Abstract SINCE the original report by von Euler and Liljestrand, in 1946, which showed that acute hypoxia increased pulmonary vascular resistance,1 a number of studies in normal subjects have demonstrated the effects of acute hypoxia on pulmonary arterial pressure.2 In most studies 10% oxygen was used resulting in a decrease in arterial oxygen saturation to 75% to 85%. In spite of this severe hypoxic stimulus, mean pulmonary arterial pressure increased but 4 to 8 mm mercury (Hg).2 By contrast, in the subject with a hyperreactive pulmonary vascular bed, maintained by chronic hypoxia, increased pulmonary blood flow, or pulmonary venous hypertension, considerably greater increases in pulmonary arterial pressure have been noted with acute hypoxia. Thus, in a study of high-altitude subjects, ages 13 to 17 years, exposed to the chronic hypoxia of Leadville, Col at 10,150 feet, mean pulmonary arterial pressures increased by as much as 38 mm Hg References 1. Von Euler, U.S., and Liljestrand, G.: Observations on the Pulmonary Arterial Blood Pressure in the Cat , Acta Physiol Scand 12:301, 1946.Crossref 2. Fishman, A.P.: Respiratory Gases in the Regulation of the Pulmonary Circulation , Physiol Rev 41:214, 1961. 3. Vogel, J.H., et al: Pulmonary Hypertension on Exertion in Normal Man Living at 10,150 Feet (Leadville, Col) , Med Thorac 19:461, 1962. 4. Vogel, J.H., et al: Experimental Pulmonary Arterial Hypertension in the Newborn Calf , Cir Res 13:557, 1963.Crossref 5. Grover, R.F., et al: Pulmonary Vasoconstriction in Steers at High Altitude , J Appl Physiol 18:567, 1963. 6. Enson, Y., et al: The Influence of Hydrogen Ion Concentration and Hypoxia on the Pulmonary Circulation , J Clin Invest 43:1146, 1964.Crossref 7. Vogel, J.H., and Blount, S.G., Jr.: The Role of Hydrogen Ion Concentration in the Regulation of Pulmonary Arterial Pressure: Observations in a Patient With Hypoventilation and Obesity , Circulation 32:788, 1965.Crossref 8. Robin, E.D., et al: Alveolar Gas Tensions, Pulmonary Ventilation, and Blood pH During Physiologic Sleep in Normal Subjects , J Clin Invest 37:981, 1958.Crossref 9. Buhlmann, A., and Hossli, G.: Hamodynamische untersuchungen bei akuter hypoventilation , Schweiz Med Weschr 86:681, 1956. 10. Lloyd, T.C., Jr.: Influence of Blood pH on Hypoxic Pulmonary Vasoconstriction , J Appl Physiol 21:358, 1966. 11. Vogel, J.H.; Kelminson, L.L.; and Cotton, E.K.: Prolonged Observation of Pulmonary Arterial Pressure , Amer Heart J 70:429, 1965.Crossref 12. Vogel, J.H.; McNamara, D.G.; and Blount, S.G., Jr.: The Role of Hypoxia in Determining Pulmonary Vascular Resistance in Infants With Ventricular Septal Defects, Amer J Cardiol, to be published.
American Journal of Diseases of Children – American Medical Association
Published: May 1, 1967