Abstract Body: Background: Initial care after out-of-hospital cardiac arrest (OHCA) poses major challenges to clinical teams due to diverse arrest etiologies and the potential need for time-sensitive interventions. Emergency department-based evaluation of these patients is crucial for identifying treatable causes of arrest. Recent data from one academic hospital highlights the potential importance of initial broad computed tomography (CT) immediately following resuscitation.

Objective: To assess the ability of early post-arrest CT imaging to diagnose potential etiologies and sequelae of OHCA.

Methods: We employed a registry of consecutive OHCA cases admitted to 3 hospitals within the University of Pennsylvania Health System between 1/2019-10/2020, collecting demographic, arrest, and post-arrest clinical data. Inclusion criteria included age >18 y, OHCA with return of spontaneous circulation (ROSC). We abstracted CT data including findings, contrast use, and timing, and subsequent clinical notes to assess for interventions performed based on CT findings from the EHR. KDIGO definition was used for acute kidney injury (AKI). SAS software was used for data analysis.

Results: A total of 161 OHCA patients were included (mean age 60.8±15.6y; 42% female). Initial shockable rhythms were present in 16%, with 70% witnessed and 39% receiving bystander CPR. 154 patients survived to admission, and 41 survived to discharge. 117 patients underwent CT imaging in the ED: 117 underwent head CT, 87 chest CT, and 64 abdomen/pelvis CT. Median time to any first CT was 2.0h (IQR:1.4,2.8). Intracranial hemorrhage was diagnosed in 5/117 patients (4.3%); 3 received conservative therapy. Cerebral edema was found in 30/117 patients (25.6%), 10 received treatment. Pulmonary embolism was diagnosed in 8/87 cases (9.2%), 7 of which were acute and treated pharmacologically and/or mechanically. Aspiration and/or pneumonia, pneumonitis, bronchitis, bronchiolitis was found on 65/84 cases (74.7%), 30 received antibiotics. Deep venous thrombosis was detected in 3/64 patients (4.7%), 2 received anticoagulation. We found no significant differences in AKI rates with the use of contrast compared to patients receiving no contrast (p=0.93).

Conclusion: These results confirm and extend other reports emphasizing the potential value for routine use of CT imaging post-ROSC. Implementing larger scale prospective studies comparing such protocols and standard-of-care is important to determine impact on OHCA outcomes.