Relationship between pulmonary function and radiological findings was investigated in 53cases of pulmonary tuberculosis receiving pneumonectomy. The cases were classified radiologically into the following 4 types according to the grade of overdistension of lung; none (0), slight (I), moderate (II) and marked (III).
The proportion of patients with typ e III was higher among younger cases than among the older cases, and the fact indicates the good distensibility of the lung in younger patients.
Regardless of the grade of overdistension of the remaining lung, neither the vital capacity nor the total lung capacity showed increase after the operation. The residual volume in relation to the total lung capacity also revealed no significant difference according to the grade of overdistension. These facts show that the distension of the remaining lung is merely the morphological displacement of a part of the lung into the pneumonectomized space and is not accompanied with the increase in pulmonary function.
It was found that the alveolar ventilation was abnormally uneven in overdistended lung. In such lung, the volume of poorly ventilated area showed increase and the ventilation per unit of alveolar volume showed decrease, thus resulting in the definite arterial desaturatio n in some cases. The grade of such abnormalities, however, was less than that in chronic obstructive lung diseases. The arterial oxygen saturation was less than 92% in 2 of the study cases, and they were accompanied with either chronic obstructive emphysema or chronic bronchitis, which were presumed to be existing before operation.
No correlation was found between the grade of overd istension of the lung and the occurence of postoperative dyspnea.
In the majority of the cases, the arterial desaturation was improved after the resection of the diseased lung. The fact might be explained by the removal of venous admixture which existed in the resected lung.
