C‐GRApH: A Validated Scoring System for Early Stratification of Neurologic Outcome After Out‐of‐Hospital Cardiac Arrest Treated With Targeted Temperature Management

Abstract

BackgroundOut‐of‐hospital cardiac arrest (OHCA) results in significant morbidity and mortality, primarily from neurologic injury. Predicting neurologic outcome early post‐OHCA remains difficult in patients receiving targeted temperature management. Methods and ResultsRetrospective analysis was performed on consecutive OHCA patients receiving targeted temperature management (32–34°C) for 24 hours at a tertiary‐care center from 2008 to 2012 (development cohort, n=122). The primary outcome was favorable neurologic outcome at hospital discharge, defined as cerebral performance category 1 to 2 (poor 3–5). Patient demographics, pre‐OHCA diagnoses, and initial laboratory studies post‐resuscitation were compared between favorable and poor neurologic outcomes with multivariable logistic regression used to develop a simple scoring system (C‐GRApH). The C‐GRApH score ranges 0 to 5 using equally weighted variables: (C): coronary artery disease, known pre‐OHCA; (G): glucose ≥200 mg/dL; (R): rhythm of arrest not ventricular tachycardia/fibrillation; (A): age >45; (pH): arterial pH ≤7.0. A validation cohort (n=344) included subsequent patients from the initial site (n=72) and an external quaternary‐care health system (n=272) from 2012 to 2014. The c‐statistic for predicting neurologic outcome was 0.82 (0.74–0.90, P<0.001) in the development cohort and 0.81 (0.76–0.87, P<0.001) in the validation cohort. When subdivided by C‐GRApH score, similar rates of favorable neurologic outcome were seen in both cohorts, 70% each for low (0–1, n=60), 22% versus 19% for medium (2–3, n=307), and 0% versus 2% for high (4–5, n=99) C‐GRApH scores in the development and validation cohorts, respectively. ConclusionsC‐GRApH stratifies neurologic outcomes following OHCA in patients receiving targeted temperature management (32–34°C) using objective data available at hospital presentation, identifying patient subsets with disproportionally favorable (C‐GRApH ≤1) and poor (C‐GRApH ≥4) prognoses.

Keywords

• heart arrest
• hypothermia
• prognosis
• resuscitation
• targeted temperature management