Introduction: This article proposes a method which could improve the performance of an Emergency Department (ED) in a large hospital in Tehran, where the long waiting times cause patients’ and ED staff ’s dissatisfaction. ED is considered as a bottleneck in hospitals. To reduce long waiting time and improve patient satisfaction, application of system improvement methods is required.
Methods: Using discrete- event simulation, it first models patient flow and identifies bottlenecks. In simulation model, patient arrival is assumed to be non-homogenous and operations of medical tests are detailed and consequently patient queues and virtual specimen queues can be considered separately. The analytic hierarchy process (AHP) was used to specify weights for each criterion and PROMETHEE to rank scenarios.
Results: Based on simulation results and important criteria, what-if scenarios were designed to evaluate system reactions. Using this method, 10 scenarios were designed. Implementing the best scenario would reduce waiting time by approximately 6%.
Conclustion: Considering ED overcrowding, simulation is used to reflect current situation. Based on the simulation reports, what-if scenarios were used to design scenarios which could improve ED performance. Multi criteria decision making method was used to find the best scenario based on criteria like waiting time, utilization, leave with own responsibility (LWOR) and cost.