AN ANTIMICROBIAL STEWARDSHIP PROGRAM IMPROVES THE QUALITY OF ANTIMICROBIAL PRESCRIBING IN AN ICU
AUTHORS: Katsios, Christina M.; Burry, Lisa; Khory, Tanaz; Howie, Sandra; Wax, Randy; Bell, Chaim; Lapinsky, Stephen; Mehta, Sangeeta; Stewart, Thomas; Morris, Andrew
BACKGROUND: Growing antimicrobial resistance, decreased development of novel antimicrobials, and antimicrobial costs necessitate their judicious use. Antimicrobial stewardship programs (ASP) are one potential means of improving antimicrobial use in an intensive care unit (ICU). Positive microbial cultures in critically ill patients often prompt the initiation of therapy, regardless of sampling site or contamination potential. Discontinuation of empiric therapy based on clinical criteria or negative cultures has proven to reduce hospital stay and impact mortality. Our objective was to determine if an ASP altered the decision to treat sterile vs. non-sterile culture sites and to appropriately tailor regimens.
METHODS: We retrospectively analyzed ICU patients pre and post-ASP (April-May 2008 and 2009, respectively). Parameters collected included demographics, antimicrobial regimens, culture results, chart documentation of antimicrobials, mortality, costs and defined daily doses (DDD) per 100 patient days. Culture results were separated into sterile sites and non-sterile sites specified a priori and analyzed using the Chi Square test. ICU chart documentation were analyzed for inclusivity of antimicrobial start/stop dates, de-escalation, and details on clinical decision making.
RESULTS: There was no significant difference between age distribution, sex, APACHE II score, or types of ICU admissions between pre (n=139) and post (n=139). 82.7% of pre-ASP vs. 77.7% of post-ASP patients received antibiotics during ICU stay. There were 215 positive cultures pre-ASP vs. 179 post-ASP. There was no difference in number of positive cultures from sterile sites between the pre-ASP (42.3%) vs. post-ASP period (40.2%). Post-ASP, there was an observed trend towards treating more sterile cultures (83.3% vs. 71.4% treated) and treating less nonsterile cultures (45.8% vs. 71.0% treated). Pre-ASP 65 sterile and 88 non-sterile cultures were treated (χ2 = 0.005, p = 0.941) vs. 60 sterile and 58 non-sterile cultures post-ASP (χ2 = 25.47, p<0.05). The decision to treat positive nonsterile cultures dropped significantly post-ASP (χ2 = 4.026, p = 0.045). ICU chart documentation had increased antibiotic documentation post-ASP (70.5% vs. 26.4%). Post-ASP there was a 19% (72% vs 53%) increase in formally documented stop dates, and a 8% (23% vs 15%) increase in appropriate de-escalization or tailoring. There was a 3.0% decrease in overall ICU actual mortality post-ASP. There was a 40% reduction in total antibiotic costs ($37605.02 vs. $22707.35) as well as a 35% reduction in antibiotic cost per ICU bed day ($44.03 vs. $28.45) post- ASP. Furthermore, there was a 9.2% reduction in mean antibacterial DDD/100 patient days post-ASP (142.26 vs 129.2).
CONCLUSION: The ASP and ICU team worked collaboratively to use antimicrobials appropriately. As a result, the ASP minimized unnecessary use, tailored spectrum of activity, decreased antimicrobial costs and overall usage, and promoted better patient care practices. ASP implementation was associated with a statistically significant reduction in the number of non-sterile cultures being treated, an increase in the number of sterile sites being treated, and more transparent chart documentation. Appropriate and judicious antimicrobial use guided by an ASP is associated with significant benefit in critically ill ICU patients.