[The feasibility of measuring the total lung capacity and residual volume by the radiographic method].
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Adult↗
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Results for “Pulmonary Diffusing Capacity”
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Carbon monoxide diffusing capacity, other indices of lung function, and respiratory symptoms in a general population sample.
To assess the relationships among single-breath diffusing capacity for CO (DLCOsb) (13), respiratory symptoms, and cigarette smoking in a general population sample, the data of 718 men and 894 women 20 yr of age or older were analyzed, and comparisons were performed with flow-volume curve (MEFV) variables and the slope of the alveolar plateau (DN2%/L) as well. Percent predicted DLCOsb and its correction for alveolar volume (DL/VA) were significantly lower in smokers than in nonsmokers. The relationship of presence/absence of respiratory symptoms and cigarette smoking with DLCOsb and DL/VA was significant. DLCO indices were almost always selected as discriminant variables in multivariate analysis between asymptomatic and symptomatic subjects. Poor concordance among lung function tests was evident: in men, 30% with abnormal (i.e., lower than 97.5% percentile) and 21% with normal DLCO indices also had abnormal MEFV parameters and/or DN2%/L. In women, the corresponding figures were 24 and 10%, respectively. In men, when considering only DLCO indices, the percentage of symptomatic subjects with abnormal lung function tests ranged from 33% in those with at least one symptom to 45% in those complaining of dyspnea. When the proportion of symptomatic subjects with DN2%/L and MEFV abnormalities were added, it increased to 56 and 66%, respectively. However, in women the proportion of symptomatic subjects with abnormal lung function indices was very small. These results indicate the usefulness of including CO diffusing capacity in epidemiologic surveys in the detection of abnormalities.
Adolescent↗
Pathophysiologic correlations in lymphoid interstitial pneumonia.
Effective alveolar volume, diffusing capacity for carbon monoxide (DCOsb), volume-corrected diffusing capacity (D/VA), static lung compliance (Cst), and lung distensibility were measured in 16 sheep seropositive for maedi-visna virus (MVV) immediately before they were killed. Lungs were inflation-fixed, and the left lung was randomly sampled for morphometric analysis. The total lung weight, total fixed lung volume, volume densities of tissue (Vvt) and air (Vva), and the alveolar surface density were measured and correlated with the physiologic measurements. The density of surface forces could not account for the variation in the distensibility of the lungs, indicating that tissue-related forces may be important in determining lung distensibility in lymphoid interstitial pneumonia (LIP) associated with MVV infection. Possible sources of tissue-related forces are the contractile tissue associated with lung parenchyma, airways, or vasculature. When DCOsb was corrected for volume, a strong negative correlation with Vvt was noted, indicating that factors distinct from lung-volume reduction are important in limiting gas exchange in LIP associated with MVV infection. More sheep demonstrated abnormal D/VA values than any other physiologic measurement, with reduced values being apparent even in sheep considered clinically normal and with little or no morphometric evidence of lung disease. Measurements of diffusing capacity are thus considered the most sensitive functional index of disease progression.
Animals↗
Exercise tolerance in patients with mitral stenosis before and after acute percutaneous mitral valvuloplasty. Role of lung diffusing capacity limitation?
The aim of this study was to specify in patients with tight mitral stenosis whether lung diffusing capacity could play a role in their exercise intolerance. A similar study was recently carried out in patients with moderate chronic heart failure. Ten patients with tight mitral stenosis were studied before and 6 months after successful percutaneous transvenous balloon valvuloplasty and compared to six control subjects. Measurements of diffusing capacity, evaluated by the lung transfer factor (TLCO) and by the transfer coefficient (TLCO/VA), obtained at rest and during early recovery after cardiopulmonary exercise testing were performed. Cardiac output was determined non-invasively, both at rest and during exercise, using the carbon dioxide exponential rebreathing technique. Prior to valvuloplasty, TLCO and TLCO/VA were not different at rest between the two groups. During exercise, patients differed from control subjects, with lower oxygen uptake (P < 0.001) and lower cardiac output at peak exercise (P < 0.001). These values at peak exercise were significantly correlated (P = 0.02; r = 0.75). Moreover, patients differed from control subjects at early recovery after peak exercise with an absence of increase in TLCO (P < 0.05). Six months after valvuloplasty, a decrease of both TLCO (P < 0.01) and TLCO/VA (P < 0.05) was observed at rest. During exercise, comparison of patients demonstrated a significant increase of both peak exercise oxygen uptake (SLVO2, P < 0.01) and cardiac output (P < 0.001). At early recovery after peak exercise there was a significant increase in TLCO (P < 0.05) and TLCO/VA (P < 0.01), such that a delta TLCO and a delta TLCO/VA appeared (P < 0.05) identical to that observed in control subjects. Moreover, delta SLVO2 was significantly correlated in patients with delta Q+ delta TLCO/VA (P = 0.02; r = 0.72). In conclusion, this study suggests a role, at least partial, of lung diffusing capacity in exercise intolerance in patients with tight mitral stenosis and in the improvement of their aerobic exercise capacity demonstrated after successful percutaneous balloon valvuloplasty.
Adult↗
Prognostic value of bronchoalveolar lavage lymphocyte count in recently diagnosed pulmonary sarcoidosis.
We prospectively looked at the prognostic value of bronchoalveolar lavage (BAL) lymphocyte count in 98 patients with recently diagnosed (less than 4 months) untreated sarcoidosis. These 50 men and 48 women (mean age, 37.4) were followed up for a period of 6 to 60 months (mean, 25.6), and were clinically evaluated every three to six months with repeated chest roentgenograms and pulmonary function tests. Twenty-four patients required steroid treatment during the study period. The proportion of treated patients was not significantly higher in the group presenting a BAL lymphocyte count less than or equal to 30 percent at diagnosis than in the group with fewer lymphocytes (31.9 and 17.7 percent of total group respectively, p = 0.10). No significant change in TLC, FRC, FVC, FEV1 or DLCO was found at follow-up between the groups with or without an initial high lymphocyte count. In the treated group, BAL lymphocyte percent weakly correlated with the improvement of FEV1 and FVC while on steroid treatment (mean duration: 3.5 months): r = 0.41, p = 0.031 and r = 0.36, p = 0.05 respectively; no correlation was found with lung volumes and DCO. We conclude that BAL lymphocyte count at the time of diagnosis is not a helpful predictor of lung function deterioration in recently diagnosed sarcoidosis and is not very useful in predicting response to treatment.
Adult↗
Cyclophosphamide is associated with pulmonary function and survival benefit in patients with scleroderma and alveolitis.
BACKGROUND: Lung inflammation (alveolitis) may cause lung fibrosis in scleroderma. OBJECTIVE: To determine whether cyclophosphamide treatment is associated with retention of lung function and improved survival in scleroderma patients with alveolitis. DESIGN: Retrospective cohort study. SETTING: Johns Hopkins and University of Maryland Scleroderma Center. PATIENTS: 103 patients with scleroderma who had bronchoalveolar lavage or lung biopsy. INTERVENTION: Cyclophosphamide therapy. MEASUREMENTS: 1) Serial measurement of forced vital capacity (FVC) and carbon monoxide diffusing capacity and 2) survival. RESULTS: During a median follow-up of 13 months after bronchoalveolar lavage or biopsy, patients with alveolitis who did not receive cyclophosphamide therapy experienced a decrease in FVC (mean difference, -0.28 L [95% Cl, -0.41 to -0.16 L] and -7.1% of the predicted value [Cl, -10.9% to -4.0%]). Carbon monoxide diffusing capacity also decreased in these patients (mean difference, -3.3 x mmol min(-1) x kPa(-1) [Cl, -4.6 to -2.1 mmol x min(-1) x kPa(-1)] and -9.6% of the predicted value [Cl, -16.7% to -2.4%]). During a median follow-up of 16 months, patients with alveolitis who received cyclophosphamide were more likely to have a good outcome (stabilization or improvement) in FVC (relative risk, 2.5 [Cl, 1.5 to 4.1]) and diffusing capacity (relative risk, 1.5 [Cl, 1.0 to 2.2]). These patients also had improved survival; the median survival rate was 89% (25th, 75th percentiles, 84%, 94%) compared with 71% (25th, 75th percentiles, 55%, 86%) in untreated patients (P = 0.01, log-rank test). CONCLUSIONS: The presence of lung inflammation identifies patients with scleroderma who are more likely to have worsening lung function. Lung function outcomes and survival are improved in patients with alveolitis who receive cyclophosphamide.
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Higher prevalence of obstructive airway disease in patients with thoracic or abdominal aortic aneurysm.
BACKGROUND AND AIM: The risk factors of aortic aneurysm (AA) are comparable with those described for chronic obstructive pulmonary disease. This study was performed to determine whether patients with AA have a higher than average prevalence of obstructive airway disease. METHODS: We performed pulmonary function tests in 240 consecutive patients (182 men and 58 women; age, 70 +/- 10 years) with thoracic or abdominal AA. The results were compared with those in individuals without obvious cardiovascular disease (control) and in patients with coronary artery disease who were matched for age, gender, smoking status, and other atherosclerotic risk factors. RESULTS: Patients in the AA group had a lower forced expiratory volume in 1 second/forced vital capacity (%) and carbon monoxide diffusing capacity (%/predicted value) than did the control group (P <.01). The proportion of patients with airway obstruction, defined as forced expiratory volume in 1 second/forced vital capacity of 70% or less, was higher in the AA group (100/240; 42%) than in the control (51/223; 23%) and coronary artery disease (43/238; 18%) groups. Multiple logistic regression analysis results revealed that the presence of an AA and male gender were associated with a higher risk of airway obstruction (odds ratio, 2.928; 95% CI, 1.722 to 4.979; and odds ratio, 1.622; 95% CI, 1.055 to 2.493, respectively). CONCLUSION: These data suggest that AA may be a risk factor indicative of the presence of chronic obstructive pulmonary disease. A higher prevalence of depressed pulmonary function should be suspected as a preoperative risk in presence of thoracic or abdominal AA as compared with other types of cardiovascular disorders.
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Pretransplant pulmonary function tests predict risk of mortality following fractionated total body irradiation and allogeneic peripheral blood stem cell transplant.
PURPOSE: To determine the value of pulmonary function tests (PFTs) done before peripheral blood stem cell transplant (PBSCT) in predicting mortality after total body irradiation (TBI) performed with or without dose reduction to the lung. METHODS AND MATERIALS: From 1997 to 2004, 146 consecutive patients with hematologic malignancies received fractionated TBI before PBSCT. With regimen A (n=85), patients were treated without lung dose reduction to 13.6 gray (Gy). In regimen B (n=35), total body dose was decreased to 12 Gy (1.5 Gy twice per day for 4 days) and lung dose was limited to 9 Gy by use of lung shielding. In regimen C (n=26), lung dose was reduced to 6 Gy. All patients received PFTs before treatment, 90 days after treatment, and annually. RESULTS: Median follow-up was 44 months (range, 12-90 months). Sixty-one patients had combined ventilation/diffusion capacity deficits defined as both a forced expiratory volume in the first second (FEV1) and a diffusion capacity of carbon dioxide (DLCO)<100% predicted. In this group, there was a 20% improvement in one-year overall survival with lung dose reduction (70 vs. 50%, log-rank test p=0.042). CONCLUSION: Among those with combined ventilation/diffusion capacity deficits, lung dose reduction during TBI significantly improved survival.
Adult↗
[Diffusion capacity of the hematoparenchymal barrier for oxygen in the breathing of helium-oxygen gas mixtures].
In 25 rabbits with local anesthesia, recordings of partial oxygen pressure in the hindlimb arterial and venous blood, oxygen tension in muscles and some other parameters followed by calculation of the muscle hematoparenchymatous barrier, revealed that, in inhalation of normoxic helio--oxygen mixture, the hematoparenchymatous barrier's diffusion capacity for oxygen increases as compared with the analogous value in breathing with air. In inhalation of hypoxic helio--oxygen and nitrogen--oxygen mixtures (11% O2), the barrier's diffusion capacity for oxygen proves higher than in breathing with respective normoxic gas mixtures. A possible pharmacological effect of helium influence upon plasmatic membranes of the hematoparenchymatous barrier's components is discussed.
Animals↗
A prospective study of pulmonary function in patients treated with paclitaxel and carboplatin.
BACKGROUND: Adverse effects of paclitaxel and carboplatin have been well described; however, pulmonary toxicity after patients receive this regimen has not been investigated extensively. METHODS: To clarify this issue, 33 consecutive patients who were treated with paclitaxel and carboplatin underwent prospective evaluation of respiratory function, which included pulmonary symptoms, pulmonary function tests (PFTs), arterial blood gas levels, and radiographic studies. Assessment was performed before and after completion of chemotherapy in all patients. Patients with substantial declines in PFTs, defined as a decline > or = 20 percent in forced expiratory volume in 1 second (FEV1), total lung capacity (TLC), or diffusion capacity for carbon monoxide (DLCO), were reassessed 5 months later. RESULTS: After chemotherapy, there were no significant changes in forced vital capacity (FVC; 111%+/-21% of the predicted value before chemotherapy vs. 111+/-20% of the predicted value after chemotherapy), FEV1 (108%+/-24% of the predicted value before chemotherapy vs. 107%+/-22% of the predicted value after chemotherapy), FEV1/FVC ratio (79%+/-8% before chemotherapy vs. 78%+/-6% after chemotherapy), alveolar volume (VA; 95%+/-14% of the predicted value before chemotherapy vs. 96%+/-14% of the predicted value after chemotherapy), or TLC (96%+/-14% of the predicted value before chemotherapy vs. 97%+/-13% of the predicted value after chemotherapy). In contrast, there was a significant decline in DLCO (101%+/-20% of the predicted value before chemotherapy vs. 96+/-21% of the predicted value after chemotherapy; P < 0.05). Arterial blood gas levels did not change after treatment. No patient had decreased FEV1 or TLC levels by > or = 20%, whereas 4 of 33 patients (12%) exhibited a substantial decline (> or = 20%) in DLCO that persisted 5 months after treatment (DLCO at baseline, immediately after chemotherapy, and 5 months after the completion of chemotherapy, respectively: 99%+/-36% of the predicted value vs. 75%+/-28% of the predicted value vs. 74%+/-31% of the predicted value; P < 0.05). None of the 33 patients developed respiratory symptoms or had radiologic signs suggestive of lung toxicity. Among the various risk factors examined, baseline DLCO and FEV1 levels were associated with changes in DLCO post-treatment. CONCLUSIONS: This prospective analysis showed that the combination of paclitaxel with carboplatin induced an isolated decrease in DLCO level in the absence of clinical or radiologic evidence of toxicity. Further studies are needed to clarify whether this reduction in DLCO is predictive of subsequent pulmonary impairment.
Aged↗
Accelerated loss of lung function and alveolitis in a longitudinal study of non-smoking individuals with occupational exposure to asbestos.
Long-term asbestos workers who insulate pipes and boilers may develop interstitial lung disease associated with loss of lung function. To quantitate annual loss of lung function, 77 individuals with chest X-rays greater than or equal to 1/0 ILO category who were life-long non-smokers or ex-smokers for greater than 5 years were evaluated. Study parameters included pulmonary function tests and bronchoalveolar lavage for a mean of 3 visits over 30 +/- 2 months. The study participants were 56 +/- 1 years old and had 31 +/- 1 years' occupational exposure to asbestos. At the first visit, multiple regression analysis revealed significant associations between rales or radiographic opacities and VC, FEV1, and total lung capacity; significant associations were also found between neutrophils/ml lavage fluid with FEV1 and diffusing capacity (all p less than 0.05). Annual declines for the asbestos-exposed were VC -92 +/- 28 ml/yr and FEV1 -66 +/- 21 ml/yr. Declines in VC and FEV1 were less in those with reduced lung function at the initial visit. There were no significant associations between any of the annual declines and cells recovered by bronchoalveolar lavage. Compared to other asbestos-exposed cohorts followed longitudinally, asbestos insulators with radiographs greater than or equal to 1/0 and exposure greater than or equal to 20 years have larger rates of FVC and FEV1 decline for both non-smokers and ex-smokers.
Asbestos↗
Recruitment of lung diffusing capacity with exercise before and after pneumonectomy in dogs.
Although the left lung constitutes 42% of the total by weight and volume in dogs, carbon monoxide diffusing capacity (DL) after left pneumonectomy in adults falls less than 30% at rest, indicating a significant increase of DL in the remaining lung. DL normally increases during exercise, presumably by recruitment of alveolar capillaries and surface area as lung volume (Vs) and pulmonary blood flow (Qc) increase. We asked whether the increase of DL in the remaining lung after pneumonectomy in adult dogs could be explained by this kind of passive recruitment by the increased volume and Qc in the remaining lung. We measured the relationship between DL and Qc with a rebreathing technique at increasing treadmill loads in adult foxhounds, before and 6 mo after left pneumonectomy, and the relationship between DL and Vs by the same technique under anesthesia as Vs was expanded. DL was reduced by 29.1% at rest and 26.5% with heavy exercise after left pneumonectomy, indicating either recruitment or new growth in the right lung. With the assumption that the right lung normally receives 58% of the Qc and contains 58% of the DL, DL of the right lung increased with Qc in accordance with the following relationships before and after left pneumonectomy: right lung DL (before pneumonectomy) = 6.44 + 2.40(Qc) (r = 0.963) and right lung DL (after pneumonectomy) = 7.51 + 1.75(Qc) (r = 0.958). Only approximately 7% of the increase in DL from rest to peak exercise could be attributed to the increase in Vs during exercise before pneumonectomy and approximately 15% after pneumonectomy.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Interstitial lung disease in systemic sclerosis.
PURPOSE: To evaluate high-resolution CT (HRCT) parameters of inflammation and fibrosis in systemic sclerosis (SSc), for correlation with lung function, skin scores and exercise tolerance. MATERIAL AND METHODS: 45 SSc patients (40 women, 48.5+/-13.4 years), underwent thoracic HRCT, lung function assessment, and modified Rodnan skin scores. Exercise tolerance was also graded. HRCT were scored for extent of 4 HRCT patterns of interstitial lung disease (ILD): ground glass opacification (GGO), reticular, mixed and honeycomb pattern in each lobe. Total HRCT score, inflammation index (GGO and mixed score) and fibrosis index (reticular and honeycomb scores) were correlated with lung function and clinical parameters. RESULTS: ILD was present in 39/45 (86.7%) patients. Abnormal (<80% predicted) forced vital capacity (FVC), total lung capacity (TLC) and carbon monoxide diffusion factor (DLco) were detected in 30%, 22% and 46% of patients. Total HRCT score correlated with FVC (r=-0.43, p=0.008), FEV1 (forced expiratory volume) (r=-0.37, p=0.03), TLC (r=-0.47, p=0.003), and DLCO (r=-0.43, p=0.008); inflammatory index with DLCO (r=-0.43, p=0.008) and exercise tolerance (r=-0.39, p < 0.05); and fibrosis index with FVC (r=-0.31, p=0.05) and TLC (r=-0.38, p=0.02). Higher total HRCT score, and inflammation and fibrosis indices were found in patients with abnormal lung function. CONCLUSION: Qualitative HRCT is able to evaluate inflammation and fibrosis, showing important relationships with diffusion capacity and lung volume, respectively.
Exercise Tolerance↗
Small airways function in patients with inflammatory bowel disease.
It has been reported that in patients with inflammatory bowel disease (IBD), the airways are involved, and a number of clinical manifestations have been described. The aim of this study was to investigate the function of the small airways in IBD. Thirty patients with IBD (mean age, 47 yr), 12 with Crohn's disease and 18 with ulcerative colitis, were studied and compared with a control group of 16 normal subjects. Maximal expiratory flow-volume curves were performed breathing room air and a mixture of 80% helium, 20% oxygen. The differences of flows at 50% of FVC (delta Vmax50) and the volume of equal flows (Visov) were calculated as indices of small airways function. In addition, spirometry, lung volumes, and diffusing capacity were measured. Visov was statistically significantly greater in patients with either CD or UC than in control subjects (x +/- SD) (24.99 +/- 1.35 and 25.95 +/- 1.5 versus 20.1 +/- 1.39), (p < 0.01 and p < 0.001, respectively). A reduction in TL(CO) was noticed in the active stage of the disease in both groups of patients (p < 0.05). This may indicate that lung parenchyma is also involved in active IBD. Our results suggest that the function of the small airways and diffusion capacity of the lungs are affected in patients with IBD.
Adult↗
Pulmonary involvement in the eosinophilia-myalgia syndrome.
We describe the cases of three women with pulmonary involvement in the eosinophilia-myalgia syndrome. The illness was characterized by elevated peripheral blood eosinophil counts, myalgias, fatigue, and dyspnea. Two of three patients had bilateral infiltrates on chest roentgenograms. All three had markedly decreased carbon monoxide diffusing capacities and pulmonary hypertension. High-dose prednisone therapy provided only partial resolution of the pulmonary symptoms. Open lung biopsy specimens showed chronic interstitial and perivascular infiltrates in two of the patients and moderate fibrointimal hyperplasia of pulmonary vasculature in the third. High-dose prednisone therapy prior to the biopsies may have modified the original histologic features.
Adolescent↗
A bloodless method for measurement of diffusing capacity of the lungs for oxygen.
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Adult↗
[Mechanical effects of obesity on lung function (author's transl)].
Spirometry, blood gases, steady state diffusing lung capacity for carbon monoxyde, ductance for carbon monoxyde were determined in 27 obeses. In 13 of them we also measured closing volume. In 80 per cent of these patients we observed a decrease in expiratory reserve volume certainly due to a shift on the right of the chest wall volume-pressure curve. In 50% of the obeses we found an arterial hypoxia, usually observed when the expiratory level was lower than closing volume. Finally in 20% of the subjects we observed a decrease in diffusing lung capacity and/or ductances probably due to an important fall in and expiratory level at the closing volume level with impairment of the distribution of ventilation.
Adolescent↗
Changes in HRCT findings in patients with respiratory bronchiolitis-associated interstitial lung disease after smoking cessation.
High-resolution computed tomography (HRCT) findings in patients with respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) are varied and nonspecific. There is no known report of changes in HRCT findings and respiratory function test results for RB-ILD patients following the cessation of smoking. Five patients with RB-ILD, confirmed by surgical lung biopsy, were retrospectively studied. Each stopped cigarette smoking and did not receive corticosteroid therapy after diagnosis. The clinical symptoms, respiratory function test results and HRCT findings obtained at the final observation were compared with those from the time of diagnosis. Ground-glass opacity and centrilobular nodules corresponding to pathological respiratory bronchiolitis, as well as intralobular fine linear-reticular opacity corresponding to fibrosis involving the subpleural alveolar septa, showed computed tomography-pathological correlations. Both clinical symptoms and the diffusing capacity of the lungs for carbon monoxide improved significantly following smoking cessation, as did ground-glass opacity and centrilobular nodules seen during the initial HRCT examination. Centrilobular nodules and ground-glass opacity, which are the main features of high-resolution computed tomography of respiratory bronchiolitis-associated interstitial lung disease patients and represent pathological respiratory bronchiolitis, can be improved by smoking cessation. The diffusing capacity of the lung for carbon monoxide in respiratory function tests can be also improved.
Adult↗