ObjectiveTo analyze the clinical characteristics and pathogenesis in patients with chronic obstructive pulmonary disease (COPD) with ventilator-associated pneumonia (VAP). MethodsNinety-two patients with VAP who underwent mechanical ventilation via tracheal incubation due to COPD and respiratory failure were recruited in the study.The clinical characteristics,bacterial culture and antibiotics sensitivity of specimen from tracheal secretion and bronchoalveolar lavage fluid were retrospectively analyzed. ResultsThe main pathogenic bacteria in the patients with COPD with VAP were as following,ie. Ainetobacter baumanii(24.1%),Pseudomonas aeruginosa (17.6%),Klebsiella spp (15.9%),Methicillin-resistant Staphylococcus aureus(14.7%),and Escherichia coli(10.6%) in which Gram negative bacteria were predominant. When compared with the patients who received antibiotics before mechanical ventilation,the mortality in the patients who did not receive antibiotics before mechanical ventilation was significantly lower (17.9% vs. 40.6%,P<0.01). The patients who received de-escalation antibiotics therapy had lower mortality than those who received escalation antibiotics therapy(19.3% vs. 57.1%,P<0.01). There was no significant difference in mortality between the patients who suffered from VAP less or more than 4 days after mechanical ventilation (54.8% vs. 45.2%,P>0.05). ConclusionsHigh drug resistant rate is observed in patients with COPD and VAP especially in those patients who using antibiotic before mechanical ventilation. De-escalation antibiotics therapy can lower the mortality. The mortality rate is not significant different between early-onset and late-onset VAP in patients with COPD.