Background: Postoperative pulmonary complications (PPC) result in increased morbidity and mortality after lung resection. Pulmonary risk factors such as predicted lung function have been studied extensively. The contribution of non-pulmonary factors is less clear. Our aim was to define possible risk factors for PPC at a large regional thoracic surgical unit.

Methods: A prospective observational study was performed on all patients following lung resection via thoracotomy in a regional thoracic centre over 9 months. The following measures were recorded: chest radiographs showing consolidation or atelectasis, elevated white cell count .11.2 or administration of antibiotics postoperatively, temperature above 38uC, positive sputum microbiology, production of purulentsputum, oxygen saturations , 90% on room air, diagnosis of pneumonia/chest infection by physician or readmission or prolonged stay to the ITU/HDU with respiratory problems. Scoring positive for four or more measures was considered indicative of postoperative respiratory infection/clinically significant atelectasis.

Results: 155 subjects were observed. Mean (SD) age was 61 years (15), 91 men (60%). Surgical procedures included 19 pneumonectomies, 77 lobectomies, nine segmentectomies, 43 wedge resections, four exploratory thoracotomies and three sleeve resections: 20 subjects met four or more criteria (13%) and all had clinical evidence of PPC as assessed by the physician. These subjects had a mean (SD) age of 65 years (12) of which 15 (75%) were men. Higher body mass index (BMI; 26 ¡ 4 vs 29 ¡ 4), preoperative activity level less than 400 m (20% vs 47%), ASA score above 3 (51% vs 84%) and percentage predicted FEV1 (84% ¡ 20% vs 71% ¡ 18%) were all significantly (p,0.05) associated with PPC on univariate analysis. The PPC patient group also demonstrated a significantly longer hospital length of stay (LOS; 6 ¡ 3 vs 14 ¡ 6 days) and high dependency unit LOS (1.0 ¡ 0.0 vs 1.4 ¡ 0.5 days).

Conclusion: High BMI, ASA score, lower preoperative activity level and predicted FEV1 are all significant risk factors for the development of PPC following major lung surgery. Preoperative modification may alter these risks and targeted therapy in these high-risk groups may reduce the morbidity and mortality of PPC.