Neurologically intact survival after cardiac arrest is possible even after prolonged resuscitation efforts. However, the factors associated with good neurologic outcome in these patients remain unknown. This study identifies predictors associated with good neurologic outcome after resuscitation beyond 30 min in out-of-hospital cardiac arrest (OHCA) patients treated with targeted temperature management (TTM). This multicenter, registry-based, retrospective cohort study conducted in 24 hospitals across South Korea between 2007 and 2012 includes adult (≥18 years) non-traumatic OHCA patients with prolonged (>30 min) downtime who underwent TTM treatment. Good neurologic outcomes were defined as cerebral performance category scores of ≤2. Of the 930 comatose adult cardiac arrest patients treated with TTM, 423 patients with prolonged downtime were included. A total of 76 (18.0%) had good neurologic outcome. Multivariable analysis reveal that age <65 years (OR 7.91, 95% CI 3.18-19.68), initial shockable rhythm (OR 6.31, 95% CI 3.40-11.74), and witnessed arrest (OR 3.81, 95% CI 1.73-8.45) are associated with good neurologic outcome. The sensitivity and specificity for good neurologic outcome in patients with age <65 years, shockable rhythm, and witnessed arrest are 90.8% and 41.2, 67.6 and 79.5%, and 81.6 and 41.2%, respectively. In prolonged cardiac arrest patients, initial shockable rhythm, age <65 years, or witnessed arrest are predictors for neurologic intact survival.
Keywords: Out-of-hospital cardiac arrest; Outcomes; Resuscitation; Targeted temperature management.