Prediction protocol for neurological outcome for survivors of out-of-hospital cardiac arrest treated with targeted temperature management.

Abstract

To identify patients who can obtain the full benefit from targeted temperature management (TTM) after out-of-hospital cardiac arrest. We performed a retrospective observational study of comatose patients treated with TTM after an out-of-hospital cardiac arrest from January 2006 to February 2011. Neurological outcome was evaluated with the Glasgow-Pittsburgh Cerebral Performance category (CPC) at discharge and predictors were determined. Of 66 patients studied, 40 (60.6%) survived to neurologically intact discharge (CPC 1 or 2). According to multivariate analysis, predictors of good neurological outcome included arrest-to-first cardiopulmonary resuscitation attempt interval ≤5 min, ventricular fibrillation or ventricular tachycardia in the first monitored rhythm, absence of re-arrest before leaving the emergency department, arrest-to-return of spontaneous circulation interval ≤30 min and recovery of pupillary light reflex, which were identifiable in the emergency department. Based on this analysis, we developed a seven-point score (5-R score). If the score was ≥5, it predicted good neurological outcome with a sensitivity of 82.5% (95% confidence interval [CI], 67.2-92.7%) and specificity of 92.3% (95% CI, 74.9-99.1%). The negative predictive value of a score ≥4 was 100% (95% CI, 81.5-100%). Our prediction model was validated internally by a bootstrapping technique. The prediction protocol using the 5-R score was associated with good neurological outcome of patients treated with TTM. Therefore, it could be helpful in clinical decision making on whether to initiate cooling.