Dexmedetomidine attenuates sympathoadrenal responses to tracheal intubation and reduces the need for thiopentone and peroperative fentanyl

Abstract

Summary: The effects of the new, highly selective alpha2-adrenergic agonist, dexmedetomidine, were studied in a randomized, placebo-controlled, double-blind trial in 24 ASA I patients. Dexmedetomidine 0.6 μg kg-1 or saline was given i.v. 10 min before induction of anaesthesia. The required dose of thiopentone was significantly (P < 0.001) smaller in the dexmedetomidine group (mean 4.4 (SD 0.9) mg kg-1) than in the control group (6.9 (1.6) mg kg-1), and the drug attenuated the cardiovascular responses to laryngoscopy and tracheal intubation. The concentration of noradrenaline in mixed venous plasma was smaller in the dexmedetomidine group during all phases of induction (P < 0.01). During surgery, fentanyl was required in a dose of 0.5 (0.6) mg kg-1 and2.8 (2.6) mg kg-1 in the dexmedetomidine and control groups, respectively (P < 0.001). During 2h postoperative follow-up, oxycodone 0.06 (0.06) mg kg-1 and 0.16 (0.1) mg kg-1 (P < 0.05) was given to the two groups respectively. © 1992 British Journal of Anaesthesia.