Multi-criteria optimization scheduling of surgical units: a case study at AOU-Policlinico Umberto I

Nowadays, Operating Rooms (ORs) scheduling and planning represent one of the most challenging aspects in healthcare systems management. In particular, one of the main concern is doubtless the under-use of the surgery rooms, that one can tackle by modelling different management decision aspects. The number of ORs available in the operating theatre and their daily opening time, the ideal OR Utilization Rate (UR) that the hospital aims to fulfil, the possibility to transfer patients between different surgical units (SUs) are just some of them. Taking into account these management and economic factors, we develop a multi-criteria mixed integer linear optimization model that effectively contributes to the scheduling of surgeries. The model is practically relevant and addresses the particular case of the Azienda Ospedaliera-Universitaria Policlinico Umberto I of Rome. The problem is formulated according to an open scheduling strategy, which allows to schedule a weekly list of surgeries by determining the day, time, and operating room needed. Extensive experiments are carried on real data collected during twelve weeks in two SUs and four ORs. The impact of several policies of opening times on the hospital Key Performance Indicators is also tested and we further stress the model introducing randomly generated data in order to take into account surgery priorities. Results demonstrate the significant contribution of using a mathematical model to improve ORs utilization.