Response of hypotensive dogs to dopamine hydrochloride and dobutamine hydrochloride during deep isoflurane anesthesia

Abstract

In isoflurane-anesthetized dogs, a guideline dose for dopamine of 7 microg/kg/min is suggested; dobutamine alone did not improve MAP. Data regarding cardiovascular and UrO effects indicated that the combination of dopamine and dobutamine did not provide greater benefit than use of dopamine alone in dogs.

Effects of dobutamine, dopamine, phenylephrine and noradrenaline on systemic haemodynamics and intestinal perfusion in isoflurane anaesthetised horses

“…Previous studies in horses report comparable changes in systemic cardiovascular parameters . Studies on dogs using similar doses found significant increases in CO and SV , while a dose of 14 μg/kg bwt/min led to a marked increase in SVR . We did not use higher doses due to the risk of severe cardiac arrhythmias in horses reported with doses up to 10 μg/kg bwt/min .…”

What is the definition of intraoperative hypotension in dogs? Results from a survey of diplomates of the ACVAA and ECVAA

“…Arguably, the variable etiologies of hypotension limit the utility of such guidelines, despite literature relating to management strategies for hypotension (Rosati et al. ).…”

Catecholamines

“…Dopamine has been reported to increase renal blood flow at dosages of less than 5 mcg/kg/min (and to decrease it to baseline at 10 mcg/kg/min) and may increase urine output, 1-3 but dopamine therapy does not appear to provide any low-dose renal-protective efficacy in people. 4,5 When administered to critically ill people, 6 septic dogs 7 (in the author's experience), anesthetized dogs, [8][9][10] and anesthetized cats, 11 dopamine generally causes a modest vasoconstriction and increase in blood pressure with little change or modest increases in cardiac output. In one study of anesthetized cats, 12 dopamine was associated with vasodilation and increases in heart rate, cardiac output, and blood pressure.…”

“…When dobutamine is given to critically ill humans, 6,13 septic dogs 7 (in the author's experience), anesthetized dogs, [8][9][10]14 anesthetized cats, 12,15 and anesthetized foals, 16,17 it generally causes modest vasodilation and a marked increase in cardiac output with little change in blood pressure.…”

“…Adding dobutamine to dopamine (rather than simply doubling the dose of dopamine) would be expected to further increase contractility and relieve some of the vasoconstriction. 10 The addition of norepinephrine or phenylephrine or vasopressin to dobutamine or dopamine generally increases systemic vascular resistance and blood pressure. 43 One part dopamine and one part norepinephrine would be expected to provide better blood pressure support and fewer arrhythmogenic side effects than two parts of dopamine and better inotropic support than two parts of norepinephrine.…”