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Updated: Aug 18, 2026

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
[Ventilatory and cardio-respiratory responses during exercise in chronic pulmonary restrictive disease (author's
Abstract:
Cardio-respiratory changes were studied during light exercise (20 or 40 W) in 45 patients with diminished vital total lung capacity. Diagnosis was : fibrosis (8 subjects, group I), lobectomy (7 subjects, group II), pachypleuritis (11 subjects, group III), thoracoplasty (7 subjects, group IV) and kyphoscoliosis (12 subjects, group V). Changes during exercise were characterized by : an increase in breathing rate much more marked than normally, with a lesser increase in tidal volume, so that ventilatory equivalent was steady, and below 30 except in group I; an increase in PaCO2, even in group I which was hypocapnic at rest, very marked in groups III and V, with worsening of hypoxemia in most cases; and enhancement of pulmonary artery hypertension, severe at rest already in group I.
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