Pitfalls in ICU EEG Interpretation: A Retrospective Case Series

Abstract

Background: Electroencephalography (EEG) is increasingly used in intensive care units (ICUs), primarily for seizure detection. However, the complex clinical context of critically ill patients and the dynamic ICU environment can complicate interpretation.

Purpose: To highlight common pitfalls in ICU EEG interpretation and strategies to distinguish epileptic seizures from mimics.

Research Design: Retrospective case series.

Study Sample: Five ICU patients undergoing continuous video EEG (cvEEG) for altered mental status, status epilepticus, or paroxysmal events, with underlying conditions including malignancy, autoimmune encephalitis, neuromodulation therapy, and drug-resistant epilepsy.

Results: Physiological artifacts, such as non-epileptic rhythmic movements, and device-related artifacts (e.g., pacemakers, ventilators) can mimic epileptic seizures. Plateau waves from elevated intracranial pressure may produce deficits resembling epileptic seizures. Accurate differentiation requires attention to clinical context, EEG features, and video correlation. Maintaining a broad differential and avoiding diagnostic anchoring are also essential to prevent misdiagnosis and unnecessary antiseizure medication therapy.

Conclusions: ICU EEG interpretation is challenged by artifacts and non-epileptic movements that mimic epileptic seizures. Awareness of these issues, along with a thoughtful, multidisciplinary approach, is critical for improving diagnostic accuracy and optimizing patient outcomes during cvEEG monitoring.