Out of sight, out of mind: Impact of an antimicrobial stewardship initiative to reduce fluoroquinolone utilization

Abstract

AbstractIntroductionIn June 2017, the antimicrobial stewardship team at Wesley Healthcare implemented a combination of strategies aimed at reducing fluoroquinolone usage. The components included suppression of fluoroquinolone susceptibility in Enterobacterales isolates, removal of fluoroquinolones as first‐line options in order sets, and introduction of a respiratory‐specific antibiogram.ObjectivesThe objective was to evaluate the impact of combined stewardship strategies on fluoroquinolone utilization.MethodsThis was a quality improvement study evaluating fluoroquinolone use within a health‐care system. The primary outcome was ciprofloxacin and levofloxacin usage in days of therapy (DOT) per 1000 inpatient days collected at monthly intervals for 24 months before and after the intervention. Overall antibacterial usage in DOT served as a control variable. The secondary outcomes were Escherichia coli and Pseudomonas aeruginosa susceptibility to ciprofloxacin measured at the same time points. An interrupted time series analysis using segmented regression was performed for all variables.ResultsThe mean monthly levofloxacin usage was reduced from 14.1 (95% confidence interval [CI], 12.7‐15.4) to 8.4 (95% CI, 7.6‐9.3) DOT. The mean monthly ciprofloxacin usage was reduced from 26.9 (95% CI, 24.6‐29.4) to 15.8 (95% CI, 14.0‐17.5) DOT. The trend in levofloxacin usage was reduced (P = .035), while a pre‐existing downward trend in ciprofloxacin usage was unchanged (P = .430). Overall antibacterial usage increased (P = .001). There were no differences in Escherichia coli or Pseudomonas aeruginosa susceptibilities observed.ConclusionThe use of combined antimicrobial stewardship strategies may be a viable intervention method to reduce fluoroquinolone usage. The combined strategy was effective in reducing levofloxacin usage, as demonstrated by the reduction of use and the downward usage trend.