"Pseudo-subarachnoid hemorrhage sign" on early brain computed tomography in out-of-hospital cardiac arrest survivors receiving targeted temperature management

Abstract

Purpose: Newly updated guidelines suggest brain computed tomography for out-of-hospital cardiac arrest survivors to identify a neurologic cardiac arrest cause. We hypothesized that the "pseudo-subarachnoid hemorrhage" (p-SAH) sign in cardiac arrest survivors is associated with poor outcome.

Materials and methods: We retrospectively evaluated the registries of 2 tertiary hospitals, identifying 836 adult (≥18 years) patients achieving return of spontaneous circulation after out-of-hospital cardiac arrest. Among them, 398 patients with brain computed tomography within 6 hours after return of spontaneous circulation and received targeted temperature management from 2009 to 2014 were included. Clinical characteristics and outcomes of patients with and without p-SAH were compared.

Results: The prevalence of p-SAH sign was 8.0%. The p-SAH group more frequently had asystole as first rhythm and nonwitnessed arrest, predominantly resulting from asphyxia (56.3%). Targeted temperature management characteristics were not different between groups, although the p-SAH cohort had worse neurologic outcomes at discharge (100% vs 67.2%; P < .001). Pseudo-subarachnoid hemorrhage had 11.5% sensitivity, 100% specificity, 100% positive predictive value, and 32.8% negative predictive value for poor neurologic outcome.

Conclusions: Pseudo-subarachnoid hemorrhage sign might be one of the simple methods to identify poor neurologic outcome early. However, further prospective studies will be needed to clarify the clinical implication of the p-SAH sign.

Keywords: Brain computed tomography; Out-of-hospital cardiac arrest; Prognosis; Pseudo-subarachnoid hemorrhage; Targeted temperature management.