Appointed Surgery Scheduling Under Uncertain Surgery Duration

Optimizing surgical scheduling can help to alleviate the contradiction between limited medical resources of hospital and increasing demand.The uncertain surgical duration is one of the key factors influencing surgical scheduling.On the one hand,the duration of the operation will vary with the accumulation of experience in the medical team and the deterioration of the patient’s condition.On the other hand,the uncertainty of the basic duration of the patient’s operation will also have a significant impact on the surgical scheduling strategy.Simultaneously,in order to ensure that patients complete the operation in time,it is necessary to assigned the corresponding time window constraints for each operation.For this reason,the paper investigates the surgical scheduling with various service time constraints including the uncertain basic processing time,learning effect and deterioration effect.Furthermore,the time window constraints in the patient’s operation is considered.Firstly,from the perspective of surgical schedules problems with uncertain operation duration,a scheduling model where the operation duration was likelihood ratio ordered was built up.The learning effect and deteriorating effect in operation duration were considered.The model aimed to achieve the minimum expected completion time of all.the surgry.The results show that the optimal solution can be obtained as long as the surgry are processed according to the non-decreasing order of the expected normal operation duration.Finally,a set of numerical experiments were presented to simulate the process of surgical schedules,proving that the proposed scheduling model could shorten the completion time effectively.In the finite horizon,from the perspective of hospital operation,a surgical scheduling model with time windows and uncertain surgery durations which follow the normal distribution was built up.We assumed that strategic decisions assigned a specialty to each Operating Room(OR)day and dealt with decisions that determined block duration,time windows and sequence in each OR each day with the objective of minimizing the sum of expected lateness,earliness and time windows costs.The result show that the objective is optimal when the surgeries were performed according to the smallest-variance-first-rule(SV)and block duration as well as time windows were assigned according to the given multinomial.