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

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.

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.

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.

Adherence to stewardship principles was high, although opportunities for improvement remain, particularly regarding culture collection and treatment duration optimization.