The Impact of a Best Practice Advisory on Inpatient Prescribing of Piperacillin-Tazobactam

Background: Antibiotic “time outs” have been identified as a way to decrease inappropriate use of antibiotics in hospitals.1 The University of Vermont Medical Center created a best-practice advisory (BPA) to alert clinicians to review piperacillin-tazobactam prescriptions after 72 hours (Fig. 1). Data examining the use of a BPA as a method to prompt clinicians to perform an antibiotic “time out” are limited. Objective: The purpose of our retrospective study was to evaluate the effectiveness of the BPA on the rate of piperacillin-tazobactam prescribing as measured by defined daily dose per 1,000 patient days (DDD). Methods: The BPA was integrated into the electronic health record and designed to activate once piperacillin-tazobactam has been prescribed for ≥72 hours. Under approval of the University of Vermont’s Institutional Review Board, administered data for piperacillin-tazobactam and 3 control antibiotics (cefazolin, ceftriaxone, and meropenem) were collected for 1 year prior to and 1 year following the launch of the BPA. Administered data were converted to DDD, and an interrupted time-series analysis was performed to evaluate for changes in antibiotic use. Results: The data included 7,094 patients in the preintervention group and 6,661 patients in the postintervention group. The BPA fired 1,478 times. The prescribing rate of piperacillin-tazobactam 1 year prior to the BPA was 32.34 DDD and decreased every month both before (−1.22 DDD) and after (−0.27 DDD) the BPA initiation, with no significant difference in prescribing trends (P = .10). Meropenem prescribing in the BPA era increased each month compared to the pre-BPA period (1.16 DDD; P = 0.02), whereas cefazolin use (P = .93) and ceftriaxone (P = .09) use did not significantly change. Conclusions: The data show that piperacillin-tazobactam utilization at our institution is decreasing. Considering that this trend started prior to the launch of the BPA and that rate of decline remained unchanged post-BPA, we conclude that the BPA did not further impact our piperacillin-tazobactam consumption. It is possible that other factors influencing prescribing account for the observed decline, including an institution-wide educational campaign regarding the appropriate use of broad-spectrum antibiotics that was initiated in the months prior to the BPA. The reason for the significant rise in meropenem post-BPA is unclear. This may be unrelated to the BPA; however, it requires further investigation.1. Core elements of hospital antibiotic stewardship programs. Centers for Disease Control and Prevention website. https://www.cdc.gov/antibioticuse/healthcare/implementation/core-elements.html. Updated July 19, 2019. Accessed October 6, 2019.Funding: NoneDisclosures: None