Journal of Applied Physiology, Vol 53, Issue 4 992-1004, Copyright © 1982 by American Physiological Society

ARTICLES

Lung fluid balance in lambs before and after birth

R. D. Bland, T. N. Hansen, C. M. Haberkern, M. A. Bressack, T. A. Hazinski, J. U. Raj and R. B. Goldberg

To study lung fluid balance before and after birth, we measured lung lymph flow and concentrations of protein in lymph and plasma of 22 unanesthetized fetal lambs and compared results with previous studies done on 26 newborn lambs, 1-2 wk old. Lymph flow, relative to lung mass, was less in fetuses than in newborns; lymph protein clearance was not significantly different. Less lymph flow before birth probably reflects less available surface area for fluid exchange in microcirculation of fetal lungs, compared with newborn lungs, with no difference in endothelial permeability to protein. Extravascular lung water, measured gravimetrically for 24 fetuses (10 without labor, nine in labor, five 6 h after vaginal birth), decreased by 45% (15 +/- 2 g/kg body wt) before birth and by an additional 38% (6 +/- 1 g/kg) after birth. In five lambs killed after birth, we measured lung lymph flow before and during labor and for 6 h after breathing began. Lymph flow was unaffected by labor but increased transiently after birth, accounting for 11% of the liquid removed from lungs postnatally. Liquid clearance studies performed in eight anesthetized 3-wk-old lambs confirmed the observation that lung lymphatics drain only a small fraction of liquid in potential air spaces. Most of that liquid probably leaves the lungs directly through pulmonary circulation.

This article has been cited by other articles:

				N. Elias, B. Rafii, M. Rahman, G. Otulakowski, E. Cutz, and H. O'Brodovich The role of {alpha}-, beta-, and {gamma}-ENaC subunits in distal lung epithelial fluid absorption induced by pulmonary edema fluid Am J Physiol Lung Cell Mol Physiol, September 1, 2007; 293(3): L537 - L545. [Abstract] [Full Text] [PDF]

				N. Elias and H. O'Brodovich Clearance of Fluid From Airspaces of Newborns and Infants NeoReviews, February 1, 2006; 7(2): e88 - e94. [Full Text] [PDF]

				R. C. Dukarm, R. H. Steinhorn, J. A. Russell, S. Lakshminrusimha, D. Swartz, and J. J. Cummings Selective type 5 phosphodiesterase inhibition alters pulmonary hemodynamics and lung liquid production in near-term fetal lambs J Appl Physiol, December 1, 2005; 99(6): 2331 - 2336. [Abstract] [Full Text] [PDF]

				R. D. Bland Lung Fluid Balance During Development NeoReviews, June 1, 2005; 6(6): e255 - e267. [Full Text] [PDF]

				K. E. WILLET, A. H. JOBE, M. IKEGAMI, J. KOVAR, and P. D. SLY Lung Morphometry after Repetitive Antenatal Glucocorticoid Treatment in Preterm Sheep Am. J. Respir. Crit. Care Med., May 1, 2001; 163(6): 1437 - 1443. [Abstract] [Full Text]

				J. J. Cummings and H. Wang Nitric oxide decreases lung liquid production via guanosine 3',5'-cyclic monophosphate Am J Physiol Lung Cell Mol Physiol, May 1, 2001; 280(5): L923 - L929. [Abstract] [Full Text] [PDF]

				R. D. Bland Loss of liquid from the lung lumen in labor: more than a simple "squeeze" Am J Physiol Lung Cell Mol Physiol, April 1, 2001; 280(4): L602 - L605. [Full Text] [PDF]

				A. Norlin and H. G. Folkesson Alveolar fluid clearance in late-gestational guinea pigs after labor induction: mechanisms and regulation Am J Physiol Lung Cell Mol Physiol, April 1, 2001; 280(4): L606 - L616. [Abstract] [Full Text] [PDF]

				J. J. Cummings Nitric oxide decreases lung liquid production in fetal lambs J Appl Physiol, November 1, 1997; 83(5): 1538 - 1544. [Abstract] [Full Text] [PDF]

				D. P. Carlton, K. H. Albertine, S. C. Cho, M. Lont, and R. D. Bland Role of neutrophils in lung vascular injury and edema after premature birth in lambs J Appl Physiol, October 1, 1997; 83(4): 1307 - 1317. [Abstract] [Full Text] [PDF]

				A. Lines, S. B. Hooper, and R. Harding Lung liquid production rates and volumes do not decrease before labor in healthy fetal sheep J Appl Physiol, March 1, 1997; 82(3): 927 - 932. [Abstract] [Full Text] [PDF]