What is antimicrobial stewardship and its practical application?

Antimicrobial Stewardship: Definition and Practical Application

Antimicrobial stewardship is a coordinated set of interventions designed to improve and measure the appropriate use of antimicrobial agents by promoting the selection of optimal drug regimens including dosing, duration of therapy, and route of administration to optimize clinical outcomes while minimizing unintended consequences of antimicrobial use. 1

Core Principles and Definition

• Antimicrobial stewardship programs (ASPs) aim to optimize clinical outcomes while minimizing adverse events including Clostridium difficile infections, reducing antimicrobial resistance, and optimizing resource utilization across the continuum of care 1
• The primary goal of antimicrobial stewardship is to improve patient outcomes while minimizing the unintended consequences of antimicrobial use, including adverse events, selection of pathogenic organisms, and emergence of resistance 1
• Appropriate antimicrobial prescribing requires following the "5Ds of stewardship": right diagnosis, drug, dose, duration, and de-escalation 1
• Antimicrobial resistance has emerged as a critical threat to public health, making antimicrobial stewardship a fiduciary responsibility for all healthcare institutions 2

Core Components of Successful ASPs

• Leadership by infectious disease physicians with additional stewardship training, partnered with clinical pharmacists with infectious disease expertise 1, 3
• Implementation of preauthorization and/or prospective audit and feedback interventions as primary strategies (strong recommendation, moderate-quality evidence) 1
• Collaboration between clinicians, pharmacists, microbiologists, infectious disease specialists, and primary care providers 3
• Development of facility-specific clinical practice guidelines based on local resistance patterns 3
• Dedicated representation from all clinical areas on antimicrobial stewardship committees to ensure comprehensive implementation 3
• Active educational programs including seminars and roundtable discussions to promote clinician engagement 3, 4

Key Intervention Strategies

• Prospective audit and feedback on antimicrobial prescriptions with real-time intervention to optimize antibiotic use 3, 4
• Formulary restriction and preauthorization to control use of specific antimicrobials 1, 5
• Implementation of biomarker testing (e.g., procalcitonin) and rapid pathogen identification to improve antibiotic prescribing decisions 3, 4, 6
• Selective use of blood cultures in patients with suspected infections, particularly when signs of sepsis are absent 4
• Watchful waiting or delayed antibiotic prescribing for select patients with less severe infections 3, 4
• Structured culture follow-up programs for patients discharged with pending cultures 3, 4
• Shortening duration of therapy according to current guidelines to reduce selective pressure for resistant bacteria 3, 4
• Dose optimization based on patient characteristics, pathogen, infection site, and pharmacokinetic/pharmacodynamic properties 3, 4
• De-escalation of therapy and intravenous-to-oral switch when appropriate 7

Setting-Specific Considerations

Emergency Department Implementation

• Emergency departments require special consideration due to rapid patient turnover, need for quick decision-making, and high provider variability 3, 4
• ED clinician representation on hospital antimicrobial stewardship committees is essential for successful implementation 4
• Rapid diagnostic testing to distinguish between viral and bacterial pathogens can reduce unnecessary antibiotic use in the ED setting 4
• Blood cultures should be obtained selectively in patients with community-acquired pneumonia, urinary tract infections, or skin/soft tissue infections, particularly when signs of sepsis are absent 4

Intensive Care Unit Implementation

• Multi-intervention ASP programs have consistently demonstrated reduction in antimicrobial utilization in ICU settings 5
• Procalcitonin protocols for guiding antimicrobial use are particularly effective in ICU environments 5
• Protocols for antimicrobial de-escalation are important in ICU settings where broad-spectrum empiric therapy is often initiated 5

Monitoring and Measurement

• Tracking antimicrobial utilization patterns and resistance trends is crucial for evaluating ASP effectiveness 3
• Monitoring appropriateness of antibiotic therapy choice, rehospitalization rates, and time to culture review provides important metrics 3, 4
• Process and outcome measures should track antimicrobial utilization and resistance patterns 4

Implementation Challenges and Pitfalls

• Provider concerns about medical liability and failure to diagnose/treat can be barriers to implementation 3
• Patient satisfaction pressures and expectations for antibiotics can challenge ASP goals 3
• Resource constraints and operational efficiency concerns can impact program implementation 3
• Tension exists between appropriate broad-spectrum antibiotic use for life-threatening infections and stewardship goals 3, 4
• Implementing education alone without complementary strategies is insufficient for sustained practice change 3
• Failing to adapt guidelines to local resistance patterns and patient populations reduces program effectiveness 3
• Neglecting to include frontline clinicians in program development leads to program failure 3
• Overlooking the importance of diagnostic stewardship alongside antimicrobial stewardship reduces program effectiveness 3, 8

Connection to Infection Prevention and Control

• Prevention and control of healthcare-associated infections (HAIs) should be considered the first principle of every antimicrobial stewardship program 8
• HAIs frequently require broader-spectrum antibiotic regimens due to higher risk of multidrug-resistant organisms, which promotes further resistance 8
• Effective infection prevention and control measures must be integrated with antimicrobial stewardship efforts 8