Sympathoneuronal and sympathoadrenal activation during ketamine anesthesia

Abstract

The effects of ketamine anesthesia (3 mg/kg i.v.) on cardiovascular parameters and noradrenaline, adrenaline and dopamine-beta-hydroxylase (DBH) activity in plasma were studied in 12 patients. At 3, 6 and 10 min after induction of anesthesia, a pronounced increase in heart rate (+28%) and in systolic and diastolic blood pressure (+28% and 17% resp.) was observed. Concomitantly noradrenaline and adrenaline concentrations increased significantly from 187 to 415 ng/l and from 97 to 271 ng/l, respectively. DBH-activity in plasma remained almost unchanged. From these results it can be concluded that the well known cardiovascular stimulant effect of ketamine is due to greatly enhanced sympatho-neuronal and sympatho-adrenal activity, presumably brought about by a central mechanism of action of the drug. Furthermore, DBH-activity in plasma appeared not to be a reliable index of sympathetic activity in man.

Minimum alveolar concentration of isoflurane in dogs administered a single intramuscular injection of racemic or S (+)-ketamine after premedication with acepromazine-morphine

“…In man, this cardiovascular stimulating effect of ketamine was mainly attributable to sympathetic stimulation via a central mechanism resulting in increased circulating levels of norepinephrine and epinephrine (APPEL et al, 1979). Despite the expected cardiovascular stimulating effects of ketamine, bradycardia was observed in 23 to 30% of dogs and hypotension was observed in 70 to 77% of dogs in the present study.…”

Effects of anaesthesia induction drugs on circulation in denervated intestinal loop preparation

“…It was been shown that ketamine releases epinephrine and norepinephrine. [45][46][47][48] It is interesting to note that a substantial vasoconstriction in the intestines was observed for at least 45 minutes after ketamine injection. It has been shown that an increase in blood pressure, cardiac output, and heart rate with a concomitant increase in epinephrine and norepinephrine plasma concentrations usually do not last more than 10 to 20 minutes after ketamine injection.…”

Einsatz von Ketamin bei Sepsis und systemischen Entzündungsreaktionen

“…Ketamin besitzt einen zentralen sympathikomimetischen Effekt [32], der zu gesteigerten Serumspiegeln von Adrenalin und Noradrenalin führt [4,9,18] [39]. Obwohl in In-vitro-Untersuchungen nachgewiesen wurde, dass Ketamin einen dosisabhängigen direkten negativ inotropen Effekt ausübt [22,38], überwiegt in vivo offenbar die sympathische Stimulation, sodass Ketamin Anstiege von HF, MAD, SV und HZV bewirkt [4,9,19].…”