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PubMed1997

[Pneumoconiosis and exposure to wood].

The authors report a case of an employee in the wood processing industry. The clinical presentation was respiratory with dyspnoea on effort. The chest x-ray showed bilateral interstitial changes. Following bronchioalveolar lavage electron microscopic studies showed evidence of silica particles. Respiratory function tests showed pulmonary performance of 51%-64% of theoretical values depending on the test used. His working position involved the up keep of the boilers and also the drainage of the silos for wood dust. The wood used was corupixa, a brazilian wood containing crystalline silica; 0.1% in fresh wood dust. Numerous analyses have specified the percentage of silica in the ashes in magma. The diagnosis of pneumoconiosis of the silicotic type was sustained. The occupational risk linked to using this type of wood should be understood and the need to take protective measures for the employees concerned.

Adult↗
PubMed1997

[Ergospirometry].

Explore the source record for details and available documents.

Ergometry↗
PubMed1998

[Rolled atelectasis and asbestosis. Apropos of 26 patients].

Round atelectasis (AE) is a benign form of respiratory problem which develops due to fixing of the visceral pleura. This lesion for which the principal cause is exposure to asbestos may pose problems of differential diagnosis with bronchopulmonary cancer. In a cohort of 286 patients suffering from benign asbestos related pleural disease the diagnosis of round atelectasis was made on computerized tomography in 26 patients (31 AE) on the following criteria: rounded opacities of less than 7 cm in diameter situated at the periphery of the lung in contact with a thickened pleura with an acute angle linking the pleura and the opacity, a reduction of lung volume on the side of the atelectasis and the presence of a "comet tail sign". These patients were investigated to specify the circumstances of the occurrence, including their symptomatology, the changes in lung function, the topography of the round atelectasis and the associated radiological signs. Intense exposure to asbestos either continuous or discontinuous was found in 19 patients; 20 patients presented with some respiratory symptoms (dyspnoea 15/26, cough 11/26 and chest pain 9/26) but the reduction in lung function was moderate (7 had restrictive ventilatory trouble, 4 obstructive problems and a mixed problem in 1). The preferred localisation for round atelectasis was in the inferior lobes in the posterior basal lateral vertebral area (26/31) which may explain their being frequently missed on the standard radiograph (only one case of round atelectasis was visible on the straight chest radiograph in our study). An understanding of the pathology and the computered tomographic characteristics are now well defined and should enable an unnecessary diagnostic thoracotomy to be avoided which besides has no justification from the functional point of view.

Asbestosis↗
PubMed1976

[Early changes of respiratory function in mitral valve stenosis].

In order to detect early changes of respiratory function in patients affects by pure mitral valve stenosis, the authors selected 12 patients-non smokers, without symptoms of respiratory disease, of I and II NYHA class. In all subjects right and left cardiac catheterization and conventional spirometric measurements were performed. Then maximal mid-expiratory flow (MMEF), maximal expiratory flow at 50% of vital capacity (MEF 50%), maximal expiratory flow at 25% of vital capacity (MEF 25%), closing volume (CV) and closing capacity (CC) were determined, to find a small airways (bronchi of caliber inferior to 2 mm) disease. Whereas conventional spirometric measurements showed normal values, the small airways disease was proved by MEF 50% and MEF 25% measurements. The small airways obstruction observed by the authors may be due to: a) dilatation of pulmonary vessels because of venous congestion resulting in the compression of adjacent small airways; b) partial bronchiolar obstruction because of congestion of submucous venous plexus; c) interstitial oedema due to increase of extravascular pulmonary water because of pulmonary venous congestion.

Adult↗
PubMed1980

Flow-volume curve contour in COPD: correlation with pulmonary mechanics.

A study was designed to evaluate the diagnostic usefulness as well as the mechanical determinants of the flow-volume contour in chronic obstructive pulmonary disease (COPD). Twenty patients with COPD of varying etiology were divided equally into two groups. Group 1 had an airway collapse pattern (described in the text) designated type 1, and group 2 had a more curvilinear obstructive pattern designated type 2. Pressure, volume, and flow relationships were examined. The results of our studies showed that a type 1 flow-volume contour in a patient with obstructive airways disease suggests a critical combination of central and peripheral airway collapse at high lung volumes with loss of elastic recoil. However, not all patients with loss of recoil will exhibit this contour. Persistence of type 1 contour suggests that there is a component of airway instability which may be irreversible.

Adult↗
PubMed1986

Large airway size, lung size, and maximal expiratory flow in healthy nonsmokers.

It has been postulated that airway size and lung size may be dissociated because of developmental differences between the tracheobronchial tree and the pulmonary parenchyma (dysanapsis). To test this hypothesis, we compared measurements of airway size (diameters, cross-sectional area, length and volume of the trachea, diameter and cross-sectional area of the mainstem bronchi) and lung size (total lung capacity, thoracic diameters, lung length), as determined from plain chest radiographs in 79 male and 86 female healthy nonsmokers. In both groups of subjects, the correlation between indexes of airway size and lung size was low. Airway size was not significantly different between men and women, when standardized for lung size. Tracheal diameter and length tended to increase with age. To assess the value of airway size measurements in the prediction of maximal expiratory flow, we compared tracheal and bronchial size with FVC, FEV 0.5, FEV1, and mean forced expiratory flow during the middle half of VC. The correlation between airway size and spirometric indexes was very low. Multiple regression analysis showed that the use of airway size variables in addition to the age and height variables did not substantially improve the prediction of maximal expiratory flow. Our results are consistent with the dysanapsis hypothesis, but they suggest that the introduction of radiologic estimates of large airway size in the prediction equations relating maximal expiratory flow to age and height is not justified, at least in the general population.

Female↗
PubMed1980

Density dependence of expiratory flow and bronchodilator response in asthma.

Change in the magnitude of density dependence of the maximal expiratory flow (D/MEF) following inhalation of isoproterenol was used as a test for predicting the long term response to isoproterenol vs atropine in 24 adult patients with longstanding asthma. Eleven subjects showed a decrease in D/MEF manifested by increase in volume of isoflow (VisoV) and/or decrease in Vmax50 Helox/air following isoproterenol inhalation (group 1). Thirteen subjects manifested an opposite response (group 2). Atropine sulphate (0.08 mg/kg) and isoproterenol hydrochloride (2.5 mg) were then administered by inhalation, each four times a day for seven days in a randomized double-blind cross over fashion to all subjects. One of group 1 but ten of group 2 subjects had a greater subjective and objective improvement with atropine than with isoproterenol (P less than .005). An increase in D/MEF following isoproterenol can be used as a test to predict a better response to atropine than to isoproterenol over a one week period. Such a response occurs in almost half of the adult chronic asthmatic patients. The results are consistent with a preferential dilatation of the large airways by atropine.

Adult↗
PubMed1986

Relationship of tracheal size to maximal expiratory airflow and density dependence.

Wave-speed theory predicts that maximal expiratory flow (MEF) at high lung volumes depends strongly on size of central airways. We tested this prediction by correlating MEF and tracheal cross-section area (T-XSA) in 15 (11 males, 4 females) healthy never-smoking volunteers. T-XSA was determined by planimetric analysis of contiguous 1-cm computerized tomographic scans of the intrathoracic trachea. We found a significant correlation between T-XSA at total lung capacity (TLC) and flow at 75% of vital capacity (V75) (r = 0.88, P less than 0.001). This contrasted to the correlation found between lung volume at TLC and V75 (r = 0.60). Density dependence of airflow (percent increase in V75 in air) was 35 +/- 17% and showed a significant inverse relationship to T-XSA (r = 0.70). These results confirm predictions of wave-speed theory and demonstrate the importance of cross-sectional area of central airways in determining MEF at high lung volumes. The large variability of MEF in normal individuals partly represents variations in tracheal size. Poor correlation between lung size and airway size suggests only a loose coupling between airways and lung parenchyma consistent with dysanaptic growth. Our findings indicate that changes in density dependence of airflow are not solely determined by the status of small airways and that differences in tracheal size contribute to its variability.

Adult↗
PubMed1976

Effect of helium on maximal expiratory flow in patients with asthma before and during induced bronchoconstriction.

The effect of breathing helium on maximal expiratory flow at 50 per cent of vital capacity (V50) was studied in 27 patients with asthma during remission and during induced bronchoconstriction. Nine patients gave a history of asthma induced by exercise; two had asthma due to timothy pollen allergy, and the remaining 16 had asthma due to exposure to western red cedar. Bronchoconstriction was induced by exercise in 10 patients, timothy pollen in 4 patients, methacholine in 4 patients, and red cedar in 16 patients. During remission, the increase in V50 with helium (deltaV50He) was greater than 20 per cent in 22 patients who were classified as responders; deltaV50He was less than 20 per cent in the remaining 5 patients, who were classified as nonresponders. There was a significant correlation between the severity of airway obstruction as measured by V50 and the response to helium, both during remission and during induced bronchoconstriction; however, there was no correlation between helium response and specific airway conductance. In general, patients who were responders during remission remained responders during induced bronchoconstriction, and nonresponders remained nonresponders, regardless of the method of challenge or the type of reaction (immediate verus late). There were a few exceptions in which a responder became a nonresponder during severe bronchoconstriction. The results of this study suggest that in most patients with asthma, the site of airway obstruction is likely to be in the large airways and, in most cases, remains constant in an individual asthmatic; however, an asthmatic who is a helium responder may become a nonresponder during severe bronchoconstriction.

Adult↗
PubMed2003

Effects of reduction mammaplasty on pulmonary function and symptoms of macromastia.

A number of studies have documented subjective improvement in somatic and psychological symptoms following breast reduction surgery. Objective data demonstrating improved postoperative function have been more difficult to assess, and particularly with respect to pulmonary function, the results have been contradictory. In this prospective study, patients completed a comprehensive preoperative questionnaire modified from the American Thoracic Society Division of Lung Diseases Epidemiology Standardization Project (1978). This questionnaire noted subjective pulmonary symptoms and pulmonary medical history. In addition, subjective symptoms related to breast size, including back and neck pain and shoulder pain and grooving, and a subjective evaluation of body image, were evaluated. All subjects received preoperative pulmonary function testing, including spirometry, lung volume measurements, and measurement of peak inspiratory and expiratory flow rates and pressures. Eight weeks after breast reduction, a repeat questionnaire and pulmonary function testing were administered. Preoperative and postoperative pulmonary function values were compared using Cochran-Mantel-Haenszel tests, and correlations were tested between changes in pulmonary function test values and subjective symptom improvement. Forty-four patients underwent an average of 2228-g bilateral reduction. All of these patients had their surgical procedures preauthorized as medically necessary by their insurance carriers. All subjective parameters examined were statistically significantly improved following breast reduction (p < 0.001). Of the 17 patients with preoperative complaints of shortness of breath, all noted significant improvement following breast reduction surgery (p < 0.001). Of the objective pulmonary criteria evaluated, inspiratory capacity, peak expiratory flow rate, and maximal voluntary ventilation showed a statistically significant improvement following surgery (p < 0.05). These changes correlated with body mass index; the greater the index, the greater the change in maximal voluntary ventilation and peak expiratory flow rate. Smokers in this group had the largest change in maximal voluntary ventilation (p < 0.008). No correlation could be found between preoperative pulmonary symptoms, a single subjective symptom, or grams of breast weight reduction and changes in pulmonary function tests. The results show that pulmonary parameters, related primarily to work of breathing (inspiratory capacity, maximal voluntary ventilation, peak expiratory flow rate), were statistically improved following breast reduction surgery, and these changes correlated with body mass index.

Adolescent↗
PubMed1987

Density dependence of maximal expiratory air flow in asthmatics with exacerbation of their disease.

In an effort to evaluate the relationship between the site of air-flow obstruction and rate of improvement with therapy, we studied 20 asthmatics with spirometry, before and after bronchodilator, using air and 80% helium-20% oxygen (He-O2). Studies were obtained on 3 consecutive days after hospital admission and approximately 18 days after discharge. Greater He-O2 response ([Vmax50(He-O2)--Vmax50(air)]/predicted Vmax50) X 100, was associated with: less cigarette consumption (p less than 0.02), lesser frequency of chronic productive cough (p less than 0.02), more symptom-free intervals (p less than 0.02), and greater frequency of allergic rhinitis (p less than 0.03). Patients with greater He-O2 response (Group 1) reached maximal improvement in air flow by Hospital Day 2, whereas those with a lesser He-O2 response (Group 2) continued to improve throughout the observation period. The Group 1 mean peak expiratory flow rate (PEFR) improved by 24% of predicted per day to maximum, which was significantly greater (p less than 0.025) than the 11% per day rate of improvement of Group 2. The He-O2 response remained relatively stable throughout the course of the study except for 3 patients who dramatically improved their response with therapy. A highly significant correlation, adjusted for regression to the mean, (r = 0.95, p less than 0.0001) was found between mean baseline percent predicted Vmax50 and the mean He-O2 response. After adjustment for regression to the mean, there was no significant relationship between the degree of prebronchodilator He-O2 response and increase in He-O2 response with bronchodilator.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗