A hybrid simulation framework for reducing emergency patient boarding

The increasing proportion of patients requiring hospital admission after being diagnosed in an Emergency Department (ED) directly affects the number of boarding patients, as well as the delay in transferring them to an inpatient bed. Holding patients in the ED due to the unavailability of inpatient beds (patient boarding) is a major driver of ED overcrowding, and it also affects patient throughput times in the ED and has a negative impact on those waiting in ED corridors for several hours. While the primary reported cause of this phenomenon is the reduction in inpatient beds due to hospital budget restrictions, recent studies suggest that bed management strategies also play a significant role. To this hand, a hybrid simulation model has been developed to represent the dynamics of the entire hospital system, integrating both emergency and elective patient flows. The model serves to design an optimization framework aimed at identifying the most effective configuration for the bed management algorithm. The proposed hybrid simulation–optimization approach is applied to a real-world case study to evaluate the impact of optimized bed management strategies. An extensive set of scenarios analysis is also presented to compare alternative organizational changes, using a set of indicators that can evaluate the performance from the viewpoints of different stakeholders, such as emergency patient boarding time and volume, elective patients delays and blocking, and inpatient hospital ward utilization rates. The results highlight that, by employing specific strategies, the number of boarding patients and the boarding waiting times can be reduced, even without increasing the number of inpatient beds or negatively affecting elective patient flow.