A comparative study of 0.5% ropivacaine versus 0.5% ropivacaine with dexamethasone on postoperative pain in interscalene brachial plexus block for shoulder surgery

Post-operative pain after any shoulder surgery is very common. Pain management after shoulder surgeries pose a challenge to anesthesiologists. The study aims to assess the effect of dexamethasone as an adjuvant to 0.5% ropivacaine in ultrasound guided single shot interscalene brachial plexus block in elective shoulder surgeries. The prospective randomized comparative study was conducted at the Department of Anaesthesiology, Apollo Hospitals, Chennai, from March 2018 to December 2019. The study involved 52 patients scheduled for elective shoulder surgeries, who were randomly assigned to two groups: one receiving 0.5% ropivacaine alone and the other receiving 0.5% ropivacaine with dexamethasone, administered via ultrasound-guided interscalene brachial plexus block. Patient's perception of pain was assessed using VAS score (0-10). The mean duration of analgesia was significantly longer in the ropivacaine with dexamethasone group (909.5 ± 238.122 minutes) compared to the ropivacaine alone group (509.31 ± 102.771 minutes), with a mean difference of 400.192 minutes. Visual Analog Scale (VAS) scores for pain were comparable between the groups in the early postoperative period but were significantly lower in the dexamethasone group at 8, 10, and 12 hours post-surgery, indicating better pain control. The dexamethasone group also required significantly fewer additional analgesics. The study concluded that the addition of dexamethasone to ropivacaine for interscalene brachial plexus block prolongs the duration of analgesia and reduces post-operative pain, without significant complications. The use of dexamethasone as an adjuvant to local anesthetics for nerve blocks is recommended due to its safety profile, cost-effectiveness, and improved quality of pain relief.