Association Between Induced Burst Suppression and Clinical Outcomes in Patients With Refractory Status Epilepticus
Urs Fisch, Anja L. Jünger, Sira M. Baumann, Saskia Semmlack, Gian Marco De Marchis, Sabina Hunziker, Stephan Rüegg, Stephan Märsch, Raoul Sutter
Abstract
<h3>Objective:</h3> To investigate the frequency of induced electroencephalographic (EEG) burst-suppression pattern during continuous intravenous anesthesia (IVAD) and associated outcomes in adult patients treated for refractory status epilepticus (RSE). <h3>Methods:</h3> Patients with RSE treated with anesthetics at a Swiss academic care center from 2011-2019 were included. Clinical data and semiquantitative EEG analyses were assessed. Burst-suppression was categorized as incomplete burst-suppression (with ≥20% and <50% suppression proportion) or complete burst-suppression (with ≥50% suppression proportion). The frequency of induced burst-suppression, and association of burst-suppression with outcomes (persistent seizure termination, in-hospital survival, and return to premorbid neurologic function) were endpoints. <h3>Results:</h3> We identified 147 patients with RSE treated with IVAD. Among 102 patients without cerebral anoxia, incomplete burst-suppression was achieved in 14 (14%) with a median of 23 hours (interquartile range [IQR] 1-29) and complete burst-suppression was achieved in 21 (21%) with a median of 51 hours (IQR 16-104). Age, Charlson comorbidity Index, RSE with motor symptoms, and the Status Epilepticus Severity Score (STESS) were identified as potential confounders in univariable comparisons between patients with and without any burst-suppression. Multivariable analyses revealed no associations between any burst-suppression and the predefined endpoints. However, among 45 patients with cerebral anoxia, induced burst-suppression was associated with persistent seizure termination (72% without vs. 29% with burst-suppression, p=0.004) and survival (50% vs. 14% p=0.005). <h3>Conclusions:</h3> In adult patients with RSE treated with IVAD, burst-suppression with ≥50% suppression proportion was achieved in every fifth patient and not associated with persistent seizure termination, in-hospital survival or return to premorbid neurologic function.