scholarly journals Effects of rapid saline infusion on lung mechanics and airway responsiveness in humans

2003 ◽  
Vol 95 (2) ◽  
pp. 728-734 ◽  
Author(s):  
Riccardo Pellegrino ◽  
Raffaele Dellacà ◽  
Peter T. Macklem ◽  
Andrea Aliverti ◽  
Stefania Bertini ◽  
...  
Keyword(s):  
Functional Residual Capacity ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Airway Responsiveness ◽  
Saline Infusion ◽  
Lung Mechanics ◽  
Elastic Recoil ◽  
Lung Volumes ◽  
Residual Capacity

Lung mechanics and airway responsiveness to methacholine (MCh) were studied in seven volunteers before and after a 20-min intravenous infusion of saline. Data were compared with those of a time point-matched control study. The following parameters were measured: 1-s forced expiratory volume, forced vital capacity, flows at 40% of control forced vital capacity on maximal (V̇m40) and partial (V̇p40) forced expiratory maneuvers, lung volumes, lung elastic recoil, lung resistance (Rl), dynamic elastance (Edyn), and within-breath resistance of respiratory system (Rrs). Rl and Edyn were measured during tidal breathing before and for 2 min after a deep inhalation and also at different lung volumes above and below functional residual capacity. Rrs was measured at functional residual capacity and at total lung capacity. Before MCh, saline infusion caused significant decrements of forced expiratory volume in 1 s, V̇m40, and V̇p40, but insignificantly affected lung volumes, elastic recoil, Rl, Edyn, and Rrs at any lung volume. Furthermore, saline infusion was associated with an increased response to MCh, which was not associated with significant changes in the ratio of V̇m40 to V̇p40. In conclusion, mild airflow obstruction and enhanced airway responsiveness were observed after saline, but this was not apparently due to altered elastic properties of the lung or inability of the airways to dilate with deep inhalation. It is speculated that it was likely the result of airway wall edema encroaching on the bronchial lumen.

Deep breaths, methacholine, and airway narrowing in healthy and mild asthmatic subjects

2002 ◽  
Vol 93 (4) ◽  
pp. 1384-1390 ◽  
Author(s):  
Emanuele Crimi ◽  
Riccardo Pellegrino ◽  
Manlio Milanese ◽  
Vito Brusasco
Keyword(s):  
Forced Vital Capacity ◽  
Healthy Subjects ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Forced Expiration ◽  
Airway Narrowing ◽  
Significant Difference ◽  
Mild Asthmatic ◽  
Residual Capacity ◽  
Airway Conductance

Deep breaths taken before inhalation of methacholine attenuate the decrease in forced expiratory volume in 1 s and forced vital capacity in healthy but not in asthmatic subjects. We investigated whether this difference also exists by using measurements not preceded by full inflation, i.e., airway conductance, functional residual capacity, as well as flow and residual volume from partial forced expiration. We found that five deep breaths preceding a single dose of methacholine 1) transiently attenuated the decrements in forced expiratory volume in 1 s and forced vital capacity in healthy ( n = 8) but not in mild asthmatic ( n = 10) subjects and 2) increased the areas under the curve of changes in parameters not preceded by a full inflation over 40 min, during which further deep breaths were prohibited, without significant difference between healthy ( n = 6) and mild asthmatic ( n = 16) subjects. In conclusion, a series of deep breaths preceding methacholine inhalation significantly enhances bronchoconstrictor response similarly in mild asthmatic and healthy subjects but facilitates bronchodilatation on further full inflation in the latter.

A comparison of lung volumes between divers and submariners in the Royal Navy

1984 ◽  
Vol 70 (3) ◽  
pp. 143-148
Author(s):  
G. M. Clifford ◽  
D. J. Smith ◽  
Cardine S. M. Searing
Keyword(s):  
Linear Regression ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Royal Navy ◽  
Predictive Equations ◽  
Lung Volumes ◽  
Job Classification ◽  
Single Breath ◽  
Expected Values

SummaryA comparison of spirometric values in divers and submariners of the Royal Navy and their physical characteristics was undertaken. Four hundred and twenty-two subjects were included in the study, of whom 192 were divers and 230 submariners. Measurements of forced vital capacity (FYC), forced expiratory volume in one second (FEY1) and FEY1/FYC ratio were made using a single breath wedge spirometer (YitalographR). The data was analysed by multiple linear regression and analysis of variance. FYC and FEY1 increased with height and decreased with age though inclusion of a quadratic age term showed that the decline with age did not begin until the mid-thirties, casting doubt on the validity of predictive equations which assume a linear decrease from age 25. The divers had significantly larger lung volumes than the submariners though in the former this did not correlate with either experience or job classification. The FEY1/FYC ratio declined with age in both groups. It was also shown that those individuals with a large FYC tend to have a relatively lower FEY1/FYC ratio than those with small FYCs. Predictive equations for both divers and submariners were calculated which are more appropriate for determining expected values for the two groups than hose currently in use.

Inflation of antishock trousers increases bronchial response to methacholine in healthy subjects

1990 ◽  
Vol 68 (4) ◽  
pp. 1528-1533 ◽  
Author(s):  
J. Regnard ◽  
P. Baudrillard ◽  
B. Salah ◽  
A. T. Dinh Xuan ◽  
L. Cabanes ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Vital Capacity ◽  
Alternative Explanation ◽  
Venous Occlusion ◽  
Forced Expiratory Volume ◽  
Lower Limbs ◽  
Base Line ◽  
Lung Volumes ◽  
Residual Capacity ◽  
Lung Vessels

We studied changes in lung volumes and in bronchial response to methacholine chloride (MC) challenge when antishock trousers (AST) were inflated at venous occlusion pressure in healthy subjects in the standing posture, a maneuver known to shift blood toward lung vessels. On inflation of bladders isolated to lower limbs, lung volumes did not change but bronchial response to MC increased, as evidenced by a greater fall in the forced expiratory volume in 1 s (FEV1) at the highest dose of MC used compared with control without AST inflation (delta FEV1 = 0.94 +/- 0.40 vs. 0.66 +/- 0.46 liter, P less than 0.001). Full inflation of AST, i.e., lower limb and abdominal bladder inflated, significantly reduced vital capacity (P less than 0.001), functional residual capacity (P less than 0.01), and FEV1 (P less than 0.01) and enhanced the bronchial response to MC challenge compared with partial AST inflation (delta FEV1 = 1.28 +/- 0.47 liter, P less than 0.05). Because there was no significant reduction of lung volumes on partial AST inflation, the enhanced bronchial response to MC cannot be explained solely by changes in base-line lung volumes. An alternative explanation might be a congestion and/or edema of the airway wall on AST inflation. Therefore, to investigate further the mechanism of the increased bronchial response to MC, we pretreated the subjects with the inhaled alpha 1-adrenergic agonist methoxamine, which has both direct bronchoconstrictor and bronchial vasoconstrictor effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Mechanical properties of the lungs during acclimatization to altitude

1982 ◽  
Vol 52 (6) ◽  
pp. 1407-1415 ◽  
Author(s):  
H. Gautier ◽  
R. Peslin ◽  
A. Grassino ◽  
J. Milic-Emili ◽  
B. Hannhart ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Forced Expiratory Volume ◽  
Lung Mechanics ◽  
Elastic Recoil ◽  
Lung Capacity ◽  
Pulmonary Flow ◽  
The Face ◽  
Residual Capacity ◽  
Mouth Occlusion Pressure ◽  
Flow Resistances

Mechanical properties of the lung were studied in nine healthy lowlanders during a 6-day sojourn at an altitude of 3,457 m. In comparison to sea-level values, it was found at altitude that 1) lung volumes measured by plethysmography including total lung capacity, vital capacity, and functional residual capacity (FRC) presented small changes not exceeding 300 ml; 2) static and dynamic lung compliances were not modified but static pressure-volume curves of lungs were shifted progressively to the left (the decrease in lung elastic recoil averaged about 2 cmH2O on days 4–6); and 3) maximal midexpiratory flow, forced expiratory volume in 1 s, and maximal expiratory and inspiratory flows were increased and, conversely, airways and pulmonary flow resistances were decreased on most days at altitude. The unchanged FRC in the face of a decreased lung recoil may be explained by an increase in thoracic blood volume at altitude, but other possible mechanisms are discussed. The decrease in resistances and increase in maximal flows may be partly explained by the decreased air density at altitude, but another contributing factor such as a bronchodilatation is also suggested. It is proposed that changes in lung mechanics at altitude may account for some of the changes in the pattern of breathing and mouth occlusion pressure (P0.1) observed during acclimatization of lowlanders to altitude.

scholarly journals Influence of heart failure on resting lung volumes in patients with COPD

2016 ◽  
Vol 42 (4) ◽  
pp. 273-278 ◽  
Author(s):  
Aline Soares de Souza ◽  
Priscila Abreu Sperandio ◽  
Adriana Mazzuco ◽  
Maria Clara Alencar ◽  
Flávio Ferlin Arbex ◽  
...  
Keyword(s):  
Heart Failure ◽  
Vital Capacity ◽  
Whole Body ◽  
Elastic Recoil ◽  
Inspiratory Capacity ◽  
Lung Volumes ◽  
Residual Capacity ◽  
Clinical Stabilization ◽  
A Prospective Study ◽  
Whole Body Plethysmography

ABSTRACT Objective: To evaluate the influence of chronic heart failure (CHF) on resting lung volumes in patients with COPD, i.e., inspiratory fraction-inspiratory capacity (IC)/TLC-and relative inspiratory reserve-[1 − (end-inspiratory lung volume/TLC)]. Methods: This was a prospective study involving 56 patients with COPD-24 (23 males/1 female) with COPD+CHF and 32 (28 males/4 females) with COPD only-who, after careful clinical stabilization, underwent spirometry (with forced and slow maneuvers) and whole-body plethysmography. Results: Although FEV1, as well as the FEV1/FVC and FEV1/slow vital capacity ratios, were higher in the COPD+CHF group than in the COPD group, all major "static" volumes-RV, functional residual capacity (FRC), and TLC-were lower in the former group (p < 0.05). There was a greater reduction in FRC than in RV, resulting in the expiratory reserve volume being lower in the COPD+CHF group than in the COPD group. There were relatively proportional reductions in FRC and TLC in the two groups; therefore, IC was also comparable. Consequently, the inspiratory fraction was higher in the COPD+CHF group than in the COPD group (0.42 ± 0.10 vs. 0.36 ± 0.10; p < 0.05). Although the tidal volume/IC ratio was higher in the COPD+CHF group, the relative inspiratory reserve was remarkably similar between the two groups (0.35 ± 0.09 vs. 0.44 ± 0.14; p < 0.05). Conclusions: Despite the restrictive effects of CHF, patients with COPD+CHF have relatively higher inspiratory limits (a greater inspiratory fraction). However, those patients use only a part of those limits, probably in order to avoid critical reductions in inspiratory reserve and increases in elastic recoil.

Effect of breathing helium-oxygen on static lung volumes and lung recoil in normal man

1977 ◽  
Vol 42 (6) ◽  
pp. 899-902 ◽  
Author(s):  
M. A. Hutcheon ◽  
J. R. Rodarte ◽  
R. E. Hyatt
Keyword(s):  
Clinical Utility ◽  
Vital Capacity ◽  
Total Lung Capacity ◽  
Normal Subjects ◽  
T Test ◽  
Elastic Recoil ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Residual Capacity ◽  
Normal Man

Static lung volumes and static elastic recoil pressure (Pel) were measured in normal subjects breathing air and 80% helium plus 20% oxygen (He+O2). In 22 subjects, He+O2 produced small but significant increases in total lung capacity (TLC) (mean 0.11 liter, P less than 0.001) and residual volume (mean 0.10 liter, P less than 0.01) without change in vital capacity or functional residual capacity. The mechanisms for this change are obscure. In 10 subjects, breathing He+O2 had no significant effect on Pel (paired t-test) at any lung volume measured (50–80% TLC). In one subject, Pel at 70 and 80% TLC was significantly higher on air than on He+O2 (unpaired t-test, P less than 0.05). Because changes in lung volumes and lung recoil were small, we concluded that these effects do not negate the clinical utility of He+O2 flow-volume curves.

Forced expirations and maximum expiratory flow-volume curves during sustained microgravity on SLS-1

1996 ◽  
Vol 81 (1) ◽  
pp. 33-43 ◽  
Author(s):  
A. R. Elliott ◽  
G. K. Prisk ◽  
H. J. Guy ◽  
J. M. Kosonen ◽  
J. B. West
Keyword(s):  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Slight Reduction ◽  
Flow Volume ◽  
Lung Volumes ◽  
Volume Curve ◽  
Supine Posture ◽  
Maximum Expiratory Flow ◽  
Expiratory Flow

Gravity is known to influence the mechanical behavior of the lung and chest wall. However, the effect of sustained microgravity (microG) on forced expirations has not previously been reported. Tests were carried out by four subjects in both the standing and supine postures during each of seven preflight and four postflight data-collection sessions and four times during the 9 days of microG exposure on Spacelab Life Sciences-1. Compared with preflight standing values, peak expiratory flow rate (PEFR) was significantly reduced by 12.5% on flight day 2 (FD2), 11.6% on FD4, and 5.0% on FD5 but returned to standing values by FD9. The supine posture caused a 9% reduction in PEFR. Forced vital capacity and forced expired volume in 1 s were slightly reduced (approximately 3-4%) on FD2 but returned to preflight standing values on FD4 and FD5, and by FD9 both values were slightly but significantly greater than standing values. Forced vital capacity and forced expiratory volume in 1 s were both reduced in the supine posture (approximately 8-10%). Forced expiratory flows at 50% and between 25 and 75% of vital capacity did not change during microG but were reduced in the supine posture. Analysis of the maximum expiratory flow-volume curve showed that microG caused no consistent change in the curve configuration when individual in-flight days were compared with preflight standing curves, although two subjects did show a slight reduction in flows at low lung volumes from FD2 to FD9. The interpretation of the lack of change in curve configuration must be made cautiously because the lung volumes varied from day to day in flight. Therefore, the flows at absolute lung volumes in microG and preflight standing are not being compared. The supine curves showed a subtle but consistent reduction in flows at low lung volumes. The mechanism responsible for the reduction in PEFR is not clear. It could be due to a lack of physical stabilization when performing the maneuver in the absence of gravity or a transient reduction in respiratory muscle strength.

scholarly journals Exercise-induced bronchodilation in natural and induced asthma: effects on ventilatory response and performance

2002 ◽  
Vol 92 (6) ◽  
pp. 2353-2360 ◽  
Author(s):  
Emanuele Crimi ◽  
Riccardo Pellegrino ◽  
Attilio Smeraldi ◽  
Vito Brusasco
Keyword(s):  
Tidal Volume ◽  
Functional Residual Capacity ◽  
Lung Volume ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Breathing Frequency ◽  
Forced Expiratory Flow ◽  
Residual Capacity ◽  
Group 2 ◽  
Group 1

We studied whether bronchodilatation occurs with exercise during the late asthmatic reaction (LAR) to allergen ( group 1, n = 13) or natural asthma (NA; group 2, n = 8) and whether this is sufficient to preserve maximum ventilation (V˙e max), oxygen consumption (V˙o 2 max), and exercise performance (W˙max ). In group 1, partial forced expiratory flow at 30% of resting forced vital capacity increased during exercise, both at control and LAR. W˙max was slightly reduced at LAR, whereasV˙e max, tidal volume, breathing frequency, and V˙o 2 max were preserved. Functional residual capacity and end-inspiratory lung volume were significantly larger at LAR than at control. In group 2, partial forced expiratory flow at 30% of resting forced vital capacity increased greatly with exercise during NA but did not attain control values after appropriate therapy. Compared with control, W˙max was slightly less during NA, whereas V˙o 2 maxand V˙e max were similar. Functional residual capacity, but not end-inspiratory lung volume at maximum load, was significantly greater than at control, whereas tidal volume decreased and breathing frequency increased. In conclusion, remarkable exercise bronchodilation occurs during either LAR or NA and allowsV˙e max andV˙o 2 max to be preserved with small changes in breathing pattern and a slight reduction inW˙max.

Dependence of maximal flow-volume curves on time course of preceding inspiration

1993 ◽  
Vol 75 (3) ◽  
pp. 1155-1159 ◽  
Author(s):  
E. D'Angelo ◽  
E. Prandi ◽  
J. Milic-Emili
Keyword(s):  
Time Course ◽  
Vital Capacity ◽  
Normal Subjects ◽  
Forced Expiratory Volume ◽  
Flow Volume ◽  
Maximal Flow ◽  
Lung Volumes ◽  
Residual Capacity ◽  
Expiratory Flow ◽  
Volume Range

Thirteen normal subjects, sitting in a body plethysmograph and breathing through a pneumotachograph, performed forced vital capacity maneuvers after a rapid inspiration without or with an end-inspiratory pause (maneuvers 1 and 2) and after a slow inspiration without or with an end-inspiratory pause (maneuvers 3 and 4), the pause lasting 4–6 s. Inspirations were initiated close to functional residual capacity. At all lung volumes, expiratory flow was larger with maneuver 1 than with any other maneuver and, over the upper volume range, larger with maneuver 3 than with maneuver 4, whereas it was similar for maneuvers 2 and 4. Relative to corresponding values with maneuver 4, peak expiratory flow was approximately 16 and approximately 4% larger with maneuvers 1 and 3, respectively, whereas forced expiratory volume in 1 s increased by approximately 5% only with maneuver 1. The time dependence of maximal flow-volume curves is consistent with the presence of viscoelastic elements within the respiratory system (D'Angelo et al. J. Appl. Physiol. 70: 2602–2610, 1991).

scholarly journals Tidal volume single-breath washin of SF6 and CH4 in transient microgravity

2003 ◽  
Vol 94 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Brigitte Dutrieue ◽  
Manuel Paiva ◽  
Sylvia Verbanck ◽  
Marine Le Gouic ◽  
Chantal Darquenne ◽  
...  
Keyword(s):  
Tidal Volume ◽  
Conformational Changes ◽  
Functional Residual Capacity ◽  
Vital Capacity ◽  
Time Dependent ◽  
Phase Iii ◽  
Lung Volumes ◽  
Single Breath ◽  
Residual Capacity ◽  
Slope Difference

We performed tidal volume single-breath washins (SBW) by using tracers of different diffusivity and varied the time spent in microgravity (μG) before the start of the tests to look for time-dependent effects. SF6 and CH4 phase III slopes decreased by 35 and 26%, respectively, in μG compared with 1 G ( P < 0.05), and the slope difference between gases disappeared. There was no effect of time in μG, suggesting that neither the hypergravity period preceding μG nor the time spent in μG affected gas mixing at volumes near functional residual capacity. In previous studies using SF6 and He (Lauzon A-M, Prisk GK, Elliott AR, Verbanck S, Paiva M, and West JB. J Appl Physiol 82: 859–865, 1997), the vital capacity SBW showed an increase in slope difference between gases in transient μG, the opposite of the decrease in sustained μG. In contrast, tidal volume SBW showed a decrease in slope difference in both μG conditions. Because it is only the behavior of the more diffusive gas that differed between maneuvers and μG conditions, we speculate that, in the previous vital capacity SBW, the hypergravity period preceding the test in transient μG provoked conformational changes at low lung volumes near the acinar entrance.

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