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PubMed1996

BAL in children: a controlled study of differential cytology and cytokine expression profiles by alveolar cells in pediatric sarcoidosis.

STUDY OBJECTIVE: The development of BAL in children for both research and clinical purposes has been limited so far by the difficulty in establishing reference values. The aim of the study was (1) to define composition of BAL cellular components in control children and to evaluate the ability of these cells to express various cytokines, and (2) to study modifications of differential cytology and BAL cell cytokine responses in children with interstitial lung disorders. POPULATIONS AND METHODS: Two groups were investigated: a control group of 16 children who were concluded to be free of parenchymal lung disease after complete pulmonary investigation, and a group of 11 children with pulmonary sarcoidosis. Differential cytology was evaluated by standard techniques. BAL cell cytokine expression was studied at the level of messenger RNA (mRNA) by reverse transcription-polymerase chain reaction (RT-PCR) methods. RESULTS: In the control group, differential cell counts appeared to be similar to values reported in adult populations with normal distribution of the data and no influence of age. In this group, no transcripts for interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), IL-6, and transforming (correction of tranforming) growth factor-beta (TGF-beta) could be detected. In children with sarcoidosis, different profiles of IL-1beta, TNF-alpha, IL-6, and TGF-beta expression were individualized which seemed to be related to the activity and/or severity of the disease, IL-6 and TGF-beta mRNA being observed only in the more severe forms. CONCLUSION: These data provide information on BAL cell number and function in children. Characterization of BAL cytokine expression patterns during the course of interstitial lung diseases in children may be of great interest for evaluation of disease activity and/or severity and therefore for planning of therapy.

Actins↗
PubMed1975

Severe pleural restriction: the maximum static pulmonary recoil pressure as an acid in diagnosis.

Three patients with pleural restriction are presented in detail. One patient had had a right pneumonectomy and died of ventilatory failure due to left-sided restrictive pleurisy. The second patient had neoplastic pleural effusion and inactive tuberculosis. The third patient had systemic lupus erythematosus with bilateral restrictive pleuritis. The physiologic picture was similar in the three cases, with marked decrease of lung volumes, increase of the RV/TLC ratio, absence of airways obstruction, decrease of the Dco and decrease of dynamic lung compliance. In addition, each of these three patients and others with severe pleural restriction had a lower than normal maximum static pulmonary recoil pressure (Pmax). Since in pulmonary restrictive disease, the Pmax was found to be elevated, it was a useful test for distinguishing pulmonary restriction from pleural restriction.

Adenocarcinoma↗
PubMedDate not supplied

Lung transfer for carbon monoxide during the first three years of life.

Lung transfer for CO (TLCO) was measured in 35 healthy infants. A steady state, non-invasive method using a technique of alveolar sampling was employed [3]. During the first three years of life, TLCO expressed as mmol.min-1.kPa-1 increased linearly with height (cm): y = 0.036x - 1.15 (r = 0.91); with body weight (kg): y = 0.18x - 0.005 (r = 0.85); with body surface area (m2): y = 3.48x - 0.375 (r = 0.88); and with logn of age (months): y = 0.406x + 0.184 (r = 0.88). FRC was also measured in 29 of these infants by the helium dilution technique. FRC expressed in ml increased linearly with logn of age: y = 62.24x + 62.4 (r = 0.86) and was correlated with TLCO: y = 0.05x + 0.084 (r = 0.8). TLCO and FRC were correlated with the number of alveoli [7, 9]. Thus, in the first three years of life, lung volume and lung gas transfer seem to progressively adapt in order to satisfy energetic needs during growth.

Aging↗
PubMed2000

Cardiomegaly as a possible cause of lung dysfunction in patients with heart failure.

BACKGROUND: Our hypothesis is that an enlarged heart may compete for space with the lungs, causing a restrictive pattern that is often seen in patients with chronic heart failure. METHODS: Eighty patients with stable congestive heart failure in New York Heart Association classes II and III participated in the study. We measured cardiothoracic index (chest radiography), FEV1, vital capacity, alveolar volume, lung diffusion capacity for carbon monoxide (DLCO), and its 2 subcomponents alveolar-capillary membrane diffusion (DM), and pulmonary capillary blood volume. RESULTS: Reliable measurements were obtained in 72 of 80 participants enrolled. Cardiothoracic index averaged 57% +/- 7%. FEV1, vital capacity, alveolar volume, DLCO, and DM were inversely related to the cardiothoracic index (r = -0.514, -0.557, -0.522, -0.475, and -0.480, respectively). However, the relations of DLCO and DM with the cardiothoracic index were lost when DLCO and DM were adjusted for alveolar volume. A significant correlation (P < .01) was found between alveolar volume and vital capacity, FEV1, and DLCO (r = 0.799, 0.705, and 0.614, respectively). At multivariate analysis, cardiothoracic index, FEV1, and pulmonary capillary blood volume were independent predictors of DLCO, whereas alveolar volume, FEV1, and left ventricular ejection fraction were independent predictors of DM. CONCLUSIONS: Cardiac enlargement in chronic heart failure appears to be involved in causing restrictive lung pattern and a reduced alveolar volume that disturbs carbon monoxide diffusion.

Aged↗
PubMed1994

Pulmonary function thirteen to twenty-six years after repair of tetralogy of Fallot.

Lung function was evaluated in 68 patients 13 to 26 (median 19) years after repair of tetralogy of Fallot. Age at repair was 7 years (9 months to 42 years) and 51% had a palliative shunt. An outflow patch was inserted in 56%. Median vital capacity was 84% of predicted, forced expiratory volume in 1 second 83%, maximal voluntary ventilation at 40 breaths/min 70%, and diffusing capacity for carbon monoxide 77% of predicted. Scintigraphy demonstrated abnormal pulmonary perfusion in 86%. Average right lung perfusion was 57% (predicted 52%). Regional hypoperfusion could in some patients be explained by previous palliative shunt, pulmonary artery obstruction, or presence of aortopulmonary collaterals. Median symptom-limited work capacity was 82% (95% confidence limits 78% to 90%) of predicted. Twenty-eight physically active patients had high values for symptom-limited work capacity, vital capacity, forced expiratory volume in 1 second, and maximal voluntary ventilation at 40 breaths/min compared with those of inactive patients. Lung function variables were related to physical exercise and previous palliative shunt. Moderate or severe pulmonary valve incompetence had negative but not significant influence on lung function. There was no significant influence of acyanosis before repair, use of transannular patch, duration of follow-up, or smoking. We found moderately reduced work capacity and lung function late after repair of tetralogy of Fallot that did not cause symptoms. Lung function variables were high in young active male patients and low in patients with previous palliative shunt. A better lung function in active patients indicates that physical activity should be encouraged after repair of tetralogy of Fallot.

Adolescent↗
PubMedDate not supplied

The components of the carbon monoxide diffusing capacity in man dependent on alveolar volume.

The effect of alveolar volume (VA) on diffusing capacity for carbon monoxide (DL), membrane conductance (Dm) and pulmonary capillary blood volume (Qc) was investigated in 39 normal volunteers to study alveolar membrane expansion and capillary volume recruitment. DL/VA was related to alveolar volume breathing air and 95% oxygen respectively. Both relations appeared to be linear with a negative slope and were used to calculate Dm and Qc as a function of VA. The relation between Dm and VA resulted in: Dm = kVAx, where x characterizes the kind of membrane expansion with increasing alveolar volume, when we assume Dm = kA/delta. In this equation, A is the membrane area and delta the membrane thickness. In 36% of our subjects, x was nearly 0.67, which corresponds to an isotropic expansion of diffusion area with alveolar volume without changes in delta. In 41%, x was between 0.67 and 1. We hypothesized that, in these subjects, either some decrease of delta or some recruitment of alveoli was superimposed on the area increase according to x = 2/3. In recruitment, a proportional increase of diffusion area with alveolar volume is assumed, which means x = 1. Subjects over the age of 50 years (n = 12) showed greater variation in the value of x, which was greater than 1.3 in three and less than 0.6 in a further three. The relation between Qc and VA was best described by a second order polynomial, characterized by a maximum above 50% of VAmax. With lung expansion, either a recruitment of capillaries or a better contact between blood and air could occur up to that maximum. Where Qc was decreasing with further rise of VA, we assumed compression of capillaries by stretching of pulmonary tissue.

Adolescent↗
PubMed2002

The effect of renal transplantation on pulmonary function.

In patients with chronic renal failure, mechanical and hemodynamic changes could occur in the lungs without obvious pulmonary symptoms and findings and their effects could pave the way to pulmonary functional disorders. In this study, pulmonary functional disorders and especially alveolocapillary defects, which are frequently seen in uremia, were determined in renal transplanted patients. Pulmonary functions and diffusion capacity were assessed in uremic patients (n = 20) and in successfully transplanted patients (n = 20) without any lung disease or pulmonary edema symptoms and findings. Patients were selected randomly among outpatients who were followed up in a Nephrology and Transplantation Unit. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and peak expiratory flow (PEF25-75) were measured. Single breath carbon monoxide diffusion test and diffusion lung capacity adjusted for hemoglobin concentration (DLAdj) were done. The means of the spirometric values such as FVC, FEV1 and FEV1/FVC were normal in the nondialyzed uremic group, but the PEF25-75 value (68.7%) and diffusion capacity (DLAdj 72.7%) were found to be slightly low. There were 2 patients with normal values and 18 patients with some functional abnormalities in this nondialyzed uremic group. The means of all spirometric parameters and diffusion capacities were found to be normal in the transplanted group. There were 7 patients with normal function and 13 patients with some functional abnormalities in this transplanted group. When the nondialyzed uremic group and the transplanted group were compared statistically, significant differences were found between their spirometric values (except for FVC) and their diffusion capacities. Even though the uremic patients did not show any symptoms, their pulmonary function tests, especially diffusion capacity, were found to be disturbed. Although the transplanted patients as a group had normal mean spirometric values and diffusion capacity there were nevertheless many individual transplanted patients with defective diffusion capacity and abnormal spirometric values.

Adult↗
PubMed1995

[Measuring single breath diffusing capacity in a patient sample with healthy lungs--comparison with the European Coal and Steel Community standard values].

The measurement values of the diffusion parameters TLCO (diffusion capacity) and KCO (transfer coefficient) of 107 healthy subjects not suffering from pulmonary diseases were compared with the EC/European Community for Coal and Steel (ECCS) standard value formulas (2-5). The diffusion parameter KCO is markedly better described by the 1993 standard value formula than by the 1983 ECCS version. Men yield higher measured values than predicted by the 1993 EC formulas. The diffusion parameters of smokers are significantly lower than those of non-smokers.

Adolescent↗
PubMed1987

Effect of chronic airways obstruction on measurement of the single-breath carbon-monoxide-diffusing capacity.

We have examined the effect of chronic airways obstruction on the measurement of the single-breath carbon-monoxide-diffusing capacity (DLCLSB). We reviewed the results of 136 consecutive pulmonary function tests (comprising standard spirometry, helium dilution lung volumes and DLCOSB) obtained in patients who had an FEV1/FVC less than 70%. We calculated DLCOSB using two different values for alveolar volume (VA). In the first method (HeDL), VA was measured by single-breath dilution of helium during the test. In the second method (RbDL), VA was measured as the sum of the inspiratory vital capacity, performed during the test, and the residual volume, determined separately by helium rebreathing. The mean HeDL/RbDL, reflecting disparity between computations of DLCOSB in individual subjects was 0.85 +/- 0.13 in patients with moderate obstruction (40 less than or equal to FEV1/FVC% less than 60) and was 0.80 +/- 0.14 in those with severe obstruction (FEV1/FVC% less than 40). The mean HeDL/RbDL was lowest (0.73 +/- 0.12) in those with severe elevation of RV/TLC (RV/TLC% greater than 60). HeDL/RbDL correlated best with RV/TLC (r = -0.71, p less than 0.001). Unexplained variance in HeDL/RbDL was not significantly reduced by including the relationship between HeDL/RbDL and pulmonary function indices commonly used to measure airways resistance. These data suggest (1) the difference between HeDL and RbDL in patients with moderate and severe chronic airways obstruction is greater than previously reported; (2) the disparity between HeDL and RbDL stems from slow space ventilation rather than from increased resistance to air flow, and (3) HeDL underestimates gas transfer in poorly ventilated lung compartments.

Aged↗
PubMed1992

High-resolution CT diagnosis of emphysema in symptomatic patients with normal chest radiographs and isolated low diffusing capacity.

To determine the prevalence of "nonobstructive" (impairment of gas transfer) emphysema in a select population of smokers with dyspnea, a retrospective study of patients with emphysema evident at high-resolution computed tomography (HRCT) was undertaken. Four hundred seventy HRCT studies were reviewed. In 47 cases, centrilobular emphysema was the dominant or sole parenchymal abnormality. Concomitant chest radiographs were available in 41 of these cases; 16 of the 41 lacked radiographic findings of emphysema. Among these 16 patients, pulmonary function testing revealed 10 to have normal flow rates (ratio of forced expiratory volume in 1 second to forced vital capacity and forced expiratory volume in 1 second greater than 80% predicted) and impaired gas transfer (single-breath carbon monoxide diffusing capacity [DLCOSB] less than 80% predicted). With the exclusion of one patient with congestive heart failure from the group of 10, the severity of emphysema at HRCT correlated inversely with DLCOSB (r = -.643). These results indicate that HRCT allows detection of emphysema in symptomatic patients when chest radiographs and pulmonary function tests are nondiagnostic.

Female↗
PubMed2002

Differential changes of lung diffusing capacity and tissue volume in hypergravity.

In normal gravity, lung diffusing capacity (DL(CO)) and lung tissue volume (LTV; including pulmonary capillary blood volume) change in concert, for example, during shifts between upright and supine. Accordingly, DL(CO) and LTV might be expected to decrease together in sitting subjects in hypergravity due to peripheral pooling of blood and reduced central blood volume. Nine sitting subjects in a human centrifuge were exposed to one, two, and three times increased gravity in the head-to-feet direction (G(z+)) and rebreathed a gas containing trace amounts of acetylene and carbon monoxide. DL(CO) was 25.2 +/- 2.6, 20.0 +/- 2.1, and 16.7 +/- 1.7 ml. min(-1). mbar(-1) (means +/- SE) at 1, 2, and 3 G(z+), respectively (ANOVA P < 0.001). Corresponding values for LTV increased from 541 +/- 34 to 677 +/- 43, and 756 +/- 71 ml (P < 0.001) at 2 and 3 G(z+). Results are compatible with sequestration of blood in the dependent part of the pulmonary circulation just as in the systemic counterpart. DL(CO,) which under normoxic conditions is mainly determined by its membrane component, decreased despite an increased pulmonary capillary blood volume, most likely as a consequence of a less homogenous distribution of alveolar volume with respect to pulmonary capillary blood volume.

Adult↗