The Effect of Blood O2 Affinity on the Efficiency of O2 Transport in Blood at Hypoxic Hypoxia
During delivery of O2 to the tissue, O2 partial pressure and content decrease, these two being related by the blood O2 dissociation curve (ODC) with O2 content rather than saturation plotted against PO2. When dealing with the O2 transport in the whole body, the PO2 decrement during transport in blood equals the difference between PO2 of the blood leaving the lung capillaries and that of the mixed-venous blood entering the lung. At hypoxic hypoxia this PO2 decrement becomes less than at normoxia, even though the total flux (O2 consumption) usually remains the same. A decrease of the pressure difference at unchanged O2 flux suggests that at hypoxia hypoxia the resistance to the O2 transport in blood must decrease, i.e., the O2 conductance must increase.
KeywordsCardiac Output Dissociation Curve Oxygen Affinity Mild Hypoxia Capacitance Coefficient
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