Journal of Applied Physiology, Vol 76, Issue 5 2106-2113, Copyright © 1994 by American Physiological Society
Application of an air-filled tube for measuring intraesophageal pressure
K. Shiraishi, M. Yaekashiwa, J. Nakagawa, T. Isawa and M. Motomiya
Department of Medicine, Tohoku University, Sendai, Japan.
We devised a new method for measuring esophageal pressure (Pes) with use of
a flexible tube without a balloon at a constant rate of airflow through the
tube into the esophagus (balloonless method). A study with 133Xe showed
that the air that accumulated in the esophagus did not interfere with the
measurement of Pes. We measured dynamic compliance (Cdyn) and pulmonary
resistance (RL) with the balloonless method in 19 subjects and obtained a
static deflation pressure-volume curve (P-V curve) in 10 other subjects.
Cdyn was 0.243 +/- 0.099 l/cmH2O and RL was 1.52 +/- 0.42 cmH2O.l-1.s. In 6
of the 10 subjects, a P-V curve was also obtained with the balloon tube
(balloon method). K, the index of compliance in the exponential function V
= V0(1-e-KP) where V0 is volume at infinite pressure, was 0.136 +/- 0.040
cmH2O-1 with the balloonless method and 0.153 +/- 0.023 cmH2O-1 with the
balloon method. No statistically significant difference was found between
these two values. In conclusion, Cdyn, RL, and the P-V curve can be
obtained precisely with the balloonless method.
