Early EEG contributes to multimodal outcome prediction of postanoxic coma

Abstract

Objectives:Early identification of potential recovery of postanoxic coma is a major challenge. We studied the additional predictive value of EEG.Methods:Two hundred seventy-seven consecutive comatose patients after cardiac arrest were included in a prospective cohort study on 2 intensive care units. Continuous EEG was measured during the first 3 days. EEGs were classified as unfavorable (isoelectric, low-voltage, burst-suppression with identical bursts), intermediate, or favorable (continuous patterns), at 12, 24, 48, and 72 hours. Outcome was dichotomized as good or poor. Resuscitation, demographic, clinical, somatosensory evoked potential, and EEG measures were related to outcome at 6 months using logistic regression analysis. Analyses of diagnostic accuracy included receiver operating characteristics and calculation of predictive values.Results:Poor outcome occurred in 149 patients (54%). Single measures unequivocally predicting poor outcome were an unfavorable EEG pattern at 24 hours, absent pupillary light responses at 48 hours, and absent somatosensory evoked potentials at 72 hours. Together, these had a specificity of 100% and a sensitivity of 50%. For the remaining 203 patients, who were still in the “gray zone” at 72 hours, a predictive model including unfavorable EEG patterns at 12 hours, absent or extensor motor response to pain at 72 hours, and higher age had an area under the curve of 0.90 (95% confidence interval 0.84–0.96). Favorable EEG patterns at 12 hours were strongly associated with good outcome. EEG beyond 24 hours had no additional predictive value.Conclusions:EEG within 24 hours is a robust contributor to prediction of poor or good outcome of comatose patients after cardiac arrest.

Multimodal Outcome Prognostication After Cardiac Arrest and Targeted Temperature Management: Analysis at 36 °C

“…Our findings show high specificity of a first unreactive EEG background for predicting poor outcome at 36°C. Besides background amplitude (31,32), reactivity has been repeatedly described (10,12,(33)(34)(35); however, as opposed to this study, those description rely on patients treated with 33°C and the first EEG recorded during TTM is generally not included as a predictor in current recommendations (28,36). We acknowledge that lack of standardized stimulations (24) remains a relevant limitation.…”

Combination of Initial Neurologic Examination, Quantitative Brain Imaging and Electroencephalography to Predict Outcome After Cardiac Arrest

“…[20][21][22] Prior work has examined prognostic tests such as neurologic examination, SSEP, biomarkers, EEG, brain CT, and MRI in isolation. [9][10][11][12][13][14][15][16][17][18] Recent work has tested predictive value of multiple modalities, but the ideal combination is not known. [28][29][30][31][32] Importantly, not all tests are necessary for all patients and some facilities may not offer all of these modalities.…”

“…[9][10][11][12][13][14][15][16][17][18][19] The combination of multiple modalities is recommended because no single test short of physical examination meeting brain death criteria can predict neurologic outcome correctly. [20][21][22] We previously reported that combining the initial neurologic examination with continuous EEG (cEEG) was superior to any individual test for predicting outcome after CA.…”

Myoclonus after Cardiac Arrest: Where Do We Go from Here?

“…Neurophysiological testing and neurological examination have been well studied as useful indicators of outcomes (1,2). One particular examination finding of prognostic importance is early posthypoxic myoclonus (PHM).…”