Seizure Monitoring and Alert System for Brain Monitoring in an Intensive Care Unit

Although monitoring for most organ systems is commonly used in intensive care units (ICU), brain function monitoring relies almost exclusively upon bedside clinical observations. As a result, a large number of nonconvulsive seizures go undiagnosed every day. Recent clinical studies have demonstrated the clinical utility of continuous EEG monitoring in ICU settings. Continuous EEG is a well-established tool for detecting nonconvulsive seizures, cerebral ischemia, cerebral hypoxia, and other reversible brain disturbances in the ICU. However, the utility of EEG monitoring currently depends on the availability of expert medical professionals, and interpretation is labor intensive. Such experts are available only in tertiary care centers. We have designed a seizure monitoring and alert system (SMAS) that utilizes a seizure susceptibility index (SSI) and seizure detection algorithms based on measures that characterize the spatiotemporal dynamical properties of the EEG signal. The SMAS allows distinguishing the organized seizure patterns from more irregular and less organized background EEG activity. The algorithms and initial results in human long-term EEG recordings are described.