Bronchial colonization and postoperative respiratory infections in patients undergoing lung cancer surgery

Study objectives: To evaluate the risk factors associated with postoperative respiratory infection in patients undergoing lung cancer surgery, with special emphasis on the perioperative pattern of airway colonization. Design: Prospective cohort study. Setting: Department of Pneumology and Thoracic Surgery of a tertiary hospital. Patients: Seventy-eight consecutive patients undergoing lung cancer surgery, were evaluated. Patients were followed up until hospital discharge or death. Interventions: Fiberoptic bronchoscopies with bilateral protected specimen brush or bronchial aspirates were performed during anesthesia prior to the initiation of the surgical procedure. Results: Sixty-five patients (83%) had perioperative bronchial colonization by either potentially pathogenic microorganisms (PPMs) [28 patients, 36%] or nonpotentially, pathogenic microorganisms (56 patients, 72%). The 24 patients (31%) with a postoperative respiratory infection (pneumonia, purulent tracheobronchitis, or pleural empyema) had significantly higher perioperative bronchial colonization by, PPMs (15 patients [63%] vs 13 patients [24%], p = 0.003) and a higher bacterial index (mean SD, 3.6 +/- 3.3 vs 0.9 +/- 1.4; p = 0.003), compared to patients without infection. The agreement between pathogens found in perioperative evaluation and during postoperative infection was total in 5 patients (21%), partial in 5 patients (21%), and no concordance in 14 patients (58%). In the multivariate analysis, the presence of perioperative airway colonization by, a PPM (odds ratio [OR], 6.9; p = 0.001) and a higher postoperative pain score (OR, 4.1; p = 0.014) were independent predictors of postoperative respiratory, infection. Conclusion: Adequate control of postoperative pain, as well as the conditions that potentially cause airway colonization by PPMs, could be beneficial in preventing postoperative respirators infections after lung cancer, surgery.