| Blood flow switching among pulmonary capillaries is decreased during high hematocrit. | |
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MedLine Citation:
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PMID: 15247197 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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Pulmonary capillary perfusion within a single alveolar wall continually switches among segments, even when large-vessel hemodynamics are constant. The mechanism is unknown. We hypothesize that the continually varying size of plasma gaps between individual red blood cells affects the likelihood of capillary segment closure and the probability of cells changing directions at the next capillary junction. We assumed that an increase in hematocrit would decrease the average distance between red blood cells, thereby decreasing the switching at each capillary junction. To test this idea, we observed 26 individual alveolar capillary networks by using videomicroscopy of excised canine lung lobes that were perfused first at normal hematocrit (31-43%) and then at increased hematocrit (51-62%). The number of switches decreased by 38% during increased hematocrit (P < 0.01). These results support the idea that a substantial part of flow switching among pulmonary capillaries is caused by the particulate nature of blood passing through a complex network of tubes with continuously varying hematocrit. |
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Authors:
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William A Baumgartner; Amanda J Peterson; Robert G Presson; Nobuhiro Tanabe; Eric M Jaryszak; Wiltz W Wagner |
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Publication Detail:
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Type: In Vitro; Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: Journal of applied physiology (Bethesda, Md. : 1985) Volume: 97 ISSN: 8750-7587 ISO Abbreviation: J. Appl. Physiol. Publication Date: 2004 Aug |
Date Detail:
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Created Date: 2004-07-12 Completed Date: 2005-01-14 Revised Date: 2007-11-14 |
Medline Journal Info:
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Nlm Unique ID: 8502536 Medline TA: J Appl Physiol Country: United States |
Other Details:
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Languages: eng Pagination: 522-6 Citation Subset: IM |
Affiliation:
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Department of Anesthesia, Indiana University School of Medicine, 635 Barnhill Dr., Indianapolis, IN 46202-5120, USA. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Animals Blood Pressure / physiology Capillaries / physiology Dogs Hematocrit* Lung / blood supply* Male Perfusion Pulmonary Circulation / physiology* |
| Grant Support | |
ID/Acronym/Agency:
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HL-36033/HL/NHLBI NIH HHS |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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