Two-stage robust optimization problem for operating room planning
The process of operating room planning includes the scheduling of disciplines, patients, surgeons, materials and the availability of the wards. An efficient planning is one of the conditions to keep the patients satisfied and to comply with the principles of the disciplines, patients, surgeons, materials, and wards. The operating room planning is divided into two sub problems. The first problem is the Discipline Assignment (DA) problem in which disciplines are assigned to blocks and the second problem is the Surgery Assignment (SA) problem which assigns surgeries (equivalently patients) to one of the blocks with the corresponding discipline. In this thesis, for each of the sub problems a two-stage robust program is proposed based on the principles of the operating room planning of a top clinical hospital in the Netherlands. The current planning for operating rooms is inefficient and causes problems like overload of wards, overtime of personnel, underutilization of operating rooms while the patient waiting lists are long. In the SA problem the variability in the number of patients at a ward during a planning cycle is considered in order to decrease the workload at the ward. A column-and-constraint generation approach is used to solve the two-stage robust optimization problems. The proposed DA schedule reduces the impact of the emergency surgeries on the elective surgeries. The number of blocks allocated to the disciplines are divided over the two locations of the hospital Furthermore, the solution method of the SA problem decreases the variability in the ward substantially. Moreover, less patients can be scheduled due to the lack of available beds. This result contributes to a balanced workload. In conclusion, the proposed method improves the efficiency of the operating room planning.