Ventilatory response and arterial blood gases during exercise in children

H. Ohuchi et al., Ventilatory response and arterial blood gases during exercise in children, PEDIAT RES, 45(3), 1999, pp. 389-396
Citations number
Categorie Soggetti
Pediatrics,"Medical Research General Topics
Journal title
ISSN journal
0031-3998 → ACNP
Year of publication
389 - 396
SICI code
To investigate the difference in ventilatory response to exercise between c hildren and young adults, we administered a treadmill progressive exercise test to seven boys (aged 8 to 11 y [group A]) and six male young adults (ag ed 14 to 21 y [group B]), who had a history of Kawasaki disease without sig nificant coronary arterial lesions, and analyzed their arterial blood gases . There was no significant difference in arterial Po-2 or the end-tidal to arterial oxygen tension difference during exercise between groups A and B. The arterial Pco(2) (Paco(2)) at the ventilatory anaerobic threshold and at peak exercise was significantly lower in group A than in group B (p < 0.05 ). The arterial to end-tidal carbon dioxide tension difference at peak exer cise was significantly greater in group B than in group A (p < 0.05), where as there was no significant difference at rest or at the ventilatory anaero bic threshold level. The arterial to end-tidal carbon dioxide tension diffe rence at peak exercise was correlated with tidal volume p < 0.01) and carbo n dioxide production (p < 0.05) at peak exercise in all subjects. Although improvement in the physiologic dead space/tidal volume ratio during exercis e was smaller in group A than in group B, there was no significant differen ce in total alveolar ventilation during exercise. However, the total carbon dioxide production during exercise was significantly smaller in group A th an in group B. These data suggest that Paco(2) during exercise is better es timated by end-tidal carbon dioxide tension in children than in young adult s, that there is a significant difference in change of the Paco(2) during e xercise between children and young adults, and that the decrease in Paco(2) in children is related to the mismatch between well-maintained alveolar ve ntilation and immature metabolic development in the working muscles during moderate-to-severe exercise.