scholarly journals Respiratory dynamics during laughter

2001 ◽  
Vol 90 (4) ◽  
pp. 1441-1446 ◽  
Author(s):  
Mario Filippelli ◽  
Riccardo Pellegrino ◽  
Iacopo Iandelli ◽  
Gianni Misuri ◽  
Joseph R. Rodarte ◽  
...  
Keyword(s):  
Chest Wall ◽  
Lung Volume ◽  
Dynamic Compression ◽  
Three Dimensional ◽  
Normal Subjects ◽  
Average Frequency ◽  
Abdominal Pressure ◽  
Sudden Increase ◽  
Lung Volumes ◽  
Transdiaphragmatic Pressure

Lung and chest wall mechanics were studied during fits of laughter in 11 normal subjects. Laughing was naturally induced by showing clips of the funniest scenes from a movie by Roberto Benigni. Chest wall volume was measured by using a three-dimensional optoelectronic plethysmography and was partitioned into upper thorax, lower thorax, and abdominal compartments. Esophageal (Pes) and gastric (Pga) pressures were measured in seven subjects. All fits of laughter were characterized by a sudden occurrence of repetitive expiratory efforts at an average frequency of 4.6 ± 1.1 Hz, which led to a final drop in functional residual capacity (FRC) by 1.55 ± 0.40 liter ( P < 0.001). All compartments similarly contributed to the decrease of lung volumes. The average duration of the fits of laughter was 3.7 ± 2.2 s. Most of the events were associated with sudden increase in Pes well beyond the critical pressure necessary to generate maximum expiratory flow at a given lung volume. Pga increased more than Pes at the end of the expiratory efforts by an average of 27 ± 7 cmH2O. Transdiaphragmatic pressure (Pdi) at FRC and at 10% and 20% control forced vital capacity below FRC was significantly higher than Pdi at the same absolute lung volumes during a relaxed maneuver at rest ( P < 0.001). We conclude that fits of laughter consistently lead to sudden and substantial decrease in lung volume in all respiratory compartments and remarkable dynamic compression of the airways. Further mechanical stress would have applied to all the organs located in the thoracic cavity if the diaphragm had not actively prevented part of the increase in abdominal pressure from being transmitted to the chest wall cavity.

Chest wall and trunk muscle activity during inspiratory loading

1992 ◽  
Vol 73 (6) ◽  
pp. 2373-2381 ◽  
Author(s):  
S. J. Cala ◽  
J. Edyvean ◽  
L. A. Engel
Keyword(s):  
Chest Wall ◽  
Lung Volume ◽  
Normal Subjects ◽  
Systematic Difference ◽  
Erector Spinae ◽  
Inspiratory Pressure ◽  
Emg Activity ◽  
Consistent Difference ◽  
Lung Volumes ◽  
Resistive Loading

We measured the electromyographic (EMG) activity in four chest wall and trunk (CWT) muscles, the erector spinae, latissimus dorsi, pectoralis major, and trapezius, together with the parasternal, in four normal subjects during graded inspiratory efforts against an occlusion in both upright and seated postures. We also measured CWT EMGs in six seated subjects during inspiratory resistive loading at high and low tidal volumes [1,280 +/- 80 (SE) and 920 +/- 60 ml, respectively]. With one exception, CWT EMG increased as a function of inspiratory pressure generated (Pmus) at all lung volumes in both postures, with no systematic difference in recruitment between CWT and parasternal muscles as a function of Pmus. At any given lung volume there was no consistent difference in CWT EMG at a given Pmus between the two postures (P > 0.09). However, at a given Pmus during both graded inspiratory efforts and inspiratory resistive loading, EMGs of all muscles increased with lung volume, with greater volume dependence in the upright posture (P < 0.02). The results suggest that during inspiratory efforts, CWT muscles contribute to the generation of inspiratory pressure. The CWT muscles may act as fixators opposing deflationary forces transmitted to the vertebral column by rib cage articulations, a function that may be less effective at high lung volumes if the direction of the muscular insertions is altered disadvantageously.

Rib cage deformation during static inspiratory efforts

1979 ◽  
Vol 46 (6) ◽  
pp. 1071-1075 ◽  
Author(s):  
N. A. Saunders ◽  
S. M. Kreitzer ◽  
R. H. Ingram
Keyword(s):  
Lung Volume ◽  
Respiratory Muscles ◽  
Normal Subjects ◽  
Esophageal Pressure ◽  
Lung Volumes ◽  
Transdiaphragmatic Pressure ◽  
Rib Cage ◽  
Opposite Change ◽  
Accessory Muscles ◽  
Lateral Diameter

Patterns of rib cage (RC) deformation were studied in six normal subjects during moderate static inspiratory efforts such that esophageal pressure (Pes) as an index of transthoracic pressure fell to between -30 and -60 cmH2O during each maneuver. At lung volumes below 50% inspiratory capacity (IC), static inspiratory efforts deformed RC to a more elliptical shape; RC lateral diameter became smaller and RC lateral diameter became larger. However, at high lung volumes (greater than 50% IC) the opposite change in RC dimensions occurred despite similar changes in Pes, i.e., the RC became more circular. These differences in RC deformation did not appear to be a possive consequence of increased lung volume because the RC could be voluntarily deformed to a more circular shape at low lung volume when a) subjects performed static inspiratory efforts mainly with their intercostal and accessory muscles rather than their diaphragm as judged by a smaller change in transdiaphragmatic pressure for the same Pes; or b) subjects statically contracted their diaphragm with it held in a relatively flattened configuration as assessed by a large abdominal AP dimension. We suggest that deformation of the RC during static inspiratory efforts is not as predictable as has previously been suggested but depends on the pattern of contraction and configuration of the respiratory muscles.

Effects of increased +Gz on chest wall mechanics in humans

1995 ◽  
Vol 78 (3) ◽  
pp. 997-1003 ◽  
Author(s):  
M. Estenne ◽  
A. Van Muylem ◽  
W. Kinnear ◽  
M. Gorini ◽  
V. Ninane ◽  
...  
Keyword(s):  
Chest Wall ◽  
Minute Ventilation ◽  
Normal Subjects ◽  
Abdominal Pressure ◽  
Transdiaphragmatic Pressure ◽  
Parabolic Flights ◽  
Linear Effect ◽  
Chest Wall Mechanics ◽  
Abdominal Compliance ◽  
Tidal Changes

We studied the effects of head-to-foot acceleration (+Gz) on chest wall mechanics in five normal subjects seated in a human centrifuge. Results were compared with those previously obtained in the same subjects in microgravity during parabolic flights. In all subjects, end-expiratory abdominal pressure (Pga) and volume (Vab) increased with Gz. On average, end-expiratory Pga increased from 7.4 +/- 1.7 cmH2O at + 1 Gz to 14.9 +/- 2.8 cmH2O at + 3 Gz and end-expiratory Vab increased by 0.32 +/- 0.06 liter between + 1 and + 3 Gz. On the other hand, the abdominal contribution to tidal volume (Vab/VT) and abdominal compliance decreased from 34.7 +/- 5.9% and 52 +/- 6 ml/cmH2O at + 1 Gz to 29.3 +/- 5.1% and 26 +/- 4 ml/cmH2O at + 3 Gz, respectively. Changes in end-expiratory Pga were linear between 0 and + 3 Gz, but changes in end-expiratory Vab, Vab/VT, and abdominal compliance were greater in microgravity than in hypergravity. In contrast to weightlessness, which did not alter minute ventilation and tidal changes in Pga and transdiaphragmatic pressure, these variables increased with increasing Gz. These results indicate that, although changes in Gz have a linear effect on abdominal transmural pressure, hypergravity and weightlessness do not have symmetrical effects on chest wall mechanics.

Abdominal and thoracic pressures at different lung volumes

1960 ◽  
Vol 15 (6) ◽  
pp. 1087-1092 ◽  
Author(s):  
Emilio Agostoni ◽  
Hermann Rahn
Keyword(s):  
Lung Volume ◽  
Pressure Difference ◽  
Abdominal Pressure ◽  
Alveolar Pressure ◽  
Lung Volumes ◽  
Transdiaphragmatic Pressure ◽  
Similar Difference ◽  
Complete Relaxation

The abdominal (gastric) pressures as well as the intrathoracic pressures were recorded in man during various respiratory maneuvers such as complete relaxation, moderate inspiratory and expiratory efforts, maximal inspiratory and expiratory efforts, and during maximal abdominal pressure efforts. Each maneuver was systematically carried out at various lung volumes. From these measurements it is possible to determine the transdiaphragmatic pressure difference and thus obtain information concerning the activity of the diaphragm during these various maneuvers. During relaxation pressure maneuvers and during moderate expiratory pressure efforts the transdiaphragmatic pressure difference is zero. During maximal inspiratory efforts the pressure is about 100 cm H2O more positive on the abdominal side than on the thoracic side of the diaphragm regardless of the lung volume. A similar difference is found during a maximal abdominal contraction whether during this maneuver the alveolar pressure is zero or whether a high alveolar expiratory pressure is developed. These findings are discussed in terms of reflex contractions of the diaphragm which limit the pressures and volumes that can be obtained in the lung. Submitted on May 2, 1960

scholarly journals Influence of acute lung volume change on contractile properties of human diaphragm

1998 ◽  
Vol 85 (4) ◽  
pp. 1322-1328 ◽  
Author(s):  
Michael I. Polkey ◽  
Carl-Hugo Hamnegård ◽  
Philip D. Hughes ◽  
Gerrard F. Rafferty ◽  
Malcolm Green ◽  
...  
Keyword(s):  
Functional Residual Capacity ◽  
Lung Volume ◽  
Phrenic Nerve ◽  
Stimulus Frequency ◽  
Normal Subjects ◽  
Lung Volumes ◽  
Transdiaphragmatic Pressure ◽  
Residual Capacity ◽  
Interstimulus Intervals

The effect of stimulus frequency on the in vivo pressure generating capacity of the human diaphragm is unknown at lung volumes other than functional residual capacity. The transdiaphragmatic pressure (Pdi) produced by a pair of phrenic nerve stimuli may be viewed as the sum of the Pdi elicited by the first (T1 Pdi) and second (T2 Pdi) stimuli. We used bilateral anterior supramaximal magnetic phrenic nerve stimulation and a digital subtraction technique to obtain the T2 Pdi at interstimulus intervals of 999, 100, 50, 33, and 10 ms in eight normal subjects at lung volumes between residual volume and total lung capacity. The reduction in T2 Pdi that we observed as lung volume increased was greatest at long interstimulus intervals, whereas the T2 Pdi obtained with short interstimulus intervals remained relatively stable over the 50% of vital capacity around functional residual capacity. For all interstimulus intervals, the total pressure produced by the pair decreased as a function of increasing lung volume. These data demonstrate that, in the human diaphragm, hyperinflation has a disproportionately severe effect on the summation of pressure responses elicited by low-frequency stimulations; this effect is distinct from and additional to the known length-tension relationship.

Lung and chest wall mechanics in microgravity

1991 ◽  
Vol 71 (5) ◽  
pp. 1956-1966 ◽  
Author(s):  
J. Edyvean ◽  
M. Estenne ◽  
M. Paiva ◽  
L. A. Engel
Keyword(s):  
Chest Wall ◽  
Dynamic Compliance ◽  
Normal Subjects ◽  
Abdominal Pressure ◽  
Transdiaphragmatic Pressure ◽  
Gastric Pressure ◽  
Abdominal Compliance ◽  
Consistent Change ◽  
Residual Capacity ◽  
Measured Flow

We studied the effect of 15–20 s of weightlessness on lung, chest wall, and abdominal mechanics in five normal subjects inside an aircraft flying repeated parabolic trajectories. We measured flow at the mouth, thoracoabdominal and compartmental volume changes, and gastric pressure (Pga). In two subjects, esophageal pressures were measured as well, allowing for estimates of transdiaphragmatic pressure (Pdi). In all subjects functional residual capacity at 0 Gz decreased by 244 +/- 31 ml as a result of the inward displacement of the abdomen. End-expiratory Pga decreased from 6.8 +/- 0.8 cmH2O at 1 Gz to 2.5 +/- 0.3 cmH2O at Gz (P less than 0.005). Abdominal contribution to tidal volume increased from 0.33 +/- 0.05 to 0.51 +/- 0.04 at 0 Gz (P less than 0.001) but delta Pga showed no consistent change. Hence abdominal compliance increased from 43 +/- 9 to 70 +/- 10 ml/cmH2O (P less than 0.05). There was no consistent effect of Gz on tidal swings of Pdi, on pulmonary resistance and dynamic compliance, or on any of the timing parameters determining the temporal pattern of breathing. The results indicate that at 0 G respiratory mechanics are intermediate between those in the upright and supine postures at 1 G. In addition, analysis of end-expiratory pressures suggests that during weightlessness intra-abdominal pressure is zero, the diaphragm is passively tensed, and a residual small pleural pressure gradient may be present.

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.

Respiratory and Laryngeal Function During Whispering

1991 ◽  
Vol 34 (4) ◽  
pp. 761-767 ◽  
Author(s):  
Elaine T. Stathopoulos ◽  
Jeannette D. Hoit ◽  
Thomas J. Hixon ◽  
Peter J. Watson ◽  
Nancy Pearl Solomon
Keyword(s):  
Young Adults ◽  
Chest Wall ◽  
Voice Disorders ◽  
Normal Subjects ◽  
High Rate ◽  
Lung Volumes ◽  
Laryngeal Function ◽  
Tracheal Pressure ◽  
Lower Lung ◽  
Resistive Loads

Established procedures for making chest wall kinematic observations (Hoit & Hixon, 1987) and pressure-flow observations (Smitheran & Hixon, 1981) were used to study respiratory and laryngeal function during whispering and speaking in 10 healthy young adults. Results indicate that whispering involves generally lower lung volumes, lower tracheal pressures, higher translaryngeal flows, lower laryngeal airway resistances, and fewer syllables per breath group when compared to speaking. The use of lower lung volumes during whispering than speaking may reflect a means of achieving different tracheal pressure targets. Reductions in the number of syllables produced per breath group may be an adjustment to the high rate of air expenditure accompanying whispering compared to speaking. Performance of the normal subjects studied in this investigation does not resemble that of individuals with speech and voice disorders characterized by low resistive loads.

Gravity effects on upper airway area and lung volumes during parabolic flight

1998 ◽  
Vol 84 (5) ◽  
pp. 1639-1645 ◽  
Author(s):  
Maurice Beaumont ◽  
Redouane Fodil ◽  
Daniel Isabey ◽  
Frédéric Lofaso ◽  
Dominique Touchard ◽  
...  
Keyword(s):  
Lung Volume ◽  
Parabolic Flight ◽  
Upper Airway ◽  
Normal Subjects ◽  
Lung Volumes ◽  
Acoustic Reflection ◽  
Volume Functional ◽  
Airway Caliber ◽  
Gravity Effects ◽  
Residual Capacity

We measured upper airway caliber and lung volumes in six normal subjects in the sitting and supine positions during 20-s periods in normogravity, hypergravity [1.8 + head-to-foot acceleration (Gz)], and microgravity (∼0 Gz) induced by parabolic flights. Airway caliber and lung volumes were inferred by the acoustic reflection method and inductance plethysmography, respectively. In subjects in the sitting position, an increase in gravity from 0 to 1.8 +Gz was associated with increases in the calibers of the retrobasitongue and palatopharyngeal regions (+20 and +30%, respectively) and with a concomitant 0.5-liter increase in end-expiratory lung volume (functional residual capacity, FRC). In subjects in the supine position, no changes in the areas of these regions were observed, despite significant decreases in FRC from microgravity to normogravity (−0.6 liter) and from microgravity to hypergravity (−0.5 liter). Laryngeal narrowing also occurred in both positions (about −15%) when gravity increased from 0 to 1.8 +Gz. We concluded that variation in lung volume is insufficient to explain all upper airway caliber variation but that direct gravity effects on tissues surrounding the upper airway should be taken into account.

Effects of separate rib cage and abdominal restriction on exercise performance in normal humans

1985 ◽  
Vol 58 (6) ◽  
pp. 2020-2026 ◽  
Author(s):  
S. N. Hussain ◽  
B. Rabinovitch ◽  
P. T. Macklem ◽  
R. L. Pardy
Keyword(s):  
Minute Ventilation ◽  
Normal Subjects ◽  
Cycle Ergometer ◽  
Abdominal Muscle ◽  
Work Rate ◽  
Abdominal Pressure ◽  
Transdiaphragmatic Pressure ◽  
Rib Cage ◽  
Constant Work Rate ◽  
And Control

We assessed the effects of selective restriction of movements of the rib cage (Res,rc) and abdomen (Res,ab) on ventilatory pattern, transdiaphragmatic pressure (Pdi), and electrical activity of the diaphragm (Edi) in five normal subjects exercising at a constant work rate (80% of maximum power output) on a cycle ergometer till exhaustion. Restriction of movements was achieved by an inelastic corset applied tightly around the rib cage or abdomen. Edi was recorded by an esophageal electrode, rectified, and then integrated, and peak values during inspiration were measured. Each subject exercised at the same work rate on 3 days: with Res,rc, with Res,ab, and without restriction (control). Res,rc but not Res,ab reduced exercise time (tlim). Up to tlim, minute ventilation (VE) was similar in all three conditions. At any level of VE, however, Res,rc decreased tidal volume and inspiratory and expiratory time, whereas Res,ab had no effect on the pattern of breathing. Res,ab was associated with higher inspiratory Pdi swings at any level of VE, whereas peak Edi was similar to control. Inspiratory Pdi swings were the same with Res,rc as control, but the peak Edi for a given Pdi was greater with Res,rc (P less than 0.05). During Res,rc the abdominal pressure swings in expiration were greater than with Res,ab and control. We conclude that Res,rc altered the pattern of breathing in normal subjects in high-intensity exercise, decreased diaphragmatic contractility, increased abdominal muscle recruitment in expiration, and reduced tlim. On the other hand, Res,ab had no effect on breathing pattern or tlim but was associated with increased diaphragmatic contractility.

Sign in / Sign up

Export Citation Format

Share Document