Comparison of Effectiveness between Dexamethasone and Clonidine as an Adjuvant to Bupivacaine for Ultrasound-Guided Supraclavicular Brachial Plexus Block in Patients undergoing Upper Limb Surgery

Abstract

Background: The supraclavicular brachial plexus (SBPB) block is widely used for upper limb surgeries. Adding adjuvants such as dexamethasone and clonidine to bupivacaine may enhance its efficacy. This study evaluates and compares these adjuvants in terms of improved peripheral nerve blocks by reducing the onset time, improving the efficacy of the block during surgery and extending postoperative analgesia block, postoperative analgesia. Objective: This study was designed for the evaluation of the effectiveness of dexamethasone versus clonidine as an adjuvant to bupivacaine for ultrasound-guided supraclavicular brachial plexus block in patients undergoing upper limb surgery. Materials and Methods: This randomized controlled trial was conducted on 75 adult patients undergoing upper limb surgeries at Dhaka Medical College Hospital. Patients were divided into three groups: Group A (bupivacaine + normal saline), Group B (bupivacaine + dexamethasone), and Group C (bupivacaine + clonidine). Outcomes assessed included onset and duration of sensory and motor block, time for first demand of analgesia and total consumptions of analgesics within 24 hours, haemodynamic parameters, adverse effects were observed among three groups. Data were analyzed using ANOVA and t-tests, with statistical significance set at p<0.05. Results: The demographic profiles were similar in three groups (p value >0.05).The time for complete sensory block was 23.6±3.1, 18.9±3.2 and 14.7±3.0 minutes and time for the onset of maximum motor level was 29.5±3.9, 23.5±3.1 and 20.8±2.4 minutes in Group A, B and C respectively. These are significantly less in clonidine (group C) group compared to normal saline (group A) and dexamethasone (group B) group (p<0.05). The Ramsey sedation score (RSS) was higher in group C in first eight hours during postoperative periods than two other groups which was also statistically significant (p value <0.05). The time to regression of sensory block was 242.1±16.57, 932.9±44.9 and 739.16 ±13.47 minutes and motor block was 175.6±17.5, 780.8±26.2 and 570.6 ±22.0 minutes in groups A, B and C respectively. It was significantly longer in group B than in other two groups which was statistically significant (p value <0.05). Similarly in comparison to other two groups, group B had significantly increased time for motor recovery (190.8±18.3, 810.6±25.8 and 600.6±24.9 minutes in groups A, B and C respectively  with p value <0.05). On the other hand, group B had significantly longer time for 1^st demand of analgesic (260.6±23.0, 975.2±29.0 and 760.8±25.5 minutes in groups A, B and C respectively), significantly decreased total analgesic requirements in 24 hours (232.8±15.5, 84.7±13.8 and 166.1±19.4 mg in groups A, B and C respectively) and also significantly decreased total anti-emetic requirement in 24 hours (11.8±0.3, 4.1±0.8 and 8.0±0.0 mg in groups A, B and C respectively with p value <0.05). All over adverse effects were significantly less in group B compared to group A and group C (p value <0.05). Conclusion: Dexamethasone is superior to clonidine as an adjuvant to bupivacaine in terms of prolonged analgesia and fewer side effects, making it a better choice for ultrasound-guided supraclavicular brachial plexus blocks.

J Enam Med Col 2023; 13(1): 10-21