142 - Frequency of Short-course Empiric Antibiotic Use as an Antimicrobial Stewardship Metric

Background: Antimicrobial stewardship metrics that provide actionable guidance are needed to support efforts to improve hospital use of antibiotics. Antibiotics such as vancomycin and piperacillin/tazobactam are common empiric agents used frequently when the infectious process remains unknown. Thus short, incomplete courses of therapy are used more frequently for such agents. We aimed to evaluate the variability in short courses of vancomycin and piperacillin/tazobactam use across U.S. hospitals.Figure. Frequency of Short-Course Antibiotic Prescribing Across Hospitals


Methods: We performed a cross-sectional study among U.S. hospitals that contributed inpatient pharmacy data to the Vizient clinical database in 2016.  We identified vancomycin and piperacillin-tazobactam courses initiated within the 48 hours of admission, measured as days of therapy received. We calculated the percent of patients that received 1, 2, 3, 4 or >4 days of therapy at each facility to describe short course empiric therapy use. To describe the variability across facilities, we then assessed the median, interquartile range (IQR), and total range of that percentage.

Results: We identified 145 hospitals representing approximately 3.7 million patient encounters for inclusion in this study. Within 48 hours of admission, 13.9% of encounters received vancomycin, 7.7% piperacillin/tazobactam, and 4.6% received both. The figure demonstrates the variability in the frequency of short course antibiotic use across hospitals; boxes indicate the IQR with the transecting line representing the median and whiskers representing the full range. The proportion of patients that received one day of therapy varied most across hospitals, with vancomycin ranging from 0-100%.  In contrast, the frequency of patients that received greater than four days of therapy varied considerably less across hospitals; 0-33% for vancomycin.

Conclusion: The variability in use of short course empiric therapies suggests that use for non-infectious processes or infections not appropriately treated by these agents varies greatly across facilities. Measuring short course use for common empiric agents may serve as an important antimicrobial stewardship metric. Such a metric could inform antimicrobial stewardship efforts to reduce unnecessary initiation of empiric antimicrobial therapy.