Derivation of a cardiac arrest prediction model using ward vital signs*

Abstract

Objective Rapid response team (RRT) activation criteria were created using expert opinion and have demonstrated variable accuracy in previous studies. We developed a cardiac arrest risk triage (CART) score to predict cardiac arrest (CA) and compared it to the Modified Early Warning Score (MEWS), a commonly cited RRT activation criterion. Design A retrospective cohort study. Setting An academic medical center in the United States. Patients All patients hospitalized from November 2008 to January 2011 who had documented ward vital signs were included in the study. These patients were divided into three cohorts: patients who suffered a CA on the wards, patients who had a ward to intensive care unit (ICU) transfer, and patients who had neither of these outcomes (controls). Interventions None. Measurements and Main Results Ward vital signs from admission until discharge, ICU transfer, or ward CA were extracted from the medical record. Multivariate logistic regression was used to predict CA, and the CART score was calculated using the regression coefficients. The model was validated by comparing its accuracy for detecting ICU transfer to the MEWS. Each patient’s maximum score prior to CA, ICU transfer, or discharge was used to compare the areas under the receiver operating characteristic curves (AUC) between the two models. Eighty-eight CA patients, 2820 ICU transfers, and 44519 controls were included in the study. The CART score more accurately predicted CA than the MEWS (AUC 0.84 vs. 0.76;P=0.001). At a specificity of 89.9%, the CART score had a sensitivity of 53.4% compared to 47.7% for the MEWS. The CART score also predicted ICU transfer better than the MEWS (AUC 0.71 vs. 0.67;P<0.001). Conclusions The CART score is simpler and more accurately detected CA and ICU transfer than the MEWS. Implementation of this tool may decrease RRT resource utilization and provide a better opportunity to improve patient outcomes than the MEWS.

Risk Stratification of Hospitalized Patients on the Wards

“…30 Our group published an aggregate weighted system known as the Cardiac Arrest Risk Triage (CART) score ( Table 4 ). 31 The CART score was derived using logistic regression to detect in-hospital cardiac arrest and was validated for detecting ward-to-ICU transfers. In that study, the CART score outperformed the MEWS for detecting both cardiac arrest (AUC, 0.84 vs 0.76; P 5 .001) and ICU transfer (AUC, 0.71 vs 0.67; P , .001).…”

Using Electronic Health Record Data to Develop and Validate a Prediction Model for Adverse Outcomes on the Wards

“…Second, these results were recalculated by using whether a cardiac arrest or ICU transfer occurred within 24 hours of each measurement time as the definition of having the event of interest. Both of these definitions have been used in previous studies investigating the accuracy of ward risk scores (3,8,9,17,18).…”

Frailty Assessment in Acute Care

“…Advanced age is independently associated with death and cardiac arrest, and use of age further improves predictive accuracy of many of the physiology based risk models (117)(118)(119)(120)(121)(122).…”