Evaluation of Antimicrobial Stewardship Programs and Their Impact on Multidrug-Resistant Organisms in ICU Settings

Abstract

The emergence and rapid dissemination of multidrug-resistant organisms (MDROs) have become a major challenge in intensive care units (ICUs), contributing to increased morbidity, mortality, healthcare costs, and prolonged hospital stays. Excessive and inappropriate use of antimicrobial agents remains one of the primary drivers of antimicrobial resistance, particularly among critically ill patients who frequently require broad-spectrum antibiotic therapy. Antimicrobial Stewardship Programs (ASPs) have been developed to optimize antimicrobial utilization, improve patient outcomes, minimize adverse drug events, and reduce the development and transmission of resistant pathogens. This review evaluates the effectiveness of ASPs in ICU settings and examines their impact on controlling multidrug-resistant organisms. Evidence from recent clinical studies demonstrates that interventions such as prospective audit and feedback, formulary restriction, antibiotic de-escalation, rapid diagnostic testing, guideline-based prescribing, and multidisciplinary stewardship teams significantly improve antibiotic appropriateness and reduce antimicrobial consumption. Furthermore, successful ASP implementation has been associated with reductions in the incidence of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), carbapenem-resistant Enterobacterales (CRE), and multidrug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii. Despite these benefits, challenges including limited resources, diagnostic uncertainty, clinician resistance, and variability in stewardship practices continue to hinder optimal implementation. The integration of artificial intelligence, rapid molecular diagnostics, and real-time surveillance systems offers promising opportunities for enhancing stewardship effectiveness in critical care environments. Overall, antimicrobial stewardship represents a crucial strategy for combating antimicrobial resistance and improving patient safety in ICU settings. Continuous monitoring, multidisciplinary collaboration, and evidence-based interventions are essential for sustaining long-term reductions in MDRO prevalence and preserving the effectiveness of existing antimicrobial therapies.