Effects of fever on pulmonary diffusing capacity and pulmonary mechanics in man

1963 ◽  
Vol 18 (6) ◽  
pp. 1065-1070 ◽  
Author(s):  
Leon Cander ◽  
Ernest G. Hanowell
Keyword(s):  
Pulmonary Blood Flow ◽  
Minute Volume ◽  
Lung Mechanics ◽  
Breath Holding ◽  
Pulmonary Mechanics ◽  
Diffusing Capacity ◽  
Oral Temperature ◽  
Pulmonary Resistance ◽  
Pulmonary Diffusing Capacity ◽  
Normal Adults

Measurements of oral temperature, pulse rate, blood pressure, expired minute volume (Ve), respiratory rate (f), O2 consumption (Vo2), CO2 excretion (Vco2), breath-holding pulmonary diffusing capacity (DlCO), dynamic pulmonary compliance (Cdyn), and total pulmonary resistance were made on six normal adults before and at regular intervals over an 8-hr period following the induction of fever with triple typhoid vaccine. Although Ve, f, Vo2 increased during the chill, flush, and defervescence phases of fever, there was no significant change in Cdyn and total pulmonary resistance. Of interest was the slight, though statistically significant decrease in DlCO during the flush and defervescence phases. Results suggest a low temperature coefficient for the mechanical properties of the lung in the range studied. The absence of an increased DlCO during the flush phase of fever when Ve and the cardiac output are known to increase suggests that ventilation and pulmonary blood flow are not important determinants of DlCO. lung mechanics; ventilation Submitted on February 18, 1963

Mechanism of arterial hypoxemia following pulmonary thromboembolism in dogs

1975 ◽  
Vol 39 (1) ◽  
pp. 41-46 ◽  
Author(s):  
S. E. Levy ◽  
D. H. Simmons
Keyword(s):  
Pulmonary Thromboembolism ◽  
Minute Volume ◽  
Lung Mechanics ◽  
Diffusing Capacity ◽  
Pulmonary Resistance ◽  
Arterial Hypoxemia ◽  
Single Breath ◽  
Before And After ◽  
Pulmonary Embolization

Mongrel dogs (29) were anesthetized, paralyzed, and ventilated at a constant minute volume. AaD02 breathing air and 100% O2, venous admixture breathing air (Qva/Qt) and 100% O2 (Qs/Qt), single-breath diffusing capacity for CO (DLCO), and total pulmonary resistance (RL) and pulmonary compliance (CL) were measured before and after pulmonary embolization with autologus in vivo venous thrombi. Nine dogs were heparinized before embolization. In the 20 nonheparinized dogs AaDo2 breathing air increased from 11 to 26 mmHg, Qva/Qt from 4 to 22%, and Qs/At from 5 to 8%. DLCO decreased 24%, RL increased 43%, and CL fell 30%. In the nine heparinized dogs AaDo2 breathing air increased from 8 to 13 mmHg and Qva/Qt from 3 to 8%; Qs/Qt did not change. DLCO decreased 31%; RL and CL did not change significantly. The increase in Qva/Qt of 5% in the heparinized dogs was significantly less (P smaller than 0.001) than the increase of 18% in the nonheparinized dogs. These findings suggest that arterial hypoxemia following thromboembolism is due to ventilation-perfusion inequality caused by changes in lung mechanics.

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

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

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

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

scholarly journals Lung function during and after prolonged head-down bed rest

2002 ◽  
Vol 92 (1) ◽  
pp. 75-83 ◽  
Author(s):  
Stéphanie Montmerle ◽  
Jonas Spaak ◽  
Dag Linnarsson
Keyword(s):  
Pulmonary Blood Flow ◽  
Respiratory Muscle ◽  
Bed Rest ◽  
Lung Mechanics ◽  
Central Blood Volume ◽  
Diffusing Capacity ◽  
Elastic Recoil ◽  
Alveolar Volume ◽  
Supine Posture ◽  
Time Courses

We determined the effects of prolonged head-down tilt bed rest (HDT) on lung mechanics and gas exchange. Six subjects were studied in supine and upright postures before (control), during [ day 113(D113)], and after (R + number of days of recovery) 120 days of HDT. Peak expiratory flow (PF) never differed between positions at any time and never differed from controls. Maximal midexpiratory flow (FEF25–75%) was lower in the supine than in the upright posture before HDT and was reduced in the supine posture by about 20% between baseline and D113, R + 0, and R + 3. The diffusing capacity for carbon monoxide corrected to a standardized alveolar volume (volume-corrected Dl CO) was lower in the upright than in the supine posture and decreased in both postures by 20% between baseline and R + 0 and by 15% between baseline and R + 15. Pulmonary blood flow (Q˙C) increased from R + 0 to R + 3 by 20 (supine) and 35% (upright). As PF is mostly effort dependent, our data speak against major respiratory muscle deconditioning after 120 days of HDT. The decrease in FEF25–75% suggests a reduction in elastic recoil. Time courses of volume-corrected Dl CO andQ˙C could be explained by a decrease in central blood volume during and immediately after HDT.

Pulmonary diffusing capacity and capillary blood flow during forward acceleration

1965 ◽  
Vol 20 (6) ◽  
pp. 1199-1204 ◽  
Author(s):  
Gordon G. Power ◽  
Richard W. Hyde ◽  
Raymond J. Sever ◽  
Frederic G. Hoppin ◽  
Jean R. Nairn
Keyword(s):  
Blood Flow ◽  
Arterial Oxygen Saturation ◽  
Capillary Blood ◽  
Capillary Blood Flow ◽  
Arterial Oxygen ◽  
Breath Holding ◽  
Diffusing Capacity ◽  
Pulmonary Diffusing Capacity ◽  
Control Value ◽  
Initial Control

We studied possible causes of the decreased arterial oxygen saturation seen when a subject is accelerated in a centrifuge by measuring simultaneously the pulmonary diffusing capacity, DlCO, and the effective pulmonary capillary blood flow, Qc, using breath-holding techniques with carbon monoxide and acetylene. After 1 min of forward ("eyeballs in") acceleration at eight times normal gravity, 8 G, average Dl decreased 35% from an initial control of 33.7 to 21.5 ml/(min x mm Hg) in four subjects. Although this decrease was statistically significant, the values observed were not low enough to indicate that impaired diffusion was a prime cause of arterial unsaturation. Average Qc decreased 35% during acceleration from an initial control value of 12.9 to 8.2 liters/min, also a significant change. These values may have indicated that total pulmonary blood flow was reduced, but a more likely explanation is that a large portion of pulmonary flow perfused nonventilated regions. Dl and Qc returned toward initial control levels within 8 min after acceleration in most instances. lung volume during acceleration Submitted on March 1, 1965

Studies on the Pulmonary Diffusing Capacity by the Carbon Monoxide Breath Holding Technique: I. Normal Subjects

2009 ◽  
Vol 169 (5) ◽  
pp. 583-594 ◽  
Author(s):  
Haruo Kanagami ◽  
Toshiki Katsura ◽  
Koichiro Shiroishi ◽  
Kenji Baba ◽  
Toshiaki Ebina
Keyword(s):  
Carbon Monoxide ◽  
Normal Subjects ◽  
Breath Holding ◽  
Diffusing Capacity ◽  
Pulmonary Diffusing Capacity
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