Trends in use and impact on outcome of empiric antibiotic therapy and non-invasive ventilation in COPD patients with acute exacerbation

Islem Ouanes, Lamia Ouanes-Besbes, Saoussen Ben Abdallah, Fahmi Dachraoui, Fekri Abroug

Empiric antibiotic therapy is routinely prescribed in patients with acute COPD exacerbations (AECOPD) requiring ventilatory support on the basis of studies including patients conventionally ventilated. Whether this practice remains valid to current management with first-line non-invasive ventilation (NIV) is unclear. In a cohort of ICU patients admitted between 2000 and 2012 for AECOPD, we analyzed the trends in empiric antibiotic therapy and in primary ventilatory support strategy, and their respective impact on patients' outcome. 440 patients admitted for 552 episodes were included; primary NIV use increased from 29 to 96.7 % (p < 0.001), whereas NIV failure rate decreased significantly (p = 0.004). In parallel, ventilator-associated pneumonia (VAP) rate, VAP density and empiric antibiotic therapy use decreased (p = 0.037, p = 0.002, and p < 0.001, respectively). These figures were associated with a trend toward lower ICU mortality rate (p = 0.058). Logistic regression showed that primary NIV use per se was protective against fatal outcome [odds ratios (OR) = 0.08, 95 %CI 0.03-0.22; p < 0.001], whereas NIV failure, VAP occurrence, and cardiovascular comorbidities were associated with increased ICU mortality [OR = 17.6 (95 %CI 5.29-58.93), 11.5 (95 %CI 5.17-25.45), and 3 (95 %CI 1.37-6.63), respectively]. Empiric antibiotic therapy was associated with decreased VAP rate (log rank; p < 0.001), but had no effect on mortality (log rank; p = 0.793). The sustained increase in NIV use allowed a decrease in empiric antibiotic prescriptions in AECOPD requiring ventilatory support. Primary NIV use and its success, but not empiric antibiotic therapy, were associated with a favorable impact on patients' outcome.