Relationship of increased breath-holding diffusing capacity to ventilation in exercise

1963 ◽  
Vol 18 (4) ◽  
pp. 794-797 ◽  
Author(s):  
Joseph C. Ross ◽  
Ronald W. Reinhart ◽  
John F. Boxell ◽  
Leroy H. King
Keyword(s):  
Steady State ◽  
Ventilation Rate ◽  
The Other ◽  
Breath Holding ◽  
Diffusing Capacity ◽  
Voluntary Hyperventilation ◽  
Pulmonary Diffusing Capacity ◽  
Pulmonary Capillaries ◽  
The Mean ◽  
Relationship Of

Pulmonary diffusing capacity (Dl), as measured by all techniques, increases with exercise possibly due to an increase in the volume of blood in pulmonary capillaries (Vc), but the mechanism for the latter is not known. Previous studies have indicated that the steady-state Dl can be increased by hyperventilation alone, enough possibly to account for the increase in Dl as measured by this method with exercise. On the other hand, breath-holding Dl is not increased by voluntary hyperventilation preceding the measurement. The present study was carried out to determine whether or not the increase in ventilation rate is a necessary part of a combination of factors which account for the rise in Dl during exercise. In this study breath-holding Dl was measured in five subjects. All of the five subjects studied had an increase in Dl during exercise when ventilation was voluntarily restrained to the resting level, and the mean increase was as great as the mean increase during the same amount of exercise with normal unrestricted breathing. The increase in Dl when breathing was restricted during exercise could not be accounted for by differences in alveolar volumes or by differences in alveolar O2 and CO2 tensions in the two situations. This study demonstrates that increase in ventilation preceding the measurement is not a determinant of the increase in breath-holding Dl with exercise Submitted on January 7, 1963

DlCO measurements with gas chromatography

1962 ◽  
Vol 17 (6) ◽  
pp. 856-860 ◽  
Author(s):  
Josef R. Smith ◽  
Lyle H. Hamilton
Keyword(s):  
Gas Chromatography ◽  
Normal Subjects ◽  
Inert Gas ◽  
Breath Holding ◽  
Gas Mixture ◽  
Diffusing Capacity ◽  
Gas Chromatograph ◽  
Excellent Correlation ◽  
Pulmonary Diffusing Capacity ◽  
The Mean

A gas chromatograph has been used to analyze gases for the measurement of pulmonary diffusing capacity using the breath-holding technique. The gas mixture used for the measurement consisted of carbon monoxide in air with neon as the insoluble inert gas. The calculated DlCO was unaffected when sulphur hexafloride (SF6) or He was substituted for Ne in the mixture, but since CO and Ne could be most simply and rapidly analyzed, this combination was preferred for the gas mixture used to measure DlCO. The mean DlCO for ten normal subjects was 25.8 ± 4.2 ml/min mm Hg. These results were comparable to values reported in the literature when established methods of analysis were used. An excellent correlation was found between calculated DlCO and the clinical condition of patients with impaired pulmonary diffusing capacity. Submitted on February 14, 1962

Effect of atropine and reserpine on pulmonary diffusing capacity during exercise in man

1964 ◽  
Vol 19 (3) ◽  
pp. 465-468 ◽  
Author(s):  
Richard A. Krumholz ◽  
Joseph C. Ross
Keyword(s):  
Breath Holding ◽  
Diffusing Capacity ◽  
Significance Level ◽  
Pulmonary Diffusing Capacity ◽  
Pulmonary Diffusion ◽  
Pulmonary Capillary ◽  
Exercise Period ◽  
Capillary Bed

Pulmonary diffusing capacity increases with exercise. The rapidity of this increase after the onset of exercise and factors which may alter it, i.e. atropine (2.0 mg i.v.) and reserpine (0.5 mg/day p.o. for 7 days), were investigated. Breath-holding Dl determinations were made before exercise began, at 0–10 sec of exercise, after 1, 2, and 3 min of exercise, and 3 min after the end of exercise. Dl was already strikingly increased at 0–10 sec of exercise, although further increases occurred during the 3-min exercise period. Following atropine administration in nine subjects the immediate rise in Dl at 0–10 sec of exercise was significantly reduced (P < 0.01), but the increases with further exercise were not significantly altered. After the reserpine administration in six subjects, the 0–10 sec exercise Dl values tended to be lower, but not to a significance level of <.05, and there was a tendency toward lower Dl values throughout the 3-min exercise period. This study suggests, then, that the immediate and the later increases in Dl with exercise are produced by two different mechanisms. pulmonary diffusion; pulmonary diffusion in exercise; mechanism for increased diffusion in exercise; pulmonary capillary bed Submitted on September 23, 1963

THE SINGLE BREATH DIFFUSING CAPACITY AND THE PERMEABILITY OF THE LUNGS OF NORMAL MAN

1963 ◽  
Vol 41 (1) ◽  
pp. 1283-1292
Author(s):  
Edith Rosenberg
Keyword(s):  
Molecular Sieve ◽  
The Other ◽  
Breath Holding ◽  
Diffusing Capacity ◽  
Alveolar Volume ◽  
Lung Volumes ◽  
Test Gas ◽  
Single Breath ◽  
Normal Man ◽  
Molecular Sieve Column

The single breath diffusing capacity for CO, DL, and the permeability of the lungs, K, were measured in six male and two female medical students at various lung volumes. The subjects rested 15 minutes before each test and the expired alveolar volume as well as breath-holding time and inspired volume were recorded on a spirogram. The test gas used consisted of 0.3% CO, 0.3% SF6, 20% O2, and the balance N2. The sample of alveolar gas expired after breath-holding was analyzed for CO and SF6 on a vapor fractometer using a 2-meter molecular sieve column. DL varied with the surface area of the subjects as well as with the alveolar volume at which the test was performed. K, on the other hand, was independent of the size of the subjects and decreased towards a constant value as lung volume became large. K should, therefore, be more reproducible than DL. The average permeability of the eight subjects used in this study was 0.0715 ml CO per second per ml of alveolar volume. In every experiment, alveolar volumes were also calculated from the SF6 dilution. These values, VD, were compared to alveolar volumes calculated from the maximum lung volumes, VA. For the males there was no measurable difference between alveolar volumes calculated by these two methods when 2 liters or more of test gas were inspired. It is suggested that the replacement of the measurement of DL in pulmonary function laboratories by an evaluation of K and VD may transform the single breath diffusing capacity test into a useful diagnostic tool.

Some effects of carbon dioxide on foreign gas uptake

1959 ◽  
Vol 14 (3) ◽  
pp. 333-338 ◽  
Author(s):  
Roy J. Shephard
Keyword(s):  
Carbon Dioxide ◽  
Normal Subjects ◽  
Minute Volume ◽  
Breath Holding ◽  
Analogue Computer ◽  
Diffusing Capacity ◽  
Gas Uptake ◽  
Consistent Change ◽  
The Mean ◽  
Nonuniform System

Partitional respirometry in normal subjects breathing 1-5% CO2 indicates a large increase of alveolar dead space, but in the steady state there is no consistent change of diffusing capacity or effective pulmonary blood flow. An apparent early decrease of diffusing capacity is probably an artefact due to difficulties in measuring acetylene uptake with a changing respiratory minute volume, and if Dco is measured by the breath-holding technique, carbon dioxide produces no immediate effect. Hypercapnic hyperventilation does not help in making acetylene uptake conform to a single exponential curve. The ventilatory efficiency indicated by partitional respirometry in a nonuniform system is dependent on both solubility of the test gases and the mean Va/Q ratio. An analogue computer for the solution of Va/Q problems is described. Submitted on August 18, 1958

Influence of pressure suit inflation on pulmonary diffusing capacity in man

1962 ◽  
Vol 17 (2) ◽  
pp. 259-262 ◽  
Author(s):  
Joseph C. Ross ◽  
Glen D. Ley ◽  
Ronald F. Coburn ◽  
J. L. Eller ◽  
Robert E. Forster
Keyword(s):  
Valsalva Maneuver ◽  
Breath Holding ◽  
Entire Body ◽  
Costal Margin ◽  
Pulmonary Congestion ◽  
Diffusing Capacity ◽  
Thoracic Cage ◽  
Alveolar Volume ◽  
Air Trapping ◽  
Pulmonary Diffusing Capacity

Previous investigations of the effect of inflation of a pressure suit on pulmonary diffusing capacity (DL) have been reported from our two laboratories, one (Indianapolis) finding an increase and the other (Philadelphia) finding no change. The present investigation was carried out in Philadelphia, using some of the same subjects and pressure suits in order to reconcile the contradictory results. The earlier contradictory results were confirmed. The pressure suit used in the investigations at Philadelphia ( suit P)covered the entire body below the nipples, whereas the suit used in the investigations at Indianapolis( suit I) extended cephalad only as far as the costal margin. When suit P was inflated in the present study, DL again did not increase significantly in two subjects. However, when the upper part of the suit was folded down so that the thoracic cage was not covered, inflation of the suit did produce a significant increase in DL. Inflation of suit P when it covered the chest made it difficult for a subject not to perform a Valsalva maneuver during breath holding and caused more decrease in alveolar volume (Va) than when it was inflated in the folded-down position. In two subjects studied, we found no difference in air trapping with inflation of suit P in the two positions. The discrepancy between the results of the two earlier studies appears to have resulted from the different construction of the two pressure suits used. We conclude that pressure suit inflation in man will produce an increase in DL, presumably by means of pulmonary congestion. Submitted on September 22, 1961

Effect of exercise on pulmonary diffusing capacity

1963 ◽  
Vol 18 (3) ◽  
pp. 447-456 ◽  
Author(s):  
G. M. Turino ◽  
E. H. Bergofsky ◽  
R. M. Goldring ◽  
A. P. Fishman
Keyword(s):  
Carbon Monoxide ◽  
Young Adults ◽  
Steady State ◽  
Body Position ◽  
Diffusing Capacity ◽  
Pulmonary Diffusing Capacity ◽  
Graded Exercise ◽  
Normal Man ◽  
The Difference

The effect of graded exercise on the pulmonary diffusing capacity for both oxygen and carbon monoxide measured simultaneously was studied in healthy young adults by steady-state methods. Pulmonary diffusing capacity for oxygen increases progressively with increasing severity of exercise; it exceeds the DlCO at high levels of exercise by amounts greater than can be accounted for by the difference in diffusivity of the test gases. Diffusing capacity for carbon monoxide increases less than DlOO2 for comparable grades of exercise but no definite plateau value could be established. The supine or upright body position does not influence the values of either DlOO2 or DlCO during exercise. Diffusing capacity of the lung for oxygen does not limit the maximum levels of exercise which may be achieved by normal man. Submitted on August 6, 1962

Longevity ofEchinostoma caproniin Balb/c mice

2008 ◽  
Vol 82 (1) ◽  
pp. 95-96 ◽  
Author(s):  
B. Fried ◽  
R.C. Peoples
Keyword(s):  
The Other ◽  
Term Survival ◽  
Long Term Survival ◽  
Echinostoma Caproni ◽  
Host Parasite Relationship ◽  
Parasite Relationship ◽  
The Mean ◽  
Host Parasite ◽  
Relationship Of

AbstractThis study used Balb/c mice to examine the longevity ofEchinostoma caproni. Five mice each exposed to 75 encysted metacercariae (cysts) were necropsied at 23 weeks postinfection (PI) (160 days PI). Two of the 5 were infected with a total of 33 worms; 23 in one mouse and 10 in the other. Body and organ area measurements showed that these worms were robust and normal in appearance. No signs of atrophy of any of the genital structures were observed. The mean ± SE of eggs/uterus per worm (n = 10) was 243 ± 6. This strain of mouse will be suitable to study the effect of long-term survival on the host–parasite relationship ofE. caproniin Balb/c mice.

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