Impact of nonexacerbated COPD on mortality in critically Ill patients

Background: The real contribution of nonexacerbated COPD to mortality has not been studied. The aim of our study was to evaluate the impact of nonexacerbated COPD on mortality in patients requiring mechanical ventilation (MV). Methods: This prospective, observational study included critically ill, ventilated patients without evidence of respiratory infection. Patients with COPD comprised the study group. Clinical and demographics variables were recorded. The main end point was ICU mortality. Results: Of the 235 patients included, 60 (25.5%) intubated patients had COPD. The remaining 175 (74.5%) comprised the control group. Those with COPD were more often medical patients who were older and had a higher number of comorbidities and a higher APACHE (Acute Physiology and Chronic Health Evaluation) II score than intubated patients without COPD (P < .05). The overall ICU mortality was 26.3% (62/235) and significantly higher in patients with nonexacerbated COPD (36.7% vs 22.9%, P < .05), with an attributable mortality to COPD of 13.8%. Incidence of ventilator-associated pneumonia was not significantly different between patients with nonexacerbated COPD (11.9/1,000 MV days) and without COPD (16.0/1,000 MV days; P = .40). In the multivariate analysis, only COPD (hazard ratio [HR], 2.1; 95% CI, 1.10-3.94), shock at ICU admission (HR, 2.0; 95% CI, 1.01-4.01), and medical condition (HR, 1.7; 95% CI, 1.01-3.18) were independently associated with mortality. Conclusions: Intubated patients with nonexacerbated COPD were not exposed to a higher risk of ventilator-associated pneumonia but had a higher rate of mortality. © 2011 American College of Chest Physicians.