Comparative Evaluation of Intrathecal Use of two Different Doses of Dexmedetomidine Along with Bupivacaine in Lower Abdominal Surgeries

Abstract

Introduction: The addition of adjuvants to local anaesthetics in spinal anaesthesia avoids intraoperative somatic and visceral pain and provides prolonged post operative analgesia. Aim –The present study was designed to determine the dose related effects of intrathecal dexmedetomidine added as adjuvant to 0.5% hyperbaric bupivacaine on block characteristics, haemodynamics and analgesia potentiating effects. Patients and method –This prospective randomised double blind study included 90 patients undergoing lower abdominal surgeries, who were randomly allocated into three groups of 30 patients each. Group B received 12.5 mg of 0.5% hyperbaric bupivacaine intrathecally, group D5 received 12.5 mg of 0.5% hyperbaric bupivacaine and 5 µg of dexmedetomidine, group D10 was given 12.5 mg of 0.5% hyperbaric bupivacaine and 10 µg of dexmedetomidine, all three made upto a total volume of 3 ml with NS. The three groups were compared with respect to haemodynamic parameters, onset and regression of motor and sensory block, duration of analgesia, doses of rescue analgesia required and 24 hours complications. The mean time of onset of sensory block to T10 was (in minutes) group B 11.6±1.12, group D5 5.84±2.02, group D10- 4.92±1.23 (p <0.001). Total duration of sensory block was (in minutes) group B 172.61±24.68, group D5 268.34±28.42, group D10 346.28±44.8 (p <0.001). Total duration of motor block (in minutes) group B 150.66±18.64, group D5 268.44±24.85, group D10 322.9±49.68 (p <0.001). Duration of analgesia (in minutes) - group B 124.01±8.552, group D5 194.68±18.44, group D10 290.48±20.64 (p <0.001). Conclusion: dexmedetomidine added to hyperbaric bupivacaine intrathecally has a dose dependent favourable effect on the onset and regression of motor and sensory block.