A bi-criteria optimization model for medical device sterilization
- PDF / 603,373 Bytes
- 23 Pages / 439.37 x 666.142 pts Page_size
- 10 Downloads / 197 Views
A bi-criteria optimization model for medical device sterilization Onur Ozturk1 © Springer Science+Business Media, LLC, part of Springer Nature 2019
Abstract This paper proposes a scheduling model for the washing step of medical device sterilization. After use in a surgery, medical devices pass through several steps where the washing is usually a bottleneck. We study the cases of external and internal sterilization services to minimize two objectives: makespan and flow time of washing operations. First, we study internal sterilization services considering jobs can have different or unit sizes. For these two cases, we provide a mixed integer linear model and a dynamic programming model, and integrate these methods in an -constraint model. For the case of external services, first we develop a simultaneous (2, 2) approximation algorithm and then derive an algorithmic scheme to generate a partial 2-approximation of the Pareto set. Several numerical experiments are conducted to demonstrate the strength of proposed solution methods. Keywords Medical device sterilization · Bicriteria batch scheduling · Approximation · Heuristics · Dynamic programming · Mathematical modeling
1 Introduction In this study, we are interested in the problem of loading automatic washers whose origin lies in the medical device sterilization process. A sterilization service (internal or external) is intended to sterilize any medical device used in a surgical procedure. Once sterile, these devices can be reused in other surgeries. They are therefore called reusable medical devices (or shortly RMDs). In the case of an internal sterilization service of a hospital, RMDs used in different surgeries are sent to the service at different times within a day since surgeries start and end at different moments. In the case of an external service however, RMDs used in different surgeries are sent to sterilization altogether at the same time. The steps of the sterilization process are the same for both internal and external services: rinsing and washing, verification, conditioning, and finally, autoclaving. After all these steps, the RMDs are ready for reuse. Among these steps, the washing is usually a bottleneck for the whole process (Di Mascolo and Gouin 2013). The washing step is composed of
B 1
Onur Ozturk [email protected] Telfer School of Management, University of Ottawa, 55 Laurier Avenue East, Ottawa, ON K1N 6N5, Canada
123
Annals of Operations Research
automatic washers which execute the rinsing and washing of several RMD sets at the same time. Here, an RMD set refers to all RMDs used for the same surgery. Due to traceability reasons, all RMDs of an RMD set must be washed at the same time in a single washer, i.e., splitting RMD sets is not permitted. However, more than one RMD set can be washed at the same time in the same machine complying with the capacity of the washer. Thus, we model the washing step as a batch scheduling problem where RMDs are treated as jobs having different sizes and a fixed processing time, but also different re
Data Loading...
