title: Influence of pulmonary blood flow on gas exchange in piglets.
abstract: We previously reported that O2 diffusion was limited in piglets. To test the hypothesis of an inadequacy between diffusion and perfusion in piglets (< 4 wk) vs. older pigs (> 8 wk), we compared in these two age groups the effect of an increase (by opening an arteriovenous fistula) or a decrease (by inflating a balloon in the inferior vena cava) in cardiac output (Q) on gas exchange and on the O2 equilibration coefficient D/Q beta [ratio of the diffusion capacity of O2 (D) to the product of Q and the capacitance coefficient of blood (beta)]. In piglets but not in older pigs, a decrease in Q improved the alveolar-arterial Po2 difference (P < 0.05) and D/Q beta (P < 0.05), whereas an increase in Q had the opposite effect. Changes in the alveolar-arterial O2 difference and D/Q beta were linearly correlated with Q (r = 0.75, P < 0.01 and r = 0.88, P < 0.01, respectively). We suggest that the impaired O2 diffusion in piglets was due to inadequate diffusion-perfusion equilibrium of O2.
authors.affiliation: Laboratoire de Chirurgie Expérimentale, Hôpital Marie-Lannelongue, Le Plessis Robinson, France.
authors.forename: P
authors.initials: P
authors.lastname: Escourrou
authors.forename: X
authors.initials: X
authors.lastname: Qi
authors.forename: M
authors.initials: M
authors.lastname: Weiss
authors.forename: G M
authors.initials: GM
authors.lastname: Mazmanian
authors.forename: C
authors.initials: C
authors.lastname: Gaultier
authors.forename: P
authors.initials: P
authors.lastname: Hervé
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D002302:Cardiac Output / Q000502:physiology; D004058:Diffusion; D010101:Oxygen Consumption; D011650:Pulmonary Alveoli / Q000378:metabolism; D011652:Pulmonary Circulation / Q000502:physiology*; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D013552:Swine