Abstract & Commentary

Audit Feedback Reduced Broad-Spectrum Antibiotic Use and Incidence of C. difficile Infections

By Leslie A. Hoffman, RN, PhD, Department of Acute/Tertiary Care, School of Nursing, University of Pittsburgh, is Associate Editor for Critical Care Alert.

Synopsis: Institution of a formal audit and feedback program resulted in a decrease in use of broad-spectrum antibiotics and a 31% reduction in cases of Clostridium difficile infection.

Source: Elligsen M, et al. Audit and feedback to reduce broad-spectrum antibiotic use among intensive care unit patients: A controlled interrupted time series analysis. Infect Control Hosp Epidemiol 2012;33:354-361.

This study was conducted to evaluate the impact of a formal audit and feedback program targeted at broad-spectrum antibiotic use in critically ill patients. The study was conducted in three intensive care units (ICUs) in a single institution in Toronto: a 20-bed general ICU, a 14-bed cardiovascular ICU, and a 14-bed burn center. Records of all patients who received 3 days of therapy with broad-spectrum antibiotics were reviewed by a designated pharmacist. If an opportunity for optimization was identified, the case was reviewed with an infectious disease staff physician. If the suggestion was approved, a computer-generated progress note was placed in the patient's chart and the pharmacist provided verbal feedback to available members of the critical care team. The process was structured to provide assessment, review, and feedback within 24 hours. A similar review was performed on the 10th day of therapy to advise clinicians regarding excessive duration of treatment. All decisions to change therapy rested with the critical care team. The control group consisted of patients admitted to non-ICU wards during the same time period.

During the 12-month data collection period, 2339 patients were admitted to the three ICUs for a total of 15,431 patient days. Pharmacists evaluated 717 antibiotic prescriptions and made recommendations for change in 247 cases (34%); most (82%) recommendations were accepted by the critical care team. The most common recommendations were to discontinue the antibiotic (56%), change the antibiotic (26%), or change dose, frequency, or route (8%). Mean monthly broad-spectrum antibiotic use decreased from 644 days per 1000 patient days per month (preintervention) to 503 days per 1000 patient days per month (postintervention; P < 0.0001) with no change in non-ICU (control) units. The number of monthly Clostridium difficile infections decreased by 31% (n = 16 preintervention; n = 11 postintervention) compared to an increase (33%) in non-ICU units (n = 87 preintervention; n = 116 postintervention; P = 0.04). ICU length of stay and mortality were unchanged.


In this study, as in studies testing use of a weaning protocol to improve patient outcomes, positive changes resulted from introduction of a structured routine daily assessment. Pharmacist review, followed by a computer-generated progress note and verbal feedback, led to a substantial (22%) reduction in broad-spectrum antimicrobial use in the ICUs that was sustained for the 12-month duration of the study. There was no change in use of broad-spectrum antibiotics in control (non-ICU) units, supporting that the reduction was a result of the intervention. Most (82%) suggestions were accepted, an outcome that authors attributed to timing of the pharmacist recommendations which occurred on the third and tenth day of broad-spectrum antibiotic therapy. This timing allowed the pharmacist to incorporate microbiologic data and information about response to current therapy into the recommendation.

Prior studies have reported similar findings as a result of programs that incorporated a similar assessment. However, none reported a decrease in C. difficile infection as a result of a structured monitoring program. The authors therefore questioned whether this approach — reduction in patient susceptibility through antibiotic avoidance — may be more successful than traditional infection control measures that focus on hand hygiene, contact precautions, and isolation, all of which have known compliance issues. Systematic assessment on a specific day of antibiotic therapy, with case-by-case feedback to the critical care team, appears to be a safe, effective, and easily-introduced means to enhance patient outcomes. The recommendations had a high acceptance rate and were associated with highly positive consequences.