Effect of a procalcitonin protocol with active antimicrobial stewardship pharmacist feedback on antibiotic use in acute exacerbations of chronic obstructive pulmonary disease: a pragmatic interrupted time series study

Abstract Objective: Evaluate the influence of a procalcitonin (PCT) protocol and the incremental impact of a focused antimicrobial stewardship pharmacist intervention on antimicrobial exposure and hospital length of stay in acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Design: Prospective, observational, interrupted time series. Setting: Safety-net teaching hospital in Oakland, California. Methods: We compared the care and outcomes of inpatients with non-severe AECOPD during three periods: Baseline Phase (before PCT testing), Intervention Phase I (after introduction of PCT testing and education) and Intervention Phase II (PCT testing and education plus an antimicrobial stewardship intervention to promote adherence). The primary study outcome was antibiotic exposure measured as mean antibiotic days per AECOPD episode. Results: 341 total admissions were included, 134 in the Baseline Phase, 121 in Intervention Phase I and 86 in Intervention Phase II. Patient comorbidities were well balanced. Mean (SD) total antibiotic days decreased across the study from 4.7(3.8) to 3.5 (3.2) to 2.1(2.7) days in the Baseline Phase, Intervention Phase I and Intervention Phase II, respectively ( P < .001). Median (IQR) hospital lengths of stay decreased from 3.7(2.6–5.2) to 2.8 (1.5–5.2) to 1.5(0.3–4.1) days ( P = .003). Inclusion in Intervention Phase II was the strongest predictor of total antibiotic days (IRR = 0.45,95% CI [0.64–0.83]) and hospital length of stay (IRR = 0.68, 95% CI [0.53–0.88]). All cause 30-day readmission rates were similar across the study (16%, 21%, and 21%; p -trend 0.16). Conclusions: Reductions in antimicrobial exposure and hospital length of stay achieved with PCT testing alone improved further with addition of a focused antibiotic stewardship pharmacist intervention.