Airway bacterial colonization in patients with non-small cell lung cancer and the alterations during the perioperative period.

Background: To observe the alterations in airway bacterial colonization during the perioperative period in patients with non-small cell lung cancer (NSCLC) and evaluate their clinical implications.

Methods: Patients with resectable primary NSCLC were enrolled from October 2011 to April 2012. Airway secretions were harvested for microbiological study after admission, immediately after surgery, and before endotracheal extubation. Spontaneous sputum was collected when patients presented with signs of postoperative pneumonia (POP). Detailed data on the isolated pathogens were carefully recorded. Risk factors for airway colonization and POP were analyzed.

Results: A total of 78 consecutive patients were enrolled. Fourteen patients (17.9%) had airway colonization at admission, including four cases of fungi and ten cases of Gram-negative bacilli (GNB). Five patients (6.4%) had colonized pathogens at the end of surgery, including three cases of GNB and two cases of Gram-positive cocci. Nine (11.5%) patients had positive culture of airway secretions collected before extubation, including seven cases of GNB and two cases of fungi. Eighteen patients (23.1%) had POP, of whom one suffered from bronchopleural fistula and one died of POP. Pathogens of POP were confirmed in 11 patients, including nine cases of GNB and two cases of fungi. Three patients had the same pathogens as preoperative colonization. The proportion of more antibiotic-resistant strains increased gradually. Advanced age [odds ratio (OR), 2.263; 95% confidence interval (95% CI), 1.030-4.970] and smoking (OR, 2.163; 95% CI, 1.059-4.429) were risk factors for airway colonization. Decreased diffusion capacity of the lung for carbon monoxide (OR, 5.838; 95% CI, 1.318-25.854), prolonged operation time (OR, 6.366; 95% CI, 1.349-30.033), and preoperative airway colonization (OR, 9.448; 95% CI, 2.206-40.465) were risk factors of POP.

Conclusions: Airway colonized pathogens altered and more antibiotic-resistant GNB emerged during the perioperative period. These pathogens played an important role in the presence of POP.