Abstract 10: Early Neuroprognostication After Refractory VF/VT Cardiac Arrest Requiring ECPR

Abstract

Background: Extracorporeal cardiopulmonary resuscitation (ECPR) can improve survival for refractory ventricular fibrillation (VF) cardiac arrest. Early prognostication will be critical to focus this resource-intensive care to patients likely to benefit. Objectives: The aim of this study is to examine the efficacy of current neuroprognostication tools early in the setting of ECPR for refractory VF. Methods: Consecutive patients transported for the University of Minnesota ECPR program and surviving to hospital admission between December 2015 and May 2019 were assessed. All patients received neurologic assessment with head CT, continuous EEG, cerebral near-infrared spectroscopy (NIRS), biomarkers including S100B and neuron specific enolase (NSE), and neurologic exam. All patients were considered viable unless they developed refractory shock, devastating brain injury, or family requested cessation of efforts. For this analysis, patients were divided into two groups: 1) neurologically favorable survival (CPC 1-2) and 2) those who died or had CPC 3-4. Data from the first 24 hours of hospital admission were used. Results: Of 168 patients, 130 patients survived to hospital admission. Of these, 42% (54/130) survived neurologically favorable. Abnormalities on admission head CT were predictive of poor outcomes; cerebral edema was 100% specific and 30% sensitive for poor outcomes while anoxic injury provided 98% specificity and 39% sensitivity. Admission NSE levels greater than three times the upper limit of normal were predictive with 98% specificity and 26% sensitivity for poor outcome. Admission S100B was highly variable failing to discriminate patient outcome. Absence of brainstem reflexes at 24 hours had 100% specificity and 32% sensitivity. An isoelectric EEG at 24 hours had 100% specificity and 20% sensitivity. NIRS did not predict poor outcomes. When combined, ≥ 1 of the following: anoxic injury on CT, edema on CT, NSE, absence of brainstem reflexes, isoelectric EEG have a specificity of 96% and sensitivity of 67% for poor outcome. Conclusions: Neuroprognostication after 24 hours of hospital admission may be possible in the refractory VF population requiring ECPR. High specificity is possible but sensitivity is limited. Further study is needed.