Diffusing capacity dependent on lung volume and age in normal subjects

1994 ◽  
Vol 76 (6) ◽  
pp. 2356-2363 ◽  
Author(s):  
H. Stam ◽  
V. Hrachovina ◽  
T. Stijnen ◽  
A. Versprille
Keyword(s):  
Reference Values ◽  
Linear Method ◽  
Hemoglobin Concentration ◽  
Normal Subjects ◽  
Random Coefficients ◽  
Diffusing Capacity ◽  
Alveolar Volume ◽  
Lung Volumes ◽  
Conversion Method ◽  
Older Subjects

In this study we determined reference values of total diffusing capacity of carbon monoxide (DLCO) and DLCO per liter alveolar volume (DLCO/VA) at total lung capacity (TLC) and at lung volumes below TLC in sitting position. In 55 healthy nonsmoking volunteers (20–85 yr old), we determined reference values at TLC level in which age was the only parameter. In a subgroup (n = 16) these references did not change by correction for normal variability in hemoglobin concentration. In all volunteers DLCO decreased and DLCO/VA increased with decreasing VA. The increase in DLCO/VA was linear and less in older subjects. We derived equations to calculate reference values of DLCO/VA for lung volumes at and below TLC with two methods: 1) “random coefficients linear” model, which calculates the reference values directly, and 2) a conversion method, which calculates DLCO/VA for lower VA levels from reference values at TLC. An advantage of the conversion method is the suitability of DLCO/VA reference values at TLC of other populations. A disadvantage is the greater standard deviation of these reference values compared with those obtained by the random coefficients linear method. DLCO can be found by multiplying DLCO/VA with VA.

The effect of conductive ventilation heterogeneity on diffusing capacity measurement

2008 ◽  
Vol 104 (4) ◽  
pp. 1094-1100 ◽  
Author(s):  
Sylvia Verbanck ◽  
Daniel Schuermans ◽  
Sophie Van Malderen ◽  
Walter Vincken ◽  
Bruce Thompson
Keyword(s):  
Carbon Monoxide ◽  
Vital Capacity ◽  
Experimental Situation ◽  
Normal Subjects ◽  
Diffusing Capacity ◽  
Capacity Measurement ◽  
Alveolar Volume ◽  
Estimation Errors ◽  
Single Breath ◽  
Ventilation Heterogeneity

It has long been assumed that the ventilation heterogeneity associated with lung disease could, in itself, affect the measurement of carbon monoxide transfer factor. The aim of this study was to investigate the potential estimation errors of carbon monoxide diffusing capacity (DlCO) measurement that are specifically due to conductive ventilation heterogeneity, i.e., due to a combination of ventilation heterogeneity and flow asynchrony between lung units larger than acini. We induced conductive airway ventilation heterogeneity in 35 never-smoker normal subjects by histamine provocation and related the resulting changes in conductive ventilation heterogeneity (derived from the multiple-breath washout test) to corresponding changes in diffusing capacity, alveolar volume, and inspired vital capacity (derived from the single-breath DlCO method). Average conductive ventilation heterogeneity doubled ( P < 0.001), whereas DlCO decreased by 6% ( P < 0.001), with no correlation between individual data ( P > 0.1). Average inspired vital capacity and alveolar volume both decreased significantly by, respectively, 6 and 3%, and the individual changes in alveolar volume and in conductive ventilation heterogeneity were correlated ( r = −0.46; P = 0.006). These findings can be brought in agreement with recent modeling work, where specific ventilation heterogeneity resulting from different distributions of either inspired volume or end-expiratory lung volume have been shown to affect DlCO estimation errors in opposite ways. Even in the presence of flow asynchrony, these errors appear to largely cancel out in our experimental situation of histamine-induced conductive ventilation heterogeneity. Finally, we also predicted which alternative combination of specific ventilation heterogeneity and flow asynchrony could affect DlCO estimate in a more substantial fashion in diseased lungs, irrespective of any diffusion-dependent effects.

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.

Diffusing capacity and blood flow in different regions of the lung

1962 ◽  
Vol 17 (4) ◽  
pp. 587-595 ◽  
Author(s):  
W. S. Spicer ◽  
R. L. Johnson ◽  
R. E. Forster
Keyword(s):  
Blood Flow ◽  
Normal Subjects ◽  
Breath Holding ◽  
Diffusing Capacity ◽  
Alveolar Volume ◽  
Obstructive Disease ◽  
Two Samples ◽  
Co Concentrations

We have measured the disappearance of CO and, in most instances, acetylene relative to helium from early and late portions of the expired alveolar gas after 1.5–20 sec of breath holding at rest in four normal subjects and seven patients with obstructive emphysema and three with sarcoidosis. In all individuals, except one patient with emphysema, graphs of the logarithm of the relative expired alveolar CO concentrations in early and late expired samples against time of breath holding were parallel, but those for the late expired samples lay below these for the early expired samples. The equality of the slopes of the two curves indicated that net diffusing capacity/alveolar volume for those regions of the lungs contributing to the two samples is similar even in severe obstructive disease. The displacement of the disappearance curves can be explained by errors in estimation of the time the gas spends in the alveoli and by an increased rate of CO disappearance caused by reduced alveolar volume during expiration. Submitted on December 18, 1961

Regional diffusing capacity in normal lungs during a slow exhalation

1982 ◽  
Vol 52 (6) ◽  
pp. 1487-1492 ◽  
Author(s):  
N. R. MacIntyre ◽  
J. A. Nadel
Keyword(s):  
Carbon Monoxide ◽  
Lung Volume ◽  
Vital Capacity ◽  
Normal Subjects ◽  
Lower Half ◽  
Diffusing Capacity ◽  
Lung Volumes ◽  
Lower Volume ◽  
Xenon 133 ◽  
Normal Lungs

From an analysis of carbon monoxide uptake and xenon-133 distribution after two bolus inhalations of these gases, we calculated regional diffusing capacity in the upper and lower volume halves of the lungs during the middle 60% of an exhaled vital capacity in five seated normal subjects. We found that the regional diffusing capacity of the upper half of the lungs was 11.6 +/- 4.2 (mean +/- SD) ml.min-1.Torr-1 and that the regional diffusing capacity of the lower half of the lungs was 24.4 +/- 2.4 ml.min-1.Torr-1 after 25% of the vital capacity had been exhaled. These values remained relatively constant as lung volume decreased from 25 to 75% of the exhaled vital capacity. Diffusing capacity in the upper half of the lungs ranged from 9.4 to 12.4 ml.min-1.Torr-1 during exhalation, and in the lower half of the lungs from 21.0 to 28.6 ml.min-1.Torr-1 during exhalation. These results suggest that total lung diffusing capacity remains relatively constant over this midrange of lung volumes and that this occurs because the regional diffusing capacities in both the upper and lower halves of the lungs remain relatively constant.

Effect of lung volume and positional changes on pulmonary diffusing capacity and its components

1991 ◽  
Vol 71 (4) ◽  
pp. 1477-1488 ◽  
Author(s):  
H. Stam ◽  
F. J. Kreuzer ◽  
A. Versprille
Keyword(s):  
Lung Volume ◽  
Supine Position ◽  
Body Position ◽  
Membrane Conductance ◽  
Normal Subjects ◽  
Negative Slope ◽  
Sitting Position ◽  
Diffusing Capacity ◽  
Alveolar Volume ◽  
Residual Capacity

Normal subjects have a larger diffusing capacity normalized per liter alveolar volume (DL/VA) in the supine than in the sitting position. Body position changes total lung diffusing capacity (DL), DL/VA, membrane conductance (Dm), and effective pulmonary capillary blood volume (Qc) as a function of alveolar volume (VA). These functions were studied in 37 healthy volunteers. DL/VA vs. VA yields a linear relationship in sitting as well as in supine position. Both have a negative slope but usually do not run parallel. In normal subjects up to 50 yr old DL/VA and DL increased significantly when subjects moved from a sitting to a supine posture at volumes between 50 and 100% of total lung capacity (TLC). In subjects greater than 50 yr old the responses of DL/VA and DL to change in body position were not significant at TLC. Functional residual capacity (FRC) decreases and DL/VA increases in all normal subjects when they change position from sitting to supine. When DL/VA increases more than predicted from the DL/VA vs. VA relationship in a sitting position, we may infer an increase in effective Qc in the supine position. In 56% of the volunteers, supine DL was smaller than sitting DL despite a higher DL/VA at FRC in the supine position because of the relatively larger decrease in FRC. When the positional response at TLC is studied, an estimation obtained accidentally at a volume lower than TLC may influence results. Above 80% of TLC, Dm decreased significantly from sitting to supine. Below this lung volume the decrease was not significant. The relationship between Qc and VA was best described by a second-order polynomial characterized by a maximum Qc at a VA greater than 60% of TLC. Qc was significantly higher in the supine position than in the sitting position, but the difference became smaller with increasing age. In observing the sitting and supine positions, we saw a decrease in maximum Qc normalized per square meter of body surface area with age.

Effects of gravity on lung diffusing capacity and cardiac output in prone and supine humans

2003 ◽  
Vol 95 (1) ◽  
pp. 3-10 ◽  
Author(s):  
M. Rohdin ◽  
J. Petersson ◽  
P. Sundblad ◽  
M. Mure ◽  
R. W. Glenny ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Normal Subjects ◽  
Arterial Oxygenation ◽  
Diffusing Capacity ◽  
Alveolar Volume ◽  
Pulmonary Capillary Blood Flow ◽  
Pulmonary Capillary ◽  
Supine Posture ◽  
Pulmonary Capillary Blood ◽  
Residual Capacity

Both in normal subjects exposed to hypergravity and in patients with acute respiratory distress syndrome, there are increased hydrostatic pressure gradients down the lung. Also, both conditions show an impaired arterial oxygenation, which is less severe in the prone than in the supine posture. The aim of this study was to use hypergravity to further investigate the mechanisms behind the differences in arterial oxygenation between the prone and the supine posture. Ten healthy subjects were studied in a human centrifuge while exposed to 1 and 5 times normal gravity (1 G, 5 G) in the anterioposterior (supine) and posterioanterior (prone) direction. They performed one rebreathing maneuver after ∼5 min at each G level and posture. Lung diffusing capacity decreased in hypergravity compared with 1 G (ANOVA, P = 0.002); it decreased by 46% in the supine posture compared with 25% in the prone ( P = 0.01 for supine vs. prone). At the same time, functional residual capacity decreased by 33 and 23%, respectively ( P < 0.001 for supine vs. prone), and cardiac output by 40 and 31% ( P = 0.007 for supine vs. prone), despite an increase in heart rate of 16 and 28% ( P < 0.001 for supine vs. prone), respectively. The finding of a more impaired diffusing capacity in the supine posture compared with the prone at 5 G supports our previous observations of more severe arterial hypoxemia in the supine posture during hypergravity. A reduced pulmonary-capillary blood flow and a reduced estimated alveolar volume can explain most of the reduction in diffusing capacity when supine.

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

1963 ◽  
Vol 41 (5) ◽  
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.

scholarly journals Diffusing capacity for nitric oxide: Reference values and dependence on alveolar volume

2007 ◽  
Vol 101 (7) ◽  
pp. 1579-1584 ◽  
Author(s):  
Ivo van der Lee ◽  
Pieter Zanen ◽  
Nadine Stigter ◽  
Jules M. van den Bosch ◽  
Jan-Willem J. Lammers
Keyword(s):  
Nitric Oxide ◽  
Reference Values ◽  
Diffusing Capacity ◽  
Alveolar Volume

scholarly journals Lung diffusing capacity for nitric oxide measured by two commercial devices: a randomised crossover comparison in healthy adults

2021 ◽  
pp. 00193-2021
Author(s):  
Thomas Radtke ◽  
Quintin de Groot ◽  
Sarah R. Haile ◽  
Marion Maggi ◽  
Connie C. W. Hsia ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Reference Values ◽  
Mixed Models ◽  
Fixed Effects ◽  
Healthy Adults ◽  
Test Interpretation ◽  
Diffusing Capacity ◽  
Alveolar Volume ◽  
Single Breath ◽  
Random Intercept

In Europe, two commercial devices are available to measure combined single-breath lung diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) in one maneuver. Reference values were derived by pooling datasets from both devices, but agreement between devices has not been established.We conducted a randomised crossover trial in 35 healthy adults (age 40.0±15.5 years, 51% female) to compare DLNO (primary endpoint) between MasterScreen™ (Vyaire Medical, USA) and HypAir (Medisoft, Belgium) devices during a single visit under controlled conditions. Linear mixed models were used adjusting for device and period as fixed effects and random intercept for each participant.Difference in DLNO between HypAir and MasterScreen was 24.0 mL·min−1·mmHg−1 (95% CI 21.7 to 26.3). There was no difference in DLCO (−0.03 mL·min−1·mmHg−1, 95% CI −0.57 to 0.12) between devices while alveolar volume (VA) was higher on HypAir compared to MasterScreen™ (0.48 L, 95% CI 0.45 to 0.52). Disparity in the estimation of VA and the rate of NO uptake (KNO=DLNO/VA) could explain the discrepancy in DLNO between devices. Disparity in the estimation of VA and the rate of CO uptake (KCO=DLCO/VA) per unit of VA offset each other resulting in negligible discrepancy in DLCO between devices. Differences in methods of expiratory gas sampling and sensor specifications between devices likely explain these observations.These findings have important implications for derivation of DLNO reference values and comparison of results across studies. Until this issue is resolved reference values, established on the respective devices, should be used for test interpretation.

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