title: Impaired effect of dopamine on cardiac output during octopamine infusion.
abstract: The hemodynamic effects of octopamine (OCT) were studied before and during dopamine (DA) infusion in six normal dogs. Before OCT infusion, DA significantly increased cardiac index (CI) from 3.24 +/- 0.20 to 4.90 +/- 0.30 L/min X m2 and significantly decreased systemic vascular resistance index (SVRI) from 3700.2 +/- 212.5 to 2618.3 +/- 156.6 dyne X sec/cm5 X m2, without changing heart rate. During OCT infusion, DA failed to increase CI or decrease SVRI; however, it significantly increased heart rate from 153.3 +/- 12.9 to 183.0 +/- 17.0 beat/min. This suppression of a DA-related increase in cardiac output may explain why DA is ineffective in those septic patients with elevated plasma OCT levels.
authors.forename: K
authors.initials: K
authors.lastname: Tajimi
authors.forename: I
authors.initials: I
authors.lastname: Kosugi
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002245:Carbon Dioxide / Q000097:blood; D002302:Cardiac Output / Q000187:drug effects*; D004285:Dogs; D004298:Dopamine / Q000494:pharmacology*; D004347:Drug Interactions; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007263:Infusions, Parenteral; D008297:Male; D009655:Octopamine / Q000494:pharmacology*
chemical_list: D002245:Carbon Dioxide; D009655:Octopamine; D004298:Dopamine