Journal of Applied Physiology, Vol 63, Issue 3 1142-1146, Copyright © 1987 by American Physiological Society
Measurement of pleural pressure at low and high frequencies in normal rabbits
D. A. Chartrand, T. H. Ye, J. M. Maarek and H. K. Chang
Department of Biomedical Engineering, University of Southern California, Los Angeles 90089.
In eight tracheotomized adult rabbits placed in the supine position, we
employed a catheter-tip piezoresistive pressure transducer to measure
esophageal pressure (Pes) and assessed the validity of taking the changes
in Pes to be the changes in pleural pressure (Ppl). We applied an occlusion
test in which the tracheal cannula was occluded during either spontaneous
inspiratory efforts or body surface oscillations ranging from 3 to 50 Hz.
The relationship between Pes and airway opening pressure (Pao) was
recorded. In all instances, the changes in Pes and Pao were virtually
identical in both amplitude and phase. We conclude that, as evaluated by
the occlusion test, a catheter-tip pressure transducer placed in the
esophagus of rabbits can give adequate estimation of local pleural changes
up to at least 50 Hz.
