This Article Full Text Full Text (PDF) Online Supplement All Versions of this Article: 200406-707OCv1 171/1/83    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hopkins, S. R. Articles by Levin, D. L. Search for Related Content PubMed PubMed Citation Articles by Hopkins, S. R. Articles by Levin, D. L.

Pulmonary Blood Flow Heterogeneity during Hypoxia and High-Altitude Pulmonary Edema

Department of Medicine, Division of Physiology, and Department of Radiology, University of California, San Diego, La Jolla, California

Correspondence and requests for reprints should be addressed to Susan R. Hopkins, M.D., Ph.D., Department of Medicine, Division of Physiology 0623A, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093. E-mail: shopkins{at}ucsd.edu

Uneven hypoxic pulmonary vasoconstriction has been proposed to expose parts of the pulmonary capillary bed to high pressure and vascular injury in high-altitude pulmonary edema (HAPE). We hypothesized that subjects with a history of HAPE would demonstrate increased heterogeneity of pulmonary blood flow during hypoxia. A functional magnetic resonance imaging technique (arterial spin labeling) was used to quantify spatial pulmonary blood flow heterogeneity in three subject groups: (1) HAPE-susceptible (n = 5), individuals with a history of physician-documented HAPE; (2) HAPE-resistant (n = 6), individuals with repeated high-altitude exposure without illness; and (3) unselected (n = 6), individuals with a minimal history of altitude exposure. Data were collected in normoxia and after 5, 10, 20, and 30 minutes of normobaric hypoxia . Relative dispersion (SD/mean) of the signal intensity was used as an index of perfusion heterogeneity. Oxygen saturation was not different between groups during hypoxia. Relative dispersion was not different between groups (HAPE-susceptible 0.94 ± 0.05, HAPE-resistant 0.94 ± 0.05, unselected 0.87 ± 0.06; means ± SEM) during normoxia, but it was increased by hypoxia in HAPE-susceptible (to 1.10 ± 0.05 after 30 minutes, p < 0.0001) but not in HAPE-resistant (0.91 ± 0.05) or unselected subjects (0.87 ± 0.05). HAPE-susceptible individuals have increased pulmonary blood flow heterogeneity in acute hypoxia, consistent with uneven hypoxic pulmonary vasoconstriction.

Key Words: hypoxic pulmonary vasoconstriction • magnetic resonance imaging • pulmonary circulation

This article has been cited by other articles:

				S. Sarada, P. Himadri, C. Mishra, P. Geetali, M. S. Ram, and G. Ilavazhagan Role of Oxidative Stress and NFkB in Hypoxia-Induced Pulmonary Edema Experimental Biology and Medicine, September 1, 2008; 233(9): 1088 - 1098. [Abstract] [Full Text] [PDF]

				R. B. Schoene Illnesses at High Altitude Chest, August 1, 2008; 134(2): 402 - 416. [Abstract] [Full Text] [PDF]

				P. Bartsch and J. S. R. Gibbs Effect of Altitude on the Heart and the Lungs Circulation, November 6, 2007; 116(19): 2191 - 2202. [Full Text] [PDF]

				J. T. Berg Chronic hypoxia-induced pulmonary hypertension does/does not lead to loss of pulmonary vasculature J Appl Physiol, October 1, 2007; 103(4): 1455 - 1455. [Full Text] [PDF]

				G. K. Prisk, K. Yamada, A. C. Henderson, T. J. Arai, D. L. Levin, R. B. Buxton, and S. R. Hopkins Pulmonary perfusion in the prone and supine postures in the normal human lung J Appl Physiol, September 1, 2007; 103(3): 883 - 894. [Abstract] [Full Text] [PDF]

				S. R. Hopkins, A. C. Henderson, D. L. Levin, K. Yamada, T. Arai, R. B. Buxton, and G. K. Prisk Vertical gradients in regional lung density and perfusion in the supine human lung: the Slinky effect J Appl Physiol, July 1, 2007; 103(1): 240 - 248. [Abstract] [Full Text] [PDF]

				D. L. Levin, R. B. Buxton, J. P. Spiess, T. Arai, J. Balouch, and S. R. Hopkins Effects of age on pulmonary perfusion heterogeneity measured by magnetic resonance imaging J Appl Physiol, May 1, 2007; 102(5): 2064 - 2070. [Abstract] [Full Text] [PDF]

				S. R. Hopkins, D. L. Levin, K. Emami, S. Kadlecek, J. Yu, M. Ishii, and R. R. Rizi Advances in magnetic resonance imaging of lung physiology J Appl Physiol, March 1, 2007; 102(3): 1244 - 1254. [Abstract] [Full Text] [PDF]

				L. J. Teppema, G. M. Balanos, C. D. Steinback, A. D. Brown, G. E. Foster, H. J. Duff, R. Leigh, and M. J. Poulin Effects of Acetazolamide on Ventilatory, Cerebrovascular, and Pulmonary Vascular Responses to Hypoxia Am. J. Respir. Crit. Care Med., February 1, 2007; 175(3): 277 - 281. [Abstract] [Full Text] [PDF]

				E. M. Snyder, K. C. Beck, M. L. Hulsebus, J. F. Breen, E. A. Hoffman, and B. D. Johnson Short-term hypoxic exposure at rest and during exercise reduces lung water in healthy humans J Appl Physiol, December 1, 2006; 101(6): 1623 - 1632. [Abstract] [Full Text] [PDF]

				C. Dehnert, F. Risse, S. Ley, T. A. Kuder, R. Buhmann, M. Puderbach, E. Menold, D. Mereles, H.-U. Kauczor, P. Bartsch, et al. Magnetic Resonance Imaging of Uneven Pulmonary Perfusion in Hypoxia in Humans Am. J. Respir. Crit. Care Med., November 15, 2006; 174(10): 1132 - 1138. [Abstract] [Full Text] [PDF]

				M. Maggiorini, H.-P. Brunner-La Rocca, S. Peth, M. Fischler, T. Bohm, A. Bernheim, S. Kiencke, K. E. Bloch, C. Dehnert, R. Naeije, et al. Both tadalafil and dexamethasone may reduce the incidence of high-altitude pulmonary edema: a randomized trial. Ann Intern Med, October 3, 2006; 145(7): 497 - 506. [Abstract] [Full Text] [PDF]

				E. R. Swenson Hypoxic lung whiteout: further clearing but more questions from on high. Ann Intern Med, October 3, 2006; 145(7): 550 - 552. [Full Text] [PDF]

				E. K. Weir and A. Olschewski Role of ion channels in acute and chronic responses of the pulmonary vasculature to hypoxia Cardiovasc Res, September 1, 2006; 71(4): 630 - 641. [Abstract] [Full Text] [PDF]

				A. C. Henderson, D. L. Levin, S. R. Hopkins, I. M. Olfert, R. B. Buxton, and G. K. Prisk Steep head-down tilt has persisting effects on the distribution of pulmonary blood flow J Appl Physiol, August 1, 2006; 101(2): 583 - 589. [Abstract] [Full Text] [PDF]

				M. Dehler, E. Zessin, P. Bartsch, and H. Mairbaurl Hypoxia causes permeability oedema in the constant-pressure perfused rat lung. Eur. Respir. J., March 1, 2006; 27(3): 600 - 606. [Abstract] [Full Text] [PDF]

				M. M. Hoeper and L. J. Rubin Update in pulmonary hypertension 2005. Am. J. Respir. Crit. Care Med., March 1, 2006; 173(5): 499 - 505. [Full Text] [PDF]

				M. W. Eldridge, R. K. Braun, K. Y. Yoneda, and W. F. Walby Effects of altitude and exercise on pulmonary capillary integrity: evidence for subclinical high-altitude pulmonary edema J Appl Physiol, March 1, 2006; 100(3): 972 - 980. [Abstract] [Full Text] [PDF]

				M. M. Berger, C. Hesse, C. Dehnert, H. Siedler, P. Kleinbongard, H. J. Bardenheuer, M. Kelm, P. Bartsch, and W. E. Haefeli Hypoxia Impairs Systemic Endothelial Function in Individuals Prone to High-Altitude Pulmonary Edema Am. J. Respir. Crit. Care Med., September 15, 2005; 172(6): 763 - 767. [Abstract] [Full Text] [PDF]