| Rib cage deformation during static inspiratory efforts. | |
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MedLine Citation:
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PMID: 468626 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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Patterns of rib cage (RC) deformation were studied in six normal subjects during moderate static inspiratory efforts such that esophageal pressure (Pes) as an index of transthoracic pressure fell to between -30 and -60 cmH2O during each maneuver. At lung volumes below 50% inspiratory capacity (IC), static inspiratory efforts deformed RC to a more elliptical shape; RC lateral diameter became smaller and RC lateral diameter became larger. However, at high lung volumes (greater than 50% IC) the opposite change in RC dimensions occurred despite similar changes in Pes, i.e., the RC became more circular. These differences in RC deformation did not appear to be a possive consequence of increased lung volume because the RC could be voluntarily deformed to a more circular shape at low lung volume when a) subjects performed static inspiratory efforts mainly with their intercostal and accessory muscles rather than their diaphragm as judged by a smaller change in transdiaphragmatic pressure for the same Pes; or b) subjects statically contracted their diaphragm with it held in a relatively flattened configuration as assessed by a large abdominal AP dimension. We suggest that deformation of the RC during static inspiratory efforts is not as predictable as has previously been suggested but depends on the pattern of contraction and configuration of the respiratory muscles. |
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Authors:
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N A Saunders; S M Kreitzer; R H Ingram |
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Publication Detail:
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Type: Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: Journal of applied physiology: respiratory, environmental and exercise physiology Volume: 46 ISSN: 0161-7567 ISO Abbreviation: J Appl Physiol Publication Date: 1979 Jun |
Date Detail:
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Created Date: 1979-10-17 Completed Date: 1979-10-17 Revised Date: 2006-11-15 |
Medline Journal Info:
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Nlm Unique ID: 7801242 Medline TA: J Appl Physiol Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: 1071-5 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 Obstruction Diaphragm / physiology* Humans Intercostal Muscles / physiology* Lung / physiology Lung Volume Measurements Male Pressure Respiration* |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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