Regional deposition and retention of particles in shallow, inhaled boluses: effect of lung volume

1999 ◽  
Vol 86 (1) ◽  
pp. 168-173 ◽  
Author(s):  
William D. Bennett ◽  
Gerhard Scheuch ◽  
Kirby L. Zeman ◽  
James S. Brown ◽  
Chong Kim ◽  
...  
Keyword(s):  
Lung Volume ◽  
Gamma Camera ◽  
Total Lung Capacity ◽  
Aerosol Delivery ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Inhaled Particles ◽  
R Ratio ◽  
Regional Deposition ◽  
Mass Median

The regional deposition of particles in boluses delivered to shallow lung depths and their subsequent retention in the airways may depend on the lung volume at which the boluses are delivered. To evaluate the effect of end-inspiratory lung volume on aerosol bolus delivery, we had healthy subjects inhale radiolabeled, monodisperse aerosol (99mTc-iron oxide, 3.5-μm mass median aerodynamic diameter) boluses (40 ml) to a volumetric front depth of 70 ml into the lung at lung volumes of 50, 70, and 85% of total lung capacity (TLC) end inhalation. By gamma camera analysis, we found significantly greater deposition in the left (L) vs. right (R) lungs at the 70 and 85% TLC end inhalation; ratio of deposition in L to R lung, normalized to L-to-R ratio of lung volume (mean L/R), was 1.60 ± 0.45 (SD) and 1.96 ± 0.72, respectively ( P < 0.001 for comparison to 1.0) for posterior images. However, at 50% TLC, L/R was 1.23 ± 0.37, not significantly different from 1.0. These data suggest that the L and R lungs may be expanding nonuniformly at higher lung volumes. On the other hand, subsequent retention of deposited particles at 2 and 24 h postdeposition was independent of L/R at the various lung volumes. Thus asymmetric bolus ventilation for these very shallow boluses does not lead to significant increases in peripheral alveolar deposition. These data may prove useful for 1) designing aerosol delivery techniques to target bronchial airways and 2) understanding airway retention of inhaled particles.

Bronchial airway deposition and retention of particles in inhaled boluses: effect of anatomic dead space

1998 ◽  
Vol 85 (2) ◽  
pp. 685-694 ◽  
Author(s):  
William D. Bennett ◽  
Gerhard Scheuch ◽  
Kirby L. Zeman ◽  
James S. Brown ◽  
Chong Kim ◽  
...  
Keyword(s):  
Lung Volume ◽  
Dead Space ◽  
Gamma Camera ◽  
Total Lung Capacity ◽  
Relative Volume ◽  
Lung Capacity ◽  
Single Breath ◽  
Inhaled Particles ◽  
Insoluble Particles ◽  
R Ratio

The fractional deposition of particles in boluses delivered to shallow lung depths and their subsequent retention in the airways may depend on the relative volume and size of an individual’s airways. To evaluate the effect of variable anatomic dead space (ADS) on aerosol bolus delivery we had healthy subjects inhale radiolabeled, monodisperse aerosol (99mTc-iron oxide, 3.5 μm mean mondispersed aerosol diameter) boluses (40 ml) to a volumetric front depth of 70 ml into the lung at a lung volume of 70% total lung capacity end inhalation. By using filter techniques, aerosol photometry, and gamma camera analysis, we estimated the fraction of the inhaled boluses deposited in intrathoracic airways (IDF). ADS by single-breath N2 washout was also measured from 70% total lung capacity. Results showed that among all subjects IDF was variable (range = 0.04–0.43, coefficient of variation = 0.54) and increased with decreasing ADS ( r = −0.76, P = 0.001, n = 16). We found significantly greater deposition in the left (L) vs. right (R) lungs; mean L/R (ratio of deposition in L lung to R lung, normalized to ratio of L-to-R lung volume) was 1.58 ± 0.42 (SD; P < 0.001 for comparison with 1.0). Retention of deposited particles at 2 h was independent of ADS or IDF. There was significant retention of particles at 24 h postdeposition (0.27 ± 0.05) and slow clearance of these particles continued through 48 h postdeposition. Finally, analysis of central-to-peripheral ratios of initial deposition and 24-h-retention gamma-camera images suggest significant retention of insoluble particles in large bronchial airways at 24 h postdeposition (i.e., 24 h central-to-peripheral ratio = 1.40 ± 0.44 and 1.82 ± 0.54 in the R and L lung, respectively; P < 0.02 for comparison with 1.0). These data may prove useful for 1) designing aerosol delivery techniques to target bronchial airways and 2) understanding airway retention of inhaled particles.

Effect of Lung Volume on Voice Onset Time (VOT)

1993 ◽  
Vol 36 (3) ◽  
pp. 516-520 ◽  
Author(s):  
Jeannette D. Hoit ◽  
Nancy Pearl Solomon ◽  
Thomas J. Hixon
Keyword(s):  
Lung Volume ◽  
Total Lung Capacity ◽  
Voice Onset Time ◽  
Onset Time ◽  
Speech Disorders ◽  
Residual Volume ◽  
Healthy Individuals ◽  
Lung Volumes ◽  
Lung Capacity

This investigation was designed to test the hypothesis that voice onset time (VOT) varies as a function of lung volume. Recordings were made of five men as they repeated a phrase containing stressed /pi/ syllables, beginning at total lung capacity and ending at residual volume. VOT was found to be longer at high lung volumes and shorter at low lung volumes in most cases. This finding points out the need to take lung volume into account when using VOT as an index of laryngeal behavior in both healthy individuals and those with speech disorders.

Lung volumes and expiratory flow limitation during exercise in interstitial lung disease

1994 ◽  
Vol 77 (2) ◽  
pp. 963-973 ◽  
Author(s):  
D. D. Marciniuk ◽  
G. Sridhar ◽  
R. E. Clemens ◽  
T. A. Zintel ◽  
C. G. Gallagher
Keyword(s):  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Lung Volume ◽  
Total Lung Capacity ◽  
Flow Limitation ◽  
Expiratory Flow Limitation ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Ventilatory Capacity ◽  
Expiratory Flow

Lung volumes were measured at rest and during exercise by an open-circuit N2-washout technique in patients with interstitial lung disease (ILD). Exercise tidal flow-volume (F-V) curves were also compared with maximal F-V curves to investigate whether these patients demonstrated flow limitation. Seven patients underwent 4 min of constant work rate bicycle ergometer exercise at 40, 70, and 90% of their previously determined maximal work rates. End-expiratory lung volume and total lung capacity were measured at rest and near the end of each period of exercise. There was no significant change in end-expiratory lung volume or total lung capacity when resting measurements were compared with measurements at 40, 70, and 90% work rates. During exercise, expiratory flow limitation was evident in four patients who reported stopping exercise because of dyspnea. In the remaining patients who discontinued exercise because of leg fatigue, no flow limitation was evident. In all patients, the mean ratio of maximal minute ventilation to maximal ventilatory capacity (calculated from maximal F-V curves) was 67%. We conclude that lung volumes during exercise do not significantly differ from those at rest in this population and that patients with ILD may demonstrate expiratory flow limitation during exercise. Furthermore, because most patients with ILD are not breathing near their maximal ventilatory capacity at the end of exercise, we suggest that respiratory mechanics are not the primary cause of their exercise limitation.

scholarly journals Influence of lung volume on pulmonary microvascular pressure-volume characteristics

2000 ◽  
Vol 89 (4) ◽  
pp. 1591-1600 ◽  
Author(s):  
George P. Topulos ◽  
Richard E. Brown ◽  
James P. Butler
Keyword(s):  
Lung Volume ◽  
Total Lung Capacity ◽  
Lung Volumes ◽  
Vascular Volume ◽  
Lung Capacity ◽  
Transit Times ◽  
Wide Range ◽  
Residual Capacity ◽  
Volume Characteristics ◽  
Lung Microcirculation

The pressure-volume (P-V) characteristics of the lung microcirculation are important determinants of the pattern of pulmonary perfusion and of red and white cell transit times. Using diffuse light scattering, we measured capillary P-V loops in seven excised perfused dog lobes at four lung volumes, from functional residual capacity (FRC) to total lung capacity (TLC), over a wide range of vascular transmural pressures (Ptm). At Ptm 5 cmH2O, specific compliance of the microvasculature was 8.6%/cmH2O near FRC, decreasing to 2.7%/cmH2O as lung volume increased to TLC. At low lung volumes, the vasculature showed signs of strain stiffening (specific compliance fell as Ptm rose), but stiffening decreased as lung volume increased and was essentially absent at TLC. The P-V loops were smooth without sharp transitions, consistent with vascular distension as the primary mode of changes in vascular volume with changes in Ptm. Hysteresis was small (0.013) at all lung volumes, suggesting that, although surface tension may set basal capillary shape, it does not strongly affect capillary compliance.

scholarly journals Diaphragm thickening during inspiration

1997 ◽  
Vol 83 (1) ◽  
pp. 291-296 ◽  
Author(s):  
David Cohn ◽  
Joshua O. Benditt ◽  
Scott Eveloff ◽  
F. Dennis McCool
Keyword(s):  
Lung Volume ◽  
Vital Capacity ◽  
Total Lung Capacity ◽  
Diaphragm Thickness ◽  
Lung Volumes ◽  
One Dimensional ◽  
Lung Capacity ◽  
The Mean ◽  
Definition Of ◽  
The Relationship

Cohn, David, Joshua O. Benditt, Scott Eveloff, and F. Dennis McCool. Diaphragm thickening during inspiration. J. Appl. Physiol. 83(1): 291–296, 1997.—Ultrasound has been used to measure diaphragm thickness ( T di) in the area where the diaphragm abuts the rib cage (zone of apposition). However, the degree of diaphragm thickening during inspiration reported as obtained by one-dimensional M-mode ultrasound was greater than that predicted by using other radiographic techniques. Because two-dimensional (2-D) ultrasound provides greater anatomic definition of the diaphragm and neighboring structures, we used this technique to reevaluate the relationship between lung volume and T di. We first established the accuracy and reproducibility of 2-D ultrasound by measuring T diwith a 7.5-MHz transducer in 26 cadavers. We found that T di measured by ultrasound correlated significantly with that measured by ruler ( R 2 = 0.89), with the slope of this relationship approximating a line of identity ( y = 0.89 x + 0.04 mm). The relationship between lung volume and T di was then studied in nine subjects by obtaining diaphragm images at the five target lung volumes [25% increments from residual volume (RV) to total lung capacity (TLC)]. Plots of T di vs. lung volume demonstrated that the diaphragm thickened as lung volume increased, with a more rapid rate of thickening at the higher lung volumes [ T di = 1.74 vital capacity (VC)2 + 0.26 VC + 2.7 mm] ( R 2= 0.99; P < 0.001) where lung volume is expressed as a fraction of VC. The mean increase in T di between RV and TLC for the group was 54% (range 42–78%). We conclude that 2-D ultrasound can accurately measure T di and that the average thickening of the diaphragm when a subject is inhaling from RV to TLC using this technique is in the range of what would be predicted from a 35% shortening of the diaphragm.

Static Lung Volumes in Singers

1973 ◽  
Vol 82 (1) ◽  
pp. 89-95 ◽  
Author(s):  
Wilbur J. Gould ◽  
Hiroshi Okamura
Keyword(s):  
Lung Volume ◽  
Total Lung Capacity ◽  
The Other ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Vocal Training ◽  
Professional Singers ◽  
Professional Singer ◽  
Singing Ability

It has long been assumed that the superior vocal ability of the trained professional singer arose from a higher than average breathing capacity and consequent above-normal ventilatory efficiency. However, until now, it has not been clear whether this presumed superior pulmonary capacity and breathing efficiency arose from training, from heredity, or from other factors. To clarify the role of training (and by inference that of other factors also) upon the capacity for singing, various indices reflecting static lung volumes, as distinguished from dynamic parameters measured during the act of singing, in trained professional singers, students of voice and subjects with no vocal training, were compared. Results indicated that contrary to reports by others, there were no significant differences in the total lung capacity (TLC) of the trained professional singer and that of the other two groups when allowances were made for age and sex; but when the ability to mobilize or utilize TLC was compared, it was found that the trained singer was much better able to do this than either of the other two groups. Specifically, it was found that the ratio of the residual lung volume (RV) (the amount of air remaining in the lungs at the end of a total voluntary expiration) to TLC was lower in the trained singer than in the students of voice, and that these students, in turn, had a lower RV/TLC ratio than the untrained subjects. These findings, therefore, suggest that the increased singing ability of the trained professional singer arises in large part from the ability to increase breathing efficiency by reducing the residual lung volume and, further, that this ability tends to improve with length of vocal training.

Hysteresis in the relation between diffusing capacity of the lung and lung volume

1980 ◽  
Vol 49 (4) ◽  
pp. 566-570 ◽  
Author(s):  
S. S. Cassidy ◽  
M. Ramanathan ◽  
G. L. Rose ◽  
R. L. Johnson
Keyword(s):  
Carbon Monoxide ◽  
Functional Residual Capacity ◽  
Lung Volume ◽  
Total Lung Capacity ◽  
Breath Holding ◽  
Residual Volume ◽  
Diffusing Capacity ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Residual Capacity

The diffusing capacity of the lung for carbon monoxide (DLCO) varies directly with lung volume (VA) when measured during a breath-holding interval. DLCO measured during a slow exhalation from total lung capacity (TLC) to functional residual capacity (FRC) does not vary as VA changes. Since VA is reached by inhaling during breath holding and by exhaling during the slow exhalation maneuver, we hypothesized that the variability in the relation between DLCO and VA was due to hysteresis. To test this hypothesis, breath-holding measurements of DLCO were made at three lung volumes, both when VA was reached by inhaling from residual volume (RV) and when Va was reached by exhaling from TLC. At 72% TLC, DLCO was 22% higher when VA was reached by exhalation compared to inhalation (P < 0.02). At 52% TLC, DLCO was 19% higher when VA was reached by exhalation compared to exhalation (P < 0.005). DCLO measured during a slow exhalation fell on the exhalation limb of the CLCO/VA curve. these data indicate that there is hysteresis in DLCO with respect to lung volume.

scholarly journals Quantification of gas exchange-related upward motion of the liver during prolonged breathholding—potential reduction of motion artifacts in abdominal MRI

2020 ◽  
Vol 93 (1106) ◽  
pp. 20190549 ◽  
Author(s):  
Rachita Khot ◽  
Melissa McGettigan ◽  
James T Patrie ◽  
Sebastian Feuerlein
Keyword(s):  
Lung Volume ◽  
Total Lung Capacity ◽  
Motion Artifacts ◽  
Breath Holding ◽  
Upward Motion ◽  
Liver Mri ◽  
Lung Volumes ◽  
Total Lung Volume ◽  
Lung Capacity ◽  
Upward Shift

Objective: To test the hypothesis that there is a measureable upward motion of the diaphragm during prolonged breath-holds that could have a detrimental effect on image quality in liver MRI and to identify factor that potentially influence the magnitude of this motion. Methods: 15 healthy volunteers underwent MRI examination using prolonged breath-holds in the maximum inspiratory position and a moderate inspiratory position. Coronal T1 weighted three-dimensional gradient echo sequences of the entire thorax were acquired every 6 s during breath-holding allowing the calculation of total lung volume and the measurement of the absolute position of the dome of the liver. The potential impact of subject’s gender, body mass index, and total lung capacity on the change in lung volume/diaphragmatic motion was assessed using random coefficient regression. Results: All volunteers demonstrated a slow reduction of the total lung volume during prolonged breath-holding up to 123 ml. There was a measurable associated upward shift of the diaphragm, measuring up to 5.6 mm after 24 s. There was a positive correlation with female gender (p = 0.037) and total lung volume (p = 0.005) and a negative association with BMI (p = 0.012) for the maximum inspiratory position only. Conclusion: There is a measureable reduction of lung volumes with consecutive upward shift of the diaphragm during prolonged breath-holding which likely contributes to motion artifacts in liver MRI. Advances in knowledge: There is a measureable gas exchange-related reduction of lung volumes with consecutive upward shift of the diaphragm during prolonged breath-holding which likely contributes to motion artifacts in liver MRI. Correcting for this predictable upward shift has potential to improve image quality. The magnitude of this effect does not seem to be related to gender, BMI or total lung capacity if a moderate inspiratory position is used.

Lung volumes of singers

1960 ◽  
Vol 15 (1) ◽  
pp. 40-42 ◽  
Author(s):  
Stanley S. Heller ◽  
William R. Hicks ◽  
Walter S. Root
Keyword(s):  
Lung Volume ◽  
Vital Capacity ◽  
Total Lung Capacity ◽  
Residual Volume ◽  
Inspiratory Capacity ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Vocal Training ◽  
Professional Singers ◽  
Residual Capacity

Lung volume determinations (tidal volume, inspiratory capacity, inspiratory reserve volume, expiratory reserve volume, vital capacity, maximum breathing capacity, functional residual capacity, residual volume, and total lung capacity) were carried out on 16 professional singers and 21 subjects who had had no professional vocal training. No differences were found between the two groups of subjects, whether recumbent or standing, which could not be explained upon the basis of age, size, or errors involved in making the measurements. Submitted on March 24, 1959

Lung volume and effectiveness of inspiratory muscles

1993 ◽  
Vol 74 (2) ◽  
pp. 688-694 ◽  
Author(s):  
A. Brancatisano ◽  
L. A. Engel ◽  
S. H. Loring
Keyword(s):  
Lung Volume ◽  
Muscle Activity ◽  
Vital Capacity ◽  
Total Lung Capacity ◽  
Normal Subjects ◽  
Lung Volumes ◽  
Mechanical Advantage ◽  
Lung Capacity ◽  
Inspiratory Muscles ◽  
Volume Dependence

We related inspiratory muscle activity to inspiratory pressure generation (Pmus) at different lung volumes in five seated normal subjects. Integrated electromyograms were recorded from diaphragmatic crura (Edi), parasternals (PS), and lateral external intercostals (EI). At 20% increments in the vital capacity (VC) subjects relaxed and then made graded and maximal inspiratory efforts against an occluded airway. At any given level of pressure generation, Edi, PS, and EI increased with increasing lung volume. The Pmus generated at total lung capacity as a fraction of that at a low lung volume (between residual volume and 40% VC) was 0.39 +/- 0.15 (SD) for the diaphragm, 0.20 +/- 0.06 for PS, and 0.22 +/- 0.04 for the lateral EI muscles. Our results indicate a lesser volume dependence of the Pmus-EMG relationship for the diaphragm than for PS and EI muscles. This difference in muscle effectiveness with lung volume may reflect differences in length-tension and/or geometric mechanical advantage between the rib cage muscles and the diaphragm.

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