HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Arrhythmogenic potential of dopexamine hydrochloride during halothane anaesthesia in dogs.

Abstract
Dopexamine hydrochloride (Dopacard) is the novel synthetic catecholamine designed for use in the acute management of a low cardiac output status. In addition to dopaminergic receptor stimulation, dopexamine hydrochloride is a potent beta 2 adrenoceptor agonist with negligible direct beta 1 and no alpha adrenergic effect. The objective of this study was to compare the arrhythmogenic effects of dopexamine hydrochloride and dopamine in dogs anaesthetized with halothane (1.2 MAC). The starting dose for dopexamine hydrochloride was 3.5 micrograms.kg-1.min-1 and for dopamine was 5 micrograms.kg-1.min-1. Concentrations of the drugs were increased until four or more premature ventricular contractions within 15 seconds were produced. All dogs developed ventricular tachycardia when dopamine was administered in concentrations ranging between 18-20 micrograms.kg-1.min-1. Unlike dopamine, dopexamine hydrochloride even at concentrations as high as 50 micrograms.kg-1.min-1 did not induce any atrial or ventricular ectopic beats. Lack of beta 1 and alpha adrenergic agonist effects is a likely explanation for low arrhythmogenicity of dopexamine hydrochloride. Both drugs increase cardiac output; dopexamine hydrochloride primarily by a dose-related increase in heart rate and increased afterload. At the maximal concentration dopexamine hydrochloride increased heart rate from 114 to 150 beat.min-1, mean arterial pressure decreased from 81 mmHg to 45 mmHg and SVR decreased from 2418 to 962 dyne.sec-1cm-5. Myocardial contractility increased only moderately, as evaluated by dP/dt, which increased from 1290 to 1696 mmHg.sec-1. Dopamine had a more marked inotropic effect: the dP/dt increased, at the maximal concentration, from 1480 to 2570 mmHg.sec-1.(ABSTRACT TRUNCATED AT 250 WORDS)
AuthorsS M Neustein, I Dimich, I Sampson, A Sadeghi, C Mezrow, H Shiang
JournalCanadian journal of anaesthesia = Journal canadien d'anesthesie (Can J Anaesth) Vol. 41 Issue 6 Pg. 542-6 (Jun 1994) ISSN: 0832-610X [Print] United States
PMID7915210 (Publication Type: Comparative Study, Journal Article)
Chemical References
  • Adrenergic beta-Agonists
  • Dopamine Agents
  • dopexamine
  • Halothane
  • Dopamine
Topics
  • Adrenergic beta-Agonists (administration & dosage, pharmacology)
  • Anesthesia, Inhalation
  • Animals
  • Arrhythmias, Cardiac (chemically induced)
  • Blood Pressure (drug effects)
  • Cardiac Output (drug effects)
  • Dogs
  • Dopamine (administration & dosage, analogs & derivatives, pharmacology)
  • Dopamine Agents (administration & dosage, pharmacology)
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Female
  • Halothane (administration & dosage)
  • Heart Rate (drug effects)
  • Male
  • Myocardial Contraction (drug effects)
  • Tachycardia, Ventricular (chemically induced)
  • Vascular Resistance (drug effects)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: