Calculation of sterilization costs using T-DOC traceability software The T-DOC calculation method breaks down the
costs for each product into five categories: Usage, sterilization, washing, packing, and handling. The six fields (one for each cost category and a “Total” field) are filled in automatically on the basis of parameterized data in the software for each cost category and product category (figure 2).Zentr Steril 2010; 18 (F3): 75–85 3 ZENTRAL STERILISATION 18 / 2010 Fig. 2: “Products” window – “Price” tab Usage costs This category allows the amortization of the cost of surgical instrumentation to be taken into account. At the University Hospital of Rouen, these costs are attributed to the budgetary accounts of the surgical units, meaning that the calculation of usage costs is not applicable in some cases. A possible usage of this category in T-DOC concerns single-use material. Effectively, it is possible to attribute the price of all sterilizable single-use material that forms part of an instrument tray to each sterilization cycle. Sterilization costs This figure is calculated by sharing the cost of the sterilization cycle amongst the products making up the batch. Thus, these costs are attributed to each product in accordance with the volume it takes up in the sterilizer. The calculation is based on the determination of 3 parameters: – The cost of the sterilization cycle – The basket capacity of the sterilizer – The volume of each product expressed as a “sterilizer volume index” calculated as 1 divided by the number of baskets occupied by the product The sterilization costs for a product are thus calculated by T-DOC using the following formula: [Cost of sterilization cycle in sterilizer / basket capacity of sterilizer] / product sterilizer volume index Washing costs This figure is calculated in accordance with the same logic as that used for the sterilization costs. Packaging costs This figure is calculated on the basis of the type of packaging used for each product and the associated consumables. Handling costs This figure reflects the labor costs and is calculated on the basis of the following 2 parameters: The handling time (i.e. the amount of time taken by the sterilization personnel to process each piece of material) and the hourly labor rate for the personnel.Zentr Steril 2010; 18 (F3): 75–85 4 ZENTRAL STERILISATION 18 / 2010 Data collection Data relating to usage costs This data relates to the invoicing of single-use consumables that form part of instrumentation trays. This charging structure has been restricted to aluminum cups. All other consumables have been disregarded due to their low cost in relation to the amount of work required to bill them separately. Data relating to sterilization costs Determination of the average cost of a sterilization cycle: The costs of a sterilizer cycle are broken down as follows:
– Fluid costs: Electricity, water purified by reverse osmosis, and softened water used in 1 cycle – Costs of consumables: Sheets of crepe paper used to prevent the batch from getting wet (standard quantity of 20 sheets) – Investment costs: Annual amortization of sterilizers in relation to the number of cycles per year – Maintenance and qualification costs in relation to the number of cycles per year (except labor costs for Technical Services employees) Determination of sterilizer capacity: The total load volume is expressed in terms of standard baskets (30 x 30 x 60 cm/54 liters). Determination of sterilizer volume indices: This is done in two stages: The determination of the absolute volume of the basket and then the measurement of a correction factor explained in more detail below. The absolute volume for the uro-digestive unit was determined by measuring the 3 dimensions of each treated product. In the case of individually packaged items, the measurements comprise the size of the pouch or tray used plus one centimeter in height to take into account the required space for the steam to pass through. In more general terms, the goods must be arranged in a way that enables good steam penetration. The “useful” or “real” load volume is thus lower than the total load volume expressed as standard baskets (figure 3). Therefore, the use of the absolute product volume to calculate the volume indexes results in an underestimation of the costs of sterilization.