Audit of the prescription of antimicrobials using the four moments of decision tool in a university hospital

BACKGROUND: Antimicrobial resistance is a growing global threat driven by inappropriate antimicrobial use. The Four Moments of Antibiotic Decision Making is a stewardship framework that promotes rational antibiotic use. This study applied this framework to audit antimicrobial prescribing, assess adherence, and measure antimicrobial use. METHODS: We conducted a retrospective, cross-sectional audit of patients who received systemic antimicrobials between October and November 2023. The four audited moments included: (1) indication, suspected site, and clinical evidence of infection; (2) antimicrobial selection and culture collection; (3) reassessment between days 3 and 5 based on clinical response and culture results; and (4) treatment duration. Antimicrobial consumption was measured using days of therapy (DOT), length of therapy (LOT) and the WHO AWaRe classification. RESULTS: A total of 228 patients (53.5% male; mean age 57 years) received 304 antimicrobial treatments, including 129 intensive care units (ICU) admissions. 75.0% were fully adherent to all Four Moments. Adherence rates across moments 1 to 4 were 97%, 88.8%, 89.3%, and 87.1%, respectively. In moment 2, cultures were indicated in 201 treatments but not requested in 15% of cases. Vancomycin was the most prolonged treatment, followed by ceftriaxone, piperacillin-tazobactam, and meropenem. Antimicrobial use was higher in ICUs, with DOT and LOT reaching 739 and 706 per 1,000 patient-days, respectively, compared with 496 and 319 in the wards. Most antimicrobial consumption corresponded to WHO AWaRe Watch antibiotics. CONCLUSIONS: Adherence to stewardship principles was high, although opportunities for improvement remain, particularly regarding culture collection and treatment duration optimization.