Impact of an antimicrobial utilization program on antimicrobial use at a large teaching hospital: A randomized controlled trial

BACKGROUND: Multidisciplinary antimicrobial utilization teams (AUT) have been proposed as a mechanism for improving antimicrobial use, but data on their efficacy remain limited. OBJECTIVE: To determine the impact of an AUT on antimicrobial use at a teaching hospital. DESIGN: Randomized controlled intervention trial. SETTING: A 953-bed public university-affiliated urban teaching hospital. PATIENTS: Patients who were prescribed selected antimicrobial agents (piperacillin-tazobactam, levofloxacin, or vancomycin) by internal medicine ward teams. INTERVENTION: Twelve internal medicine teams were randomized monthly: 6 teams to intervention group (academic detailing by the AUT), and 6 teams to a control group given indication-based guidelines for prescription of broad spectrum antimicrobials (standard of care) during a 10-month study period. MEASUREMENTS: Proportion of appropriate empiric, definitive (therapeutic), and end antimicrobial (overall) usage. RESULTS: A total of 784 new prescriptions of piperacillin-tazobactam, levofloxacin, and vancomycin were reviewed. The proportion of appropriate antimicrobial prescriptions written by the intervention teams was significantly higher than prescribed by the control teams: 82% vs. 73% for empiric (RR=1.14, 95% CI 1.04–1.24), 82% vs. 43% for definitive (RR=1.89, 95% CI 1.53–2.33), and 94% vs. 70% for end antimicrobial usage (RR=1.34, 95% CI 1.25–1.43). In a multivariate analysis, teams that received feedback from the AUT alone (aRR=1.37, 95% CI 1.27–1.48) or from both the AUT and the ID consult service (aRR=2.28, 95% CI 1.64–3.19) were significantly more likely to prescribe end antimicrobial usage appropriately compared to control teams. CONCLUSIONS: A multidisciplinary AUT which provides feedback to prescribing physicians was an effective method in improving antimicrobial use