Abstract 9720: A New Window on a Cerebral Penumbra at Risk for a Secondary Ischemic Brain Injury in Post-Cardiac Arrest Patients

Abstract

Aim: This study aimed to investigate new target having potential neuroprotective effect against a secondary ischemic brain injury in post out-of-hospital cardiac arrest (OHCA) patients. Methods: This study analyzed physiological variables among OHCA patients with good or poor neurological outcomes despite having normal diffusion-weighted image findings before targeted temperature management (TTM). The factors affecting cerebral perfusion after OHCA, such as the time-weighted average (TWA) of arterial carbon dioxide (PaCO 2 ), oxygen (PaO 2 ), and mean arterial pressure (MAP); and the intracranial pressure (ICP) and quotient albumin ratio (Qalb), measured at 0 and 24 h from the return of spontaneous circulation (ROSC), were analyzed retrospectively using prospectively collected data. The primary outcome was the association between the factors and poor neurological outcome. Results: Fifty-one patients were included in this study. Among them, 11 had poor neurological outcomes. The pre-hospital factors such as anoxic time, initial rhythm; and TWA of physiological factors (PaCO 2 , PaO 2 , and MAP), were not significantly different between groups (p > 0.05). The inter-group comparisons of Qalb at 0 and 24 h were not significant (p > 0.05), whereas Qalb (median [interquartile range]) significantly increased from 0 to 24 h in the poor outcome group (0.007 [0.003 - 0.011] to 0.013 [0.005 - 0.029]; p = 0.04). Simultaneously, the ICP of the poor outcome group significantly increased over time (12.0 mmHg [8.1 - 13.0] to 16.0 mmHg [9.3 - 22.4]; p = 0.03), and higher than those of good outcome group at 24 h (11.0 mmHg [6.5 - 16.0] vs. 16.0 [9.3 - 22.4]; p < 0.01). Conclusion: Blood-brain barrier disruption and increasing ICP were apparent in OHCA patients who progressed into poor outcome despite no significant difference of brain injury before TTM compared with those of good outcome. These factors may be the key window on strategy to prevent the secondary ischemic brain injury after OHCA.