[Long-term follow-up of pulmonary emphysema]

Definition of lung emphysema is based on morphologic criteria (irreversible destruction of alveolar space). In advanced stages of the disease, emphysema may be suspected clinically, by lung auscultation, lung function tests, and radiology. In early stages, there are characteristic functional findings, such as an irreversible decrease in forced expiratory volumes or flows. These simple tests are easily available. In this article, the natural course of lung emphysema is described, based on long term changes in lung function. The typical discrepancy between normal airway resistance and a decrease in FEV1 allows suspicion of early emphysema. In the further development of emphysema, an increase of airway resistance together with hypercapnia indicates severe functional disturbances and cor pulmonale.