Subscribe to RSS
DOI: 10.1055/s-0043-1771161
Blood Gas Transport: Implications for O2 and CO2 Exchange in Lungs and Tissues
![](https://www.thieme-connect.de/media/srccm/202305/lookinside/thumbnails/10-1055-s-0043-1771161_230506-1.jpg)
Abstract
The well-known ways in which O2 and CO2 (and other gases) are carried in the blood were presented in the preceding chapter. However, what the many available texts about O2 and CO2 transport do not emphasize is why knowing how gases are carried in blood matters, and this second, companion, article specifically addresses that critical aspect of gas exchange physiology. During gas exchange, both at the lungs and in the peripheral tissues, it is the shapes and the slopes of the O2 and CO2 binding curves that explain almost all of the behaviors of each gas and the quantitative differences observed between them. This conclusion is derived from first principle considerations of the gas exchange processes. Dissociation curve shape and slope differences explain most of the differences between O2 and CO2 in both diffusive exchange in the lungs and tissues and convective exchange/transport in, and between, the lungs and tissues. In fact, each of the chapters in this volume describes physiological behavior that depends more or less directly on the dissociation curves of O2 and CO2.
Keywords
inert gases - solubility - dissociation curves - diffusive gas exchange - convective gas transport - O2–CO2 interactionsPublication History
Article published online:
11 August 2023
© 2023. Thieme. All rights reserved.
Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA
-
References
- 1 Weibel ER. The Pathway for Oxygen: Structure and Function in the Mammalian Respiratory System. Cambridge Mass: Harvard University Press; 1984
- 2 Piiper J, Scheid P. Blood-gas equilibration in the lungs. In: J.B W. ed. Pulmonary Gas Exchange Volume 1. Ventilation, Blood Flow and Diffusion. new York, NY: Academic press; 1980: 131-173
- 3 Piiper J, Scheid P. Model for capillary-alveolar equilibration with special reference to O2 uptake in hypoxia. Respir Physiol 1981; 46 (03) 193-208
- 4 Piiper J, Scheid P. Comparison of diffusion and perfusion limitations in alveolar gas exchange. Respir Physiol 1983; 51 (03) 287-290
- 5 Piiper J, Scheid P. Diffusion limitation of O2 supply to tissue in homogeneous and heterogeneous models. Respir Physiol 1991; 85 (01) 127-136
- 6 Piiper J, Scheid P. Modeling oxygen availability to exercising muscle. Respir Physiol 1999; 118 (2-3): 95-101
- 7 Dempsey JA, Wagner PD. Exercise-induced arterial hypoxemia. J Appl Physiol 1999; 87 (06) 1997-2006
- 8 Wagner PD, Gale GE, Moon RE, Torre-Bueno JR, Stolp BW, Saltzman HA. Pulmonary gas exchange in humans exercising at sea level and simulated altitude. J Appl Physiol (1985) 1986; 61 (01) 260-270
- 9 Richardson RS, Noyszewski EA, Kendrick KF, Leigh JS, Wagner PD. Myoglobin O2 desaturation during exercise. Evidence of limited O2 transport. J Clin Invest 1995; 96 (04) 1916-1926
- 10 Andersen P, Saltin B. Maximal perfusion of skeletal muscle in man. J Physiol 1985; 366 (01) 233-249
- 11 Richardson RS, Grassi B, Gavin TP. et al. Evidence of O2 supply-dependent VO2 max in the exercise-trained human quadriceps. J Appl Physiol 1999; 86 (03) 1048-1053
- 12 Roca J, Hogan MC, Story D. et al. Evidence for tissue diffusion limitation of VO2max in normal humans. J Appl Physiol (1985) 1989; 67 (01) 291-299
- 13 Schmidt U. The solubility of carbon monoxide and hydrogen in water and sea-water at partial pressures of about 10-5 atmospheres. Tellus 1979; 31 (01) 68-74
- 14 Rahn H, Fenn WO. Graphical Analysis of the Respiratory Gas Exchange. Bethesda, MD: American Physiological Society; 1955
- 15 Riley RL, Cournand A. Analysis of factors affecting partial pressures of oxygen and carbon dioxide in gas and blood of lungs; theory. J Appl Physiol 1951; 4 (02) 77-101
- 16 Riley RL, Cournand A. Ideal alveolar air and the analysis of ventilation-perfusion relationships in the lungs. J Appl Physiol 1949; 1 (12) 825-847
- 17 Wagner PD, Malhotra A, Prisk GK. Using pulmonary gas exchange to estimate shunt and deadspace in lung disease: theoretical approach and practical basis. J Appl Physiol (1985) 2022; 132 (04) 1104-1113
- 18 Vogiatzis I, Habazettl H, Louvaris Z. et al. A method for assessing heterogeneity of blood flow and metabolism in exercising normal human muscle by near-infrared spectroscopy. J Appl Physiol (1985) 2015; 118 (06) 783-793