抄録
Twenty-one non-operated cases with pulmonary tuberculosis have been studied after their unilateral pulmonary artery had been temporarily occluded with a ballon catheter.
The results obtained were as follows;
1. Occlusion of the pulmonary artery results in a rise in proximal pulmonary artery pressure. When the non-occluded lung is slightly are not involved, the rise is scarcely observed.
The involvement of 2/3 the non-occluded lung area on roentogenogram is a maximal limit for occlusion for fear of fatality.
The blood pressure distal to occlusion immediately decreases nearly to wedge pressure level, and it shows a change from an arterial to a venous form.
2. Minute ventilation and oxygen consumption show an increase following occlusion. The increase is more marked in Group A in which the pulmonary artery in the morbid lung is occluded than in Group B in which the pulmonary artery in the less morbid other lung. It is to be noted that even the occluded lung shows a slight consumption of oxygen and a slight production of carbon dioxide.
Per cent vital capadity, per cent maximum breathing capacity, timed vital capacity, per one sec. and per cent vital capacity in the contralateral lung measured before occlusion decrease in far advanced cases under a mean pulmonary artery pressure of over 20 mmHg.
3. A slight decrease is observed in arterial oxygen saturation as well as in oxygen content during occlusion. The decrease is more marked in Group B than in Group A. The carbon dioxide content in the arterial blood during occlusion slightly increases.
The distal blood sample during pulmonary artery occlusion has a higher oxygen and lower carbon dioxide content than the systemic arterial blood sample.
A-V oxygen difference, total pulmonary vascular resistance and right ventricular work for pressure show an increase during occlusion. The increase is more marked in Group B than Group A. Cardiac index during occlusion increases or decreases depending upon individal cases.
4. Following occlusion the E C G findings have revealed that there occurs each one case of right bundle branch block and incomplete right bundle branch block among the 18 cases studied.
It is suggested that pulmonary artery occlusion results in an increase of work load of the right heart.
5. Unilateral pulmonary artery occlusion test seems to be required in deciding the indication for pulmonary resection especially for pneumonectomy, if the lesion is found in the contralateral lung, total per cent vital capacity is less than 60 % or vital capacity in the contralateral lung is less than 40%.
