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PubMed1978

[Lung function tests in emphysema].

Several lung function tests are capable of detecting typical functional abnormalities in pulmonary emphysema, such as reduced elastic recoil of lung tissue, elevation of intrathoracic gas volumes, expiratory bronchial collapse or uneven patterns of ventilation. The measurement of elastic recoil by means of an esophageal catheter also seems to be a reliable technique for detecting early stages of emphysema, but its use for routine clinical investigations remains impracticable. The elevation of intrathoracic gas volumes determined by body plethysmography or helium dilution technique may sometimes be influenced by reversible bronchial obstructions or additional restrictive ventilatory defects. Expiratory collapse of the intrathoracic airways, however, proves to be a regular finding in advanced pulmonary emphysema. It results from decreased stability of the peripheral and central bronchial wall as well as from a shifting of bronchial and transmural pressure gradients to the peripheral airways. The occurrence of a pressure dependent expiratory stenosis can easily be demonstrated by the spirometric flow-volume curve during forced expiration, thus differentiating patients with asthma from those with chronic bronchitis and emphysema. The minimal program for detection and evaluation of emphysematous alterations of the lung by functional tests should consist in the measurement of intrathoracic gas volumes, recording of the forced expiratory volume and the analysis of the flow-volume curve.

Emphysema↗
PubMed1983

Effect of cromolyn on carbachol-induced bronchoconstriction.

The effect of premedication with cromolyn 40 mg on the bronchial response to inhaled carbachol was investigated in four atopic and four non-atopic subjects with mild asthma. Paired carbachol inhalation tests were carried out on consecutive days in a double-blind fashion following randomized premedication with cromolyn or placebo. Bronchial sensitivity was expressed as the log dose of carbachol provoking a 15% decrease in FEV1 (log PD15 FEV1) or a 30% decrease in FEF25-75 (log PD30 FEF25-75). The mean log PD15 FEV1 was significantly greater following cromolyn compared to placebo (2.34 +/- .22 vs 1.87 +/- .10; mean +/- SE; p less than 0.05) as was log PD30 FEF25-75 (2.30 +/- .16 vs 1.72 +/- .08; p less than 0.005). These results indicate that cromolyn interferes with cholinergic induced bronchoconstriction and support the suggestion that it has an effect at a more fundamental level than the inhibition of antigen induced mediator release from mast cells.

Adult↗
PubMed1980

Effect of freon inhalation on maximal expiratoryflows and heart rhythm after treatment with salbutamol and ipratropium bromide.

The purpose of this investigation was to determine whether inhalation of a freon gas mixture, the propellant of the commercial metered-dose aerosols, consisting of freon 11, freon 12, and freon 114, reduces the bronchodilating effects of inhaled salbutamol or ipratropium bromide or causes cardiac arrhythmias in control, asthmatic and bronchitic subjects. FEV1 and flows measured at different lung volumes on the maximal effort expiratoryflow-volume curve were measured during a period of 6 h. Inhalation of freon caused no significant overall reduction in the salbutamol and ipratropium bromide response in any group. Arrhythmias only occurred among the asthmatic and bronchitic patients, and were most frequent after salbutamol. Ventricular extrasystoles occurred in three cases, all after salbutamol and in two of these in combination with freon inhalation. In one patient there was furthermore hyposia and hypercapnia. The combination of the effects of hypoxia, hypercapnia, catecholamines and freon on the heart is therefore a more likely cause of arrhythmia than the effect of freon alone.

Adult↗
PubMed1980

Reaginic sensitivity to Mus musculus extract in a group of Chicago urban asthmatics.

Thirty-nine out of 103 urban asthmatics reacted on prick test to rodent hair extract (MME). One out of 68 and one out of 50 reacted among suburban asthmatics and normal controls, respectively. Ten skin-test reactive and three non-reactive urban asthmatics underwent bronchial provocative challenge tests (BPT). Results were significant at p less than 0.001. Twenty-one out of 26 skin-reactive and one out of 25 skin non-reactive asthmatics had specific IgE antibody, p less than 0.001. These data suggest that rodent hair might be a relevant allergen in some urban asthmatics.

Adolescent↗
PubMed1983

Patterns of response to inhaled methacholine.

Fifty-two patients with unexplained pulmonary symptoms were tested using inhaled methacholine. Of the 32 who reacted 11 had a greater than 20% decrease in FEV1 (with or without an associated change in FEF25-75%) as the end-point, 15 had a greater than 25% decrease in FEF25-75% as their initial response while 6 had an initial greater than 25% decrease in FEF200-1200. In some but not all subjects in the latter two groups a decrease in FEV1 occurred with increased methacholine concentrations. Changes in FEF25-75% and FEF200-1200 should be considered in documentation of airway hyperreactivity in some patients.

Adolescent↗
PubMed1983

Double-blind evaluation of methylprednisolone versus placebo for acute asthma episodes.

Twenty-eight children with persistent bronchospasm after outpatient therapy were treated for eight days with methylprednisolone or placebo in a prerandomized double-blind manner, in addition to treatment with optimal oral bronchodilators. At follow-up visits 1, 7, and 14 days after onset of therapy, a history was taken and physical examination and pulmonary function tests were performed. Initially and on the 14th day, patients underwent cosyntropin tests of adrenal function. Patients kept daily peak flow charts. Both groups improved with time. However, by 24 hours after starting methylprednisolone therapy, the placebo group continued to show reversibility after isoproterenol inhalation whereas the methylprednisolone group did not. By day 7 there were significantly more patients with normal 1-second forced expiratory volume (FEV1) and forced expiratory flow in the middle half of the forced vital capacity (FEF25-75%) in the methylprednisolone group and mean FEF25-75% was significantly higher for this group (P less than .02). By day 14, six days after finishing treatment with the study drugs, more patients in the placebo group had residual wheezing, but pulmonary function tests were now similar for the two groups. Although both groups showed a decline in cosyntropin responsiveness on day 14 compared with day 1, there was no difference between the steroid- and placebo-treated patients. This study proves that short-term corticosteroid therapy will accelerate resolution of moderately severe and severe-acute attacks of asthma without significant suppression of adrenal function.

Adrenal Glands↗
PubMed1978

Small airway disease: comparison of tests in young smokers versus nonsmokers.

A number of new tests for detection of small airway disease have been developed in the past several years. It is hoped that these will prove valuable as screening tests to detect those at risk of developing obstructive airway disease. We obtained data on the degree of discrimination of single breath nitrogen studies (CV/VC, CC/TLC, deltaN2/L), air-He studies (Vmax50), and the maximal midexpiratory flow (FEF25-75%) in detecting abnormalities in young smokers. Only the CV/VC and CC/TLC significantly separated smokers from nonsmokers, each revealing 20% abnormal values in smokers.

Adult↗
PubMed1982

Spirometric studies in non-smoking, healthy adults.

Reference spirometric values for vital capacity (VC), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), forced expiratory volume in one second as percentage of vital capacity or of forced vital capacity (FEV%), the highest flow during forced inspiration (Vmax insp), the highest forced expiratory flow at 50% vital capacity (Vmax 50%), the highest forced expiratory flow when 75% of vital capacity has been expired (Vmax 25%), Vmax insp/Vmax 50% and peak expiratory flow (PEF) were determined in a series of 296 males and 257 females, 18-65 years old, who have never smoked. Equations were derived using height and age as predictors. The reproducibility was tested.

Adolescent↗
PubMed1980

Evaluation of onset of bronchodilating effect by interruption of the air flow method.

The speed of onset of the bronchodilating effect of ibuterol, a derivative of terbutaline, was measured by the method of air flow interruptions, which enables an almost continuous study of lung resistance before and after the administration of a bronchodilator. In the double-blind comparison between ibuterol and placebo, the onset of action of the new beta 2-agonist has been shown to take place within 30-45 sec. This indicates that ibuterol is a bronchodilator with rapid onset of action.

Adult↗
PubMed1982

The immediate effect of physiotherapy and aerosol treatment on pulmonary function in children with cystic fibrosis.

The direct effect of physiotherapy and physiotherapy produced by aerosol treatment on pulmonary function was studied in 25 sputum-producing patients with cystic fibrosis. Special emphasis was given to the effect on airway upstream to the flow-limiting bronchi. No significant effect on flows and volumes could be found. This may be partly explained by the fact that the percussion frequency and pressure on the chest wall with manual physiotherapy does not lead to optimal penetration of vibration in the lungs and mobilisation of secretions. Theoretically it is unlikely that any physiotherapy technique will be able to enhance the clearance of mucus from the peripheral airways.

Acetylcysteine↗
PubMed1982

An evaluation of the initial treatment of acute asthma.

Two treatment regimens for the initial treatment of acute asthma in 50 patients between the ages of 12 and 20 years seen in the emergency room were evaluated. The treatments were randomized such that 26 patients received 2.5 mg of the beta 2-agonist fenoterol by nebulizer and 24 patients received 0.3 mg of epinephrine followed by 0.75 mg of Sus-Phrine. Clinical assessment and spirometry were performed over a two-hour period. Both groups responded within ten minutes and peak improvement was reached within one hour. Peak expiratory flow and clinical score were better following fenoterol treatment in the first hour (P less than .05). The one-second forced expiratory volume and the forced expiratory flow in the middle half of the vital capacity were greater at 20 minutes with fenoterol (P less than .05). Those with more severe obstruction (forced expiratory volume less than 30%) receiving aerosol therapy also had significantly greater improvement in the first 20 minutes compared with those who received injections. Four patients failed to respond to epinephrine whereas all patients showed improvement with fenoterol (P less than .05). These results demonstrated that an inhaled beta 2-agonist is effective in the initial treatment of acute asthma in children, regardless of severity, and avoids the need for injections.

Acute Disease↗