Pulmonary complications after lung resection in the absence of chronic obstructive pulmonary disease: The predictive role of diffusing capacity

Objective: Diffusing capacity is not routinely used in assessing risk of lung resection, perhaps owing to uncertainty as to whether patients with normal spirometric results require additional evaluation. We determined whether diffusing capacity is predictive of pulmonary complications after lung resection in patients with normal spirometric results. Methods: We reviewed outcomes of major lung resection in The Society of Thoracic Surgeons General Thoracic Surgery Database from 2002 to 2008 to determine the relationship of diffusing capacity (expressed as percent of predicted) to postoperative pulmonary complications stratified by chronic obstructive pulmonary disease status. Results: Percent of predicted diffusing capacity was measured in 7891 (57%) patients. There were 3905 women and 3986 men with a mean age of 66.3 +/- 10.6 years who underwent lobectomy (6904; 87.5%), bilobectomy (463; 5.9%), and pneumonectomy (524; 6.6%). Chronic obstructive pulmonary disease was identified in 2711 (34.4%) patients. Pulmonary complications occurred in 13%, and the operative mortality was 1.9%. Percent of predicted diffusing capacity was strongly associated with the development of pulmonary complications (odds ratio, 1.12 per 10-point decrease; P < .0001). Decreasing percent of predicted diffusing capacity was incrementally related to an increased incidence of pulmonary complications regardless of chronic obstructive pulmonary disease status. There was no apparent interaction between percent of predicted diffusing capacity and chronic obstructive pulmonary disease status in the predictive model. Conclusions: Percent of predicted diffusing capacity predicts pulmonary complications after lung resection in patients without chronic obstructive pulmonary disease. We recommend measurement of diffusing capacity in lung resection candidates, regardless of chronic obstructive pulmonary disease, as an important element in the accurate assessment of operative risk. (J Thorac Cardiovasc Surg 2009;138:1297-302)