Impact of an Antimicrobial Stewardship Program on the Use of Carbapenems in a Tertiary Women's and Children's Hospital, Singapore

Objectives Antimicrobial stewardship programs (ASPs) promote the judicious use of antimicrobials by limiting inappropriate use. This article evaluates the impact of a prospective‐audit‐and‐feedback ASP implementation on the appropriate utilization of carbapenems in a tertiary pediatrics and obstetrics/gynecology hospital in Singapore (KKH) after the establishment of an ASP in July 2011. Methods This was a prospective, single‐center, pre‐post intervention study designed to analyze the appropriate prescribing of carbapenems pre‐ASP (October 2009 to June 2011) and post‐ASP (July 2011 to December 2013). Utilization of carbapenems was evaluated by daily defined doses (DDDs), days of therapy (DOTs), prescriptions, as well as cost per 100 patient‐days pre‐ASP and post‐ASP using a segmented regression of interrupted time series analysis. Results Of 404 prescriptions for carbapenems reviewed post‐ASP, 70.3% were appropriate compared with those prescribed pre‐ASP (55.9%; p=0.027). Reasons for inappropriate prescribing included inappropriate choice (36.1%) and duration (31.3%). A total of 61.2% of the interventions (213 of 348) were accepted. For pediatrics, there was a significant decrease in DDDs per 100 patient‐days by 55.6% from a baseline of 0.9–0.4 (p=0.013) post‐ASP and a reduction in DOTs per 100 patient‐days by 46.7% from a baseline of 1.5–0.8 (p=0.06) post‐ASP without significant changes in prescription rates. Pediatrics utilization cost increased from a pre‐ASP mean of $175 per 100 patient‐days to a peak of $238 (p