Linked Life Data

6735809

Source:http://linkedlifedata.com/resource/pubmed/id/6735809

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1984-8-23
pubmed:abstractText
Species with collateral ventilation have an auxiliary respiratory mechanism that could protect them, under certain circumstances, from regional alveolar hypoxia. Species without collateral ventilation may have a greater potential for routinely experiencing regional hypoxia; to maintain ventilation-perfusion balance they would have to rely on pulmonary vasoconstriction. We tested these ideas by ventilating a sublobar region of pig lung (no collateral ventilation) with 13% O2 while the rest of the lung was ventilated with 30% O2. Blood flow, as measured by radioactive microsphere distribution to the sublobar region, was reduced 50% during hypoxia. The hypoxia-induced vasoconstriction effectively defended arterial PO2. When a vasodilator was infused, regional blood flow increased to control levels; shunt fraction rose, and arterial PO2 fell. In dogs (collateral ventilation present) the same experimental maneuvers had no significant effect on regional end-tidal gases or on microsphere distribution, indicating that collateral ventilation was able to maintain ventilation-perfusion balance. When regional hypoxia was created in dogs by overcoming collateral ventilation with slightly positive airway pressure in the sublobar region, the dog acted like the pig and used hypoxic vasoconstriction to shift approximately 30% of the blood flow away from the hypoxic alveoli.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0161-7567
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1500-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Role of collateral ventilation in ventilation-perfusion balance.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.