A Comparative Study of Bupivacaine with Dexamethasone and Bupivacaine Alone Under Ultrasound Guided Supraclavicular Brachial Plexus Block for Post-Operative Analgesic Efficacy in Below Mid-Arm Orthopaedic Surgeries

Aim: comparing analgesic efficacy of dexamethasone as an adjuvant with bupivacaine under ultrasound guided supraclavicular brachial plexus block in patients undergoing below mid arm orthopedic surgeries.

Method: This prospective study comprised 60 patients in compliance with ASA physical study of class 1 and 2 provided for below mid arm orthopedic surgeries in patients attending preanesthetic checkup clinic of Nalanda Medical College and Hospital.

Results: One common regional nerve block method used in upper limb procedures is supraclavicular brachial plexus block. For brachial plexus block, local anaesthetics alone offer favorable operating conditions, but the duration of postoperative analgesia is shorter. To extend the duration of sensory block (analgesia), a variety of medications have been used in conjunction with local anaesthetics in brachial plexus block. Local anaesthetic & glucocorticoid perineural injection have been shown to affect the length & onset of sensory & motor block. In this regard, we chose to conduct a randomized, double-blind clinical trial to assess the impact of dexamethasone added to 0.25% bupivacaine in supraclavicular brachial plexus block on the length & commencement of sensory & motor block as well as the need for post-operative rescue analgesics. The study was carried out at Nalanda Medical College & Hospital's Department of Anaesthesiology. Two equal groups (groups A & B) of sixty adult patients with ASA grades I or II were assigned at random. They had a supraclavicular brachial plexus block & underwent a variety of orthopaedic procedures on their elbow, forearm, or hand. In groups A (dexamethasone group) & B (control group), supraclavicular brachial plexus block was carried out using 38 mL 0.25% bupivacaine with 2 mL dexamethasone & 38 mL 0.25% bupivacaine plus 2 mL 0.9% normal saline, respectively. Postoperative rescue analgesic requirement, duration of sensory & motor block, & onset time was compared between the two groups. The two groups' demographic characteristics & surgical time did not differ statistically significantly. Both groups saw identical onset times for sensory (dexamethasone group: 18.26 ± 1.25 min versus 18.70 ± 1.26 min) & motor block (dexamethasone group: 19.96 ± 1.28 min versus control group: 20.26 ± 1.28 min). The dexamethasone group experienced a significantly longer duration of sensory block (1091.11 ± 107.42 min versus 605.37 ± 58.60 min in the control group) & motor block (846.67 ± 102.09 min in the dexamethasone group versus 544.07 ± 55.40 min in the control group) than the control group (p value < 0.001). In the first 24 hours following surgery, patients in the dexamethasone group needed a considerably lower number of injections of diclofenac sodium than patients in the control group (p value < 0.001).

Conclusion: In supraclavicular brachial plexus block, we find that adding 8 mg dexamethasone to bupivacaine 0.25% solution prolongs the duration of sensory & motor blockade & decreases the need for a rescue analgesic in the postoperative period, but it has no effect on when sensory & motor blockade first occurs. The ideal dosage of dexamethasone for chronic brachial plexus block & the precise mechanism underlying this action require more research.