| Acute changes of lung volumes and lung mechanics in asthma and in normal subjects. | |
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MedLine Citation:
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PMID: 684678 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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Lung volumes, pulmonary mechanics, and specific airway conductance (sGaw) were studied before and 15 minutes after 200 microgram of aerosol salbutamol in nine asthmatics undergoing mild spontaneous exacerbations of their disease and in five normal subjects. In addition, three of the normal subjects were studied after voluntarily breathing at high lung volumes for one minute. The normal subjects and four of the asthmatics showed no overall changes in lung volumes or pressure-volume (PV) curves after salbutamol, even though airway dilatation was produced in the asthmatic subjects. In another five asthmatics, salbutamol induced a significant fall in the total lung capacity (TLC) in three, and in the residual volume and functional residual capacity in all five. There was a significant displacement of the PV curve downwards and to the right in all five, with increased lung compliance (Cl stat) in two. The fall in TLC could be accounted for by the increase in lung elasticity. There is reason to believe that this change in lung mechanics could be due to the reversal of asthma-induced stress relaxation. Sustained breathing at high lung volume is known to cause stress relaxation of the lung. However, this breathing pattern did not alter the PV curve or TLC in two of three normal subjects, which is consistent with stress relaxation being rapidly reversible. The other normal subject had an acute shift of the PV curve upwards and to the left after breathing at high lung volume. It has been concluded that stress relaxation is usually rapidly reversed but that in some individuals it may only be slowly reversed. This more persistent form of stress relaxation may contribute to the acute changes of TLC found in some asthmatics. |
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Authors:
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P W Holmes; A H Campbell; C E Barter |
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Publication Detail:
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Type: Journal Article |
Journal Detail:
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Title: Thorax Volume: 33 ISSN: 0040-6376 ISO Abbreviation: Thorax Publication Date: 1978 Jun |
Date Detail:
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Created Date: 1978-10-18 Completed Date: 1978-10-18 Revised Date: 2009-11-18 |
Medline Journal Info:
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Nlm Unique ID: 0417353 Medline TA: Thorax Country: ENGLAND |
Other Details:
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Languages: eng Pagination: 394-400 Citation Subset: IM |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Adult Airway Resistance Albuterol / diagnostic use Asthma / physiopathology* Female Forced Expiratory Volume Functional Residual Capacity Humans Lung / physiopathology* Lung Compliance Male Middle Aged Total Lung Capacity Vital Capacity |
| Chemical | |
Reg. No./Substance:
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18559-94-9/Albuterol |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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