Linked Life Data

6816765

Source:http://linkedlifedata.com/resource/pubmed/id/6816765

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1983-2-14
pubmed:abstractText
The effect of local pulmonary blood flow control by local alveolar O2 tension on steady-state pulmonary gas exchange is analyzed with techniques derived from control theory. In a single homogeneous lung unit with normal inspired and mixed venous blood gas composition, the homeostatic effect on local ventilation-perfusion ratios (VA/Q) regulation occurs over a restricted range of VA/Q. The homeostatic effect is maximal at a moderately low VA/Q (about 0.4) due to the slope of the O2 dissociation curve. In a multicompartment lung with a lognormal distribution of VA/Q, regulation of arterial O2 tension varies with the extent of inhomogeneity. At mild degrees of inhomogeneity where local pulmonary blood flow (Q) control acts predominantly on the lower VA/Q of the Q distribution, the regulatory effect is best. At severe degrees of inhomogeneity where local Q control acts mainly on the higher VA/Q of the Q distribution, the regulatory effect is worse, and positive-feedback behavior may occur. Local Q control has the potential of reducing the deleterious effects of lung disease on pulmonary gas exchange particularly when it operates in association with other regulatory mechanisms.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0161-7567
pubmed:author
pubmed:issnType
Print
pubmed:volume
53
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1100-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Effect of local pulmonary blood flow control on gas exchange: theory.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't