Comparison between Dexmedetomidine and Buprenorphine as Adjuvants to Isobaric Levobupivacaine in Spinal Anaesthesia for Elective Lower Limb Surgeries

Abstract

Background: Levobupivacaine and racemic bupivacaine are equally effective in spinal anaesthesia with less systemic toxicity seen with levobupivacaine. Buprenorphine and Dexmedetomidine now being evaluated as a potential neuraxial adjuvant. This study has been designed to study various effects and any adverse effects of addition of either dexmedetomidine or buprenorphine to 2 ml of 0.5% isobaric levobupivacaine intrathecally for lower limb surgeries. Methods: In this randomized, double-blind prospective study, 60 patients of ASA I and II were randomized into two groups: group LD and LB (n=30). All patients received a drug volume of 2.5 ml containing 2 ml isobaric levobupivacaine (15 mg). They received dexmedetomidine 10 μg (Group LD) or 60 μg of buprenorphine (Group LB) diluted to 0.5 ml with distilled water added to levobupivacaine in the same syringe. Results: It was found that the onset of sensory block upto T10 and motor block is statistically significantly faster in group LD (109.33 and 153.5, in sec) over group LB (133 and 167.67, in sec). The mean time for two segment regression, the mean time to sensory regression to L1, the mean duration of analgesia and the mean duration of motor blockade is significantly prolonged in Group LD (106.67, 322, 343, 330.5, in min) over Group LB (132.67, 259.67, 290.67, 253.34, in min) with p<0.001. Conclusion: 10μg of dexmedetomidine added to local anaesthetic in subarachnoid block has proved to be a better adjuvant in prolonging the sensory and motor blockade intraoperatively and the duration of postoperative analgesia compared to 60μg of buprenorphine, without significant adverse effects. Keywords: Spinal anaesthesia; Levobupivacaine; Buprenorphine; Dexmedetomidine.