Effect of chest strapping on regional lung function

1975 ◽  
Vol 39 (5) ◽  
pp. 707-713 ◽  
Author(s):  
G. W. Sybrecht ◽  
L. Garrett ◽  
N. R. Anthonisen
Keyword(s):  
Lung Function ◽  
Regional Distribution ◽  
Lung Mechanics ◽  
Airway Closure ◽  
Elastic Recoil ◽  
Lung Volumes ◽  
Regional Lung Function ◽  
Regional Lung ◽  
Maximum Expiratory Flow ◽  
Expiratory Flow

We studied lung mechanics and regional lung function in five young men during restrictive chest strapping. The effects on lung mechanics were similar to those noted by others in that lung elastic recoil increased as did maximum expiratory flow at low lung volumes. Chest strapping reduced the maximum expiratory flow observed at a given elastic recoil pressure. Breathing helium increased maximum expiratory flow less when subjects were strapped than when they were not. These findings indicated that strapping decreased the caliber of airways upstream from the equal pressure point. Regional lung volumes from apex to base were measured with xenon 133 while subjects were seated. The distribution of regional volumes was measured at RV, and at volumes equal to strapped FRC and strapped TLC; no change due to chest strapping was observed. Similarly, the regional distribution of 133Xe boluses inhaled at RV and strapped TLC was unaffected by chest strapping. Closing capacity decreased with chest strapping. We concluded that airway closure decreased during chest strapping and that airway closure was not the cause of the observed increase in elastic recoil of the lung. The combination of decreased slope of the static pressure-volume curve and unchanged regional volumes suggested that strapping increased the apex-to-base pleural pressure gradient.

Human lung mechanics during water immersion

1976 ◽  
Vol 40 (3) ◽  
pp. 320-323 ◽  
Author(s):  
C. Prefaut ◽  
E. Lupi-h ◽  
N. R. Anthonisen
Keyword(s):  
Human Lung ◽  
Water Immersion ◽  
Maximum Flow ◽  
Lung Mechanics ◽  
Elastic Recoil ◽  
Lung Volumes ◽  
Vascular Congestion ◽  
Maximum Expiratory Flow ◽  
Expiratory Flow ◽  
The Relationship

We measured lung volumes, static deflation pressure-volume curves of the lung, maximum expiratory flow-volume curves, and closing capacities in five men standing immersed to the neck in water. FRC was decreased 27%, while other lung volumes did not change significantly. At high lung volumes immersion tended to increase lung elastic recoil while recoil was decreased at low lung volumes, changes compatible with vascular congestion. Maximum expiratory flow was increased at high lung volumes, probably because of hydrostatic pressure. At low lung volumes maximum expiratory flow was decreased. This was probably due to decreased recoil since the relationship between elastic recoil and maximum flow was unchanged. Closing capacities by the N2 technique were unchanged but the slope of the alveolar plateau and the amplitude of cardiogenic oscillations were decreased in some individuals. Static and dynamic lung properties were unchanged by 5 min of immersion with tidal volume restricted to 0.5 liter. Though immersion produced volume restriction comparable with that reported with chest strapping, it did not produce similar changes in lung mechanics.

Relationship of lung recoil to lung volume and maximum expiratory flow in normal children

1977 ◽  
Vol 42 (6) ◽  
pp. 817-823 ◽  
Author(s):  
A. L. Mansell ◽  
A. C. Bryan ◽  
H. Levison
Keyword(s):  
Elastic Recoil ◽  
Normal Children ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Maximum Expiratory Flow ◽  
Fixed Proportion ◽  
Residual Capacity ◽  
Expiratory Flow ◽  
Infancy And Early Childhood ◽  
Relationship Of

Thirty-one normal children, aged 6--18 yr, were studied by measurements of static lung volumes, static expiratory pressure-volume (PV) curves, and maximum expiratory flow-volume (MEFV) curves. A theoretical standard volume was used to compare children of differing size and this showed that total lung capacity (TLC) is also a valid standard volume. The shape of the PV curve was found to change so that static elastic recoil at a fixed proportion of TLC was higher in older than in younger children. This was also true of static recoil at functional residual capacity (FRC) and an associated increase in the ratio of FRC to TLC was interpreted as evidence for increase in outward recoil of the chest wall during childhood. Since static recoil at “closing capacity” (CC) remained constant, a decrease in the ratio of CC to TLC was quantitatively explained by the PV shift during childhood. Although maximum expiratory flow at various lung volumes increased in constant proportion to TLC, “upstream conductance” decreased relative to TLC. It was concluded that maturation of the respiratory system is disproportionate in several features during childhood and that these disproportions are likely to be even more prominent during infancy and early childhood.

scholarly journals FIRST-IN-HUMAN VALIDATION OF X-RAY VELOCIMETRY DEMONSTRATES SUPERIOR SENSITIVITY OVER SPIROMETRY AND CT FOR QUANTIFICATION OF REGIONAL LUNG FUNCTION

CHEST Journal ◽  
2020 ◽  
Vol 158 (4) ◽  
pp. A1393-A1394
Author(s):  
Jonathan Dusting ◽  
Olivia Stephens ◽  
David Wenger ◽  
Chandni Doshi ◽  
John DeMarco ◽  
...  
Keyword(s):  
Lung Function ◽  
X Ray ◽  
Regional Lung Function ◽  
Regional Lung ◽  
Human Validation

Breathing at low lung volumes and chest strapping: a comparison of lung mechanics

1981 ◽  
Vol 50 (3) ◽  
pp. 650-657 ◽  
Author(s):  
N. J. Douglas ◽  
G. B. Drummond ◽  
M. F. Sudlow
Keyword(s):  
Lung Volume ◽  
Maximum Flow ◽  
Normal Subjects ◽  
Lung Mechanics ◽  
Lung Volumes ◽  
Flow Rates ◽  
Recoil Pressure ◽  
Forced Expiratory Flow ◽  
Expiratory Flow ◽  
Expiratory Flow Rates

In six normal subjects forced expiratory flow rates increased progressively with increasing degrees of chest strapping. In nine normal subjects forced expiratory flow rates increased with the time spent breathing with expiratory reserve volume 0.5 liters above residual volume, the increase being significant by 30 s (P less than 0.01), and flow rates were still increasing at 2 min, the longest time the subjects could breathe at this lung volume. The increase in flow after low lung volume breathing (LLVB) was similar to that produced by strapping. The effect of LLVB was diminished by the inhalation of the atropinelike drug ipratropium. Quasistatic recoil pressures were higher following strapping and LLVB than on partial or maximal expiration, but the rise in recoil pressure was insufficient to account for all the observed increased in maximum flow. We suggest that the effects of chest strapping are due to LLVB and that both cause bronchodilatation.

Effect of aging alone on mechanical properties of the normal adult human lung

1977 ◽  
Vol 43 (6) ◽  
pp. 1054-1062 ◽  
Author(s):  
R. J. Knudson ◽  
D. F. Clark ◽  
T. C. Kennedy ◽  
D. E. Knudson
Keyword(s):  
Respiratory Mechanics ◽  
Human Lung ◽  
Age Groups ◽  
The Elderly ◽  
Elastic Recoil ◽  
Lung Volumes ◽  
Men And Women ◽  
Maximum Expiratory Flow ◽  
Alpha1 Antitrypsin ◽  
Adult Human Lung

For plethysmographic studies of respiratory mechanics, we selected, from a general population, 51 subjects, aged 25–75 yr, who had never smoked, had no present or past cardiorespiratory symptoms or disease, were alpha1-antitrypsin MM phenotypes, and were normal by physical examination, vectorcardiography, and chest roentgenography. Approximately equal numbers of men and women were represented in each of three age groups; 25–35, 36–64, and 65–75. Both sexes demonstrated loss of lung elastic recoil with age, most significant at high lung volumes, but the rate of loss was less than previously reported. Males had higher lung recoil than females of comparable age, but if lung size was taken into account, there were no sex differences in bulk elastic properties. Maximum expiratory flow diminished with age only at low volumes, suggesting that equal pressure points are more centrally located at low lung volumes in the elderly.

Rib cage and abdominal restrictions have different effects on lung mechanics

1980 ◽  
Vol 49 (6) ◽  
pp. 946-952 ◽  
Author(s):  
C. A. Bradley ◽  
N. R. Anthonisen
Keyword(s):  
Lung Volume ◽  
Total Lung Capacity ◽  
Lung Mechanics ◽  
Elastic Recoil ◽  
Rib Cage ◽  
Lung Capacity ◽  
Single Breath ◽  
Restrictive Procedures ◽  
Maximum Expiratory Flow ◽  
Per Se

The effects of a variety of restrictive procedures on lung mechanics were studied in eight healthy subjects. Rib cage restriction decreased total lung capacity (TLC) by 43% and significantly increased elastic recoil and maximum expiratory flow (MEF). Subsequent immersion of four subjects with rib cage restriction resulted in no further change in either parameter; shifts of blood volume did not reverse recoil changes during rib cage restriction. Abdominal restriction decreased TLC by 40% and increased MEF and elastic recoil, but recoil was increased significantly less than was the case with rib cage restriction. Further, at a given recoil pressure, MEF was less during rib cage restriction than during either abdominal restriction or no restriction. Measurements of the unevenness of inspired gas distribution by the single-breath nitrogen technique showed increased unevenness during rib cage restriction, which was significantly greater than that during abdominal restriction. We conclude that lung volume restriction induces changes in lung function, but the nature of these changes depends on how the restriction is applied and therefore cannot be ascribed to low lung volume breathing per se.

Mechanism of reduced maximum expiratory flow in dogs with compensatory lung growth

1986 ◽  
Vol 60 (2) ◽  
pp. 441-448 ◽  
Author(s):  
H. W. Greville ◽  
M. E. Arnup ◽  
S. N. Mink ◽  
L. Oppenheimer ◽  
N. R. Anthonisen
Keyword(s):  
Control Flow ◽  
Sham Operation ◽  
Forced Expiration ◽  
Flow Limitation ◽  
Lung Growth ◽  
Lung Volumes ◽  
Flow Rates ◽  
Compensatory Lung Growth ◽  
Maximum Expiratory Flow ◽  
Expiratory Flow

We examined the mechanism of the reduced maximum expiratory flow rates (Vmax) in a dog model of postpneumonectomy compensatory lung growth. During forced expiration, a Pitot-static tube was used to locate the airway site of flow limitation, or choke point, and to measure dynamic intrabronchial pressures. The factors determining Vmax were calculated and the results analyzed in terms of the wave-speed theory of flow limitation. Measurements were made at multiple lung volumes and during ventilation both with air and with HeO2. Five of the puppies had undergone a left pneumonectomy at 10 wk of age, and 5 littermate controls had undergone a sham operation. All dogs were studied at 26 wk of age, at which time compensatory lung growth had occurred in the postpneumonectomy group. Vmax was markedly decreased in the postpneumonectomy group compared with control, averaging 42% of the control flow rates from 58 to 35% of the vital capacity (VC). At 23% of the VC, Vmax was 15% less than control. Choke points were more peripheral in the postpneumonectomy dogs compared with controls at all volumes. The total airway pressure was the same at the choke-point airway in the postpneumonectomy dogs as that in the same airway in the control dogs, suggesting that the airways of the postpneumonectomy dogs displayed different bronchial area-pressure behavior from the control dogs. Despite the decreased Vmax on both air and HeO2, the density dependence of flow was high in the postpneumonectomy dogs and the same as controls at all lung volumes examined.

scholarly journals Use of Radioactive Xenon for Studies of Regional Lung Function

BMJ ◽  
1962 ◽  
Vol 2 (5311) ◽  
pp. 1006-1016 ◽  
Author(s):  
C. T. Dollery ◽  
P. Hugh-Jones ◽  
C. M. E. Matthews
Keyword(s):  
Lung Function ◽  
Regional Lung Function ◽  
Regional Lung ◽  
Radioactive Xenon
Sign in / Sign up

Export Citation Format

Share Document