These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Propofol and thiopental depression of myocardial contractility. A comparative study of mechanical and electrophysiologic effects in isolated guinea pig ventricular muscle. Author: Park WK, Lynch C. Journal: Anesth Analg; 1992 Mar; 74(3):395-405. PubMed ID: 1539821. Abstract: The purpose of the study was to compare the actions of propofol and thiopental on myocardial contractility and cellular electrophysiologic behavior. Isometric tension of isolated guinea pig right ventricular papillary muscle was studied in normal and 26 mM potassium Tyrode's solutions at various stimulation rates (after rest up to 3 Hz). Normal and slow action potentials were also recorded by conventional microelectrodes. Propofol (30, 100, and 300 microM) applied in the commercial 10% Intralipid emulsion caused dose-dependent depression of contractions at all stimulation rates, whereas Intralipid alone had no effect. Thiopental (10, 30, and 100 microM) caused depression similar to the threefold greater concentrations of propofol. Although neither drug altered the normal action potential (AP) amplitude or dV/dt max, thiopental (30 microM) increased AP duration. In the partially depolarized (26 mM potassium) beta-adrenergically stimulated myocardium, propofol and thiopental caused dose-dependent contractile depression similar to that in normal Tyrode's solution. Whereas propofol did not alter slow AP characteristics, 30-100 microM thiopental increased slow AP duration (consistent with decreased potassium conductance), and 100 microM thiopental depressed dV/dt max (consistent with decreased calcium channel ionic influx). Comparing the clinical plasma concentration ranges required for an equivalent anesthetic effect, propofol depresses myocardial contractility less than thiopental.[Abstract] [Full Text] [Related] [New Search]