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PubMed1987

[Functional significance of lung siderosis in electrode welders].

56 electric arc welders found in a cross-sectional study to show pulmonary siderosis in full size x-rays were clinically examined. Looking for the discussed functional, relevance of such lung diseases in welders the diagnostic program included spirometry, flow-volume-curves, body-plethysmography, single breath diffusion capacity, pulmonary compliance and ergooxytensiometry. The results are supporting that "lung siderosis" in welders is associated with slight functional deterioration in the type of interstitial lung diseases.

Electrodes↗
PubMed1990

A follow-up study of pulmonary function in patients with primary Sjögren's syndrome.

Twenty-seven patients (25 women, 2 men) with primary Sjögren's syndrome, previously reported to have reduced pulmonary diffusing capacities were reexamined in a 7-year follow-up in order to evaluate longitudinal alterations in pulmonary function. Primary Sjögren's syndrome was diagnosed according to the Copenhagen criteria. The present examination revealed normal and unchanged values for vital capacity, forced expiratory volume in 1 s, maximal expiratory flow at 50% of expired vital capacity (MEF50), and diffusing capacity per liter alveolar volume. Total diffusing capacity (P less than 0.01) and MEF75 (P less than 0.05), were, however, significantly reduced compared with the predicted values, indicating pulmonary involvement primarily affecting the small airways. The longitudinal examination, furthermore, showed increasing values for total diffusing capacity (P less than 0.02), diffusing capacity per liter alveolar volume (P less than 0.001), and MEF75 (P less than 0.02), suggesting an improvement in lung status in the course of time. No correlation was found between MEF75 and diffusing capacities, nor between alterations in pulmonary function and complaints of dyspnoea, tiredness, cough, expectoration, tobacco smoking, or medical treatment with bromhexine, glucocorticosteroids, essential fatty acids, or nonsteroid antiinflammatory drugs.

Adult↗
PubMed1991

Lung diffusing capacity and red blood cell volume.

The aim of this study was to test whether a large surface to volume ratio of the red blood cells is advantageous for O2 transfer in lungs. Suspensions of washed large (human) and small (sheep) red blood cells were used to perfuse in random order isolated cat lungs (n = 7). The lungs were kept at 27 degrees C, ventilated with 1.0 l/min and perfused with 110 ml/min. Hemoglobin concentration was 70 g/l. Assuming an inhomogeneous lung with an alveolar dead space compartment, pulmonary diffusing capacity for O2 (DLO2) was 0.53 +/- 0.10 ml.min-1.mmHg-1 (mean +/- SD) when perfusing with sheep red cells and 0.52 +/- 0.13 with human red cells. On the basis of a lung model with a low VA/Q and a high VA/Q compartment the values were 0.86 and 0.93. Thus, DLO2 was not larger with smaller red blood cells, i.e. with higher red cell surface area per blood volume. Possible explanations for this unexpected result are discussed.

Animals↗
PubMed2001

Pulmonary function in non-insulin-dependent diabetes mellitus.

BACKGROUND: In type I diabetes mellitus, lung function has been investigated in several clinical studies, but there are few data concerning pulmonary function abnormalities in patients with non-insulin-dependent diabetes mellitus (NIDDM). OBJECTIVES: The aim of this study was to assess the presence of pulmonary function abnormalities in patients with NIDDM and to verify the possible associations between diabetic renal microangiopathy, retinopathy and diabetes control. METHOD AND PATIENTS: Thirty patients with NIDDM were collected and divided into two similar groups: subjects with retinopathy and/or diabetic glomerulopathy (group 1, n = 15) and patients without any complications (group 2, n = 15). 17 were males and 13 females, aged from 45 to 81 years. They had had diabetes for 3-23 years and were studied at the Division of Internal Medicine, with an outpatient service for diabetic patients. All patients were non-smokers. The presence of diabetic glomerulopathy was determined by measuring the 24-hour protein excretion rate using the nephelometric method. The presence of retinopathy was determined by using ophthalmoscopy. Glycosylated hemoglobin was measured as an indicator of glycemic control. We performed a global spirometry and measured pulmonary diffusion capacity by the single-breath method corrected by alveolar volume. RESULTS: We found a significant reduction in lung diffusion capacity for carbon monoxide (DL(CO)) in the group of patients with other signs of diabetic microangiopathy (p < 0.005) and a significative correlation between DL(CO )and the grade of albuminuria (r = -0.83, p < 0.001). CONCLUSIONS: Pulmonary function abnormalities, in particular a reduction in diffusion capacity, are common in patients with NIDDM and signs of diabetic microangiopathy. A possible explanation is related to an impaired pulmonary microvasculature and alveolar epithelial basal lamina.

Aged↗
PubMed2002

Chronic and acute effects of "crack" cocaine on diffusing capacity, membrane diffusion, and pulmonary capillary blood volume in the lung.

STUDY OBJECTIVES: To evaluate possible alterations in the diffusing capacity of the lung for carbon monoxide (DLCO) or its components, membrane diffusing capacity of the lung for carbon monoxide (DMCO) and pulmonary capillary blood volume (Vc), in habitual smokers of "crack" cocaine (with or without tobacco) and following the short-term administration of inhaled cocaine base or IV cocaine HCl. DESIGN: Cross-sectional and longitudinal evaluation of DLCO and its components in smokers of cocaine alone, tobacco alone, and cocaine plus tobacco, and in nonsmokers and ex-smokers. Measurement of possible acute effects on DLCO and its components after experimental short-term administration of IV and smoked cocaine. SETTING: University and Veterans Affairs hospital research laboratories. PARTICIPANTS: Convenience sample of habitual smokers of crack cocaine with or without tobacco and matched control nonsmokers and ex-smokers, and smokers of tobacco only. MEASUREMENTS: DLCO, DMCO, and Vc. CONCLUSIONS: Neither habitual cocaine smoking in cross-sectional or longitudinal analysis nor the short-term administration of inhaled alkaloidal cocaine significantly affected DLCO or its component parts. In contrast, a clear cross-sectional effect of regular tobacco smoking was demonstrated.

Adult↗
PubMedDate not supplied

Morphometry of the human lung: the state of the art after two decades.

This paper reviews the development of the methods for estimating morphometric parameters describing the human lung. The original work was done by light microscopy, but physiologically relevant data depend on studying the delicate structure of alveoli and capillaries by electron microscopy. Methodological improvements of recent years permitted this approach. This yielded estimates of alveolar surface which are by 80% larger than the original data; the reasons are explained by the gain in resolution. On the basis of these data, and by accounting for additional experimental information on the functional availability of gas exchanging surfaces, estimates of pulmonary diffusing capacity (DL) in the range of 90--190 ml O2 . min-1 . mmHg-1 are obtained, which compare reasonably well with physiological estimates of DL obtained under conditions of work.

Capillaries↗
PubMed1984

Pulmonary function in hemophiliac patients treated with commercial factor VIII concentrates.

Pulmonary function was tested before and after the administration of a commercial preparation of factor VIII concentrate in 20 patients with hemophilia A. The material was infused through the filter provided by the manufacturer, which is supposed to remove particles larger than 170 mu. Baseline information showed that patients who smoke had a lower pulmonary diffusing capacity for carbon monoxide than nonsmokers (22.9 +/- 4.2 ml/minute/mm Hg, p less than 0.01). The administration of factor VIII was not associated with clinical abnormalities. There was a small reduction in carbon monoxide diffusing capacity (27 +/- 5.8 to 26.2 +/- 5.9 ml/minute/mm Hg, p = 0.03), which was no longer significant after carbon monoxide diffusing capacity was corrected for lung volume (5.66 +/- 1.32 to 5.54 +/- 1.34, p greater than 0.06). This study does not support the need for 40 mu filtration of factor VIII concentrate.

Adolescent↗
PubMed1976

Pulmonary gas exchange in dogs ventilated with mixtures of oxygen with various inert gases.

To study the influence of physical properties of the respired gas on alveolar gas exchange, alveolar-arterial partial pressure differences for O2 and CO2 were measured in anesthetized dogs that were artificially ventilated with gas mixtures of O2 in N2, He, Ar or SF6. In both hyposia and normoxia alveolar-arterial PO2 differences had the tendency to increase slightly in the sequence of the respired inert gases SF6 less than Ar less than N2 less than He, while arterial-alveolar PCO2 differences remained practically unchanged. Pulmonary diffusing capacity for CO(DCO), determined by the single breath technique, revealed no significant differences between the four gas mixtures used. The possible mechanisms underlying these results are discussed in connection with the physical properties of the respired gas mixtures.

Animals↗
PubMed1982

Pulmonary function in patients with rheumatoid arthritis.

106 women and 38 men suffering from definite or classical rheumatoid arthritis underwent a pulmonary function test. The results were correlated to the duration and various clinical activity parameters of the disease. Pulmonary diffusion capacity was found to be reduced compared with the predicted values (p less than 0.05), irrespective of the duration or activity of the disease. The findings suggest that inflammatory vascular changes in the lungs usually occur in rheumatoid arthritis even in cases where other extraarticular manifestations can usually not be demonstrated.

Adolescent↗
PubMed1982

[Changes in some ventilation and respiration parameters in patients with chronic obstructive lung disease in prospective longitudinal study].

The changes of several parameters of ventilation and respiration in 104 men taken into prospective longitudinal observation were analysed. All men in average 53.3 years old at the time of first examination were suffering from chronic obstructive lung diseases. The time between last and first examination amounted to 52 months in average. During this period the functional state did not change in one third of all patients; in the other two thirds the condition has impaired and 19 (18.3%) among 104 had died. The functional parameters evaluated showed a statistically significant decrease of FEV1 (71 ml in average every year) and of pulmonary diffusion capacity for CO by the steady state and single breath methods whereas the changes of airway resistance being insignificant in these cases. The results give rise to the statement that progression of the disease would occur in the area of peripheral airways and alveoli.

Adult↗
PubMed1994

Inverse relation between plasma concentration of von Willebrand factor and CrEDTA clearance in systemic sclerosis.

OBJECTIVE: Microvascular abnormalities involving endothelial cell dysfunction occur as an early event in systemic sclerosis. We studied plasma concentrations of von Willebrand factor (vWf), a substance released from injured endothelial cells, and its relation to pulmonary and renal dysfunction. METHODS: vWf was determined by immunoelectrophoresis. Renal function was assessed by CrEDTA clearance, an accurate measure of glomerular filtration rate and pulmonary function by spirometry and carbon monoxide diffusing capacity. Pulmonary pressure was measured by Doppler cardiography. RESULTS: In 22 patients with scleroderma, vWf concentrations related inversely to CrEDTA clearance. In contrast, no relationship between plasma vWf and pulmonary function was found; 9/10 patients with pulmonary hypertension and 9/12 patients with normal pulmonary pressure showed elevated levels of vWf. However in 5 patients with pulmonary hypertension without radiographic evidence of pulmonary fibrosis there was a strong correlation between plasma vWf and pulmonary pressure (rho = 0.90) which fell short of statistical significance due most likely to small population size. CONCLUSION: Renal but not pulmonary dysfunction was associated with elevated plasma levels of vWf.

Adult↗
PubMed1977

Nitrofurantoin-induced alterations in pulmonary tissue. A report on five patients with acute or subacute reactions.

Three patients with acute and two with subacute nitrofarantoin-induced pulmonary reactions were studied clinically and by examinining microcoscopically needle biopsy specimens of their lungs. In all five patients slight vasculitis and a few interstitial eosinophils were found in the pulmonary tissue 1-2 weeks after the withdrawal of nitrofurantion therapy. Alveolitis, fibrinous alveolar exudate and perivascular granulomas were also seen in some specimens. The patients with acute reactions had marked blood eosinophilia. In all patients, pulmonary diffusing capacity (DLCO) was below normal, but ventilatory function was not appreciably affected. Withdrawal of nitrofurantion resulted in complete or partial improvement in 4-8 weeks. Our clinical and histological findings support the suggestion that a type III immune-complex-mediated reactions is involved in acute and subacute hypersensitivity reactions to nitrofurantoin.

Adult↗
PubMed1987

The postnatal development and growth of the human lung. I. Morphometry.

The lungs of 7 children (age: 26 days to 5 years 4 months) who died from non-respiratory causes were morphometrically investigated by means of light and electron microscopy. For analysis, the set of data was supplemented with results obtained previously on 8 normal adult lungs using similar quantitative techniques (Gehr et al., 1978). The results allowed us to distinguish two phases of postnatal lung development and growth, the first phase lasting from birth to about 18 months and the second phase from then to adulthood. The first phase was characterized by an overproportionate volume increase in the O2-transporting media, air and blood, at the expense of the parenchymal tissue compartment. In the second phase, the volumetric composition of the lung did not change further because there was proportionate growth of all lung compartments. The growth curves for the airspace and capillary surface areas were not biphasic: they increased in direct proportion to lung volume from birth to adulthood, indicating a steady increase in the air-blood interface complexity during the entire growth period. As a consequence of the differences in growth paces between the various structural lung components in early childhood, the morphometric parameters showed large variations in their overall growth rates between birth and adulthood. Thus, the parenchymal tissue components increased by a factor of 15, lung volume and the gas-exchange surface areas between 20 and 25 times (in parallel to body mass), and, finally, the O2-transporting media, air and blood, more than 30 times. The morphometrically determined pulmonary diffusing capacity for O2 (DLO2) scaled with body mass to the power of 1.15, a value significantly different from 1. This relative improvement with age of the gas exchange function per unit body mass is due mainly to an overproportionate growth of the capillary blood compartment.

Adult↗
PubMed1983

[Alveolaro-capillary gas exchange. Considerations on the evaluation of carbon monoxide diffusion].

This study is based on 107 male individuals aged between 20 and 73 years, all of them exempt from any disease. They were submitted to instrument examination for measuring the CO pulmonary diffusing capacity with the single breath method. The data so obtained were then statistically elaborated considering the index value of CO transfer, the Helium partition (RHe) and the CO partition and diffusion (R&DCO). The CO transfer index has shown a particularly extensive range; if we take as normality level-20%, a consistent ratio of individuals (20,56%) falls in a range of deficitary pulmonary diffusion though in absence of aèny clinical evidence of pathology. The subsequent statistical elaboration of the data after logarithmic transformation, by the means of the linear regression model, has allowed to reduce the variance of the R&D CO index improving his classificative capability.

Adult↗
PubMed1981

Competitive inhibition of carbon monoxide transport: evidence against a carrier.

The existence of a saturable carbon monoxide (CO) carrier in the lung remains controversial. The carrier hypothesis was invoked to explain data that indicated that pulmonary diffusing capacity for CO (DLCO) decreases with increasing CO concentration. To test this hypothesis, we measured DLCO in 14 normal adult subjects at three alveolar CO concentrations (60, 660, and 2,060 ppm). Each mixture contained a constant amount of labeled C18O (60 ppm) and a balance of unlabeled C16O. If a saturable carrier exists at increasing CO concentrations, the unlabeled CO would compete for most of the sites on the carrier molecule, effectively inhibiting the uptake of the labeled C18O. C18O diffusing capacities (mean +/- SD) for the three levels of CO were 34.9 +/- 5.6, 33.0 +/- 6.0, and 34.7 +/- 7.8. There were no significant differences (P greater than 0.2) among the three levels. In another group of subjects we repeated the study using a gas mixture containing 130 ppm C18O. No significant differences were found. As a result, we find no evidence to support a CO carrier hypothesis.

Adolescent↗
PubMed1978

Adaptation of the growing lung to increased Vo2: III. The effect of exposure to cold environment in rats.

This study was undertaken to further test the hypothesis that increased Vo2 operates as a stimulus for enhanced lung growth leading to a pulmonary diffusing capacity adapted to the body's O2 requirements. Vo2 was augmented by raising 4-week-old rats for 3 weeks at 11 degrees C ambient temperature, with controls kept at 24 degrees C; this led to an increase in Vo2 averaged over 24 h by 64%. In contrast to previous experiments with waltzing mice this regime did not affect body growth, as the final body weights were identical in both groups. In the cold-exposed rats the lung volume was larger by 24%, due to an increase by 26% in air volume (at about TLC), 13% in capillary blood volume and 19% in tissue volume. The alveolar and capillary surface areas were increased by 18%, and Dm and Dl by 17% and 21% respectively. It is concluded that the hypothesis of adaptation of pulmonary gas exchange capacity to increased Vo2 cannot be rejected. Whilst in previous experiments some doubts had to be retained as to the specificity of the stimulus, because of its rather marked effect on body weight, this reservation does not hold in this case. The structural modifications which lead to increased Dl in the various experimental models are discussed.

Adaptation, Physiological↗
PubMed1982

Morphometrics of the avian lung. 2. The wild mallard (Anas platyrhynchos) and graylag goose (Anser anser).

The lungs of 5 wild mallard ducks (Anas platyrhynchos) and 5 feral graylag geese (Anser anser) of mean body weight 1.04 and 3.84 kg, respectively, were fixed in situ by intratracheal infusion of 2.3% glutaraldehyde, pH 7.4 and total osmolarity 350 mOsm, at a pressure head of 25 cm, and analysed by standard morphometric techniques. The following data apply to both lungs together, in the fixed state, the first value relating to Anas and the second to Anser in each case: lung volume, 30.4 and 95.3 cm3; volume of exchange tissue, 12.32 and 38.50 cm3; volume of capillary blood, 4.06 and 12.49 cm3; surface area of blood-gas (tissue) barrier per unit body weight, 28.56 and 23.10 cm2/g; surface area of the blood-gas (tissue) barrier per unit volume of lung, 977 and 932 cm2/cm3; surface area of blood-gas (tissue) barrier per unit volume of exchange tissue, 241 and 230 mm2/mm3; harmonic mean thickness of tissue barrier, 0.133 and 0.118 microns; arithmetic mean thickness of tissue barrier, 0.903 and 0.887 microns; harmonic mean thickness of plasma layer, 0.369 and 0.322 microns; mean total morphometric pulmonary diffusing capacity per unit body weight, 3.85 and 3.59 ml O2/min/mm Hg/kg. These morphometric parameters of Anas and Anser are compared with those reported in the literature for the domestic fowl (Gallus gallus), the budgerigar (Melopsittacus undulatus), the house sparrow (Passer domesticus), and the violet-eared hummingbird (Colibri coruscans). The lungs of these six avian species show progressively advancing adaptations, from Gallus, through Anser, Anas, Melopsittacus and Passer, to Colibri, which appear to be consistent with the energetic characteristics of these birds.

Animals↗