A validated prediction tool for initial survivors of in-hospital cardiac arrest

Abstract

Background: Accurate estimation of favorable neurological survival after in-hospital cardiac arrest could provide critical information for physicians, patients, and families.

Methods: Within the Get With the Guidelines-Resuscitation registry, we identified 42,957 patients from 551 hospitals admitted between January 2000 and October 2009 who were successfully resuscitated from an in-hospital cardiac arrest. A simple prediction tool for favorable neurological survival in patients successfully resuscitated from an in-hospital cardiac arrest was developed using multivariate logistic regression, with two-thirds of the sample randomly selected as the derivation cohort and one-third as the validation cohort. Favorable neurological status was defined as the absence of severe neurological deficits (cerebral performance category score of ≤2).

Results: Rates of favorable neurological survival were similar in the derivation cohort (7052 patients [24.6%]) and validation cohort (3510 patients [24.5%]). Eleven variables were associated with favorable neurological survival: younger age, initial cardiac arrest rhythm of ventricular fibrillation or pulseless ventricular tachycardia with a defibrillation time of 2 minutes or less, baseline neurological status without disability, arrest location in a monitored unit, shorter duration of resuscitation, and absence of mechanical ventilation, renal insufficiency, hepatic insufficiency, sepsis, malignant disease, and hypotension prior to the arrest. The model had excellent discrimination (C statistic of 0.80 for both the derivation and validation cohorts) and calibration. The prediction tool demonstrated the ability to identify patients across a wide range of rates of favorable neurological survival: patients in the top decile had a 70.7% probability of this outcome, whereas patients in the bottom decile had a 2.8% probability.

Conclusions: Among successfully resuscitated patients with an in-hospital cardiac arrest, a simple, bedside prediction tool provides robust estimates of the probability of favorable neurological survival. This tool permits accurate prognostication after cardiac arrest for physicians, patients, and families.

Figure 1. Comparison of Predicted vs. Observed Outcome Rate for the Validation Cohort

Each data point represents a decile of risk for the outcome of favorable neurological survival to discharge.

Figure 2. The Cardiac Arrest Survival Post-Resuscitation In-hospital (CASPRI) Score Card and Nomogram for Favorable Neurological Survival

For this in-hospital cardiac arrest risk score, points for each variable are determined and a summary score is obtained. The corresponding likelihood of surviving to hospital discharge without severe neurological disability is determined from the risk table or plot.