Abstract 166: Lung Parenchymal And Pleural Findings On Computed Tomography After Out-of-Hospital Cardiac Arrest

Introduction: Lung injury and the acute respiratory distress syndrome (ARDS) are common after out-of-hospital cardiac arrest (OHCA), but the imaging characteristics of lung parenchymal and pleural abnormalities in these patients have not been well-characterized. We aimed to describe the incidence of lung parenchymal and pleural findings among patients who had return of spontaneous circulation (ROSC) after OHCA who underwent computed tomography (CT) of the chest. Methods: This was a retrospective cohort study conducted at two academic hospitals from 2014 to 2019. We included adults with OHCA who received a head-to-pelvis or dedicated chest CT scan. The primary outcome was the incidence of lung parenchymal and pleural abnormalities. CT scans were overread by attending radiologists and lung parenchymal and pleural findings were categorized based on predefined criteria. Data are presented as absolute numbers and percentages. Results: We evaluated 243 eligible patients. Median age was 56 years, 32% were women, and 59% were Caucasian. An initial shockable rhythm was found in 29% and in 71 patients (30%) the etiology of arrest was cardiac. A total of 162 patients underwent head-to-pelvis CT and 81 patients had dedicated chest imaging. The median time from OHCA to CT scan was 2.7 (IQR 2.1-3.8) hours. A total of 190 (78%) of patients had abnormal lung parenchymal or pleural findings. The most common findings are depicted in Table 1. Conclusion: Over three-quarters of patients who survive to the hospital post OHCA have lung parenchymal or pleural abnormalities on CT, the most common of which are aspiration, pulmonary edema, and consolidation/pneumonia. Future planned research will characterize the clinical impact of these findings and whether early chest CT could identify patients at risk for ARDS.