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Relation between the Contact Time and Venous and Alveolar Pco2 at Rest

  • Masaji Mochizuki
  • Tomoko Kagawa
  • Katsuo Uchida
  • Izumi Shibuya
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 200)

Abstract

The simultaneous partial differential equations for diffusions of O2, CO2, and HCO 3 ions in the red blood cell (RBC) were solved numerically, taking chemical reactions of Bohr- and Haldane-effects into account. The diffusion equations and the chemical reactions were computed alternatively in an increment time of 2 msec. After solving each of the three diffusion equations, the Po2, O2 saturation (S), Pco2, pH and HCO 3 content were corrected by using the equations of Bohr- and Haldane-effects, and a modified Henderson-Hasselbalch equation (Kagawa and Mochizuki, 1984). The Bohr-shift was calculated from Hill’s equation by assuming its K value to be a function of the intracellular pH. The change in intracellular Pco2 due to the Haldane effect was also evaluated by means of the modified Henderson-Hasselbalch equation, in which the buffer value was taken as 44 mmol · 1(RBC)−1 · pH c −1 . The computed Pco2 profiles during the Haldane effect in a closed vessel was compatible wit the experimental data of Klocke (1973). The extracellular Po2 profile computed during the Bohr-off-shift in a closed system coincided well with the experimental data of Nakamura and Staub (1964) and Forster and Steen (1968).

Keywords

Contact Time Diffusion Equation Rebreathing Method Lung Capillary Pulmonary Capillary Blood 
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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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Masaji Mochizuki
    • 1
  • Tomoko Kagawa
    • 1
  • Katsuo Uchida
    • 1
  • Izumi Shibuya
    • 1
  1. 1.Department of PhysiologyYamagata University School of MedicineYamagataJapan

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