[Investigation of pulmonary hemodynamics and chest X-ray findings in hypercapnic patients with pulmonary tuberculosis sequelae].
We investigated pulmonary hemodynamics and chest X-ray findings to explore pathophysiological significance of chronic hypercapnia in patients with pulmonary tuberculosis sequelae. One hundred and seven patients underwent examinations of blood gases and right cardiac catheterization. The patients were divided into two groups, according to arterial carbon dioxide tension under room air breathing (PaCO2). Group I (n = 35) was defined as 45 Torr or lower of PaCO2, and Group II (n = 72) was the hypercapnic group whose PaCO2 was over 45 Torr. In addition, spirometry was done in 34 patients of Group I and 68 of Group II. First, the values of blood gases, spirometry and pulmonary hemodynamics were compared between the two groups. Secondly, between 22 of Group I and 50 of Group II, the values of pulmonary arteriolar resistance (PAR) before and after 100% oxygen breathing for 10 minutes were compared. These comparisons were made by exploratory data analysis. Lastly, we described in all cases with five items of chest X-ray findings and the extent of each finding we had defined. The items were emphysematous change; fibrosis, bronchiectasis, and/or cavity (hereafter abbreviated as "fibrosis"); lung resection and/or atelectasis; pleural thickening; and thoracoplasty. We explored the items of X-ray findings which may relate to hypercapnia by ridit (abbreviation for "relative to an identified distribution") analysis. The results were as follows. (1) Hypercapnic patients tended to have severer restrictive ventilatory impairment and hypoxemia. Under an even level of arterial oxygen tension (PaO2), tissue oxygenation was not poorer in Group II than in Group I. (2) Hypercapnic patients tended to have more unfavorable pulmonary hemodynamics. More than half of them had pulmonary hypertension defined as 20 mmHg or higher of pulmonary artery mean pressure (PAm). Under an even level of PaO2, PAm was higher in Group II. Although 34 patients of Group II showed PaO2 over 60 Torr, 23 of them had pulmonary hypertension. (3) PAR after oxygen breathing was more likely to decrease in Group II than in Group I. (4) As any mean ridit was standardized and adjusted to 0.5 in Group I, the maximum was the mean ridit of "pleural thickening" (= 0.67), next "fibrosis" (= 0.65) in Group II. The above two items of X-ray findings, in which each mean ridit was higher than in any other item, were more influential on hypercapnia. We conclude as follows. (1) Pulmonary hypertension is severer in hypercapnic patients with pulmonary tuberculosis sequelae; it may be mainly attributable to hypoxic pulmonary vasoconstriction. (2) An important cause of chronic hypercapnia may be pathological changes such as "pleural thickening" and "fibrosis" seen on the radiogram.
Yasuda
J
J
Department of Chest Medicine, School of Medicine, Chiba University, Japan.
Okada
O
O
Kuriyama
T
T
Nagao
K
K
Yamagishi
F
F
Hashizume
I
I
Suzuki
A
A
D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010313:Partial Pressure; D011652:Pulmonary Circulation; D013902:Radiography, Thoracic; D014397:Tuberculosis, Pulmonary / Q000150:complications*
D002245:Carbon Dioxide