Context: Propofol is the commonly used intravenous drug to maintain adequate depth of anaesthesia in brachial plexus repair surgery under general anaesthesia without muscle relaxant. It has rapid onset of action, antiemetic effect and rapid emergence but causes respiratory and cardiac depression. Dexmedetomidine, an adrenergic agonist, with sedative, analgesic andanaesthetic sparing effects is an alternative intravenous drug to maintain depth of anaesthesia.

Aims: We designed a prospective study to see the effect of intravenous infusion of dexmedetomidine and propofol on haemodynamics, ionic balance and postop sedation in brachial plexus repair surgery under the guidance of entropy.

Methods: Fifty patients undergoing brachial plexus repair surgery were randomly divided into two groups of twenty five each. Group D group patients received 1μg/kg dexmedetomidine iv loading  dose for 10 min followed by infusion of 0.2 to 0.6 μg/kg/hr. Group P patients received propofol 1 mg/kg iv loading dose followed by infusion of 2 to 3 mg/kg/hr to maintain intraoperative entropy range from 40 to 60. Haemodynamics was noted at baseline, 1minute, 5 minutes, 10 minutes, 15 minutes, 30 minutes after intubation and later every 30 minutes till the end of the surgery. ABG was analysed at baseline, 2 hours after intubation and half hour before exbutaion Postop sedation score was noted immediate after extubation, 30 minutes and 60 minutes post extubation. Results: D group had significant lesser heart rate from the baseline. than P group. Systolic blood pressure, Diastolic blood pressure and Mean arterial pressure at 1 minute and 5 minutes after intubation, intraoperative state and response entropy were significantly lower than the baseline in P group than D group. P group also had more postop sedation score at extubation and 30 minutes post extubation than D group. ABG was maintained in the normal range, but P group had less pH, less Serum bicarbonate, and less base excess before extubation and less serum potassium 2 hours after intubation than D group. Other parameters of demographics, pO2, serum lactate, sodium, potassium and chloride were similar in both the groups. Conclusion: Intravenous Dexmedetomidine is an alternative adjuvant to propofol to maintain depth of anaesthesia for brachial plexus repair surgery with stable haemodynamics, blood gas towards normal range and low postop sedation scores.