Modeling the impact of changing patient flow processes in an emergency department: Insights from a computer simulation study

Abstract

We report on the use of discrete-event simulation modeling to support process improvements in a hospital emergency department (ED), namely the implementation of a split-flow process. Our partner hospital was effective in treating patients, but wait time and congestion in the ED created patient dissatisfaction, unsafe conditions and staff morale issues. The split-flow concept is an emerging approach to manage ED processes by splitting patient flow according to patient acuity and enabling parallel processing. We contrast the split-flow operational model to other types of ED triage. While early implementations of the split-flow concept have demonstrated significant improvements in patient wait times, a systematic evaluation of operational configurations is lacking.We created a discrete-event simulation model and established its face validity for Saint Vincent Hospital in Worcester, USA, a community-teaching, Level II Trauma Center. Seventeen scenarios were tested to estimate the likely impact of a split-flow process redesign, including staffing level changes and patient volume changes. The scenarios were compared in terms of Door-to-Doctor time and length-of-stay for different patient acuity levels.Findings from the study supported implementation of the split-flow improvements. Statistical analysis of data taken before and after the implementation indicate that waiting time measures were significantly improved and overall patient length-of-stay was reduced. To gauge the success of the current split-flow process at Saint Vincent we compare performance metrics from three different sources: benchmark metrics, hospital data prior to split-flow implementation, and performance metrics post implementation.