Dexmedetomidine as an adjuvant to hyperbaric spinal bupivacaineforinfra-umbilical procedures: a dose related study

ABSTRACT

Various adjuncts have been used with local anesthetics in spinal anesthesia to provide good quality of intra-operative and better post-operative analgesia. Dexmedetomidine is a new adrenergic agonist, now being used as a neuraxial adjuvant.The aim of our study was to investigate the effect of intrathecal administration of dexmedetomidine 5 umicrog and 10 microg, as an adjuvant to bupivacaine 0.5%, on the onset and duration of sensory and motor block, the hemodynamic effects, the duration of analgesia and the occurrence of side effects. This prospective randomized double blind study included 90 patients. Patients were randomly allocated into three groups of 30 patients each. Group B received 15 mg of 0.5% hyperbaric bupivacaine with normal saline, group Dl received 15 mg of hyperbaric bupivacaine with 5 jag and group D2 received 15 mg of hyperbaric bupivacaine with 10 ug of dexmedetomidine with normal saline to a total volume of 3.5 ml. The onset and duration of sensory and motor block, the hemodynamic effects, the duration of analgesia and the occurrence of side effects were noted. The mean time taken for the sensory block to reach T10 dermatome and motor block to reach Bromage 3 grade was significantly rapid in Dl and D2 groups as compared to bupivacaine group. The time taken for regression of sensory block to SI dermatome and Bromage 0 motor block and the time to first rescue analgesic were increased significantly by addition of dexmedetomidine in a dose dependent manner. Dexmedetomidine added to hyperbaric bupivacaine intrathecally has a dose dependent favorable effect on the onset and regression of sensory and motor block