Volume reduction surgery in the native lung after single lung transplantation for emphysema

The natural history of emphysema suggests that progression of disease in the native lung may contribute to late deterioration in respiratory function after single lung transplantation. In this report, we describe our experience with unilateral volume reduction surgery in three single lung transplant recipients with emphysema. Each patient had had a late decline in lung function with a recurrence of symptoms. Chest radiographs demonstrated hyperinflation of the native lungs with encroachment on the grafts. Serial pulmonary function testing documented progressive reduction in expiratory flows with increases in residual volumes. Exercise testing confirmed severe intolerance to maximal exercise. Unilateral volume reduction surgery was undertaken at 36, 39, and 55 months after transplantation without incident. Radiographs obtained after the procedures demonstrated restoration of normal diaphragmatic contour, decreased aeration of the native lungs, and improved inflation of the allografts. Exercise testing at 3 months documented a mean improvement in maximal oxygen consumption of 35%. Expiratory flows improved by a mean of 60%. Quantitative ventilation and perfusion scans, however, were essentially unchanged. This experience suggests that unilateral volume reduction surgery may be considered as an alternative strategy in single lung transplant recipients with emphysema who exhibit clinically significant functional deterioration. Differentiation of the adverse effects of hyperinflation of the native lung from other potential causes of late deterioration might not be necessary but may be predictive of the degree of functional improvement after volume reduction. The relief of thoracic overdistention seems to play a primary role in the improvement pulmonary function.