Antimicrobial Stewardship Programs: A Review of Recent Evaluation Methods and Metrics

Antimicrobial stewardship program in a Greek hospital: implementing a mandatory prescription form and prospective audits

Aim: Antimicrobial stewardship programs (ASPs) are urgently needed for Greek hospitals in order to improve antibiotic usage. Patients & methods: An ASP was implemented to a Greek hospital since February 2014. A mandatory order form was introduced for five antimicrobials; colistin, tigecycline, daptomycin, doripenem and linezolid. Prospective audits allowed for feedback to the prescribers without direct prescribing restriction. Results: Antimicrobials’ consumption at the baseline year and the 3 years of ASP implementation was 93.7, 99.1, 156.1 and 105.9 defined daily doses/1000 patient days, respectively (p > 0.05). No statistically significant difference in isolation rates of multidrug-resistant pathogens was detected. Conclusion: Efforts are required to demonstrate the long-term impact of our program on antibiotic prescription attitudes as well as antimicrobial resistance rates.

Non-Restrictive Antimicrobial Stewardship Program in a General and Emergency Surgery Unit

BACKGROUND

The goal of an antimicrobial stewardship program (ASP) is to prevent the emergence of antimicrobial drug resistance and reduce adverse drug events, optimizing the selection, dosing, and duration of therapy in individual patients.

METHODS

This retrospective study evaluated changes in antimicrobial agent use associated with implementation of an ASP in a general and emergency unit. The pre-intervention and post-intervention periods were defined as July 1, 2013, to December 31, 2013 (pre-intervention) and January 1, 2014, to June 30, 2014 (post-intervention).

RESULTS

The mean total monthly antimicrobial use decreased by 18.8%, from 1,074.9 defined daily doses (DDD) per 1,000 patient-days to 873.0 DDD per 1,000 patient-days after the intervention. There was a significant reduction in the use of piperacillin-tazobactam, by 33.7% (p < 0.05), in imipenem/cilastatin, by 63.9% (p < 0.05), in meropenem by 68.0% (p < 0.05), and in levofloxacin by 45.0% (p < 0.05) without any negative effect on patient susceptibility to infections. Indeed, patient outcomes, including deaths, length of stay in the hospital, and re-admission within 30 days were not affected.

CONCLUSIONS

The implementation of an education-based ASP achieved a significant improvement in all antimicrobial agent prescriptions in the surgical unit and a reduction in antimicrobial drug consumption, even when no restrictive measures were implemented.

Antimicrobial Stewardship Program Members' Perspectives on Program Goals and National Metrics

PURPOSE

This study compares antimicrobial stewardship program (ASP)-stated goals and outcomes collected as well as opinions regarding national metric establishment.

METHODS

Twenty-one ASP members underwent telephone interviews answering open-ended questions about ASP goals, outcomes collected, and opinions about national metrics. Content analysis was used to code responses into predefined ASP-metric categories.

FINDINGS

The most common ASP goal was antimicrobial appropriateness (76%), outcomes tracked were use and microbial outcomes (both 71%), and desired national metric was use (67%).

IMPLICATIONS

Stated-goals, outcomes tracked, and opinions regarding national metric establishment did not fully align. With ASP-related regulations looming, it is important that alignment is increased.

Assessment of appropriate antimicrobial prescribing: do experts agree?

OBJECTIVES

Little is known about the validity and reliability of expert assessments of the quality of antimicrobial prescribing, despite their importance in antimicrobial stewardship. We investigated how infectious disease doctors' assessments compared with a reference standard (modal expert opinion) and with the assessments of their colleagues.

METHODS

Twenty-four doctors specialized in infectious diseases or clinical microbiology (16 specialists and 8 residents) from five hospitals were asked to assess the appropriateness of antimicrobial agents prescribed for a broad spectrum of indications in 56 paper cases. They were instructed how to handle guideline applicability and deviations. We created a reference standard of antimicrobial appropriateness using the modal assessment of 16 specialists. We calculated criterion validity and interrater and intrarater overall and specific agreement with an index expert (senior infectious disease physician) and analysed the influence of doctor characteristics on validity.

RESULTS

Specialists agreed with the reference standard in 80% of cases (range 75%-86%), with a sensitivity and specificity of 75% and 84%, respectively. This did not differ by clinical specialty, hospital or years of experience, and residents had similar results. Specialists agreed with the index expert in 76% of cases and the index expert agreed with his previous assessments in 71% of cases.

CONCLUSIONS

Doctors specialized in infectious diseases and clinical microbiology assess the appropriateness of antimicrobials prescribed for a broad spectrum of indications with acceptable agreement and validity, regardless of their experience or hospital of employment. However, there is room for improvement, which merits attention in multidisciplinary discussions and education.

Differential outcome of an antimicrobial stewardship audit and feedback program in two intensive care units: a controlled interrupted time series study

BACKGROUND

Antimicrobial decision making in intensive care units (ICUs) is challenging. Unnecessary antimicrobials contribute to the development of resistant pathogens, Clostridium difficile infection and drug related adverse events. However, inadequate antimicrobial therapy is associated with mortality in critically ill patients. Antimicrobial stewardship programs are increasingly being implemented to improve antimicrobial prescribing, but the optimal approach in the ICU setting is unknown. We assessed the impact of an audit and feedback antimicrobial stewardship intervention on antimicrobial use, antimicrobial costs, clinical outcomes and microbiologic outcomes in two ICUs with different patient populations.

METHODS

The audit and feedback intervention was implemented in a trauma and neurosurgery ICU (TNICU) and a medical surgical ICU (MSICU) at a 465-bed teaching hospital in Toronto, Canada. ICU patients were reviewed Monday to Friday by a physician and pharmacist with infectious diseases training. Recommendations related to appropriate antimicrobial use were presented to ICU teams during a dedicated daily meeting. A controlled interrupted time series analysis was used to compare outcomes in the 12 months before and after the intervention. Cardiovascular and coronary care ICUs served as control units.

RESULTS

Mean total monthly antimicrobial use in defined daily doses (DDD) per 1000 patient days was reduced 28% in the TNICU (1433 vs. 1037) but increased 14% in the MSICU (1705 vs. 1936). In the time series analysis, total monthly antimicrobial use in the TNICU decreased by 375 DDD per 1000 patient days (p < 0.0009) immediately following the intervention, followed by a non-significant downward trend in use of -9 DDD per 1000 patient days (p = 0.56). No significant changes in antimicrobial use were identified in the MSICU. Antimicrobial use temporarily increased in one control unit and remained unchanged in the other. There were no changes in mortality, length of stay, readmission rate, incidence of C. difficile infection or resistance patterns of E. coli and P. aeruginosa in either intervention unit.

CONCLUSIONS

Audit and feedback antimicrobial stewardship programs can lead to significant reductions in total antimicrobial use in the ICU setting. However, this effect may be context-dependent and further work is needed to determine the ingredients necessary for success.

Demonstrating the value of antimicrobial stewardship programs to hospital administrators

The movement away from fee-for-service models to those that emphasize quality of care and patient outcomes affords a unique opportunity for antimicrobial stewardship programs to expand their value for hospital administration. Antimicrobial stewardship participants must collaborate with administrators and key stakeholders to position themselves to improve economic, process, and outcomes measures. This will allow the establishment of antimicrobial stewardship programs as essential components of the present and future healthcare quality journey.