Emergency Department Length of Stay and in-Hospital Mortality of Non-Traumatic Patients in a University Hospital

Objective: To assess the emergency department length of stay (EDLOS) and mortality in each Emergency Severity Index (ESI) triage level. In addition to identifying the cut-off point of EDLOS to predict 72-hour in-hospital mortality among adult non-traumatic patients in the ED of a university hospital.Material and Methods: A cross-sectional study was conducted by retrieving patient data from the hospital information system; from January 1, 2014, to December 31, 2018. Patient characteristics, EDLOS, and in-hospital mortality rates were analyzed using the R program. The cut-off values of EDLOS, via the area under the curve for the best prediction of 72-hour in-hospital mortality in patients at different ESI levels, were analyzed by multivariate analysis. Statistical significance was defined as a p-value of ≤0.05.Results: Data from 71,247 patients with 123,356 visits were enrolled. EDLOS significantly decreased across ESI levels and the in-hospital mortality rates were highest in ESI 1, followed by ESI 2 and ESI 3. The predictive ability of EDLOS was the highest for ESI 4, followed by ESI 3. The cut-off point of EDLOS at 3.58 hours showed the best sensitivity, which was a significant risk factor for mortality after adjusting for other significant variables. An EDLOS longer than 4 hours was a significant factor for poor survival in patients with ESI 2 and ESI 3.Conclusion: A practical cut-off point of 4 hours EDLOS can be used to predict 72-hour in-hospital mortality. Healthcare providers in the ED should consider EDLOS as a safety indicator for quality assurance.