An mathematical model for surgery scheduling with considering Intensive Care Unit capacity constraint and multiple treatment routes

Scheduling and sequencing operations, as a decision making process, plays an integral role in most manufacturing and producing systems as well as most services environments. Scheduling is especially important in the field of healthcare. The proper scheduling of health wards in a hospital can lead to the optimum use of resources and reduce the cost of staff, overtimes of surgeons, nurses, anesthesiologists and so forth. Along with these achievements, the proper scheduling with the reduction of the waiting time of patients for the reception of services and accelerating the provision of services to emergency patients can upgrade the level of service provision. In this research, the problem of planning and scheduling of the operating room in the heart surgery department is examined. This scheduling is done due to the capacity constraint of the intensive care unit. A very important point in this study is that there are multiple treatment routes for treating patients. In this study first, the pathway for treating patients is estimated by a multinomial logistic regression model. Then the planning and scheduling of patients is done using a mixed integer mathematical model. The goal of this scheduling is to minimize the total treatment time, length of stay and waiting time of patients. In order to measure the effectiveness of the proposed models, the data and processes of the heart center of Tehran have been used.