| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Unit of Critical Care and 2 Department of Imaging, National Heart and Lung Institute, Imperial College School of Medicine, Royal Brompton Hospital, London SW3 6NP, United Kingdom
Acute respiratory distress syndrome is characterized by alterations in the ventilation-perfusion ratio. Present techniques for studying regional pulmonary perfusion are difficult to apply in the critically ill. Electron-beam computed tomography was used to study the effects of prone positioning on regional pulmonary perfusion in six healthy subjects. Contrast-enhanced sections were obtained sequentially in the supine, prone, and (original) supine positions at full inspiration. Regions of interest were placed along the nondependent to dependent axis and relative perfusion calculated. When corrected for the redistribution of lung parenchyma, a gravitational gradient of pulmonary perfusion existed in both supine and prone positions. The distribution of perfusion between the supine or prone positions did not differ, but data analysis using smaller regions of interest demonstrated marked heterogeneity of perfusion between anatomically adjacent regions of lung. The distribution of lung parenchyma was more uniform in the prone position. Gravity was estimated to be responsible for 22-34% of perfusion heterogeneity in the supine and 27-41% in the prone positions. These data support the hypothesis that factors other than gravity may be at least as important in determining the distribution of pulmonary perfusion in humans. The influence of nongravitational factors may not be detectable if techniques that sample large tissue volumes are employed.
physiology; normal individuals; repositioning
This article has been cited by other articles:
|
|
 |
|
  T. J. Arai, A. C. Henderson, D. J. Dubowitz, D. L. Levin, P. J. Friedman, R. B. Buxton, G. K. Prisk, and S. R. Hopkins Hypoxic pulmonary vasoconstriction does not contribute to pulmonary blood flow heterogeneity in normoxia in normal supine humans J Appl Physiol, April 1, 2009; 106(4): 1057 - 1064. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K.S Burrowes, A.J Swan, N.J Warren, and M.H Tawhai Towards a virtual lung: multi-scale, multi-physics modelling of the pulmonary system Phil Trans R Soc A, September 28, 2008; 366(1879): 3247 - 3263. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Glenny Counterpoint: Gravity is not the major factor determining the distribution of blood flow in the healthy human lung J Appl Physiol, May 1, 2008; 104(5): 1533 - 1535. [Full Text] [PDF]
|
|
|
|
|
|
P. D. Wagner, W. W. Wagner Jr., S. R. Hopkins, G. K. Prisk, K. S. Burrowes, and M. H. Tawhai Point:Counterpoint: Gravity is/is not the major factor determining the distribution of blood flow in the human lung. J Appl Physiol, May 1, 2008; 104(5): 1537 - 1538. [Full Text] [PDF]
|
|
|
|
|
|
M. Hughes and J. B. West Point:Counterpoint: Gravity is/is not the major factor determining the distribution of blood flow in the human lung J Appl Physiol, May 1, 2008; 104(5): 1531 - 1533. [Full Text] [PDF]
|
|
|
|
 |
|
 H. Edgcombe, K. Carter, and S. Yarrow Anaesthesia in the prone position Br. J. Anaesth., February 1, 2008; 100(2): 165 - 183. [Abstract] [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]
|
|
|
|
|
|
I. Galvin, G. B. Drummond, and M. Nirmalan Distribution of blood flow and ventilation in the lung: gravity is not the only factor Br. J. Anaesth., April 1, 2007; 98(4): 420 - 428. [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]
|
|
|
|
|
|
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]
|
|
|
|
 |
|
 A. Vonk-Noordegraaf, S. A. van Wolferen, J. T. Marcus, A. Boonstra, P. E. Postmus, J. W. L. Peeters, and A. J. Peacock Noninvasive assessment and monitoring of the pulmonary circulation Eur. Respir. J., April 1, 2005; 25(4): 758 - 766. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. A. J. Hoste, C. D. V. K. Roosens, S. Bracke, J. M. A. Decruyenaere, D. D. Benoit, K. H. D. K. Vandewoude, and F. A. Colardyn Acute Effects of Upright Position on Gas Exchange in Patients With Acute Respiratory Distress Syndrome J Intensive Care Med, January 1, 2005; 20(1): 43 - 49. [Abstract] [PDF]
|
|
|
|
|
|
G. Peces-Barba, M. J. Rodriguez-Nieto, S. Verbanck, M. Paiva, and N. Gonzalez-Mangado Lower pulmonary diffusing capacity in the prone vs. supine posture J Appl Physiol, May 1, 2004; 96(5): 1937 - 1942. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. C. Sundar, J. Zaumseil, V. Podzorov, E. Menard, R. L. Willett, T. Someya, M. E. Gershenson, and J. A. Rogers Elastomeric Transistor Stamps: Reversible Probing of Charge Transport in Organic Crystals Science, March 12, 2004; 303(5664): 1644 - 1646. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Petersson, A. Sanchez-Crespo, M. Rohdin, S. Montmerle, S. Nyren, H. Jacobsson, S. A. Larsson, S. G. E. Lindahl, D. Linnarsson, R. W. Glenny, et al. Physiological evaluation of a new quantitative SPECT method measuring regional ventilation and perfusion J Appl Physiol, March 1, 2004; 96(3): 1127 - 1136. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A.T. Jones, D.M. Hansell, and T.W. Evans Quantifying pulmonary perfusion in primary pulmonary hypertension using electron-beam computed tomography Eur. Respir. J., February 1, 2004; 23(2): 202 - 207. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Won, D. Chon, J. Tajik, B. Q. Tran, G. B. Robinswood, K. C. Beck, and E. A. Hoffman CT-based assessment of regional pulmonary microvascular blood flow parameters J Appl Physiol, June 1, 2003; 94(6): 2483 - 2493. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A.T. Jones, D.M. Hansell, and T.W. Evans Pulmonary perfusion quantified by electron-beam computed tomography: effects of hypoxia and inhaled NO Eur. Respir. J., May 1, 2003; 21(5): 855 - 861. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Musch, J. D. H. Layfield, R. S. Harris, M. F. V. Melo, T. Winkler, R. J. Callahan, A. J. Fischman, and J. G. Venegas Topographical distribution of pulmonary perfusion and ventilation, assessed by PET in supine and prone humans J Appl Physiol, November 1, 2002; 93(5): 1841 - 1851. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J J Cordingley and B F Keogh The pulmonary physician in critical care {middle dot} 8: Ventilatory management of ALI/ARDS Thorax, August 1, 2002; 57(8): 729 - 734. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Rodriguez-Nieto, G. Peces-Barba, N. Gonzalez Mangado, M. Paiva, and S. Verbanck Similar ventilation distribution in normal subjects prone and supine during tidal breathing J Appl Physiol, February 1, 2002; 92(2): 622 - 626. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
