Purpose: To evaluate the incidence of surgical site infections (SSI), as related to risk factors, in patients undergoing lung resections (LR).
Methods: We evaluated 988 consecutive patients prospectively who underwent LR between 1996 and 2005 at the Center for Thoracic Surgery of the University of Insubria, Varese, Italy. Patients were divided into four groups: Pneumonectomy (n=104), lobectomy/bi-lobectomy (n=438), wedge resection by thoracotomy (n=155), and wedge resection by video-thoracoscopy (VATS) (n=291). The recorded risk factors for SSI were hemoglobin concentration, serum albumin concentration, lymphocyte count, percentage of predicted forced expiratory volume in 1 sec (FEV1), duration of surgery, blood transfusion, age>70 years, and comorbidity. The postoperative SSIs (superficial and deep incisional SSI, pneumonia, empyema) were recorded in they occurred within 30 days, and the final outcome was recorded.
Results: Postoperative infections were found in 141 patients (14.3%) and included 166 thoracic infections, among them 32 incisional SSIs (3.2%), 103 cases of pneumonia (10.4%); and 24 empyemas (2.4%). The overall incidence of SSI was significantly lower in patients having wedge resections by VATS (5.5%) than in the other three groups (17.9%) (p<0.001). The overall mortality rate was 1.2% (12/988), of which six deaths (0.6%) were caused by complications of infection. The infection rate correlated with duration of surgery>180 min, age>70 years, serum albumin<3.5 g/dL, and the presence of any comorbidity. Moreover, 18% of patients with FEV1>70% had postoperative pneumonia, a significant increase (p<0.01) compared with patients with FEV1>or=70%.
Conclusions: In this prospective study, the SSI rate after LR was 14.3%, and the 30-day operative mortality rate was 1.2%, with most of the deaths caused by pneumonia. After VATS LR procedures, the incidence of SSI was lower at 5.5%. Finally, SSI correlated with the duration of surgery, serum albumin, concurrent comorbidity, age, and FEV1.