Abstract 418: Categorization of Post-Cardiac Arrest Patients According to the Pattern of Amplitude-Integrated Electroencephalography After Return of Spontaneous Circulation: Analysis of Long-Term Prognosis
Introduction: Amplitude-integrated electroencephalography (aEEG) is a type of quantitative EEG easily interpreted by emergency physicians and intensivists at the bedside. We previously reported that categorizing post-cardiac arrest patients according to the pattern of aEEG, after return of spontaneous circulation (ROSC), could help predict the neurological function at hospital discharge (Critical Care. 2018;20:226). In post-cardiac arrest patients, increasing importance is being placed on long-term prognosis. In this study we evaluated the neurological outcome of patients in each category from our previous study, one year after cardiac arrest. Methods: We assessed the outcomes of patients who received post-cardiac arrest care, including targeted temperature management (TTM) and aEEG monitoring, in our tertiary emergency center, between March 2013 and April 2017. The patients were divided into four categories: C1 included those who displayed continuous normal voltage (CNV), within 12 hours of ROSC, and the best aEEG pattern in post-cardiac arrest patients; C2 included those who recovered CNV between 12 and 36 hours after ROSC; C3 included those with no CNV up to 36 hours after ROSC; and C4 included those who revealed burst suppression any time after ROSC. A good outcome was defined as a cerebral performance category (CPC) of 1 or 2, one year after cardiac arrest. Results: A total of 60 patients, with a median age of 60 years, were assessed; of them, 41 (68%) had an initial shockable rhythm. A good outcome was recorded in 18/19 (95%) C1 patients, 8/14 (57%) C2 patients, 1/10 (10%) C3 patients, and 0/14 C4 patients. Three patients could not be categorized because the recording period was too short. Conclusion: The categorization of post-cardiac arrest patients according to the pattern of aEEG after ROSC may be useful to predict long-term neurological function. C1 patients had excellent prognosis, while C3 and C4 patients had poor prognosis. However, one patient in the C3 group had CPC 3 at hospital discharge and then recovered to CPC 2 within one year. Withdrawal of care should be considered cautiously, using a multimodal approach, for patients in this category. C2 patients have borderline prognosis and are targets for intensive post-cardiac neurological care.