Journal of Applied Physiology, Vol 51, Issue 3 678-685, Copyright © 1981 by American Physiological Society
Effect of ventilatory frequency on regional transpulmonary pressure in normal adults
W. Hida, S. Suzuki, H. Sasaki, Y. Fujii, T. Sasaki and T. Takishima
The relation between the ventilatory frequency and the elastic (delta Pel)
or resistive (delta Prs) components of changes of the regional pleural
pressure (delta PL) was studied at functional residual capacity (FRC) in
six normal adults. The regional delta PL was measured simultaneously at
three levels in the esophagus using a three-balloon-catheter system.
Elastic components of regional delta PL normalized by overall tidal volume
(delta Pel/delta V) increased with frequency at all three balloon
positions; the percentages of delta Pel/delta V at 60 breaths/min to those
at zero frequency were 107, 119, and 157% in the upper, middle, and lower
balloon, respectively. The resistive component of regional delta PL
normalized by overall air flow (delta Prs/delta V) did not show significant
dependence on frequency at any of the three positions and was almost the
same everywhere. It is suggested that the increase of local delta Pel with
frequency might reflect mainly the frequency dependence of local dynamic
compliance (Cdyn) and that the change of the local Cdyn with frequency
might be larger in dependent than in upper lung.
