Early Quantitative Gamma-Band EEG Marker is Associated with Outcomes After Cardiac Arrest and Targeted Temperature Management

Background Brain recovery after cardiac arrest (CA) is sensitive to temperature. Yet the effect of temperature management on different EEG frequency bands has not been elucidated. A novel quantitative EEG algorithm, sub-band information quantity (SIQ), was applied to evaluate EEG recovery and outcomes after CA. Methods Twenty-four Wistar rats undergoing 7-min CA were randomly assigned to immediate hypothermia (32–34 °C), normothermia (36.5–37.5 °C), or hyperthermia (38.5–39.5 °C) ( n = 8). EEG was recorded continuously for the first 8 h and then for serial 30-min epochs daily. The neurologic deficit score (NDS) at 72-h was the primary functional outcome. Another four rats without brain injury were added as a control. Results Better recovery of gamma-band SIQ was found in the hypothermia group (0.60 ± 0.03) compared with the normothermia group (0.40 ± 0.03) ( p