Document Detail


Intrapleural fluid movements described by a porous flow model.
MedLine Citation:
PMID:  1490964     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We injected technetium-labeled albumin (at a concentration similar to that of the pleural fluid) in the costal region of anesthetized dogs (n = 13) either breathing spontaneously or apneic. The decay rate of labeled activity at the injection site was studied with a gamma camera placed either in the anteroposterior (AP) or laterolateral (LL) projection. In breathing animals (respiratory frequency approximately 10 cycles/min), 10 min after the injection the activity decreased by approximately 50% on AP and approximately 20% on LL imaging; in apneic animals the corresponding decrease in activity was reduced to approximately 15 and approximately 3%, respectively. We considered label translocation from AP and LL imaging as a result of bulk flows of liquid along the costomediastinal and gravity-dependent direction, respectively. We related intrapleural flows to the hydraulic pressure gradients existing along these two directions and to the geometry of the pleural space. The pleural space was considered as a porous medium partially occupied by the mesh of microvilli protruding from mesothelial cells. Solution of the Kozeny-Carman equation for the observed flow velocities and pressure gradients yielded a mean hydraulic radius of the pathways followed by the liquid ranging from 2 to 4 microns. The hydraulic resistivity of the pleural space was estimated at approximately 8.5 x 10(5) dyn.s.cm-4, five orders of magnitude lower than that of interstitial tissue.
Authors:
G Miserocchi; D Venturoli; D Negrini; M C Gilardi; R Bellina
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  73     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1992 Dec 
Date Detail:
Created Date:  1993-02-26     Completed Date:  1993-02-26     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  2511-6     Citation Subset:  IM    
Affiliation:
Instituto di Fisiologia Umana, Università degli Studi, Ospedale San Raffaele, Milan, Italy.
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MeSH Terms
Descriptor/Qualifier:
Animals
Apnea / physiopathology
Body Fluids / physiology*
Dogs
Gamma Cameras
Microvilli / physiology
Models, Biological
Pleura / physiology*
Pressure

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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