No abstract

Introduction: Head computed tomography (CT) is frequently performed in survivors of out-of-hospital cardiac arrest (OHCA). However, the clinical utility of routine, early head CT in these patients is not well understood. We sought to characterize the associations between findings on early head CT with presenting characteristics and outcomes in survivors of OHCA. Hypothesis: Presence of early intracranial swelling is associated with poor outcomes. Methods: This is a retrospective analysis from a multicenter cohort of 432 patients with non-traumatic OHCA between 2/1/17 through 4/1/19. Patients were included if they underwent head CT <24 hrs after return of spontaneous circulation. Head CT findings were based on reads performed by local radiologists. Intracranial swelling was defined as loss of gray-white matter differentiation, sulcal effacement, and/or cerebral edema. Underlying cause of OHCA was adjudicated by trained physicians. Baseline characteristics and outcomes were compared between those with and without intracranial swelling. Result: Early head CT (<24 hrs) was performed in 378 (87.5%) patients with OHCA. Intracranial swelling was present in 97 (25.7%) patients with early head CT, and 14 (3.7%) had evidence of intracranial hemorrhage (ICH, Table). Of the patients presenting with ICH, 3/14 (21.4%) had shockable rhythms, 7/14 (50%) had subarachnoid hemorrhage, and ICH was the adjudicated cause of arrest in 10/14 (71.4%) patients. Patients with intracranial swelling were younger, less likely to have presented with a shockable rhythm, cardiac etiology, and witnessed OHCA. They were more likely to have a suppressed EEG, anoxia on MRI, and were less likely to survive to hospital discharge. Conclusions: In survivors of non-traumatic OHCA, routine, early (<24 hrs) head CT identified ICH in 3.7% of patients, and ICH was the adjudicated cause of arrest in 2.6% of patients. Intracranial swelling was present in more than 1/4 of patients, and associated with poor outcomes.