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.
Division of Infectious Diseases, Department of Medicine, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. taggartl@smh.ca.|Department of Medicine, University of Toronto, Toronto, Canada. taggartl@smh.ca.
Linda R
LR
Taggart
Department of Pharmacy, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. leungeli@smh.ca.
Elizabeth
E
Leung
Division of Infectious Diseases, Department of Medicine, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. mullerm@smh.ca.|Department of Medicine, University of Toronto, Toronto, Canada. mullerm@smh.ca.
Matthew P
MP
Muller
Division of Microbiology, Department of Laboratory Medicine, St. Michael's Hospital, 30 Bond Street, Toronto, ON, M5B 1W8, Canada. matukasl@smh.ca.|Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada. matukasl@smh.ca.
Larissa M
LM
Matukas
Department of Medicine, University of Toronto, Toronto, Canada. nick.daneman@sunnybrook.ca.|Division of Infectious Diseases, Department of Medicine, Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, ON, M4N 3M5, Canada. nick.daneman@sunnybrook.ca.
Nick
N
Daneman
D000890:Anti-Infective Agents / Q000191:economics / Q000627:therapeutic use*; D002170:Canada; D003015:Clostridium Infections / Q000188:drug therapy; D016638:Critical Illness / Q000401:mortality; D004926:Escherichia coli / Q000187:drug effects / Q000472:pathogenicity; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D065186:Interrupted Time Series Analysis; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000472:pathogenicity; D016896:Treatment Outcome
D000890:Anti-Infective Agents