Journal of Applied Physiology, Vol 59, Issue 2 521-527, Copyright © 1985 by American Physiological Society
Distortion of submerged dog lung lobes
L. E. Olson, T. A. Wilson and J. R. Rodarte
The conically shaped caudal lobes of dog lungs were submerged, tip downward
in saline, and the lateral surfaces of the lobes were thereby exposed to a
hydrostatic gradient in transpulmonary pressure. The force that was
required to balance the buoyancy was applied through a clip attached to the
tip of the lobe. The locations of metal markers implanted in the parenchyma
and attached to the surface were tracked, and regional volume and the
horizontal and vertical components of strain were obtained as functions of
vertical position. An engineering analysis of the deformation is
qualitatively consistent with the data, but the predicted strains are
larger than the observed strains. From the experimental and analytical
results, we conclude that, for this deformation, the regional volume-local
transpulmonary pressure curve closely follows the pressure-volume curve
because negative horizontal strains nearly balance the positive vertical
strain caused by the buoyancy force.
