Impact of a prospective audit and feedback antimicrobial stewardship programme on carbapenem consumption: a quasi-experimental study (IPANEMA study)

OBJECTIVES: To test the hypothesis that a prospective audit and feedback (PAF) intervention combined with electronic tools will reduce carbapenem use without negatively affecting patient outcomes. METHODS: A quasi-experimental, pre-intervention and intervention study was performed conducted in the urology department of a university hospital. The intervention involved implementing a PAF within an antimicrobial stewardship programme with the aid of an electronic tool. The primary outcome was carbapenem use, assessed by DDD/100 patient-days (PD). Secondary outcomes included evaluating the effect of the intervention on overall antibiotic use measured by DDD/100 PD and days of therapy (DOT)/100 PD, as well as patient safety. The chi-squared test or t-test was used, and the Poisson model was employed to assess the association between the intervention and outcomes. RESULTS: A 9% decrease in carbapenem DDD/100 PD was observed during the intervention period (IR = 0.91; 95% CI = 0.85-0.97, P = 0.007). The proportion of patients who received carbapenem treatment dropped from 17.8% to 16.5% [incidence ratio (IR) = 0.95; 95% CI = 0.86-2.05, P = 0.31]. Carbapenem DOT/100 PD decreased from 12.4 to 11.0 (IR = 0.89; 95% CI = 0.83-0.94, P < 0.001). Overall antibiotic DDD/100 PD decreased by 3% (IR = 0.97; 95% CI = 0.94-0.99, P = 0.001) and DOT/100 PD by 7% (IR = 0.93; 95% CI = 0.91-0.95, P < 0.001). The incidence of infections caused by carbapenemase-producing microorganisms, Enterococcus faecium bacteraemia and Clostridioides difficile-associated diarrhoea episodes was similar in the pre-intervention and intervention periods. ESBL incidence rate decreased, but the differences were not statistically significant (3.94/1000 PD versus 2.88/1000 PD, P = 0.111). Length of hospital stay, in-hospital all-cause mortality, and 30 day readmission incidence remained unchanged. CONCLUSIONS: The implementation of PAF combined with an electronic tool was an effective and safe intervention for reducing carbapenem use.