Effectiveness of Dexamethasone as an Adjuvant to Bupivacaine in Supraclavicular Brachial Plexus Block

Supraclavicular Brachial Plexus block is a simple and effective technique of providing anesthesia for elbow, forearm and hand surgery. This study investigated the onset of sensory and motor blockade and duration of analgesia after addition of dexamethasone with bupivacaine in supraclavicular brachial plexus block. An observational, comparative study was performed at Bir Hospital and National Trauma Center, Kathmandu. Forty patients undergoing surgery of elbow, forearm and hand under Supraclavicular Brachial Plexus Block, with 0.25% bupivacaine with dexamethasone (n = 20) in group I versus 0.25% bupivacaine with normal saline (n = 20) in group II with equal volume of 30 ml in each group. Randomization was done with lottery system using sealed envelope. Onset of sensory and motor blockade and duration of analgesia was compared in both the groups. The rescue analgesia injection diclofenac 75 mg was given if Visual Analogue Score was five or more. Each patient was assessed postoperatively by a blinded investigator at regular intervals of 15 minutes in first hour, 30 minutes in next hour and then hourly till the time to first rescue analgesia. SPSS version 24.0 software was used. Continuous variables like onset of sensory and motor block and time to first rescue analgesia was assessed with student’s t-test and Chi square test was applied to asses categorical variable like VAS score. The time to onset of sensory block in bupivacaine only group (505.50±72.52) seconds compared to bupivacaine with dexamethasone group (249.75±78.36) seconds. Time to onset of motor block in bupivacaine only group (792.00±89.94) seconds compared to bupivacaine with dexamethasone group (506.25±94.35) seconds. Time to first rescue analgesia in bupivacaine only group (537.00±162.25) minutes compared to bupivacaine with dexamethasone group (1371.00±282.95) minutes. Time to onset of sensory and motor block was significantly faster and duration of analgesia was significantly prolonged in bupivacaine with dexamethasone group compared to bupivacaine only group in patient undergoing surgery of arm, forearm, and hand surgery under supraclavicular brachial plexus block.