Determination of the Oxygen Affinity of Human Blood In Vivo and under Standard Conditions

Abstract

Determinations of hemoglobin oxygen saturation, oxygen tension, whole blood pH, carbon dioxide tension, red cell 2,3-diphosphoglycerate (DPG), and carboxy-hemoglobin concentration were carried out on venous blood from normal human subjects at rest. When the oxygen tension was calculated for the standard conditions of pH = 7.40, Pc₂ = 40 mm Hg, red cell DPG = 5.0 mmol/l, and HbCO = 1.0%, it was found that the individual points coin cided with cided with the standard oxygen dissociation curve as obtained by tonometry. The procedure can therefore be used to obtain a quantitative estimation of the oxygen affinity of whole blood in vivo as well as under standard conditions. The precision is such that a deviation from normality of about 2 mm Hg can be detected by a single determination.

Key Words:

• Blood oxygen affinity in vivo