Oxyhemoglobin Dissociation Curve and 2, 3-Diphosphoglycerate in Chronic Hypoxemia

• Published in: Nihon Kyōbu Shikkan Gakkai zasshi Vol. 29; no. 5; pp. 547 - 553
• Main Author: Koizumi, Makoto
• Format: Journal Article
• Language: Japanese
• Published: Japan The Japanese Respiratory Society 01.05.1991
• Subjects: 2,3-Diphosphoglycerate; Adult; Aged; Carbon Dioxide - blood; Chronic Disease; Chronic hypoxemia; Diphosphoglyceric Acids - blood; Humans; Hydrogen-Ion Concentration; Hypoxia - blood; Hypoxia - metabolism; Middle Aged; Oxygen - blood; Oxygen Consumption; Oxyhemoglobin dissociation curve; Oxyhemoglobins - metabolism; Partial Pressure
• ISSN: 0301-1542; 1883-471X
• DOI: 10.11389/jjrs1963.29.547

The measurement of the oxyhemoglobin dissociation curve (ODC) and 2, 3-diphosphoglycerate (2, 3-DPG) in patients with chronic hypoxemia is important from the view point of tissue oxygenation. However, there have been no consistent results that explain the relation among chronic hypoxemia, 2, 3-DPG and P50, which is oxygen pressure at an oxygen saturation of 50 percent. The aim of this study is to clarify what factors affect P50 and 2, 3-DPG. 1) Patients with chronic hypoxemia, who showed PaO2<60Torr, had significantly higher P50 than normal subjects. 2) The concentration of Hb showed significant negative correlation with both P50 and 2, 3-DPG. 3) Arterial blood pH showed significant positive correlation with both P50 and 2, 3-DPG. 4) In a group with normal levels of Hb and pH, there was significant negative relationship between PaO2 and P50. 5) In a group with normal levels of Hb and pH, there was significant positive relationship between PaCO2 and P50. 6) In a group with normal levels of Hb, pH and PaCO2, there was significant negative relationship between PaO2 and 2, 3-DPG. In conclusion, P50 and 2, 3-DPG are affected largely by Hb concentration or blood pH, with or without hypoxemia. However there is a mechanism by which P50 and 2, 3-DPG are increased by hypoxemia itself in a group with normal levels of Hb, pH and PaCO2.