Economic and workload impact of therapeutic interchange of inhaler medications and nebulizer solutions

To examine the financial impact of automatic formulary substitution of nebulization solutions for pressurized metered dose inhalers and dry powder inhalers and the effect of the automatic substitution initiative on respiratory care practitioner (RCP) workload at a community hospital.

A retrospective observational study was conducted in a 326-bed nonacademic community hospital. Adult patients who received respiratory medications and had an inpatient stay, were admitted for observation, or had an emergency room visit from December 2016 through February 2017 (the control group) or from December 2017 through February 2018 (the study group) were included in the analysis. The primary outcomes were the cost of respiratory medications per hospital stay and the number of RCP visits per hospital stay. The secondary outcome was the cost of wasted doses per hospital stay.

A total of 3,766 patients were included in the study: 2,030 in the study group and 1,736 in the control group. The mean cost of respiratory medications per hospital stay was significantly lower in the study group vs the control group ($13.29 vs $36.48, P < 0.001). The mean number of RCP visits per hospital stay was also statistically lower in the study group vs the control group (11.6 vs 12.9, P = 0.04). The mean cost of wasted doses was significantly lower in study group vs the control group ($0.25 vs $22.91, P < 0.001).

Automatic formulary substitution of nebulization solutions for inhaler medications significantly decreased medication costs without increasing the average number of RCP visits per hospital stay.