摘要:

The effect of acute isovolemic anemia on the control of respiration was examined in chemodenervated decerebrate cats to determine whether the peripheral chemoreceptors are normally responsible for the reported respiratory indifference to a reduction in blood hemoglobin. The tidal volume/CO2 response lines and the respiratory frequency/ tidal volume relationship were determined during inhalation of air and of oxygen with the Hering-Breuer pulmonary stretch reflex intact and interrupted. No difference in respiratory control behavior was detectable between initial and anemic conditions (hematocrit reduced by 40–50%). We conclude that no respiratory compensation is afforded by the peripheral chemoreceptors in anemi

ISSN:0025-7931    

DOI:10.1159/000194456

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The clinical findings, occupational exposure, smoking history, pulmonary function, chest radiograph and ventilation-perfusion studies have been examined in 12 men exposed to asbestos fibers in the course of their work. Minor abnormalities of regional ventilation, consistent with early small airway dysfunction, were found in the fibrotic zones of most of the nonsmokers or mild cigarette smokers. The whole-lung washout times, estimated by visual inspection of serial washout images, were strongly correlated with measurements of airflow obstruction, but not with pack-years of smoking. There was a close correspondence between the radio-graphic extent of pulmonary fibrosis and the abnormalities in pulmonary blood flow in these regions. The severity of the abnormalities in regional pulmonary blood flow was significantly correlated with the years of asbestos exposure (r = + 0.73, p < 0.01). It is suggested that the magnitude of the disturbance in pulmonary blood flow in the fibrotic zones could be used to estimate the proportion of pulmonary dysfunction due to asbestos exposure.

ISSN:0025-7931    

DOI:10.1159/000194457

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Among individuals of comparable size with normal lungs, short-term breathing capacity varies widely for unknown reasons. If the velocity of ventilatory muscle contraction limits airflow, then persons with a high proportion of fast twitch fibers in the ventilatory muscles should have large ventilatory capacities. As one test of this hypothesis, we correlated ventilatory capacity with vertical jump, an index of leg and thus of diaphragmatic muscle fiber composition. We found significant positive correlations between vertical jump and the 12-second maximal voluntary ventilation in both women (n =19, r = 0.6; p < 0.01) and men (n = 25; r = + 0.4; p = 0.06). Both correlations were independent of body weight or vital capacity. These results are consistent with the hypothesis that short-term ventilatory capacity is influenced by the contractile characteristics of the ventilatory muscles.

ISSN:0025-7931    

DOI:10.1159/000194458

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The effects of tobacco smoke on the central and peripheral airways were assessed in humans and rats by direct and indirect methods. In both species tobacco smoke affected the central and peripheral airways. In humans there were apparent decreases in the 1-second forced expiratory volume, peak expiratory flow rate and significant increases in closing volume and closing capacity (P < 0.001). In rats significant changes were seen in specific airway resistance from the 6th week of exposure onwards. Similarly, airway luminal diameter decreased markedly in tobacco-exposed animals to subthreshold concentrations of acetylcholine (10-8M), This decrease was also exposure time dependent. The increased responsiveness of the respiratory system has been attributed to inter alia: (1) increased vagal activity; (2) increased mucus production leading to decreased airway lumen; (3) mucosal swelling due to changed ionic constellation; (4) disturbance of the lungs’ defense mechanism; (5) imbalance in and easy accessibility to the adrenoceptor

ISSN:0025-7931    

DOI:10.1159/000194459

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Relationship between stature and roentgenologically determined lung sizes was examined in 48 patients (mean age = 24.6 ± 6.2 years) with spontaneous pneumothorax, 46 male patients (mean age = 24.6 ± 3.8 years) with various diseases not related to the cardiopulmonary system, and 48 healthy male students (mean age = 24.3 ± 2.2 years). Patients with spontaneous pneumothorax were slender compared to the control groups but the body height was not different. The patients had significantly longer lungs than the controls, although width and depth of the lungs were similar between the three groups. Mean differences for the lung height between patients and healthy students were so small (mean = 1.2–1.7 cm, which is equivalent to 0.3–0.7 cm H2O) that stress alone does not appear to be a major contributor to the pathogenesis of spontaneous pneumo

ISSN:0025-7931    

DOI:10.1159/000194460

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The arterial oxygen and carbon dioxide tensions (PO2 a and PCO2 a) and pHa were measured in 73 patients using capillary blood from a vasodilated ear lobe in the supine, sitting and standing positions. 46 patients had no known lung or heart disease and 27 patients had chronic obstructive airway disease (COAD). There was a significant age-related decrease in PO2 a. There were essentially no significant differences in PO2 a between the three positions in asymptomatic patients of different age-groups or in patients with COAD.

ISSN:0025-7931    

DOI:10.1159/000194461

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The authors have studied the action of carbon monoxide on the affinity of hemoglobin for oxygen by measuring P50 in whole blood and in stripped hemoglobin before and after exposition of blood samples from heavy smokers and polycythemic patients with high levels of HbCO (7.92 ± 0.7%) to hyperbaric oxygen (2.2 ata). The concentration of 2,3-diphosphoglycerate was normal although P50 was significantly lowered, not only in whole blood but also in stripped hemoglobin (2 p < 0.001). Hyperbaric oxygen normalized P50 by removing CO radicals from stripped hemoglobin. This may indicate that CO radicals exert a direct action on the hemoglobin molecule, at least at the HbCO levels studied in this work

ISSN:0025-7931    

DOI:10.1159/000194462

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The effects of atropine methonitrate and salbutamol delivered by wet nebulisa-tion, separately and in combination, were studied in 22 patients with chronic airways obstruction. Atropine methonitrate 1.5 mg, 3.0 mg and 6.0 mg, salbutamol 2.5 mg, 5.0 mg and 10.0 mg and the intermediate dose of each agent in combination were used. Peak expiratory flow rate (PEFR), forced expiratory volume in 1 s (FEV1.0) and forced vital capacity (FVC) were measured. Improvement in the measured variables was greater after salbutamol, alone or with atropine, up to 3 h after inhalation, after salbutamol with atropine 4 and 6 h after inhalation, and after atropine, alone or with salbutamol, 12 h after inhalation. For all patients together there were no significant differences in the mean maximum PEFR, FEV1.0 or FVC that were achieved following atropine, salbutamol or both together. Salbutamol, 5.0 or 10.0 mg, and atropine methonitrate, 1.5 or 3.0 mg, were maximally effective in most patients and at these doses serious side effects were unusual.

ISSN:0025-7931    

DOI:10.1159/000194463

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Oxitropium bromide (Ba 253) is a new inhaled bronchodilating agent with anticholinergic properties. The effect of this compound (100 μg) was compared to that of ipratropium bromide (40 μg), the β2-receptor stimulant fenoterol (400 μg) and placebo in 8 patients with exercise-induced asthma. The drugs were administered by metered dose inhalers, after which exercise tests were performed on ergometer cycles at the times of the drugs’ maximal effects. Forced expiratory volume during 1 s and vital capacity were recorded basally, repeatedly during 20 min after exercise and following the inhalation of isoprenaline (160 μg) which was given 20 min after exercise. Fenoterol possessed a very good protective effect against exercise-induced bronchoconstriction in all patients, whereas the other drugs differed very little from placebo. Thus, only 4 patients did benefit from ipratropium bromide, 1 patient from oxitropium bromide and 2 patients from placebo. No side effect occurred. In the doses used the two anticholinergic agents ipratropium bromide and oxitropium bromide were less effective than a β2-adrenoreceptor stimulant like fenoterol in protecting against exercise-induced

ISSN:0025-7931    

DOI:10.1159/000194464

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The direct effect of mucolytic agents aerosol on the ultrastructure of the tracheal epithelium of healthy rabbits was studied. Due to the function of mucolytics the ciliated cells are not altered significantly, the goblet ones are overstimulated and injured and after rapid evacuation of mucus they degenerate and are expelled from the epithelium. There are pronounced quantitative differences in the degree of damage caused to the airway epithelium by propylene glycol (10%) plus Broncholysin (20%), 20% Broncholysin, 10% Broncholysin or 4% Mistabron. Most pronounced injury of the epithelium was produced due to propylene glycol-Broncholysin application, 4% Mistabron is the least irritating substance, the next suitable mucolytic solution is 10’% Broncholysi

ISSN:0025-7931    

DOI:10.1159/000194465

出版商:S. Karger AG    

年代:1982

数据来源: Karger