A two-step approach to create and evaluate an optimization method for surgical instrument trays to reduce their environmental impact

Objective: This study combines Integer Linear Programming (ILP) and carbon footprint analysis based on the Life Cycle Assessment (LCA) method to reduce the carbon footprint of surgical instrument trays and their use.Materials and methods: A case study was carried out quantifying the instrument usage during the radical hysterectomy procedure. Using LCA we modelled the carbon footprint of the instrument trays, cradle to grave. The resulting carbon footprint data were used as input for an ILP model. The ILP model aims for an environmentally optimized composition of surgical instrument trays, without influencing patient safety, and optimizes compo-sition based on different utilization rates.Results: Instrument usage for the radical hysterectomy procedure was 54%. The LCA showed that with 99.5% of the total carbon footprint, the use phase in which the surgical trays are cleaned and sterilized is the biggest contributor. The ILP showed that for the radical hysterectomy procedure, an annual reduction in emission of 230 kgCO2-eq (46%) can be achieved by optimizing the trays. Discussion: The results of this study show that the carbon footprint of surgical instrument trays is mainly impacted by the surgical tray size and number of used trays. Implementing the proposed method and environmentally optimizing surgical trays requires a multidisciplinary team, including surgeons, OR scrub nurses and those who have knowledge of LCA and ILP. Conclusion: A combined method of ILP and LCA is suitable to provide insights on how to optimize surgical instrument trays with the objective to reduce the carbon footprint of these trays.