[Antimicrobial stewardship program in an Intensive Care Unit: A retrospective observational analysis of the results 15 months after its implementation].

Objective: We aim to evaluate the adherence rate to an Antimicrobial Stewardship Program (ASP) in an Intensive Care Unit (ICU), and to assess its effect on the use of antibiotics, quality indicators and clinical outcomes.

Methods: Retrospective description of the interventions proposed by the ASP. We compared antimicrobial use, quality and safety indicators in an ASP versus a non-ASP period. The study was performed in a polyvalent ICU of a medium-size University Hospital (600 beds). We studied patients admitted to the ICU for any cause during the ASP period, provided that a microbiological sample aiming to diagnose a potential infection has been drawn, or antibiotics have been started. We elaborated and registered of non-mandatory recommendations to improve antimicrobial prescription (audit and feedback structure) and its registry during the ASP period (15 months, October 2018-December 2019). We compared indicators in a period with ASP (April-June 2019) and without ASP (April-June 2018).

Results: We issued 241 recommendations on 117 patients, 67% of them classified as de-escalation type. The rate of adherence to the recommendations was high (96.3%). In the ASP period, the mean number of antibiotics per patient (3.3±4.1 vs 2.4±1.7, p=0.04) and the days of treatment (155 DOT/100 PD vs 94 DOT/100 PD, p <0.01) were reduced. The implementation of the ASP did not compromise patient safety or produce changes in clinical outcomes.

Conclusions: The implementation of an ASP is widely accepted in the ICU, reducing the consumption of antimicrobials, without compromising patient safety.