The impact of COPD on ICU mortality in patients with ventilator-associated pneumonia

Abstract

Objective: To determine the impact of COPD on intensive care unit (ICU) mortality in patients with VAP.

Methods: This prospective observational study was performed in a mixed ICU during a 3-year period. Eligible patients received mechanical ventilation for >48 h and met criteria for microbiologically confirmed VAP. Risk factors for ICU mortality were determined using univariate and multivariable analyses.

Results: Two hundred and fifteen patients with microbiologically confirmed VAP were included. Most VAP episodes were late-onset (88%), and Pseudomonas aeruginosa was the most frequently isolated bacterium (39% of VAP episodes). ICU mortality was significantly lower in non-COPD patients (n = 150) compared to COPD patients (n = 65) (43.3% vs 60%, p = 0.027, OR [95% CI] = 1.96 [1.8-3.54]). Duration (days) of mechanical ventilation and ICU stay median (IQR) in non-COPD patients were 25 (15-42) and 30 (18-48), whereas in COPD patients were 31 (19-45) and 36 (20-48) (p > 0.05). The differences in duration (days) of mechanical ventilation and ICU stay were significant between non-COPD patients and severe COPD (GOLD stage IV) patients (p = 0.001 and p = 0.02, respectively). Multivariable analysis identified COPD [OR (95% CI) 2.58 (1.337-5)], SAPS II [1.024 (1.006-1.024)] and presence of shock at VAP diagnosis [3.72 (1.88-7.39)] as independent risk factors for ICU mortality.

Conclusion: COPD, SAPS II, and shock at VAP diagnosis are independently associated with ICU mortality in patients who present VAP.