Continuous EEG Monitoring in Intensive Care Unit

Abstract

Trends of electroencephalogram (EEG) over 24 to 48 hours can help in prognostication in patients. Continuous electroencephalography (cEEG) allows for “real-time” bedside evaluation of cerebral function and can help to monitor patients in intensive care units. Lack of expertise in interpretation of the long-term EEG patterns and controversies in treatment implications have restricted the widespread use of this modality. This review summarizes the indications, techniques, duration, and pitfalls in cEEG monitoring. Compared with routine planned EEG, use of cEEG monitoring increases the sensitivity to detect nonconvulsive seizures (NCS) or nonconvulsive status epilepticus (NCSE) in unresponsive patients with no or subtle clinical signs of seizures. cEEG helps in reducing the overall intensive care unit (ICU) stay by timely detection of possible ischemic or ictal insults, alleviating the need for costlier imaging tests, and by precise drug adjustment in case of SE. However, standardization of the technical terms for wider applicability is needed. Analysis of automated computerized assays in seizure detection and their clinical role and addressing the technical aspects in long-term recordings should be evaluated; cEEG is gaining an important role in the multiparametric neuro-critical care units. Development of defined guidelines for the indications and application of cEEG, technological advances, and ongoing refinements are expected to enhance its utility in clinical practice.

Keywords

continuous EEG - nonconvulsive status epilepticus - nonconvulsive seizures - neurocritical care unit - encephalopathy

• References

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