Clinical Evolution After a Non-reactive Hypothermic EEG Following Cardiac Arrest

Background: Lack of electroencephalography (EEG) background reactivity during therapeutic hypothermia (TH) has been associated with poor outcome in post-anoxic comatose patients. However, decision on intensive care withdrawal is based on normothermic (NT) evaluations. This study aims at exploring whether patients showing recovery of EEG reactivity in NT after a non-reactive EEG in TH differ from those remaining non-reactive. Methods: Patients with non-reactive EEG during TH were identified from our prospective registry of consecutive comatose adults admitted after successful resuscitation from CA between April 2009 and June 2014. Variables including neurological examination, serum neuron-specific enolase (NSE), procalcitonin, and EEG features were compared regarding impact on functional outcome at 3months. Results: Seventy-two of 197 patients (37%) had a non-reactive EEG background during TH with thirteen (18%) evolving towards reactivity in NT. Compared to those remaining non-reactive (n=59), they showed significantly better recovery of brainstem reflexes (p<0.001), better motor responses (p