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PubMed1989

Inverse correlation of expiratory lung flows and sputum eosinophils in status asthmaticus.

Seventy-six consecutive patients admitted to Los Angeles County General Hospital with acute asthma were studied. Blood and sputum smears for cell counts were obtained on all patients within 12 hours of admission. Fifty-one (67%) patients were able or willing to perform spirometry and flow/volume curves in the first 24 hours of hospitalization. The severity of airway obstruction as assessed by forced expiratory volume in one second (FEV1), maximum mid-expiratory flow rate (MMFR), and forced vital capacity (FVC) was compared with blood and sputum eosinophil counts. Although there was no relation between the blood eosinophilia and airway obstruction, an inverse relationship between the number of eosinophils in the sputum and airway flow rates was observed. Higher percentages of sputum eosinophils were associated with diminished flow rates. We believe that sputum eosinophils may be helpful in the initial assessment of severe bronchial asthma.

Adolescent↗
PubMed1988

Bronchoconstriction due to exercise combined with cold air inhalation does not generally influence bronchial responsiveness to inhaled histamine in asthmatic subjects.

We investigated immediate and late changes in airway responsiveness to histamine, after bronchoconstriction due to exercise combined with inhalation of cold air, in ten asthmatic subjects who came on six days. On the first visit, the provocation concentration producing 20% fall in FEV1 (PC20) histamine was obtained. After functional recovery, each subject walked on a treadmill whilst breathing dry, cold air. This resulted in an immediate fall greater than 15% (mean +/- SD = 31.9 +/- 11.0%) in forced expiratory volume in one second (FEV1). Following recovery, PC20 was measured again. FEV1 was then monitored for up to 6-8 h. PC20 was measured then and on the two following days at the same time of the day. Subjects were studied on three control days using the same design except that a resting period replaced the exercise with cold air. The mean changes in PC20 at each interval after exercise combined with cold air were not statistically significant. Physiologically significant changes were obtained in only two subjects, reaching a maximum 8 h after the manoeuvre. In these subjects, changes in PC20 were reproducible during a second series of visits. It is concluded that bronchial responsiveness to histamine is not generally influenced by the bronchoconstriction due to exercise combined with cold air.

Adolescent↗
PubMedDate not supplied

FEF200-1200, FEF25-75% and FEF75-85% in non-smokers of either sex and in male smokers residing at an altitude of 2150 M above MSL in Himachal Pradesh.

Forced expiratory flow (FEF) rates were determined for 170 (130 males and 40 females) healthy adults of Himachal Pradesh in the age group of 19-26 years for males and 19-22 years for females. The subjects had been staying at an altitude of 2150 M above mean sea level (MSL) for at least three years prior to the conduct of the study. FEF200-1200, FEF25-75% and FEF75-85% were found to be high as compared to those reported from most other parts of the country. The results were found comparable with those reported from certain populations in U.S.A. Further, the flow rates of the non-smoker males were compared with those of the male smokers. FEF75-85% in smokers was significantly less than that of non-smokers, whereas the differences in FEF200-1200 and FEF25-75% were found to be nonsignificant.

Adult↗
PubMedDate not supplied

Spirometric reference values from a Mediterranean population.

Maximal expiratory flow-volume (MEFV) curves were measured in 1044 healthy nonsmoking volunteers living in the Barcelona area, as part of a larger interhospital project to obtain reference values of pulmonary function tests. Forced vital capacity (FVC), one-second forced expiratory volume (FEV1), FEV1/FVC, %, forced maximal mid-expiratory flow (FEF25-75%), peak expiratory flow rate (PEF) and maximal expiratory flow at 50 and 75% of FVC (MEF50% and MEF25% respectively) were obtained and expressed at BTPS conditions. Techniques and equipments followed both the recommendations of the American Thoracic Society (ATS) and of the European Community for Coal and Steel (ECCS). Prediction equations for age 20 through 70 were calculated for both sexes from a final sample composed of 870 adult subjects, 443 males and 427 females. Simple linear equations using height, age and body weight predicted all spirometric variables as well as more complex equations except MEF25%. Logarithmic equations were proposed for MEF25% to correct for the heteroscedasticity shown in a simple linear model. To our knowledge, this study provides reliable spirometric equations from a large urban Mediterranean sample which were lacking so far in the literature.

Adolescent↗
PubMed1986

[Spirometric parameters of the working population of young non-smoking males of the Murcia area].

A prospective study on dynamic spirometric parameters on 195 healthy non-smoking men-workers, representing the non-smoking labor population from 16 to 40 years of age, in the Murcia Region (Spain), has been carried out. Men were selected upon two criteria: age and height. Lower normality limits, have been estimated with 95% reliability by developing regression equations for the following spirometric parameters: forced vital capacity, forced expiratory volume (timed and relative), peak flow and forced mid-expiratory flow.

Adolescent↗
PubMed1986

The value of the forced expiration technique with and without postural drainage in adults with cystic fibrosis.

The effect of the Forced Expiration Technique (FET) with or without Postural Drainage (PD) was examined in eight adults with cystic fibrosis. On four mornings the patients followed a 30-min physiotherapy session consisting in a randomized order of either FET in a sitting position following a night of horizontal sleep ("FET"), or FET in a postural drainage position following sleep including postural drainage ("FET/PD"). The lung function parameters studied did not change during either of the two treatments. Sputum yield over 22.5 h before the physiotherapy sessions and over 24 h increased with PD during sleep in patients with more than 30 g of sputum per 24 h (p less than 0.05). PD during the treatment sessions did not further increase sputum production. This study indicates that sleeping head-down improves expectoration in patients with copious sputum. PD during FET is not needed after sleeping in the head-down position.

Adolescent↗
PubMedDate not supplied

Successive effects of a vagolitic and a betadrenergic in the differential diagnosis of nonimmunologic and allergic asthma.

In order to determine whether the vagal mechanism is predominant in the physiopathology of asthma, we investigated in the first part of this work. If the new vagolithic, ipratropium can improved the respiratory parameters of asthmatic patients. If the effect is complete or admits yet the supplementary effect of a betadrenergic, Fenoterol. 46 asthmatic patients were registered in some spirographic parameters, e.g. FEV1 (Forced Expiratory Volume in 1 sec.), MMFR25-75 (Maximum Mid-expiratory Flow Rate between the 25 per cent and the 75 per cent of the forced vital capacity) and FEF 200-1200 (Forced Expiratory Flow between 200 ml. and 1200 ml. of the forced vital capacity). The same registers were made 30 minutes after aerolization with 0.05 mg of Ipratropium (two shots) and 10 minutes after 60 micrograms of Fenoterol (three shots). It was found that 78.5 per cent of the patients improved one of the parameters with Ipratropium more than 20 per cent. But 58 per cent of the patients showed an additional improvement with the betadrenergic in one or more of the parameters. This shows that in many cases the physiopathology of asthma is mixed, vagal and betareceptor dependent, in which the medication with Ipratropium plus Fenoterol will obtain better results. Only in some patients the bronchial spasm is vagolithic dependent exclusively, while few others responded to betadrenergic and only 9 per cent of patients did not respond to either one. In the second part of this work we tried to verify if by anamnestic inquiry and additional use of Ipratropium and Fenoterol it is possible to recognize one group of patients with asthma produced by nonimmunologic irritant factors acting on the large airways from another group with asthma due to inhalants allergens and spasm of the small bronchi. The same 46 patients were divided in two groups: Patients who recognize that asthmatic accesses begin after exercise, laughter cold weather, cigarette smoker exposure sprays, synthetics and insecticides. This is the predominantly irritative nonimmunologic group. Patients who recognize that coughing or wheezing begins after contact either with pollen, dust or danders. This is the predominantly allergic group. We proved that patients A improve more with Ipratropium and the opposite is true with patients B. The results with the two drugs are roughly parallel to the anamnestic records.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMedDate not supplied

[Forced expiration index, signal and noise].

Although forced expiration measurements are extensively used, there is no general agreement concerning the best way to quantify the data. In this context, it may be of interest to examine indices from the point of view of their signal/noise ratio. The signal depends upon the actual sensitivity of the index to the kind of abnormality which is to be detected. In general, the relationship between signal and degree of abnormality is strongly non-linear, so that sensitivity is not a constant. The noise depends upon the kind of investigation which is made. When a subject is compared to himself (bronchomotor challenge, follow-up studies, etc.), it is mainly due to intraindividual variability. FEV1 is an example of index with a low sensitivity to peripheral airway abnormality, but a high reproducibility, so that its signal/noise ratio for paired measurements is comparatively good. When two groups are to be compared, the relevant noise is interindividual variability. Coefficient of variation of transit times and slope ratios are quite effective in detecting abnormalities in young smokers, probably because their sensitivity to mild peripheral airway disease is large compared to their interindividual variability. It follows that, according to the type of study, as well as to the nature and extent of abnormality, many indices may qualify as being the best.

Forced Expiratory Flow Rates↗
PubMedDate not supplied

Pulmonary function tests--a comparison between urban industrial and rural agricultural workers of Andhra Pradesh.

Physical parameters and pulmonary function tests (VC, FEV1, FEV1% and FEF25-75%) were collected in 112 urban industrial workers and 104 rural agricultural workers. These average values, values according to age and smoking habits were compared between urban and rural workers. Inspite of no differences in age, rural workers average height, weight, BSA is significantly lower than urban workers. A significant increase in VC value to the extent of 0.22 lit (7.1%), significantly lower FEV 1% value by 4.7% and reduce FEF25-75% value (4.7%) is demonstrated in rural than urban workers. Smoking is shown to produce airway obstruction in both urban and rural workers. A wide variation of PFT values between the present workers and other reported values in India is observed. This study indicates rural workers have better pulmonary capacity and less flow rates than their urban counterpart.

Adult↗
PubMed1993

Respiratory function in precapillary pulmonary hypertension.

Since dyspnoea on exertion is very often the first symptom of precapillary pulmonary hypertension (PPH), either from chronic thromboembolic pulmonary hypertension (CTEPH) or from idiopathic pulmonary hypertension (IPH), these patients are often first examined in a pulmonary function laboratory. We carried out a retrospective study (1987-1992) on pulmonary function in 34 patients diagnosed to have PPH by means of specific diagnostic tools, out of 5,467 patients first attending our laboratory. Nine suffered from IPH, 10 from CTEPH and 15 from Eisenmenger physiology. This last group differed from the others, since its diagnosis had been known for a long time and the stage of the disease was more advanced, when pulmonary function tests were performed in our laboratory (with a view to transplantation). Respiratory function, blood gases and arterial oxyhaemoglobin saturation (HbSaO2) during exercise (Bruce protocol), diffusing capacity of the lungs for carbon monoxide (DLCO), shunt fraction (QS%) (approximation obtained from arterial oxygen tension (PaO2) after 100% oxygen breathing) had been evaluated. In the first two groups, in contrast to other reports, we could observe no obstructive defect. Only 20% of the subjects had restrictive defects, however mild. The typical functional picture of these patients revealed normal lung volumes, normal or slightly reduced DLCO, mild hypoxaemia with hypocapnia, severe HbSaO2 drops during exercise, and pathological QS%. We conclude that every time a patient presents with breathlessness at rest or on exercise, a normal chest X-ray and respiratory function tests, pulmonary hypertension must be suspected and subject to specific and invasive tests. More severe functional impairment was observed in the PPH from the Eisenmenger disorder. This might be due to a more advanced stage of this type of hypertension at the time of our observation and/or to the different mechanisms of the diseases themselves.

Adult↗
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↗
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↗