Abstract 407: Utility of Abnormal Head Computed Tomography in Predicting Outcome in Out of Hospital Cardiac Arrest Victims Resuscitated and Subsequently Placed on Targeted Temperature Management

Abstract

Introduction: Head computed tomography (HCT) is often performed to assess for hypoxic-ischemic brain injury in resuscitated out of hospital cardiac arrest (OHCA) patients. Our primary objective was to assess whether cerebral edema (CE) on early HCT is associated with poor survival and neurologic outcome post OHCA. Methods: We included subjects from a prospectively collected cardiac arrest database of OHCA adult patients who received targeted temperature management (TTM) at two academic suburban hospitals from 2009-Sept-2018. Cases were included if a HCT was performed in the emergency department (ED). Patient demographics and cardiac arrest variables were collected. HCT results were abstracted by study authors from radiology reports. HCT findings were categorized as no acute disease, evidence of CE, or excluded (bleed, tumor, stroke). Outcomes were survival to discharge or cerebral performance scores (CPC) at discharge of three or four (poor neurologic outcome). Descriptive statistics, univariate, multivariate, survival, and interrater reliability analysis were performed. Results: During the study period, there were 425 OHCA, 277 cases had ED HCTs performed; 254 cases were included in the final survival analysis. Patients were predominately male, 189 (65.0%), average age 60.9 years, average BMI of 30.5. Of all cases, 44 (15.9%) showed CE on CT. Univariate analysis demonstrated that CE was associated with 9.2-fold greater odds of poor outcome (OR: 9.23; 95% CI 1.73, 49.2), and 9.1-fold greater odds of death (OR: 9.09: 95% CI 2.4 33.9). In adjusted analysis, CE was associated with 14.9-fold greater odds of poor CPC outcome (AOR: 14.9, 95% CI, 2.49, 88.4), and 13.7-fold greater odds of death (AOR: 13.7, 95% CI, 3.26, 57.4). Adjusted survival analysis demonstrated that patients with CE on HCT had 3.6-fold greater hazard of death than those without CE (HR: 3.56: 95% CI 2.34, 5.41). Interrater reliability demonstrated excellent agreement between reviewers for CE on HCT (κ = 0.86). Conclusion: The results identify that abnormal HCTs early in the post-arrest period in OHCA patients are associated with poor rates of survival and neurologic outcome. Prospective work is needed to confirm whether selection bias or other variables confound this association.