Prognostic factors for out-of-hospital cardiac arrest patients with prolonged low-flow time undergoing extracorporeal cardiopulmonary resuscitation

Abstract

Background: This study aimed to examine factors associated with favourable neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients with low-flow time (LFT) exceeding 60 minutes following extracorporeal cardiopulmonary resuscitation (ECPR).

Methods: This was a secondary analysis of the SAVE-J II study, a retrospective, multicentre, registry study involving 36 participating institutions in Japan. OHCA patients ≥18 years old who underwent ECPR in Japan between January, 2013 and December, 2018 were registered. This study selected the non-hypothermic patients with LFT ≥ 60 minutes. The primary outcome was a favourable neurological outcome (cerebral performance categories 1-2). Multivariable logistic regression analyses were performed to assess the factors associated with a favourable neurological outcome.

Results: In total, 708 patients met the inclusion criteria, with favourable neurological outcomes at hospital discharge in 71 cases (10.0%). Age, shockable rhythm on hospital arrival, signs of life (SOLs) on hospital arrival, and transient return of spontaneous circulation (ROSC) were significantly associated with a favourable neurological outcome.

Conclusions: Approximately 10% of OHCA patients who underwent ECPR with LFT ≥ 60 minutes had favourable neurological outcomes. ECPR for non-hypothermic OHCA patients might be considered even with prolonged LFT based on age, shockable rhythm on hospital arrival, SOLs on hospital arrival, and presence of transient ROSC before ECMO initiation.

Keywords: extracorporeal cardiopulmonary resuscitation; low-flow duration; out-of-hospital cardiac arrest; signs of life; transient return of spontaneous circulation.