Abstract 17230: Early Continuous EEG Biomarkers Predicts Neurologic Outcome in Post-cardiac Arrest Rats

Abstract

Introduction: Hypothermic targeted temperature management (TTM) has greatly improved post-cardiac arrest patient outcomes, but also makes prognostication more difficult. In this study, we tested the hypothesis that early continuous EEG biomarkers are associated with neurologic outcome in post-cardiac arrest rats treated with normothermic and hypothermic TTM. Methods: Male rats were instrumented for continuous telemetric EEG (cEEG) recording and then subjected to 8-minute asphyxia cardiac arrest. Eight rats that achieved ROSC underwent either normothermic or hypothermic TTM (37 ± 0.5 °C or 33 ± 0.5 °C) for 24 hours and cEEG monitoring up to 72 hours. Quantitative EEG analysis determined the power density of delta (0.1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz) and sigma (13-18 Hz) frequency bands in all 10 second windows. The mean spectral power and Spearman correlation with time for the first 12 hours after return of spontaneous circulation (ROSC) were calculated and correlated with best neurologic function score (NFS) and survival with good NFS (NFS ≥ 450 out of 500). Results: Over all rats tested, the mean delta band power in the first 12 hours after ROSC was inversely correlated with best neurologic function score and associated with poor outcome (Table and Figure). There was no statistical difference in other frequency bands. Similar findings were present when stratifying into normothermic and hypothermic treatment groups. Conclusions: This study suggests that, the early power density of delta frequency bands from cEEG is a potential predictor of neurologic outcome in a mixed population of rats treated with normothermic and hypothermic TTM.