Journal of Applied Physiology, Vol 66, Issue 4 1570-1578, Copyright © 1989 by American Physiological Society

ARTICLES

Effect of cardiac output on gravity-dependent and nondependent inequality in pulmonary blood flow

T. S. Hakim, R. Lisbona and G. W. Dean
Department of Surgery, State University of New York Health Science Center, Syracuse 13210.

To examine the effect of cardiac output (CO) on the gravity-nondependent distribution of pulmonary blood flow, 2 X 10(6) 99mTc-labeled albumin microspheres (20 microns) were injected at end expiration into dogs (anesthetized, supine, and breathing room air spontaneously). Two animals were injected at their resting CO, two were injected during increased CO (arteriovenous fistulas induced), and two were injected at low CO (phlebotomy induced). The chest was opened and the lungs were removed, drained of blood, and dried while fully inflated. Single-photon emission-computed tomography was performed on the dry lungs to map the distribution of activity in transverse, coronal, and sagittal slices. The results confirmed the presence of a central-peripheral gravity-nondependent gradient and showed that increases in CO were associated with increases in absolute flow to both the central and peripheral regions of the lung with persistence of the central-peripheral gradient. These observations were further confirmed by direct imaging of midcoronal slices. Examination of the average flow in vertical and horizontal slices showed that, when zone 1 was not present, changes in CO affected all slices uniformly, such that when the CO doubled, the absolute flow in every slice in all three planes also doubled. We conclude that, with the exception of recruitment and derecruitment of vascular channels in the upper regions of the lung (zone 1), when CO changes, the blood flow everywhere in the lung changes uniformly and in proportion to the CO. This uniform increase in blood flow is consistent with the three-dimensional nature and resistive properties of the pulmonary vascular tree.

This article has been cited by other articles:

				J. Petersson, A. Sanchez-Crespo, S. A. Larsson, and M. Mure Physiological imaging of the lung: single-photon-emission computed tomography (SPECT) J Appl Physiol, January 1, 2007; 102(1): 468 - 476. [Abstract] [Full Text] [PDF]

				D. Chon, K. C. Beck, R. L. Larsen, H. Shikata, and E. A. Hoffman Regional pulmonary blood flow in dogs by 4D-X-ray CT J Appl Physiol, November 1, 2006; 101(5): 1451 - 1465. [Abstract] [Full Text] [PDF]

				G. Tusman, M. Areta, C. Climente, R. Plit, F. Suarez-Sipmann, M. J. Rodriguez-Nieto, G. Peces-Barba, E. Turchetto, and S. H. Bohm Effect of pulmonary perfusion on the slopes of single-breath test of CO2 J Appl Physiol, August 1, 2005; 99(2): 650 - 655. [Abstract] [Full Text] [PDF]

				S. Montmerle, P. Sundblad, and D. Linnarsson Residual heterogeneity of intra- and interregional pulmonary perfusion in short-term microgravity J Appl Physiol, June 1, 2005; 98(6): 2268 - 2277. [Abstract] [Full Text] [PDF]

				G. S. Krenz and C. A. Dawson Flow and pressure distributions in vascular networks consisting of distensible vessels Am J Physiol Heart Circ Physiol, June 1, 2003; 284(6): H2192 - H2203. [Abstract] [Full Text] [PDF]

				J. E. Souders, J. B. Doshier, N. L. Polissar, and M. P. Hlastala Spatial distribution of venous gas emboli in the lungs J Appl Physiol, November 1, 1999; 87(5): 1937 - 1947. [Abstract] [Full Text] [PDF]

				C. M. Mann, K. B. Domino, S. M. Walther, R. W. Glenny, N. L. Polissar, and M. P. Hlastala Redistribution of pulmonary blood flow during unilateral hypoxia in prone and supine dogs J Appl Physiol, June 1, 1998; 84(6): 2010 - 2019. [Abstract] [Full Text] [PDF]

				M. Kleen, O. Habler, J. Hutter, G. Kemming, A. Podtschaske, M. Tiede, M. Welte, P. E. Keipert, S. Batra, N. S. Faithfull, et al. Hemodilution and hyperoxia locally change distribution of regional pulmonary perfusion in dogs Am J Physiol Heart Circ Physiol, February 1, 1998; 274(2): H520 - H528. [Abstract] [Full Text] [PDF]

				J. C. Parker, C. B. Cave, J. L. Ardell, C. R. Hamm, and S. G. Williams Vascular tree structure affects lung blood flow heterogeneity simulated in three dimensions J Appl Physiol, October 1, 1997; 83(4): 1370 - 1382. [Abstract] [Full Text] [PDF]

				S. M. Walther, K. B. Domino, R. W. Glenny, N. L. Polissar, and M. P. Hlastala Pulmonary blood flow distribution has a hilar-to-peripheral gradient in awake, prone sheep J Appl Physiol, February 1, 1997; 82(2): 678 - 685. [Abstract] [Full Text] [PDF]