Reliability Constrained Ureteroscope Allocation Integrating Instrument Training and Local Carbon Footprints

Background: Flexible ureteroscope procurement must reconcile procedural reliability, expenditure, and environmental burden. Published comparisons support selective device use, but provide limited guidance on allocating a constrained reusable inventory. Methods: We developed a deterministic decision model spanning 27 weighted combinations of anatomical complexity, device wear, and handling exposure. Separate equations represented procedural interruption and repair. Six policies were compared using explicitly hypothetical costs and carbon inputs, an illustrative 8% reusable interruption ceiling, and 80% reusable capacity. Training was represented by an assumed log-odds reduction and examined against a null effect. Results: The reliability and capacity constrained policy cost USD 679.46 per procedure, generated 7.09 kg carbon dioxide equivalent, and produced 3.33 expected interruptions per 100 procedures. Conditional training reduced these values to USD 667.25, 6.99 kg, and 2.75 interruptions. Training ceased saving money above USD 32.22 per procedure. Environmental rankings reversed under alternative carbon assumptions. Conclusions: Explicit reliability constraints expose trade-offs concealed by cost minimisation. Training benefits and environmental preferences remain conditional modelling results requiring local measurement and prospective validation.