The effects of perioperative dexmedetomidine infusion on hemodynamic, neuroendocrine and recovery parameters

Abstract

The aim of this study was to determine the effects of low and moderate doses of dexmedetomidine infusions by evaluating hemodynamic and neuroendocrine responses in patients undergoing elective transurethral surgery. Materials and Methods:Fifty patients were randomly allocated to receive 0.45 (Group 1) or 0.6 (Group 2) µg kg -1 hr -1 dexmedetomidine infusion 10 minutes before induction of anesthesia. Heart rate, blood pressures, ETCO 2 and peripheral oxygen saturation values and parameters of non-invasive cardiac output were monitored. Measurement times were baseline (I), after dexmedetomidine infusion (II), after thiopental induction (III), after intubation (IV) and at 10-minute intervals during desflurane anesthesia. Anesthesia (2L min -1 50% N 2 O+O 2 ) was maintained with 4-6% desflurane corresponding to a bispectral index (BIS) value of 40-60. Venous blood samples were collected prior to intubation (I), at the 30 th min intraoperatively (II) and after extubation (III) to determine plasma adrenaline and noradrenaline levels. Chi-square, Student's t-test and repeated measures of variance were used for statistical analysis.Results: Two different doses of dexmedetomidine infusion produced similar hemodynamic effects. The cardiovascular and neuroendocrine parameters were suppressed more in Group 2 than in Group 1.Conclusions: These findings suggest that intraoperative 0.45 and 0.6 µg kg -1 hr -1 doses of dexmedetomidine result in similar intubation, recovery and hemodynamic responses. Cardiovascular and neuroendocrine parameters were suppressed more by the moderate dose of dexmedetomidine.

Effect of dexmedetomidine infusion on hemodynamic responses in microsurgery of larynx

“…[ 15 16 ] Its anesthesia sparing,[ 16 17 18 ] opioid sparing action,[ 16 19 ] and blunting of exaggerated hemodynamic responses during surgery have also been documented. [ 20 ]…”

“…A transient increase in MBP was observed at 2 min of administration of dexmedetomidine infusion, which was followed by a fall probably due to the vasoconstriction effect of dexmedetomidine mediated by α2B receptors appearing before the central sympatholytic action. [ 13 14 20 21 ]…”

Brussels sedation scale when different doses of dexmedetomidine is used with propofol as an inducing agent

“…An author in his study reported a series of three cases where they used dexmedetomidine as a total intravenous anaesthetic agent. They administered dexmedetomidine as a loading dose of 1µg/kg followed by an infusion of 0.7 µg/kg/hour [7] . The infusion was increased to 5 µg/kg/hour for a period of five minutes to achieve adequate depth.…”