A high percentage of hospital admissions is due to surgical interventions. The operating theatre, which holds the operating rooms (ORs), is therefore one of the key resources in hospitals. The operating rooms are an expensive resource, but also generate most revenue. However, managing the operating theatre and finding an optimal OR schedule is complex due to the many factors that influence it. This research was conducted at Leiden University Medical Centre (LUMC), an academic teaching hospital in Leiden, the Netherlands. The LUMC uses a cyclic schedule that repeats every two weeks. In that schedule surgical specialties are assigned to whole days in an OR. The specialties can then schedule this day with surgeries. In the current planning of the OR complex of the LUMC, there is a regular shortage of capacity being perceived. Scheduling a surgery in an OR influences downstream facilities like the post anaestesia care unit (PACU), intensive care unit (ICU), and general patient wards. Currently, while scheduling the ORs, these downstream facilities are not always considered even though the capacity of these facilities can be limiting on scheduling surgeries.

Schedulers in the LUMC notice many cancellations of surgical patients due to capacity issues. Most often, they occur because there are no beds available at the ICU or patient wards. During the week, there is a large variation in bed occupancy due to the way elective surgeries are planned. Therefore, this research aims to find an OR schedule that minimises the variation in bed occupancy and maximises the OR utilisation.