EEG Reactivity in Coma After Cardiac Arrest: Is it Enough to Wake Up the Dead?

Abstract

EEG Reactivity as Predictor of Neurological Outcome in Postanoxic Coma: A Multicenter Prospective Cohort Study Admiraal MM, van Rootselaar AF, Hofmeijer J, Hoedemaekers CWE, van Kaam CR, Keijzer HM, van Putten MJAM, Schultz MJ, Horn J. Ann Neurol. 2019. doi:10.1002/ana.25507. Epub ahead of print. PMID: 31124174 Objective: Outcome prediction in patients after cardiac arrest (CA) is challenging. Electroencephalogram reactivity (EEG-R) might be a reliable predictor. We aimed to determine the prognostic value of EEG-R using a standardized assessment. Methods: In a prospective cohort study, a strictly defined EEG-R assessment protocol was executed twice a day in adult patients after CA. The EEG-R was classified as “present” or “absent” by 3 EEG readers, blinded for patient characteristics. Uncertain reactivity was classified as “present.” Primary outcome was best Cerebral Performance Category (CPC) in 6 months after CA, dichotomized as “good” (CPC 1-2) or “poor” (CPC 3-5). The EEG-R was considered reliable for predicting poor outcome if specificity was ≥95%. For good outcome prediction, a specificity of ≥80% was used. Added value of EEG-R was the increase in specificity when combined with EEG background, neurological examination, and somatosensory evoked potentials (SSEP). Results: Of 160 patients enrolled, 149 were available for analyses. The absence of EEG-R for poor outcome prediction had specificity of 82% and sensitivity of 73%. For good outcome prediction, specificity was 73% and sensitivity was 82%. Specificity for poor outcome prediction increased from 98% to 99% when EEG-R was added to a multimodal model. For good outcome prediction, specificity increased from 70% to 89%. Interpretation: The EEG-R testing in itself is not sufficiently reliable for outcome prediction in patients after CA. For poor outcome prediction, it has no substantial added value to EEG background, neurological examination, and SSEP. For prediction of good outcome, EEG-R seems to have added value. This article is protected by copyright. All rights reserved.