Ictal-interictal continuum: A proposed treatment algorithm

Abstract

The ictal-interictal continuum (IIC) is characterized by periodic and/or rhythmic EEG patterns that occur with relative high frequency in critically ill patients. Several studies have reported that some patterns seen within the continuum are independently associated with poor outcome. However there is no consensus regarding when to treat them or how aggressive treatment should be. In this review we examine peer-reviewed original scientific articles, guidelines and reviews indexed in PubMed and summarize current knowledge related to the ictal-interictal continuum. A treatment algorithm to guide management of critically ill patients with EEG patterns that fall along the IIC is proposed. The algorithm-based on best current practice in adults-takes into account associated clinical events, risk factors for developing seizures, response to medication trials and biomarkers of neuronal injury.

Keywords: Continuous EEG monitoring; Critically ill patients; ICU; Ictal–interictal continuum; Periodic discharges; Rhythmic delta activity; Treatment algorithm.