Estimating costs of anesthesia supplies for intraoperative infection control

Some costs for anesthesia supplies to reduce intraoperative infections depend on the procedure and duration of the case. For regular anesthesia supplies and medications, costs are linearly related to American Society of Anesthesiologists' Relative Value Guide units, known for nearly all cases in the United States of America. We hypothesized linear association between costs of infection control items and anesthesia units.

A prospective observational study of 38 surgical cases was performed. Usage of anesthesia infection control supplies was recorded: alcohol hand dispensers, microfiber cloths for machine disinfection, and disinfecting and cleaning caps for syringe tips, Luer connectors, and stopcocks. Cost per case was calculated using 2022 US dollar payments for those items.

Using least squares linear regression to associate the anesthesia units (base + time) with supply costs, in addition to intercept and linear slope, none of 5 potential extra non-linear terms were significant (all P ≥ .46). Further assessment showed lack of fit to a quadratic model. Pearson linear correlation coefficient between cost and units was 0.88. An example was created showing how to forecast annual infection control supply costs for anesthesia based on the linear model.

For purposes of predicting intraoperative anesthesia supplies to reduce bacterial transmission in the anesthesia workspace, a valid approach is to assume a linear association with the total anesthesia units, a predictor generally known for all anesthetics.