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Effects of thiopental on resistance vessels in cat skeletal muscle

Grände, P O LU ; Gustafsson, D and Lindberg, L LU (1990) In Intensive Care Medicine 16(6). p.399-404
Abstract

Barbiturates are used clinically as anaesthetics and to reduce raised intracranial pressure. One side effect is hypotension, usually ascribed to a depression of cardiac contractility, while their effects on the resistance vessels are more controversial: both vasodilation and vasoconstriction have been described. This study analyzes the effects of thiopental on basal vascular tone in the cat skeletal muscle. We found that total resistance increased by almost 20% at low (50 mumol/l) and decreased down to about 50% of control at high (350 mumol/l) plasma concentrations of thiopental. The vasoconstriction dominated in the large arterioles (i.d. greater than 25 microns) and the vasodilation in the small arterioles (i.d. less than 25... (More)

Barbiturates are used clinically as anaesthetics and to reduce raised intracranial pressure. One side effect is hypotension, usually ascribed to a depression of cardiac contractility, while their effects on the resistance vessels are more controversial: both vasodilation and vasoconstriction have been described. This study analyzes the effects of thiopental on basal vascular tone in the cat skeletal muscle. We found that total resistance increased by almost 20% at low (50 mumol/l) and decreased down to about 50% of control at high (350 mumol/l) plasma concentrations of thiopental. The vasoconstriction dominated in the large arterioles (i.d. greater than 25 microns) and the vasodilation in the small arterioles (i.d. less than 25 microns). A dose-dependent inhibition of myogenic vascular reactivity (here defined as the maximum resistance increase to a transient rise in transmural pressure) coincided with the vasodilation. Autoregulation of blood flow was depressed by thiopental. During vasoconstriction there was a net transcapillary fluid absorption and during vasodilation a net fluid filtration. The fluid movements could be ascribed to variations in capillary hydrostatic pressure. If applicable to the cerebral circulation these results suggest that thiopental at high plasma concentrations might induce, instead of reduce, interstitial brain oedema.

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organization
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Contribution to journal
publication status
published
subject
keywords
Animals, Blood Flow Velocity, Capillary Resistance, Cats, Dose-Response Relationship, Drug, Injections, Intra-Arterial, Muscle Tonus, Muscles, Thiopental, Vascular Resistance, Journal Article, Research Support, Non-U.S. Gov't
in
Intensive Care Medicine
volume
16
issue
6
pages
399 - 404
publisher
Springer
external identifiers
  • scopus:0025042436
ISSN
0342-4642
language
English
LU publication?
yes
id
6f780231-5096-42e9-b4de-1998e7d1365b
date added to LUP
2018-04-25 13:37:50
date last changed
2018-05-29 09:34:55
@article{6f780231-5096-42e9-b4de-1998e7d1365b,
  abstract     = {<p>Barbiturates are used clinically as anaesthetics and to reduce raised intracranial pressure. One side effect is hypotension, usually ascribed to a depression of cardiac contractility, while their effects on the resistance vessels are more controversial: both vasodilation and vasoconstriction have been described. This study analyzes the effects of thiopental on basal vascular tone in the cat skeletal muscle. We found that total resistance increased by almost 20% at low (50 mumol/l) and decreased down to about 50% of control at high (350 mumol/l) plasma concentrations of thiopental. The vasoconstriction dominated in the large arterioles (i.d. greater than 25 microns) and the vasodilation in the small arterioles (i.d. less than 25 microns). A dose-dependent inhibition of myogenic vascular reactivity (here defined as the maximum resistance increase to a transient rise in transmural pressure) coincided with the vasodilation. Autoregulation of blood flow was depressed by thiopental. During vasoconstriction there was a net transcapillary fluid absorption and during vasodilation a net fluid filtration. The fluid movements could be ascribed to variations in capillary hydrostatic pressure. If applicable to the cerebral circulation these results suggest that thiopental at high plasma concentrations might induce, instead of reduce, interstitial brain oedema.</p>},
  author       = {Grände, P O and Gustafsson, D and Lindberg, L},
  issn         = {0342-4642},
  keyword      = {Animals,Blood Flow Velocity,Capillary Resistance,Cats,Dose-Response Relationship, Drug,Injections, Intra-Arterial,Muscle Tonus,Muscles,Thiopental,Vascular Resistance,Journal Article,Research Support, Non-U.S. Gov't},
  language     = {eng},
  number       = {6},
  pages        = {399--404},
  publisher    = {Springer},
  series       = {Intensive Care Medicine},
  title        = {Effects of thiopental on resistance vessels in cat skeletal muscle},
  volume       = {16},
  year         = {1990},
}