Capacity Allocation for Emergency Surgical Scheduling with Multiple Priority Levels

Abstract

Emergency surgeries are serviced by three main forms of capacity: dedicated operating room time reserved for emergency surgeries, alternative (on call) capacity, and lastly, canceling of elective surgeries. The objective of this research is to model capacity implications of meeting wait time targets for multiple priority levels in the context of emergency surgeries. Initial attempts to solve the capacity evaluation problem were made using a non-linear optimisation model, however, this model was intractable. A simulation model was then used to examine the trade-off between additional dedicated operating room capacity (and consequent idle capacity) versus increased re-scheduling of elective surgeries while keeping reserved time for emergency surgeries low. Considered performance measures include utilization of operating room time, elective re-scheduling, and wait times by priority class. Finally, the instantaneous utilization of different types of downstream beds is determined to aid in capacity planning. The greatest number of patients seen within their respective wait time targets is achieved by a combination of additional on call capacity and a variation of the rule allowing low priority patients to utilize on call capacity. This also maintains lower cancelations of elective surgeries than the current situation. Although simulation does not provide an optimum solution it enables a comparison of different scenarios. This simulation model can determine appropriate capacity levels for servicing emergency patients of different priorities with different wait time targets.