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

Dr Mohin Georgee George, et al. 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. Int. J Med. Pharm. Res., 6 (5): 737‐738, 2025 737 International Journal of Medical and Pharmaceutical Research Online ISSN-2958-3683 | Print ISSN-2958-3675 Frequency: Bi-Monthly Available online on: https://ijmpr.in/ Research Article 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 Dr Mohin Georgee George1, Dr M Sweetline Subha2, Dr D Kannan3 1MBBS, DA, DNB, Dr Somervell Memorial CSI Medical College and Hospital, Thiruvananthapuram, Kerala, India 2MBBS, DA, DNB, Dr Somervell Memorial CSI Medical College and Hospital, Thiruvananthapuram, Kerala, India 3MBBS, DA, DNB, MMHRC, Madurai, Tamilnadu, India A B S T R A C T Corresponding Author: Dr Mohin Georgee George MBBS, DA, DNB, Assistant Professor, Department of Anaesthesiology, Dr Somervell Memorial CSI Medical College and Hospital, Karakonam, Thiruvananthapuram, Kerala, India Received: 16-08-2025 Accepted: 05-09-2025 Available online: 25-09-2025 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. Copyright © International Journal of Medical and Pharmaceutical Research Keywords: spinal anaesthesia, dexmedetomidine, clonidine, bupivacaine, lower abdominal surgery, α2-agonists. INTRODUCTION Spinal anaesthesia with bupivacaine provides reliable intraoperative anaesthesia but is limited by shorter postoperative analgesia. Intrathecal adjuvants have been evaluated to improve block duration and patient comfort. α2-adrenergic agonists, particularly clonidine and dexmedetomidine, have shown promise due to their sedative, analgesic, and opioid - sparing effects without significant respiratory depression. This study aimed to compare intrathecal clonidine (30 mcg) and dexmedetomidine (3 mcg) as adjuvants to bupivacaine in patients undergoing lower abdominal surgeries. MATERIALS AND METHODS Design: Prospective, randomized, comparative study. Population: 60 patients, ASA I–II, aged 18–65 years, scheduled for elective lower abdominal surgery. Groups: - Group C (n=30): Bupivacaine 12.5 mg + Clonidine 30 mcg - Group D (n=30): Bupivacaine 12.5 mg + Dexmedetomidine 3 mcg Dr Mohin Georgee George, et al. 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. Int. J Med. Pharm. Res., 6 (5): 737‐738, 2025 738 Assessments: - Onset of sensory block (T10 level) - Onset of motor block (Modified Bromage 3) - Duration of analgesia (time to first rescue analgesic, tramadol 50 mg IV) - Hemodynamic parameters (HR, MAP at intervals for 12h) - Complications (hypotension, bradycardia, sedation) Statistics: SPSS v20 used. Independent t-test, chi-square/Fisher’s exact test. p < 0.05 considered significant. RESULTS - Sensory block onset: 6.43 ± 2.87 min (clonidine) vs 6.04 ± 2.93 min (dexmedetomidine), p=0.600 - Motor block onset: 7.6 ± 2.85 min vs 7.02 ± 2.84 min, p=0.431 - Analgesia duration: 333.3 ± 94.0 min vs 367.7 ± 89.0 min, p=0.152 - Hemodynamics: HR and MAP trends comparable; occasional bradycardia/hypotension treated effectively. - Complications: None had excessive sedation; adverse events minimal and comparable. DISCUSSION Both adjuvants provided comparable efficacy with stable hemodynamics. Dexmedetomidine showed a trend toward longer analgesia, consistent with prior studies. Clonidine, however, remains a cost-effective option, especially in resource-limited settings. Importantly, both agents were free of major complications at low doses, supporting their role as opioid-sparing alternatives. CONCLUSION Dexmedetomidine (3 mcg) and clonidine (30 mcg) are safe and effective intrathecal adjuvants to bupivacaine in spinal anaesthesia for lower abdominal surgeries. Dexmedetomidine may offer marginal clinical benefit, while clonidine remains more economical. Further multicentre trials with larger sample sizes are warranted. REFERENCES 1. Sur D, Agarwal A, Chaudhary A, Bogra J, Singh P, Gupta R et al. A comparative study of different adjuncts to enhance the effects of intrathecal bupivacaine. Int J Res Med Sci. 2017;5(5):2046-52. 2. Verma D, Naithani U, Jain D, Singh A. Postoperative analgesic efficacy of intrathecal tramadol versus nalbuphine added to bupivacaine. J Evol Med Dent Sci. 2013;2(33):6196-6206. 3. Asano T, Dohi S, Ohta S, Shimonaka H, Iida H. Antinociception by α2-agonists in rat spinal cord. Anesth Analg. 2000;90(2):400-407. 4. Akhter M, Mir AW, Ahmad B, Ahmad F, Sidiq S, Shah AM et al. Dexmedetomidine as an adjunct to spinal anesthesia in urological procedures. Int J Contemp Med Res. 2017;4(1):154-158. 5. Jamliya RH, Vansola R, Shah B, Chauhan DL. Effect of clonidine with bupivacaine for spinal anaesthesia in lower limb surgery. Natl J Integr Res Med. 2012;3(1). 6. Sethi BS, Samuel M, Sreevastava D. Low-dose intrathecal clonidine as adjuvant. Indian J Anaesth. 2007;51(5):415-9. 7. Kaabachi O, Zarghouni A, Ouezini R, et al. Clonidine 1 mcg/kg as an adjuvant in adolescents. Anesth Analg. 2007;105(2):516-9. 8. Elia N, Culebras X, Mazza C, Schiffer E, Tramèr MR. Clonidine as intrathecal adjuvant: systematic review. Reg Anesth Pain Med. 2008;33(2):159-67. 9. Niemi L. Intrathecal clonidine with bupivacaine. Acta Anaesthesiol Scand. 1994;38:724 –8. 10. Patro SS, Deshmukh H, Ramani YR, Das G. Dexmedetomidine with bupivacaine in infraumbilical surgeries. J Clin Diagn Res. 2016;10(3):13-16. 11. Halder S, Das A, Mandal D, et al. Different doses of dexmedetomidine in spinal anaesthesia. J Clin Diagn Res. 2014;8(11):GC01. 12. Al-Mustafa MM, Abu-Halaweh SA, Aloweidi AS, et al. Dexmedetomidine added to spinal bupivacaine in urology. Saudi Med J. 2009;30(3):365-70. 13. Gupta R, Bogra J, Verma R, et al. Dexmedetomidine as intrathecal adjuvant. Indian J Anaesth. 2011;55:347 -51. 14. Kim JE, Kim NY, Lee HS. Intrathecal dexmedetomidine in elderly TURP patients. Biol Pharm Bull. 2013;36(6):959-65. 15. Kanazi GE, Aouad MT, Jabbour-Khoury SI, et al. Low-dose dexmedetomidine or clonidine with bupivacaine. Acta Anaesthesiol Scand. 2006;50:222-7. 16. Singh R, Shukla A. Intrathecal clonidine vs dexmedetomidine. Indian J Fundam Appl Life Sci. 2012;2:24 -33. 17. Anandani DN, Shelat SD, Vaniya J, Patel P. Intrathecal dexmedetomidine vs clonidine in gynecological surgery. Int J Basic Clin Pharmacol. 2015;4:1163-7. 18. Suthar O, Sethi P, Sharma UD. Dexmedetomidine vs clonidine as adjuvants. Anaesth Pain & Intensive Care. 2015;18(2):149-54. 19. Chandra G, Krishna S, Singh P. Intrathecal dexmedetomidine vs clonidine in lower limb fractures. Int Surg J. 2017;4(12):3833. 20. Ganesh M, Krishnamurthy D. Dexmedetomidine vs clonidine in abdominal surgeries. Anesth Essays Res. 2018;12(2):539– 545.