[Pulmonary hemodynamics during exercise in anesthetized dogs with inspiratory loading and in patients with chronic obstructive pulmonary disease].
We studied 1) the effects of inspiratory elastic loading on pulmonary hemodynamics and pulmonary gas exchange with and without electrically induced hindlimb exercise in 8 anesthetized dogs, 2) pulmonary hemodynamics at rest and during single stage exercise on a supine cycle ergometer in 6 patients with chronic obstructive pulmonary disease (COPD) and 3) changes in P wave height in lead II of electrocardiogram during progressive exercise on a treadmill in 9 COPD patients. The pulmonary arterial pressure-flow relationship from resting to exercise was not affected by inspiratory elastic loading, but elastic loading accompanied by exercise increased alveolar-arterial O2 tension difference (AaDO2). The pulmonary arterial pressure-flow relationship in COPD from rest to exercise showed higher pulmonary vascular resistance than that in control group. Moreover, we found a greater increase in P wave height during exercise in COPD with decrease in PaO2 during exercise than in COPD without decrease in PaO2 during exercise. This increase in P wave height during exercise was inhibited by oxygen inhalation. We speculated that 1) increased AaDO2 during exercise with elastic loading may be due to increased shunt effects with low ventilation-perfusion ratio and 2) increased P wave height during exercise in COPD may be correlated with hypoxia during exercise and may be useful to detect latent cor pulmonale in COPD.
Hida
W
W
Taguchi
O
O
Chonan
T
T
Kikuchi
Y
Y
Ogata
M
M
Shirato
K
K
Takishima
T
T
D000368:Aged; D000818:Animals; D004285:Dogs; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011652:Pulmonary Circulation; D011659:Pulmonary Gas Exchange