Lean principles and simulation optimization for emergency department layout design

Purpose - The purpose of this paper is to use lean principles and simulation optimization on solving a combined hospital emergency department (ED) layout design and staff assignment problem. Design/methodology/approach - This study is based on value stream mapping for the design and analysis of the ED. Subsequently, the authors investigate cellular manufacturing design, which addresses the decisions of continuous steps in a cell simultaneously and considers the optimal staff assignment. A simulation based on the case study is used for these methodologies. Simulation optimization is then used to optimize the staff assignments, minimize the waiting time and maximize the service level. Findings - The linear layout outperformed in both waiting time and service level. The patients' average waiting time is reduced from 78 to 38 minutes. The service level increased from 54.86 to 88.55 percent. Moreover, the number of nurses was reduced from nine to six. Research limitations/implications - First, the tests for model accuracy were performed using the actual arrival rate; however, seasonal variation should be reflected. Second, the staffing levels varied were not tracked. Third, the accuracy of individual patient treatment paths can be dynamic. Fourth, the 25 percent of delays in transferring a patient to an inpatient bed will be discussed in future studies. Practical implications - A practical case is adopted for empirical illustrations. Originality/value - The proposed methodology innovatively solved a practical application and the results are promising.