Justification of a therapeutic drug monitoring clinical pharmacist position

Purpose: There is a growing consensus that higher vancomycin doses that are currently used to treat severe infections is leading to increased risk for nephrotoxicity. Our goal was to provide justification for a clinical pharmacist FTE in the area of therapeutic drug monitoring (TDM) to reduce the risk for vancomycin nephrotoxicity.

Methods: In 2011 an increased incidence of vancomycin-associated nephrotoxicity was observed at our institution. As a result, we formed a multidisciplinary steering committee in order to discuss the problem and to identify potential solutions. The committee included representatives from pharmacy, infectious disease physicians, nursing, and hospital administration. Meetings were convened in order to discuss the literature as it relates to antibiotic nephrotoxicity and to review our processes for dosing and monitoring vancomycin and aminoglycosides. This led to recommendations to standardize several processes for dosing and monitoring, and to conduct a return on investment (ROI) analysis of a clinical pharmacist dedicated to therapeutic drug monitoring. The ROI required hiring a clinical pharmacist as a “temporary” position within the pharmacy budget, and quantifying their interventions to reduce risk factors for nephrotoxicity. The costs of adverse drug events were estimates based on current literature.

Results: During the two month period of time used to estimate the ROI, the pharmacist documented 190 interventions. There were 143 interventions related to vancomycin and 42 for aminoglycosides. An estimated 21 adverse drug events were prevented. Estimated cost savings were $48,737 and the cost of the FTE during the study period was $24,583, yielding an estimated ROI of $144,924 for the year. This data was shared with hospital administration and a permanent FTE was approved.

Conclusions: Concern about an increased incidence of vancomycin-associated nephrotoxicity led to an institutional strategy to reduce risk which included a proposal to hire a clinical pharmacist. Our ROI analysis justified this position.