Impact of Area-Under-the-Curve Monitoring for Vancomycin on Incidence of Acute Kidney Injury in Orthopedic Patients

Vancomycin is an antibiotic used regularly in hospitals across the world. The most concerning adverse effect of vancomycin is its documented effect on kidney function. This study examines the impact of two dosing strategies of vancomycin on patients’ kidney function at the University of Kentucky Albert B. Chandler Medical Center. It specifically focuses on patients on the orthopedic service because these patients traditionally receive higher doses of vancomycin for longer periods of time due to the severity of their infections, which puts them at an increased risk of vancomycin-induced nephrotoxicity compared to other patients. This study will serve as a precursor to a larger, hospital-wide study of vancomycin induced nephrotoxicity as the University of Kentucky Albert B. Chandler Medical Center recently changed its policy on dosing vancomycin from using the traditional trough-based dosing method to using area-under-the-curve (AUC) dosing in September 2017. This study compares patients on the orthopedic service who received longer durations of vancomycin therapy prior to the policy change with those receiving vancomycin after the policy change to determine the impact of the dosing strategies on patient outcomes, specifically acute kidney injury (AKI). While this study is limited in patient population due to the recent nature of the policy change, the results support other studies that associate higher vancomycin troughs with increased risk for nephrotoxicity. Results also support studies that have found that patients often achieve a therapeutic AUC while maintaining lower troughs than expected. While this study did not show a significant difference between incidence of minor kidney injury between the two study populations, there was a significant difference in the incidence of more severe kidney injury (RIFLE Criteria Injury and Failure) in the two study populations, indicating that AUC-guided dosing is potentially safer for patients and results in fewer incidents of severe AKI. The follow-up study will be used to validate these results in other patient populations, including those with critical illness and different comorbidities