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Determination Of Pulmonary Parameters (V̇A, \( {D_{{L_{{O^2}}}}} \)) From Arterial O2 and CO2 Partial Pressures During Exercise

  • F. Mertzlufft
  • G. Thews
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 180)

Abstract

The arterial O2 and CO2 partial pressures mainly depend on the ventilation-perfusion ratio V̇A/Q̇ and on the O2 diffusing capacity-perfusion ratio DLO2/Q̇. According to RAHN’s V̇A/Q̇ concept, the dependence of the alveolar O2 and CO2 partial pressures on the ventilation-perfusion ratio can be determined graphically, and displayed in the form of a diagram (2,3). However, the application of the RAHN diagram is limited by the fact that during the passage of the blood through the lung capillaries, a complete adjustment of the capillary O2 partial pressure to the alveolar value frequently does not occur. This is particularly valid for gas exchange during exercise. For this case, the alveolar-endcapillary O2 partial pressure difference, PAO2 — PC’O2, can be calculated on the basis of an exponential increase of PO2 in the lung capillaries. The existence of such a course can be concluded from various theoretical and experimental results (1,5,6).

Keywords

Partial Pressure Bicycle Ergometer Base Excess Diffuse Capacity Alveolar Ventilation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Plenum Press, New York 1984

Authors and Affiliations

  • F. Mertzlufft
    • 1
  • G. Thews
    • 1
  1. 1.Department of PhysiologyUniversity of MainzMainzGermany

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