-RSE (39% vs. 11% for mortality; 21% vs. 63% for return to baseline clinical conditions). Only 12 patients with RSE (41%) required coma induction for treatment. This prospective study identifies clinical factors predicting the onset of SE refractoriness. RSE appears to be less frequent than previously reported in retrospective studies; furthermore, most RSE episodes were treated outside the intensive care unit (ICU). Nonetheless, we confirm that RSE is characterized by high mortality and morbidity.