Can the prehospital National Early Warning Score 2 identify patients at risk of in-hospital early mortality? A prospective, multicenter cohort study

Abstract

Background: The National Early Warning Score 2 (NEWS2) scores can help identify clinical deterioration.

Objective: To assess the predictive capacity of the NEWS2 at prehospital level for the detection of early mortality in the hospital.

Methods: Prospective multicenter cohort study, in which we compiled a database of observed vital signs between March 1, 2018 and May 30, 2019. We collected demographic data, vital signs (respiration rate, oxygen saturation, supplemental oxygen, temperature, systolic blood pressure, heart rate and level of consciousness), prehospital diagnosis and hospital mortality data. We calculated the AUROC of the NEWS2 for early mortality.

Results: We included a total of 2335 participants. Median age was 69 years (IQR 54-81 years). The AUC for mortality within one day was 0.862 (95%CI:0.78-0.93), within two days 0.885 (95%CI:0.84-0.92) and within seven days 0.835 (95%CI:0.79-0.87) (in all cases, p<0.001).

Conclusions: The NEWS2 performed at prehospital level is a bedside tool for predicting early hospital mortality.

Keywords: Ambulance; Clinical decision; Early warning; Mortality; Prehospital care; Prognosis; Vital signs.