A surgical approach to pulmonary emphysema.

SUMMARY Pulmonary emphysema is classified into primary and secondary types. Each of these is further subdivided into generalized and localized groups. In the localized type of pulmonary emphysema there is airway obstruction only to the area involved by disease. The remainder of the lung is normal. In the generalized or diffuse type of bilateral pulmonary emphysema there is generalized bronchiolaralveolar airway obstruction to all lung tissue whether or not there are blebs and/or bullae. Bronchioles are collapsible tubes. They are normally held open by the physiologic principle of circumferential pull upon the bronchioles. The normal elastic lung is held expanded by a rigid chest wall which causes the lung elasticity to be transferred to a circumferential pull upon the bronchioles. As the chest expands on inspiration the bronchioles are enlarged. The relaxation of the chest on expiration causes the bronchioles to become smaller in diameter. Thus, the expiratory airway obstruction is at least partially accounted for in primary pulmonary emphysema. Whatever may be the cause for the beginning of bronchiolar-alveolar airway obstruction in pulmonary emphysema, the partial loss of the physiologic principle of holding open the bronchioles is an important factor in the well developed disease. Surgery directed at reducing lung volume by sacrifice of functionally useless pulmonary tissue can in some measure restore the partially lost physiologic principle of holding open the bronchioles. Tenaceous sputum in small amounts is characteristic of pulmonary emphysema. The character of the secretion can be altered by denervation of the lung. Of 56 patients operated upon for primary pulmonary emphysema, 42 (75 per cent) are improved. When there occurs a loss of improvement gained by operation on one lung of a patient with primary pulmonary emphysema, the loss of function is usually the result of further degeneration of the unoperated lung. In none of the patients reported in this series has there been detectable evidence of further progression of the disease in the operated lung. The longest follow-up has been eight years. Undoubtedly, some patients will in the future show signs of further progression of the disease.