Bronchial Provocation in the Study of Sensations Associated with Disordered Breathing

1977 ◽  
Vol 52 (4) ◽  
pp. 423-428
Author(s):  
A. R. Rubinfeld ◽  
M. C. F. Pain
Keyword(s):  
Airway Resistance ◽  
Flow Volume ◽  
Lung Volumes ◽  
Similar Symptom ◽  
Bronchial Provocation ◽  
Disordered Breathing

1. Lung volumes, airway resistance and flow/volume curves were measured in ten asthmatic subjects at times when tightness in the chest was just sensed (threshold symptom). 2. These measurements when the threshold symptom was induced by methacholine inhalation were compared with those when a similar symptom occurred spontaneously, in the same subjects. 3. Values during the methacholine-induced thresholds were very similar to those observed when threshold symptoms developed spontaneously. 4. Controlled bronchial provocation mimics spontaneous asthma sufficiently well to allow this technique to be used in the study of sensations associated with breathing. This has some advantages over the already established models utilizing external hindrances to breathing.

scholarly journals To the informative value of flow-volume curve in forced expiration

2008 ◽  
pp. 91-97 ◽  
Author(s):  
G. A. Lyubimov ◽  
I. M. Skobeleva ◽  
G. M. Sakharova ◽  
A. V. Suvorov
Keyword(s):  
Airway Resistance ◽  
Lung Compliance ◽  
Forced Expiration ◽  
Flow Volume ◽  
Functional Tests ◽  
Lung Volumes ◽  
Volume Curve ◽  
Quitting Smoking ◽  
Flow Volume Curve ◽  
Airway Walls

This report introduces a mathematical model of forced expiration to analyze pulmonary function. Results of 3-year lung function monitoring of an ex-smoker have been shown in the paper. Actual values of lung volumes and airway resistance were used for modeling. The computerized data were compared to the flow-volume curve parameters and lung volumes measured during the forced expiration. Weak correlation between the "flow-volume" curve parameters and the time after quitting smoking together with significant change in the lung volumes and the airway resistance seen in the study could be due to some processes which have not been followed in this study (lung compliance, airway resistance at forced expiration, and elastic properties of airway walls).The results demonstrated that mathematical models could increase informative value of pulmonary functional tests. In addition, the model could emphasize additional functional tests for better diagnostic usefulness of functional investigations.

Flow-Volume Curves in Infants with Lung Disease

PEDIATRICS ◽  
1983 ◽  
Vol 72 (4) ◽  
pp. 517-522
Author(s):  
S. Godfrey ◽  
E. Bar-Yishay ◽  
I. Arad ◽  
L. I. Landau ◽  
L. M. Taussig
Keyword(s):  
Lung Disease ◽  
Airway Obstruction ◽  
Lung Volume ◽  
Airway Resistance ◽  
Whole Body ◽  
Small Airways ◽  
Forced Expiration ◽  
Flow Volume ◽  
Complete Evaluation ◽  
Expiratory Flow

Partial expiratory flow-volume maneuvers have been performed on nine occasions on six infants with a variety of pulmonary problems using a new tech nique for thoracic compression. The infants were placed within an inflatable bag that was, itself, within a canvas bag. By sudden controlled inflation of the inner bag at end inspiration, partial expiratory flow-volume curves were generated and recorded by means of a face mask and pneumotachograph. By comparing these flow results with those airway resistance and lung volume measurements obtained from the infants in whole body plethysmography and by noting the effect of inhaling a helium/oxygen gas mixture, it was possible to partition the airway obstruction between large and small airways. The presence of small airway obstruction was noted in the absence of changes in airway resistance or lung volume in several instances. A complete evaluation of airway function should include this test of forced expiration for greater understanding and treatment of lung disease in infancy.

The bronchodilator test in patients with airway obstruction: the responsiveness of lung function parameters

2021 ◽  
pp. 57-61
Author(s):  
M. I. Chushkin ◽  
L. A. Popova ◽  
E. A. Shergina ◽  
N. L. Karpina
Keyword(s):  
Pulmonary Function ◽  
Airway Obstruction ◽  
Airway Resistance ◽  
Lung Volumes ◽  
Before And After ◽  
Calculated Effect ◽  
Volume Measurements ◽  
The Difference ◽  
Bronchodilator Responsiveness ◽  
Chronic Airway

Interpretation of bronchodilator (BD) test based on reaction of forced expiratory in one second (FEV 1). For assessing bronchodilator responsiveness of lung volumes, airway resistance remains largely unexplored. Therefore, we assessed the response of pulmonary function parameters to BD to reveal the most responsive parameter. 90 patients with chronic airway obstruction (61 male and 29 female; aged 55±11; post-  BD FEV 1 was 63.1+18.3 % predicted) performed spirometry and static lung volume measurements before and after inhalation of BD. We calculated effect size (ES) for each parameter from the difference between two means divided by the standard deviation of baseline score. There was a significant increase both FVC and FEV 1by 8.2 and 12.3 % from baseline (p<0.001). ES were 0.34 for FEV1 and 0.26 for FVC. The ES for lung volumes were from -0.07 (total lung capacity) to -0.31 (residual volume). The ES for sRtot (specific airway resistance) was -0.5 and ES for sGeff (specific effective airway conductance) was 0.95. The parameters of airway resistance and conductance were more responsive for the assessment of pulmonary function changes than spirometry and lung volumes parameters in patients with chronic airway obstruction.

scholarly journals Post-Operative Flow-Volume Loops

1977 ◽  
Vol 5 (2) ◽  
pp. 146-148 ◽  
Author(s):  
A. Morton ◽  
P. Hansen ◽  
A. B. Baker
Keyword(s):  
Flow Volume ◽  
Lung Volumes ◽  
Flow Rates ◽  
Lower Flow

A study of flow-volume curves pre- and post-operatively demonstrated a marked difference between bronchitic and non-bronchitic patients. All bronchitic patients showed lower flow rates at low lung volumes post-operatively, when compared with their pre-operative values. Non-bronchitic patients all had higher flow rates for the same comparison.

Effect of lung volume on forced expiratory flows during rapid thoracoabdominal compression in infants

1995 ◽  
Vol 78 (5) ◽  
pp. 1993-1997 ◽  
Author(s):  
J. Hammer ◽  
C. J. Newth
Keyword(s):  
Lung Volume ◽  
Vital Capacity ◽  
Forced Expiration ◽  
Flow Volume ◽  
Older Children ◽  
Lung Volumes ◽  
Volume Segment ◽  
Forced Expiratory Flow ◽  
Residual Capacity ◽  
End Tidal

The rapid thoracoabdominal compression (RTC) technique is commonly used in pulmonary function laboratories to assess flow-volume relationships in infants unable to produce a voluntary forced expiration maneuver. This technique produces forced expiratory flows over only a small lung volume segment (i.e., tidal volume). It has been argued that the RTC technique should be modified to measure flow-volume relationships over a larger portion of the vital capacity range to imitate the voluntary maximal forced expiratory maneuver obtained in older children and adults. We examined the effect of volume history on forced expiratory flows by generating forced expiratory flow-volume curves by RTC from well-defined inspiratory volumes delineated by inspiratory pressures of 10, 20, 30, and 40 cmH2O down to residual volume (i.e., the reference volume) in seven intubated and anesthetized infants with normal lungs [age 8.0 +/- 2.0 (SE) mo, weight 6.7 +/- 0.6 kg]. We compared maximal expiratory flows at isovolume points (25 and 10% of forced vital capacity) and found no significant differences in maximal isovolume flow rates measured from the different lung volumes. We conclude that there is no obvious need to initiate RTC from higher lung volumes if the technique is used for flow comparisons. However, compared with measurements of maximal flows at functional residual capacity by RTC from end-tidal inspiration, the initiation of RTC from a defined and reproducible inspiratory level appears to decrease the intrasubject variability of the maximal expiratory flows at low lung volumes.

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