Dexmedetomidine as an anaesthetic adjuvant in patients undergoing intracranial tumour surgery:: a double-blind, randomized and placebo-controlled study

Background. Dexmedetomidine (DEX) has been shown to provide good perioperative haemodynamic stability with decreased intraoperative opioid requirements. It may have neural protective effects, and thus may be a suitable anaesthetic adjuvant to neurosurgical anaesthesia. Methods. Fifty-four patients scheduled for elective surgery of supratentorial brain tumour were randomized to receive in a double-blind manner a continuous DEX infusion (plasma target concentration 0.2 or 0.4 ng ml(-1)) or placebo, beginning 20 min before anaesthesia and continuing until the start of skin closure. The DEX groups received fentanyl 2 mu g kg(-1) at the induction of anaesthesia and before the start of operation, the placebo group 4 mu g kg(-1), respectively. Anaesthesia was maintained with nitrous oxide in oxygen and isoflurane. Results. The median times from the termination of N2O to extubation were 6 (3-27), 3 (0-20) and 4 (0-13) min in placebo, DEX-0.2 and DEX-0.4 groups, respectively (P < 0.05 anova all-over effect). The median percentage of time points when systolic blood pressure was within more or less than 20% of the intraoperative mean was 72, 77 and 85, respectively (P < 0.01), DEX-0.4 group differed significantly from the other groups. DEX blunted the tachycardic response to intubation (P < 0.01) and the hypertensive response to extubation (P < 0.01). DEX-0.4 group differed in the heart rate variability from placebo (93 vs 82%, P < 0.01). Conclusions. DEX increased perioperative haemodynamic stability in patients undergoing brain tumour surgery. Compared with fentanyl, the trachea was intubated faster without respiratory depression.