Jigar Ashokkumar Rupareliya1, Rajesh Vitthalrao Nagmothe2
BACKGROUND
This was a prospective randomised double-blind study to compare the single bolus dose of I.V. dexmedetomidine (0.5 mcg/kg) diluted in 10 mL normal saline given slowly before spinal anaesthesia followed by continuous infusion of I.V. dexmedetomidine at the rate of 0.2 mcg/kg/hr. with only single bolus dose of I.V. dexmedetomidine (0.5 mcg/kg) diluted in 10 mL normal saline given slowly over 10 mins. before spinal anaesthesia to find out the better technique, which has all the desired effects like prolongation of sensory and motor block and prolong postoperative analgesia with minimal side effects like hypotension and bradycardia.
MATERIALS AND METHODS
60 elective surgical patients posted for below umbilical abdominal surgeries and lower limb surgeries with ASA grade I and II with age, weight and height between 20-70 years, 40-70 kg and 150 to 170 cm respectively were selected. Patient was randomly allotted in two group of 30 patients. Patients in both the groups received I.V. dexmedetomidine bolus at the rate of 0.5 mcg/kg diluted in 10 mL normal saline slowly over 10 mins. using infusion pump prior to spinal anaesthesia with 3 mL 0.5% bupivacaine. After spinal anaesthesia, patient in Group D received infusion of dexmedetomidine at the rate of 0.2 mcg/kg/hr. (100 mcg dexmedetomidine diluted in 50 mL normal saline, i.e. 2 mcg/mL) by infusion pump till the end of surgery. In Group N, patient received infusion of 50 mL normal saline at predetermined rate till end of surgery. The onset of sensory and motor block, duration of sensory and motor block, haemodynamic stability and quality of surgical anaesthesia, intraoperative complications, postoperative analgesia and side effects were recorded.
RESULTS
Our study concluded that I.V. supplementation of bolus followed by continuous infusion of Inj. Dexmedetomidine prolong the duration of sensory and motor block induced with spinal bupivacaine 0.5% hyperbaric. It provides the stable haemodynamic condition with satisfactory anaesthetic condition with significant decrease in the requirement of intraoperative supplementation of sedative and analgesic drugs. It prolongs the duration of analgesia and decreases early requirement of analgesic drugs and does not increase side effects like hypotension, bradycardia, nausea and vomiting, shivering, pruritus. It also provides satisfactory arousable sedation without causing respiratory depression.
CONCLUSIONS
I.V. bolus plus continuous infusion of Inj. Dexmedetomidine is better alternative to I.V. bolus dexmedetomidine for prolonging sensory block, motor block and duration of analgesia induced with intrathecal hyperbaric bupivacaine.
