A comparative study of dexamethasone versus midazolam as adjuvant to 0.5% bupivacaine in ultrasound-guided supraclavicular brachial plexus block for upper-limb surgeries

Abstract

Background: Ultrasound has been effective in using low volume of local anesthetics for supraclavicular block. Steroids have been shown to increase the duration of local anesthetics. Aims and Objectives: In this study, we compare the efficacy of dexamethasone versus midazolam when added to bupivacaine in supraclavicular brachial plexus block for upper-limb surgeries with regard to the time of onset and duration of sensory and motor blockades, duration of analgesia, sedation, and hemodynamic parameters. Setting and Design: This is a prospective, randomized, double-blind study conducted on 60 patients belonging to the American Society of Anesthesiologists physical status classes 1 and 2, undergoing upper-limb surgeries under ultrasound-guided supraclavicular brachial plexus block. Materials and Methods: Sixty patients were divided into two groups of 30 each. Group dexamethasone (Group D) received bupivacaine 0.5% 18 mL + dexamethasone 4 mg + 1 mL normal saline. Group midazolam (Group M) received bupivacaine 0.5% 18 mL + 2 mg midazolam. We compared the onset and duration of sensory and motor blocks, hemodynamic variables, pain and sedation scores, and duration of analgesia. Statistical Analysis: The statistical software, namely SPSS 18.0 and R environment ver. 3.2.2, were used for the analysis of the data. P < 0.05 was considered statistically significant. Results: The onset of sensory and motor blocks was significantly faster in Group D compared to Group M. The duration of sensory and motor blockades and duration of analgesia showed a significant increase in Group D in comparison with Group M. Conclusion: Dexamethasone as an adjuvant hastens the onset and prolongs the duration of both sensory and motor blocks and reduces postoperative analgesic requirement when compared to midazolam.