Application of an air-filled tube for measuring intraesophageal pressure

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.

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Measurement of pulmonary resistance and dynamic compliance with airway obstruction

Journal of Applied Physiology ◽

10.1152/jappl.1998.85.5.1982 ◽

1998 ◽

Vol 85 (5) ◽

pp. 1982-1988 ◽

Cited By ~ 33

Author(s):

Todd M. Officer ◽

Riccardo Pellegrino ◽

Vito Brusasco ◽

Joseph R. Rodarte

Keyword(s):

Dynamic Compliance ◽

Normal Subjects ◽

Dynamic Hyperinflation ◽

Least Squares Regression ◽

Pulmonary Resistance ◽

Expiratory Resistance ◽

Volume Curve ◽

Pressure Volume Curve ◽

Before And After ◽

Inspiratory Resistance

We compared four algorithms by using least squares regression for determination of pulmonary resistance and dynamic elastance in subjects with emphysema, normal subjects, and subjects with asthma before and after bronchoconstriction. The four methods evaluated include 1) a single resistance and elastance, 2) separate resistances and elastances for each half breath, 3) separate inspiratory and expiratory resistances with a single elastance, and 4) separate inspiratory and expiratory resistances, an expiratory volume interaction term, and a single elastance. All methods gave comparable results in normal and asthmatic subjects. We found expiratory resistance was larger than inspiratory resistance in normal and asthmatic subjects during control conditions, but inspiratory resistance was higher than expiratory resistance in subjects who experienced severe bronchoconstriction in response to methacholine. In subjects who are flow limited, method 2 gives a higher inspiratory resistance than would be computed by assuming that the elastic pressure-volume curve passes through the zero-flow points. Methods 1 and 3 overestimate dynamic elastance and inspiratory resistance. Method 4appears to identify flow limitation and dynamic hyperinflation and gives a good measure of inspiratory resistance and dynamic elastance.

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Lung volume and pleural pressure in the anesthetized hamster

Journal of Applied Physiology ◽

10.1152/jappl.1979.46.5.927 ◽

1979 ◽

Vol 46 (5) ◽

pp. 927-931 ◽

Cited By ~ 7

Author(s):

Y. L. Lai

Keyword(s):

Lung Volume ◽

Esophageal Pressure ◽

Lung Compliance ◽

Pleural Pressure ◽

Lung Volumes ◽

Lung Capacity ◽

Volume Curve ◽

Pressure Volume Curve ◽

Residual Capacity ◽

Wall Compliance

Lung volumes and respiratory pressures were measured in anesthetized male hamsters weighing an average 117 g. In 16 supine animals functional residual capacity (FRC) determined by body plethysmograph was 1.12 +/- 0.23 (SD) ml (about 20% total lung capacity, TLC) slightly and significantly larger than the FRC measured by saline displacement, 1.01 +/- 0.15 ml. Similar results were found in six prone animals. Paralysis did not significantly alter supine FRC. Contrary to published reports, pleural pressure (Ppl) estimated from esophageal pressure was negative at FRC. The fact that lung volume decreased by 0.2 ml (about 4% TLC) when the chest was opened at FRC provided additional evidence of negative Ppl at FRC. No consistent changes in the lung pressure-volume curve were found after the chest was opened. Deflation chest wall compliance just above FRC was about twice lung compliance. The vital capacity and reserve volumes in this study agreed with values reported in the literature. However, absolute lung volumes (TLC, FRC, and residual volume) were lower by about 1.4 ml, possibly because of earlier overestimates of box FRC.

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Postural variations in pulmonary resistance, dynamic compliance, and esophageal pressure in neonates

Critical Care Medicine ◽

10.1097/00003246-198306000-00005 ◽

1983 ◽

Vol 11 (6) ◽

pp. 424-427 ◽

Cited By ~ 12

Author(s):

ANDRES VANDERGHEM ◽

CAROLINE BEARDSMORE ◽

MICHAEL SILVERMAN

Keyword(s):

Dynamic Compliance ◽

Esophageal Pressure ◽

Pulmonary Resistance

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Use of esophageal balloon pressure-volume curve analysis to determine esophageal wall elastance and calibrate raw esophageal pressure: a bench experiment and clinical study

BMC Anesthesiology ◽

10.1186/s12871-018-0488-6 ◽

2018 ◽

Vol 18 (1) ◽

Cited By ~ 2

Author(s):

Xiu-Mei Sun ◽

Guang-Qiang Chen ◽

Hua-Wei Huang ◽

Xuan He ◽

Yan-Lin Yang ◽

...

Keyword(s):

Clinical Study ◽

Esophageal Pressure ◽

Curve Analysis ◽

Esophageal Wall ◽

Volume Curve ◽

Pressure Volume Curve ◽

Esophageal Balloon ◽

Bench Experiment

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Pressure-volume studies on lung lobes in man

Journal of Applied Physiology ◽

10.1152/jappl.1964.19.4.823 ◽

1964 ◽

Vol 19 (4) ◽

pp. 823-826 ◽

Cited By ~ 1

Author(s):

Koh Ishikawa ◽

C. J. Martin ◽

A. C. Young

Keyword(s):

Mechanical Properties ◽

Vital Capacity ◽

Esophageal Pressure ◽

Chest Cavity ◽

Volume Curve ◽

Pressure Volume Curve ◽

Mean Pressure ◽

Lower Magnitude ◽

Balloon System ◽

Lung Lobes

This study has sought to measure pressure differences occurring within the chest cavity and some of the mechanical properties of lung lobes. One lobe in the hemithorax has been used as an intrapleural pressure capsule by blocking it with a catheter and balloon system. After insertion of an esophageal, a bronchospirometric, and a lobar pressure-measuring catheter, the interrupted vital capacity maneuver has been used to compare pressures within the lungs and esophagus. Pressure differences, which increased as lung volumes increased, were found between lobes, and between lobes and esophagus. Esophageal pressure swings were of lower magnitude than lobar pressure swings. Esophageal pressure was neither linearly related to lobe pressure nor a mean pressure for the hemithorax. Thus, lung volume is not a function of a single pressure within the chest, and the concept of the commonly used pressure-volume curve is oversimplified. mechanical properties; pressure capsules Submitted on October 18, 1963

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Respiratory mechanics of horses measured by conventional and forced oscillation techniques

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.6.2467 ◽

1994 ◽

Vol 76 (6) ◽

pp. 2467-2472 ◽

Cited By ~ 23

Author(s):

S. S. Young ◽

D. Tesarowski

Keyword(s):

Resonant Frequency ◽

Respiratory System ◽

Respiratory Mechanics ◽

Forced Oscillation ◽

Dynamic Compliance ◽

Close Correlation ◽

Esophageal Pressure ◽

Forced Oscillation Technique ◽

Pulmonary Resistance ◽

Oscillation System

Respiratory mechanics were compared using conventional and forced oscillation techniques in six conscious horses and a mechanical model of the equine respiratory system. The parameters calculated from conventional airflow and esophageal pressure measurements were pulmonary resistance and dynamic compliance. The impedance of the respiratory system was measured at 1, 2, and 3 Hz with the forced oscillation technique, and respiratory system resistance, compliance, inertance, and resonant frequency were calculated. Pulmonary resistance was 1.0 +/- 0.3 cmH2O.l-1.s, and pulmonary dynamic compliance was 2.4 +/- 0.6 l/cmH2O. With the use of the forced oscillation system, respiratory resistance was 1.61 +/- 0.50 cmH2O.l-1.s at 1 Hz, compliance was 0.195 +/- 0.075 l/cmH2O, inertance was 0.026 +/- 0.0095 cmH2O.l-1.s2, and resonant frequency was 2.40 +/- 0.25 Hz. Data collected from a model of the respiratory system showed a close correlation between resistance and compliance measured with the two systems. This study demonstrates that the forced oscillation technique is a useful method for noninvasive measurement of respiratory mechanics in horses.

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