To Compare the Effects of Dexmedetomidine and Clonidine as An Adjuvant to Intrathecal Bupivacaine in Spinal Anaesthesia for Lower Abdominal Surgeries: A Prospective Comparative Study

Background: α2-adrenergic agonists such as clonidine and dexmedetomidine have been used as intrathecal adjuvants to bupivacaine to enhance block quality and prolong postoperative analgesia. Aim: To compare the efficacy of dexmedetomidine versus clonidine as adjuvants to hyperbaric bupivacaine in spinal anaesthesia for lower abdominal surgeries. Methods: Sixty ASA I–II patients aged 18–65 years undergoing elective lower abdominal surgeries were randomized into two groups (n=30 each). Group C received clonidine 30 mcg with 12.5 mg hyperbaric bupivacaine; Group D received dexmedetomidine 3 mcg with 12.5 mg hyperbaric bupivacaine. Block characteristics, duration of analgesia, hemodynamic parameters, and complications were assessed. Results: Demographics were comparable between groups. Mean sensory block onset was 6.43 ± 2.87 min (clonidine) vs 6.04 ± 2.93 min (dexmedetomidine, p=0.600). Motor block onset was 7.6 ± 2.85 min vs 7.02 ± 2.84 min (p=0.431). Analgesia duration was 333.3 ± 94.0 min vs 367.7 ± 89.0 min (p=0.152). Hemodynamic changes and side effects (hypotension, bradycardia) were minimal and not significantly different. Conclusion: Both clonidine 30 mcg and dexmedetomidine 3 mcg as intrathecal adjuvants provide effective block characteristics and stable hemodynamics. Dexmedetomidine showed a non-significant trend toward earlier onset and prolonged analgesia, while clonidine remains more cost-effective.