Linked Life Data

877860

Source:http://linkedlifedata.com/resource/pubmed/id/877860

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1977-8-25
pubmed:abstractText
The ability of the lung to decrease blood flow to an atelectatic lobe and to increase flow to normal after reinflation was investigated with a model using left lower lobe atelectasis (LLLA) in the dog. The change in the shunt fraction QS/Qt with continuing LLLA was assumed to represent a change in blood flow to the LLL. With LLLA the Qs/Qt rose from 0.112 to 0.172 and then decreased to 0.119 by the end of 2 hours at the rate of -17%/hour. Reversal of atelectasis for varying times demonstrated that the pulmonary vasoconstrictive response persisted for at least 4 hours after reinflation of LLLA. With LLL ischemia for 1 and 2 hours followed by LLLA, Qs/Qt decreased, but at a rate less than the controls, whereas after hemorrhagic shock with venous reinfusion and LLLA, the Qs/Qt did not decrease. When hemorrhagic shock was followed by arterial reinfusion, 60% had a normal response to LLLA; 40% did not. There was no difference in PVR in these two groups. Pulmonary extravascular water in both groups was the same as in controls. Infusion of NE after 3 hours of LLLA caused Qs/Qt to rise from 0.125 to 0.248, comparable to the value immediately after onset of LLLA. EPi had similar results. Catecholamines may restore blood flow to the atelectatic lobe by causing a maximum generalized pulmonary vasocontriction or by overexpansion of the pulmonary blood volume secondary to peripheral vasoconstriction and thereby abolish any differential in pulmonary vascular resistance across the lung. The early hypoxemia of adult respiratory distress syndrome may arise not on the basis of any intrinsic lung pathology but rather as the result of a normal response of the lung to increased catecholamines.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0039-6060
pubmed:author
pubmed:issnType
Print
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
90-8
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1977
pubmed:articleTitle
The nature of failure of pulmonary adaptation to atelectasis.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.