Cardiogenic oscillations of He and SF6 in expired gas in dogs.
Quantitative analysis of cardiogenic oscillations of He and SF6 during airway and venous loading demonstrated that both VA/Q and VA/VA inequalities were involved in the lung gas inhomogeneity producing cardiac oscillations in the expirogram. Both inequalities were coupled in such a manner that low VA/Q units had high VA/VA. The oscillations were modified in conducting airways where SF6 oscillations were attenuated more than He oscillations, probably by laminar Taylor dispersion.
Meyer
M
M
Department of Physiology, Max Planck Institute for Experimental Medicine, Göttingen, Federal Republic of Germany.
Lewis
S M
SM
Mohr
M
M
Schulz
H
H
Schuster
K D
KD
Piiper
J
J
D000818:Animals; D004058:Diffusion; D004285:Dogs; D006321:Heart / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006371:Helium; D008954:Models, Biological; D009200:Myocardial Contraction / Q000502:physiology; D010507:Periodicity; D011659:Pulmonary Gas Exchange / Q000502:physiology; D015656:Respiratory Mechanics / Q000502:physiology*; D013459:Sulfur Hexafluoride
D006371:Helium; D013459:Sulfur Hexafluoride