Prognostic value of electroencephalography pattern in prediction of survival and early myoclonus after cardiac arrest

Abstract

Background Evolution of the electroencephalography (EEG) background pattern is a robust contributor to the prediction of poor or good outcome of comatose patients after cardiac arrest (CA). Aim The aim of the study was to use EEG as a prognostic tool for the prediction of survival after CA and the incidence of early postanoxic myoclonus. Patients and methods We enrolled 40 patients, post-CA. A 30-min EEG was performed on all patients, as soon as possible after the patients had arrived in the ICU using a portable EEG. Results Out of the 40 patients studied, 29 (72.5%) were alive while 11 (27.5%) patients were dead: Regarding patterns of EEG, 86.2% of alive patients had a benign pattern, while 63.6% of dead patients had a highly malignant pattern. Regarding the cerebral performance category (CPC), 79.3% of alive patients had cerebral performance grade 1 (CPC 1) while 54.5% of dead patients had CPC 4. Frequency of seizures after resuscitation was significantly higher in dead patients (45.5%) versus 17.2% in alive patients (P = 0.03). Conclusion Benign EEG patterns and CPC 1 and CPC 2 were correlated to good outcome in patients post-CA in comparison to malignant EEG pattern and CPC 3 and CPC 4, respectively. Presence of early posthypoxic myoclonus had been invariably related to poor outcome.