Clinical deterioration and death among patients with acute stroke are often preceded by detrimental changes in physiological parameters. Systematic and effective tools to identify patients at risk of deterioration early enough to intervene are therefore needed. The aim of the study was to investigate whether the aggregate weighted track and trigger system early warning score (EWS) can be used as a simple observational tool to identify patients at risk and predict mortality in a population of patients with acute stroke. Patients admitted with acute stroke at the Copenhagen University Hospital, Nordsjaellands Hospital, Denmark, from May to September 2012 were enrolled in a retrospective cohort study (n = 274). Vital signs were measured immediately after admission and consistently during the hospitalization period. Based on the vital signs, a single composite EWS was calculated. Death within 30 days was used as outcome. Area under the receiver operating characteristics curve (AUROC) and a Kaplan-Meier curve were computed to examine the prognostic validity of EWS. A total of 24 patients (8.8%) died within 30 days. The prognostic performance was high for both the EWS at admission (AUROC 0.856; 95% CI 0.760-0.951; P-value < 0.001) and the maximal EWS measured (AUROC 0.949; 95% CI 0.919-0.980; P-value < 0.001). Mortality rates were lowest for admission EWS 0-1 (2%) and highest for admission EWS ≥ 5 (63%).
Early warning score is a simple and valid tool for identifying patients at risk of dying after acute stroke. Readily available physiological parameters are converted to a single score, which can guide both nurses and physicians in clinical decision making and resource allocation.