Linked Life Data

1736703

Source:http://linkedlifedata.com/resource/pubmed/id/1736703

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1992-3-12
pubmed:abstractText
We investigated the effects of clinically administered volatile anesthetics and of adenosine on the microvasculature of the in situ beating canine heart. Thirteen dogs were studied during general anesthesia with an opioid (piritramide), which was infused throughout the experiments. Measurements were obtained in each animal at control (piritramide only) and during hypotension (mean arterial pressure 60 mmHg) induced by halothane, enflurane, isoflurane, and adenosine. Using epiillumination and fluorescence microscopy, 354 arterial microvessels with diameters from 20 to 450 microns were examined through all experimental periods. Hypotension by halothane, enflurane, isoflurane, and adenosine reduced coronary vascular resistance by 13%, 23%, 40%, and 85%, respectively. Coronary venous PO2 was unchanged from control with halothane (+/- 0%) and enflurane (+7%) and significantly increased with isoflurane (+16%) and adenosine (+65%). Left ventricular blood flow decreased significantly during halothane (-35%) and enflurane (-23%); was unchanged from control during isoflurane (-9%); but significantly increased during adenosine (+397%). Coronary arterial and arteriolar diameters increased with all hypotensive agents. Vasodilation was least with halothane, intermediate with enflurane and isoflurane, and most pronounced with adenosine. Diameters increased considerably more in vessels with initial diameters below 100 microns as opposed to larger vessels. Calculation of microvascular segmental resistances revealed that the maximum conductance changes during volatile anesthetics were located in the vessel segments visualized by microscopy, i.e., in vessels larger than 20 microns. However, this was not the case with adenosine. We conclude that volatile anesthetics induce coronary vasodilation by preferentially acting on vessels with diameters from 20 microns to approximately 200 microns, whereas adenosine, in addition, has a pronounced impact on the small precapillary arterioles.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0003-3022
pubmed:author
pubmed:issnType
Print
pubmed:volume
76
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
261-70
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Coronary microcirculation during halothane, enflurane, isoflurane, and adenosine in dogs.
pubmed:affiliation
Institute of Anesthesiology, University of Munich, Bavaria, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't