Document Detail


Dependence of defibrillation threshold upon extracellular/intracellular K+ concentrations.
MedLine Citation:
PMID:  7359067     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The effect of increasing extracellular potassium concentration (Ko) upon electrical ventricular defibrillation threshold was investigated in pentobarbital anesthetized dogs treated with intravenous potassium chloride. Defibrillation threshold fell duirng potassium intoxication. The percent decrease in defibrillation threshold was linearly related to the logarithm of Ko and to the potassium equilibrium potential (Ek), calculated from measured extracellular and intracellular potassium concentrations of ventricular muscle. In dogs supported by left ventricular bypass in order to maintain the circulation during potassium intoxication, the values of Ko and Ek required for spontaneous, K+ induced defibrillation (electrical defibrillation threshold = zero) were 16.6 mEq/L and -46 mV compared to the normal values of 3.9 mEq/L and -84 mV. Changes in defibrillation threshold related to changes in Ek may be significant events in digitalis intoxication and in myocardial anoxia during prolonged fibrillation.
Authors:
C F Babbs; S J Whistler; G K Yim; W A Tacker; L A Geddes
Related Documents :
7987527 - The effects of lidocaine on the vulnerable period during ventricular fibrillation.
16982127 - Effects of compression depth and pre-shock pauses predict defibrillation failure during...
3677787 - A comparison of the antifibrillatory effect of midazolam and flunitrazepam in acute myo...
17947797 - Laminar arrangement of ventricular myocytes influences electrical behavior of the heart.
22297037 - Grace risk score predicts contrast-induced nephropathy in patients with acute coronary ...
16188597 - Mechanism and mapping of atrial arrhythmia in the modified fontan circulation.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of electrocardiology     Volume:  13     ISSN:  0022-0736     ISO Abbreviation:  J Electrocardiol     Publication Date:  1980  
Date Detail:
Created Date:  1980-05-14     Completed Date:  1980-05-14     Revised Date:  2009-11-11    
Medline Journal Info:
Nlm Unique ID:  0153605     Medline TA:  J Electrocardiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  73-8     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Arrhythmias, Cardiac / physiopathology
Digitalis Glycosides / poisoning
Dogs
Electric Countershock*
Extracellular Space / metabolism
Heart / drug effects,  physiopathology
Intracellular Fluid / metabolism
Membrane Potentials / drug effects
Models, Biological*
Myocardial Contraction* / drug effects
Myocardium / metabolism*
Potassium / metabolism*,  physiology,  poisoning
Potassium Chloride / pharmacology
Ventricular Fibrillation / metabolism,  therapy
Chemical
Reg. No./Substance:
0/Digitalis Glycosides; 7440-09-7/Potassium; 7447-40-7/Potassium Chloride

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Effects of verapamil on action potentials of Purkinje fibers.
Next Document:  Swallowing-induced paroxysmal supraventricular tachycardia.