A prospective randomized double blind study to find out the efficacy of dexmedetomidine 1μcg/kg single infusion as an adjuvant for general anaesthesia

Background: Dexmedetomidine is an α2-adrenoreceptor agonist with sedative, analgesic and anxiolytic effects. We evaluate the effect of preanaesthetic dexmedetomidine 1 μg/kg single infusion on sedation, haemodynamics, anaesthetic consumption, and recovery profiles during anaesthesia. Methods: Sixty patients of both gender with American Society of Anaesthesiologists physical status I or II undergoing surgery with anticipated operation time of 2 h, were randomly assigned to receive dexmedetomidine 1 μg/kg (study group) or normal saline (control group) intravenously over 10 min before anaesthetic induction. After tracheal intubation with Inj. thiopentone sodium 5 mg/kg intravenous (i.v.), vecuronium 0.12 mg/kg i.v., anaesthesia was maintained with sevoflurane, O2 50%, N2O 50% around a BIS value of 40. Results: After infusion of the study drug was completed, BIS of study group was significantly lower than that of control group (57.36±3.88 vs 96.66±1.51, p < 0.0001). After tracheal intubation, HR, SBP, DBP, MAP was significantly higher (p < 0.05) in control group than the study group. During maintenance, HR, SBP, DBP and MAP remained significantly lower (p < 0.05) in study group than control group. Sevoflurane consumption for 2 hours duration of surgery was significantly less in study group than control group (25.05±2.67 vs 33.14±3.70,p<0.0001). Patients in study group took significantly more time to respond to suction catheter, to obey verbal commands and for complete extubation than the control group (p < 0.05). Conclusion: Preanesthetic dexmetomidine 1 μg/kg single infusion is an economical and useful adjuvant to general anaesthesia that maintains stable haemodynamics, decrease anaesthetic consumption and provides good post-operative analgesia.