Electroencephalography-based power spectra allow coma outcome prediction within 24 h of cardiac arrest

Abstract

Background: Outcome prediction in comatose patients following cardiac arrest remains challenging. Here, we assess the predictive performance of electroencephalography-based power spectra within 24 h from coma onset. Methods: We acquired electroencephalography (EEG) from comatose patients (n = 138) on the first day of coma in four hospital sites in Switzerland. Outcome was categorised as favourable or unfavourable based on the best state within three months. Data were split in training and test sets. We evaluated the predictive performance of EEG power spectra for long term outcome and its added value to standard clinical tests. Results: Out of 138 patients, 80 had a favourable outcome. Power spectra comparison between favourable and unfavourable outcome in the training set yielded significant differences at 5.2-13.2 Hz and above 21 Hz. Outcome prediction based on power at 5.2-13.2 Hz was accurate in training and test sets. Overall, power spectra predicted patients' outcome with maximum specificity and positive predictive value: 1.00 (95% with CI: 0.94-1.00 and 0.89-1.00, respectively). The combination of power spectra and reactivity yielded better accuracy and sensitivity (0.81, 95% CI: 0.71-0.89) than prediction based on power spectra alone. Conclusions: On the first day of coma following cardiac arrest, low power spectra values around 10 Hz, typically linked to impaired cortico-thalamic structural connections, are highly specific of unfavourable outcome. Peaks in this frequency range can predict long-term outcome.

Background Frequency Patterns in Standard Electroencephalography During Targeted Temperature Management as an Early Prognostic Tool in Out-of-Hospital Cardiac Arrest Survivors: a retrospective cohort study

“…Alpha (8)(9)(10)(11)(12) Hz) is linked to normal, tonic firing mode of the thalamus, which represents normal integrity of the corticothalamic circuit. Our results are consistent with the reports of previous EEG spectral analysisbased studies on CA survivors, which revealed that the patients who showed the presence of alpha and theta frequency bands while undergoing continuous EEG monitoring after CA had favourable outcome as opposed to the patients with a lower frequency band [26,27]. In line with these studies,…”

Alpha-power in electroencephalography as good outcome predictor for out-of-hospital cardiac arrest survivors

“…Alpha oscillations are the salient features during resting or wakefulness, and the change of alpha frequency is related to aging, cognitive function, sensorimotor processing, sleep, and neurodegenerative disease including Alzheimer's disease [38][39][40] . A recent study with OHCA patients reported that the unfavorable outcome group showed lower power spectra in around 10Hz alpha frequency compared with the favorable outcome group 41 . Furthermore, another study found that the prominent alpha peaks were presented in patients with minimally conscious states and in none of the comatose patients 42 .…”

Alpha-power in electroencephalography as good outcome predictor for out-of-hospital cardiac arrest survivors

“…Alpha oscillations are the salient features during resting or wakefulness, and the change of alpha frequency is related to aging, cognitive function, sensorimotor processing, sleep, and neurodegenerative disease including Alzheimer’s disease 38 – 40 . A recent study with OHCA patients reported that the unfavorable outcome group showed lower power spectra in around 10 Hz alpha frequency compared with the favorable outcome group 41 . Furthermore, another study found that the prominent alpha peaks were presented in patients with minimally conscious states and in none of the comatose patients 42 .…”