Effect of Intravenous Dexmedetomidine on Spinal Anaesthesia with Hyperbaric Bupivacine.

ABSTRACT

Background: Spinal anaesthesia is one of thecommonest anaesthetic techniques for infra-umbilicalsurgeries. Administration of dexmedetomidine forsedation during spinal anaesthesia is found to prolongthe duration of block. Aim and Objectives: To evaluating the effect of intravenous dexmedetomidine onblock characteristic of spinal anaesthesia withhyperbaric bupivacaine. Material and Methods: Atotalof 120 patients scheduled for various elective surgeriesunder spinal anaesthesia with hyperbaric bupivacainewere included in the study. The patients were dividedinto two groups of each containing 60 subjects. GroupD received 1µg/kg bolus dexmedetomidine over 10minutes immediately after spinal anaesthesia followedby 0.5µg/kg/hr infusion till the end of surgery andGroup S received similar amount of saline. Datacollected include onset of sensory and motor blockade,time for two segmental regression of block, duration ofanalgesia and sedation score were noted. Results:Onset of sensory block was faster in group D(2.38±1.48 min) as compared to Group S (3.03±0.22min). Onset of motor block was significantly faster inGroup D (6.97±0.93 min) as compared to Group S(8.01±0.85 min). Time required for two segmentregression was prolonged in Group D (122.67±7.15min) as compared to Group S (65.76±4.71 min). Totalduration of analgesia was also prolonged in group D(4.29 ±1.04 hr) compared to Group S (2.24±0.29 hr).Conclusion: Intravenous administration of dexmedetomidine prolongs the duration of sensory and motorblockade with arousable sedation.