Background: An inpatient antimicrobial stewardship program is vital for judicious antimicrobial use. We began a hospital-wide, postprescription review with feedback (PPRF) in 2014; the present study evaluated its impact on antimicrobial consumption and clinical outcomes over 4 years.
Methods: Once-weekly PPRF for carbapenems and piperacillin/tazobactam was implemented. We tracked the data on each antimicrobial use as days of therapy (DOT) per 1000 patient-days (PD). Changes in the incidence of drug-resistant organisms, in-hospital mortality, and length of hospital stay per month were analyzed by an interrupted time series.
Results: Carbapenem use continued to decline in the preintervention and intervention periods (-0.73 and -0.003 DOT/1000 PD, respectively), and although monthly average use remained low in the intervention period (8.3 DOT/1000 PD), more importantly, the postintervention change in the slope diminished significantly. Piperacillin/tazobactam use showed a steeper decline in the intervention period, but the change in the slope was not statistically significant (change in slope: -0.20 DOT/1000 PD per month [P = .16]). Postintervention use of narrower-spectrum antimicrobials including ampicillin/sulbactam (change in slope: +0.58 DOT/1000 PD per month [P < .001]) increased. The antimicrobial cost and the monthly average length of hospital stay also declined (-37.4 USD/1000 PD per month [P < .001] and -0.04 days per month [P < .001], respectively), whereas few postintervention changes in the incidence of drug-resistant organisms were observed.
Conclusions: In our study, the 4-year PPRF for broad-spectrum antimicrobials coincided with a reduction in the use of targeted antimicrobials and resulted in an improvement in 1 patient-centered outcome, thus conferring the additional benefit of reducing expenditures for antimicrobials.
Keywords: antimicrobial stewardship program; broad-spectrum antimicrobials; postprescription review and feedback.