Comparison of dexamethasone and midazolam in improving the efficacy of 0.5% bupivacaine in ultrasound guided supraclavicular brachial plexus block.

Abstract

Objectives: The objective of this study was to compare the additive effect of dexamethasone versus midazolam as an adjuvant to bupivacaine for the mean duration of onset of sensory block and duration of analgesia with ultrasound guided supraclavicular block. Study Design: Randomized control trail. Setting: Research was jointly conducted at Arif Memorial Hospital affiliated with Rashid Latif Medical College and KEMU/Mayo Hospital Lahore under the auspices of Department of Anesthesiology. Period: 01/02/2017 to 30/06/2017. Material & Methods: Involved 264 patients of either sex, aged between 20-60 years undergoing upper limb surgery under ultrasound guided supraclavicular brachial plexus block. After obtaining informed consent, patients were randomly allocated into two treatment groups. Along with 0.5% bupivacaine, patients in Group-I received dexamethasone while those in Group-II received midazolam. Outcome variables were mean time to onset of sensory block and mean duration of analgesia which were noted and compared among the groups. Results: The mean age of the patients was 38.90±11.92 years. There were 201 (76.1%) male and 63 (23.9%) female patients in the study group. Majority (79.2%) of the patients belonged to ASA Class-I followed by ASA Class-II (20.8%). Mean time to onset of sensory block was significantly shorter with dexamethasone (10.02±1.26 vs. 11.07±1.38 minutes; p<0.001) as compared to midazolam and this difference was significant across all age, gender and ASA groups. Mean duration of analgesia was also significantly longer with dexamethasone (19.11±1.32 vs. 13.07±1.43 hours; p<0.001) as compared to midazolam and this difference was also significant across all age, gender and ASA groups. Conclusion: Addition of dexamethasone to bupivacaine in ultrasound guided supraclavicular brachial plexus block resulted in early onset of sensory block (10.02±1.26 vs. 11.07±1.38 minutes; p<0.001) and longer duration of analgesia (19.11±1.32 vs. 13.07±1.43 hours; p<0.001) as compared to midazolam in patients undergoing upper limb surgery irrespective of patient’s age, gender and ASA status.