Reversibility of Airways Obstruction in Chronic Bronchitis

1972 ◽  
Vol 42 (6) ◽  
pp. 725-733 ◽  
Author(s):  
T. W. Astin
Keyword(s):  
Muscle Contraction ◽  
Chronic Bronchitis ◽  
Lung Volume ◽  
Normal Subjects ◽  
Atropine Sulphate ◽  
Airways Obstruction ◽  
Chest Disease ◽  
Before And After ◽  
Airways Resistance ◽  
Intravenous Atropine

1. Airways resistance and lung volume were measured in twenty-five patients with chronic bronchitis and fifteen patients without chest disease before and after the inhalation of isoprenaline. Similar measurements were made on fourteen of these patients with chronic bronchitis and twelve other patients without chest disease before and after the intravenous injection of atropine sulphate. 2. There were significant decreases in airways resistance after isoprenaline inhalation and intravenous atropine both in patients with bronchitis and normal subjects but the decreases were greater in the patients with chronic bronchitis. 3. The decrease in resistance was proportional to the degree of initial airways resistance. 4. The results are considered to indicate that bronchial muscle contraction increases the airways resistance of patients with chronic bronchitis and contributes to the airways obstruction; its contribution increases with increasing severity of the condition. A significant part of the increased airways resistance in these patients is potentially reversible and nervously mediated.

Bronchial Sympathetic Activity in Chronic Bronchitis

1972 ◽  
Vol 43 (6) ◽  
pp. 881-889 ◽  
Author(s):  
T. W. Astin
Keyword(s):  
Chronic Bronchitis ◽  
Sympathetic Activity ◽  
Normal Subjects ◽  
Control Subjects ◽  
Chest Disease ◽  
Before And After ◽  
Alpha Receptors ◽  
Airways Resistance ◽  
Propranolol Administration ◽  
Made In

1. Measurements of airways resistance and lung volume were made in sixteen patients with chronic bronchitis and ten patients without chest disease before and after intravenous propranolol administration. 2. The airways resistance of the patients with chronic bronchitis increased significantly after propranolol administration but in the control subjects there was no significant increase. 3. In the patients with chronic bronchitis the increases in airways resistance were greater when the initial values were high. 4. In seven of the patients with chronic bronchitis and seven further control subjects airways resistance was measured before and after intravenous thymoxamine administration. 5. The airways resistance of the normal subjects was unchanged by thymoxamine administration, but that of the patients with chronic bronchitis decreased significantly. 6. The results are consistent with the existence of bronchial alpha receptors in man. In patients with chronic bronchitis there are greater degrees of both alpha and beta bronchial sympathetic activity than in normal subjects. The greater the severity of the condition the greater is the degree of beta sympathetic activity. In considering the factors causing airways obstruction in chronic bronchitis sympathetic activity should be taken into account.

scholarly journals Lung elastic recoil during breathing at increased lung volume

1999 ◽  
Vol 87 (4) ◽  
pp. 1491-1495 ◽  
Author(s):  
Joseph R. Rodarte ◽  
Gassan Noredin ◽  
Charles Miller ◽  
Vito Brusasco ◽  
Riccardo Pellegrino ◽  
...  
Keyword(s):  
Stress Relaxation ◽  
Tidal Volume ◽  
Lung Volume ◽  
Normal Subjects ◽  
Dynamic Hyperinflation ◽  
Airway Closure ◽  
Elastic Recoil ◽  
Volume Increase ◽  
Before And After ◽  
Residual Capacity

During dynamic hyperinflation with induced bronchoconstriction, there is a reduction in lung elastic recoil at constant lung volume (R. Pellegrino, O. Wilson, G. Jenouri, and J. R. Rodarte. J. Appl. Physiol. 81: 964–975, 1996). In the present study, lung elastic recoil at control end inspiration was measured in normal subjects in a volume displacement plethysmograph before and after voluntary increases in mean lung volume, which were achieved by one tidal volume increase in functional residual capacity (FRC) with constant tidal volume and by doubling tidal volume with constant FRC. Lung elastic recoil at control end inspiration was significantly decreased by ∼10% within four breaths of increasing FRC. When tidal volume was doubled, the decrease in computed lung recoil at control end inspiration was not significant. Because voluntary increases of lung volume should not produce airway closure, we conclude that stress relaxation was responsible for the decrease in lung recoil.

The Interpretation of Different Measurements of Airways Obstruction in the Presence of Lung Volume Changes in Bronchial Asthma

1978 ◽  
Vol 54 (3) ◽  
pp. 313-321
Author(s):  
K. B. Saunders ◽  
M. Rudolf
Keyword(s):  
Lung Volume ◽  
Time Course ◽  
Forced Expiratory Volume ◽  
Specific Conductance ◽  
Volume Changes ◽  
Lung Volumes ◽  
Bronchodilator Response ◽  
Before And After ◽  
Residual Capacity ◽  
Airways Resistance

1. We measured changes in peak expiratory flow rate (PEFR), forced expiratory volume in 1 s (FEV1·0), airways resistance (Raw), specific conductance (sGaw), residual volume (RV), functional residual capacity (FRC) and total lung capacity (TLC) in 44 patients with asthma. 2. When asthma was induced by exercise in five patients there were large changes in volumes, but these did not obscure changes in PEFR, which adequately defined the time course of the response. 3. In 70 comparisons before and after inhalation of bronchodilator drug in 33 asthmatic subjects, the responses were classified by the size of the change in lung volumes, which showed a concordant improvement, or no change, in 61 comparisons. Despite these lung volume changes, measurement of both PEFR and FEV1·0, would have detected a bronchodilator response in all but two cases. 4. In 81 comparisons in 23 subjects over time intervals varying from 1 day to 11 months, lung volumes changed in concordance with PEFR and FEV1·0 in 59. In eight of these comparisons, measurement of lung volumes would have altered our interpretation of the changes in PEFR and FEV1·0. 5. In the same 81 comparisons changes in airways resistance were concordant with changes in PEFR and FEV1·0 on 44 occasions, with minor discordant changes in 19. We could not explain the remaining 18 cases showing major discordance between these two types of measurement of airway calibre. 6. We conclude that both FEV1·0, and PEFR should be used for detection of a bronchodilator response, and that measurement of lung volumes will rarely contribute to the interpretation. Over longer periods, lung volumes should be measured if possible. We found no practical use for routine measurement of airways resistance in patients with asthma.

Use of magnetometers to volume-reference flow-volume curves

1980 ◽  
Vol 48 (4) ◽  
pp. 731-736 ◽  
Author(s):  
D. Goldstein ◽  
J. Mead
Keyword(s):  
Standard Deviation ◽  
Lung Volume ◽  
Marked Point ◽  
Normal Subjects ◽  
Forced Oscillations ◽  
Flow Volume ◽  
Reference Flow ◽  
Before And After ◽  
Conductance Increase ◽  
Excellent Reproducibility

Chest wall diameters measured by magnetometers were used to indicate a lung volume reference for repeated interrupted partial flow-volume curves (IPFVC's) and IPFVC's, and total respiratory conductances were measured before and after bronchodilation in normals. With posture rigidly controlled, subjects matched the magnetometer display on an X-Y oscilloscope to a previously marked point on the screen. Seven subjects performed six inspiratory capacities (IC's) from the reference point, completely reposturing before each maneuver. For a mean IC of 2.25 liters the standard deviation was 5.5%. IPFVC's were performed through a valve system triggering open at 60 cmH2O and shutting after 1 liter of expiration. Ten subjects each performed five sets of IPFVC's volume-referenced by magnetometers and the pooled flow variability was 5% or 0.15 l/s. Respiratory conductances by forced oscillations and IPFVC's were measured in five normal subjects before and after inhaled isoproterenol. In each subject the flow increase was always greater than the conductance increase (about 2.5:1.0) for P less than 0.05. We conclude that magnetometers may be used in normals to volume-reference IPFVC's with excellent reproducibility.

The Retention of Lung Secretions during the Night in Normal Subjects

1978 ◽  
Vol 55 (6) ◽  
pp. 523-527 ◽  
Author(s):  
J. R. M. Bateman ◽  
D. Pavia ◽  
S. W. Clarke
Keyword(s):  
Diurnal Variation ◽  
Chronic Bronchitis ◽  
Mucociliary Clearance ◽  
Normal Subjects ◽  
Early Morning ◽  
Normal Male ◽  
Related Phenomenon ◽  
Before And After ◽  
Male Subjects

1. Mucociliary clearance has been measured over a 6 h period by using the radioaerosol technique in seven normal male subjects lying supine, both during the day when awake, and during the night when asleep. 2. The percentage of radioaerosol cleared during the night, when asleep, was significantly less than during the day when awake (P < 0.02). 3. A comparison of radioaerosol clearance before and after the time of onset of sleep demonstrates that reduced clearance occurred during sleep, indicating that this is probably a sleep-related phenomenon and not merely a result of diurnal variation. 4. This finding has important implications for patients with chronic bronchitis or asthma, in whom early morning cough or wheeze may be a predominant feature.

Effect of 30% Oxygen on Local Matching of Perfusion and Ventilation in Chronic Airways Obstruction

1977 ◽  
Vol 53 (4) ◽  
pp. 387-395 ◽  
Author(s):  
Noemi M. Eiser ◽  
Hazel A. Jones ◽  
J. M. B. Hughes
Keyword(s):  
Chronic Bronchitis ◽  
Minute Ventilation ◽  
Normal Subjects ◽  
Systematic Change ◽  
Lung Field ◽  
Arterial Pco2 ◽  
Oxygen Breathing ◽  
Airways Obstruction ◽  
Hypoxic Vasoconstriction ◽  
Change In The Mean

1. Sixteen patients with chronic bronchitis and airways obstruction were given radioactive nitrogen (13N) by intravenous injection and by inhalation, while breathing air and after 10–20 min breathing 30% oxygen. The clearance of 13N from four zones of each patient's whole lung field was monitored. 2. The 13N clearance of each region in these patients with chronic bronchitis was much slower than in normal subjects. Oxygen breathing produced a significant delay in the clearance of intravenously administered 13N in 23 zones in 10 patients but no systematic change in clearance after inhaled 13N. 3. With inhalation of 30% oxygen there was no significant change in the mean minute ventilation, tidal volume or arterial Pco2. 4. The results suggest that local hypoxic vasoconstriction is present in some patients on breathing air and that this is relieved by 30% oxygen, resulting in a diversion of local blood flow from well-ventilated to more poorly ventilated areas. The fall in V̇A/Q̇ on 30% oxygen is insufficient to increase arterial Pco2.

The Effect of Stapedectomy on the Loudness of One’s Own Voice

1965 ◽  
Vol 8 (3) ◽  
pp. 223-234 ◽  
Author(s):  
William Melnick
Keyword(s):  
Middle Ear ◽  
Normal Subjects ◽  
Sound Energy ◽  
Loudness Function ◽  
Before And After ◽  
Increased Sensitivity

Five subjects with normal middle ear mechanisms, and otosclerotic patients, before and after stapedectomy, matched the loudness of their voices to the loudness of a 125-cps-sawtooth noise. The results showed loudness matching functions with gradual slopes, less than 1.00, for the normal subjects and the patients prior to stapedectomy. Post-surgically, the loudness function for the patients increased in steepness to considerably more than 1.00. These results are explained, most logically, in terms of increased sensitivity of the altered middle ear to sound energy generated by the listener’s own voice.

BESTIMMUNG DER INSULINAKTIVITÄT IM MENSCHLICHEM SERUM NACH GLUKOSEBELASTUNG ALS PRÜFUNG DER FUNKTIONSFÄHIGKEIT DES PANKREAS

1963 ◽  
Vol 42 (3) ◽  
pp. 437-452 ◽  
Author(s):  
H. Daweke
Keyword(s):  
Blood Sugar ◽  
Pancreatic Insufficiency ◽  
Normal Subjects ◽  
Insulin Binding ◽  
Epididymal Adipose Tissue ◽  
Moderate Increase ◽  
Glucose Loading ◽  
Before And After ◽  
Oral Hypoglycaemic Drugs ◽  
Severity Of The Disease

Using the method of glucose-1-14C oxydation to 14CO2 on the rat epididymal adipose tissue, the insulin-like activities (ILA) in the serum have been compared before and after oral loading with glucose in normal subjects, in maturity-onset diabetics and in insulin-requiring diabetics. In maturity-onset diabetics mean fasting values were found to be 30% below normal while in insulin-requiring diabetics they were 85% above normal. In normal subjects there was observed, 30 minutes after glucose loading, a moderate increase in blood sugar together with an increase of ILA of 222% above the starting value; in maturity-onset diabetics the increase in ILA was only 106% while the blood sugar was markedly increased. After glucose loading in maturity-onset diabetics, the total amount of insulin detected during the period of the experiment was, on the average, only 45% of that found in normal subjects. In insulin requiring diabetics there was no increase but, on the contrary, a steady decrease of the ILA values, while the blood sugar excessively increased. In general ILA values were higher than those in maturity-onset diabetics. No difference in response was found between maturity-onset diabetics treated with diet alone and those treated with diet and oral hypoglycaemic drugs. In contrast to the absolute ILA values, the index of insulin reserve, is of value in assessing the functional capacity of the pancreas. This index decreases progressively with the severity of the disease and reaches a maximum of 54% of the normal in maturity-onset diabetics, which can satisfactorily be explained by pancreas insufficiency. Only in some cases of insulin-requiring diabetics was an insulin reserve still detectable. The biological inactivity of the insulin circulating in the blood can be deduced from the increased ILA-values, as compared with those found in maturity-onset diabetics. Obviously some of this insulin can be released by the addition of glucose. It is likely that, in addition to pancreatic insufficiency, insulin-binding or insulin-inactivating antibodies play a part in the pathogenesis of insulin-requiring diabetes.

DETERMINATION OF BLOOD CORTICOIDS USING THE IN VITRO RESIN UPTAKE OF 3H-PREDNISOLONE

1968 ◽  
Vol 57 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Hironori Nakajima ◽  
Mitsunori Murala ◽  
Masumitsu Nakata ◽  
Takeshi Naruse ◽  
Seiji Kubo
Keyword(s):  
Thyroid Function Test ◽  
Normal Subjects ◽  
Adrenal Function ◽  
Function Test ◽  
Before And After ◽  
Adrenal Response ◽  
Suppression Test

ABSTRACT The in vitro resin uptake of 3H-prednisolone was used for the determination of blood cortisol after addition of radioactive prednisolone followed by Amberlite CG 400 Type 1 to the test serum, and incubation of the mixture. The radioactivity of the supernatant was compared before and after the addition of the resin. The principle of this method is similar to that of the 131I-triiodothyronine resin uptake for the thyroid function test. The tests for the specificity, reproducibility and sensitivity gave satisfactory results. The mean basal value ± SD of the 3H-prednisolone resin uptake was 35.3 ± 9.2% in normal subjects, and 27.1 ± 4.8% in pregnant women. This method was valid in various adrenal function tests, i. e. the adrenal circadian rhythm, corticotrophin (ACTH) test, dexamethasone suppression test and the adrenal response to lysine-8-vasopressin. It proved to be a sensitive indicator of the adrenal function. These results suggest that this method should be useful for a routine adrenal function test.

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