Risk factors of postoperative respiratory infections in lung cancer surgery

BACKGROUND: Postoperative infections have been a major issue in lung cancer surgery. We changed our perioperative prophylactic antibiotic policy to a single dose of cefazolin before and after surgery in July 2002. OBJECTIVE: To identify the risk factors of postoperative pneumonia and empyema in lung cancer patients undergoing surgical resection. METHODS: From July 1992 through September 2003, 2105 patients underwent primary lung cancer resection at our division. We reviewed 1855 eligible patients for possible risk factors of pneumonia and empyema. RESULTS: Postoperative respiratory infections developed in 69 (3.7%) patients. There were 58 (3.1%) pneumonia cases and 18 (1.0%) cases of empyema. The mortality rate was 0.8% (15 patients). Nine (0.5%) patients died from postoperative respiratory infections. Multivariate analysis showed age 75 years or older, forced expiratory volume in 1 second as a percentage of forced vital capacity (FEV1%) less than 70%, advanced pathologic stage, and induction therapy to be independent risk factors of pneumonia. For postoperative empyema, advanced age was the significant factor. Twelve of 18 patients (67%) with empyema were complicated with bronchopleural fistula. The infection incidence rate did not change significantly after we modified our prophylactic antibiotic policy to a single dose of cefazolin before and after surgery. CONCLUSIONS: Lung cancer patients with advanced age, low FEV1%, advanced pathologic stage, or induction therapy had a risk for pneumonia after lung cancer surgery. Postoperative empyema was associated with advanced age.