Comparative study between dexamethasone and dexmedetomidine in supraclavicular block

Background: With the addition of adjuvants to local anaesthetics the onset, duration and quality of brachial plexus block improves to a marked extent. The intent of this study was to compare onset, duration of sensory and motor block along with duration of analgesia when an α-2 agonist dexmedetomidine or a steroid dexamethasone was added to a mixture of 2% lignocaine with adrenaline and 0.5% bupivacaine.Methods: 100 patients belonging to ASAI and ASAII were included in the study scheduled for upper limb surgeries after taking informed consent. These patients were divided in to two groups having 50 patients in each group. Group D received 20ml of 2% lignocaine with adrenaline plus 18ml of 0.5% bupivacaine plus 50μg of dexmedetomidine and group X received 20ml of 2% lignocaine with adrenaline plus 18ml of 0.5% bupivacaine plus 8mg of dexamethasone. Onset of sensory and motor block, duration of block, quality of intraoperative analgesia and duration of analgesia were recorded.Results: Our study revealed similar onset of sensory block in group D and X. Group D showed early onset and longer duration of motor block compared to group X. Intraoperative haemodynamics were similar in both groups.Conclusions: Our study concludes that using dexmedetomidine as adjuvant prolongs the duration of block and postoperative analgesia compared to dexamethasone with minimal or negligible adverse events.