Changes in diagnostic and care trajectories following use of continuous EEG monitoring for neuroprognostication after out of hospital cardiac arrest – a before-and-after study

Continuous electro-encephalography (cEEG) has been added to multimodal protocols to improve neurological prognostication in patients after cardiac arrest. Our aim was to investigate the impact of adding cEEG on diagnostic and care trajectories in clinical practice. Before-and-after study of patients after out of hospital cardiac arrest admitted in 2013-2024 to the intensive care unit in the Netherlands. Data on diagnostic and care trajectories and costs associated with prognostication were compared between patients admitted from 2013-2019, when cEEG was not used to predict the neurological prognosis, and patients admitted from 2019-2024, when cEEG was used. 581 patients were included; 355 when cEEG was not used for neuroprognostication and 226 when cEEG was used. cEEG patterns associated with a poor prognosis were found in 18% of patients; cEEG patterns associated with a good prognosis in 24%. When cEEG was used, the neurologic outcome (either good or poor) could be predicted in an additional 23% of patients (95% CI: 16% to 31%). ICU length of stay did not change when cEEG was used (adjusted estimate: 1% increase in days; 95% CI: -23 to 32%) nor did overall survival (adjusted hazard ratio: 0.93; 95% CI: 0.68 to 1.27). Overall costs did not differ (estimated difference €1040; 95% CI: -4672 to 7078). Use of cEEG increased the number of patients in whom the neurological prognosis after out of hospital cardiac arrest could be predicted correctly. We did not observe changes in subsequent care trajectories although this may have been influenced by self-fulfilling prophecies and/or incorporation bias.