Implementation of a multi-disciplinary antimicrobial stewardship program in a tertiary hospital in Boyacá, Colombia: a quasi-experimental evaluation of prescription quality and antibiotic use.

BACKGROUND

Antimicrobial stewardship interventions are essential for optimizing antibiotic use and combating resistance. We implemented a multi-disciplinary, non-restrictive Antimicrobial Stewardship Program (ASP) at a tertiary hospital in Boyacá, Colombia.

OBJECTIVE

The aim of this study was to evaluate the effect of the ASP on antimicrobial consumption prescription patterns.

METHODS

A quasi-experimental study was used to compare antimicrobial prescriptions before (June-December 2023) and after (January-July 2024) ASP implementation. Adult inpatients receiving broad-spectrum antimicrobials for ≥48 h were included in the study. Prescription appropriateness and dose/schedule deviations were evaluated through prospective audit and feedback by a multi-disciplinary team. Consumption was measured using defined daily doses per 100 patient-days. A probit regression model was used to assess the association between prescriber type and prescription appropriateness. Confounding was addressed using a directed acyclic graph to determine the minimal adjustment set.

RESULTS

Out of 3845 prescriptions from 2491 patients, a significant improvement was observed in dosing accuracy and appropriateness of prescriptions after ASP implementation (P < 0.001). Use of amikacin and piperacillin/tazobactam decreased by 47.4% and 48.9%, respectively, while ceftriaxone use increased by 52.9%. The adjusted probit model showed that, compared with infectious disease specialists, orthopaedic surgeons were 48.7% (95% confidence interval [CI]: 36.0-61.4%) and general surgeons 33.9% (95% CI: 22.4-45.5%) less likely to issue appropriate prescriptions, after controlling for patient sex and infection type.

CONCLUSION

The ASP improved antimicrobial prescribing and reduced use of selected broad-spectrum antibiotics. Sustained improvements may require further efforts targeting surgical services and institutional integration.