Background: Spinal anaesthesia using local anaesthetics produces profound sensory and motor blockade by interrupting neural transmission at the spinal level; however, the limited duration of action remains a clinical limitation. To enhance the quality and prolong the duration of spinal anaesthesia, various adjuvant agents have been used intrathecally. Clonidine, an α₂-adrenergic agonist, has been shown to augment neuraxial blockade and extend postoperative analgesia. The present study was undertaken to evaluate the effects of intrathecal clonidine added to 0.5% hyperbaric bupivacaine in patients undergoing vaginal hysterectomy under spinal anaesthesia. Materials and Methods: This prospective, randomized, double-blind, controlled, single-centre study was conducted at Sree Mookambika Institute of Medical Sciences, Kulasekharam, Tamil Nadu. Forty normotensive patients aged 45–65 years, classified as American Society of Anesthesiologists (ASA) physical status I and II, scheduled for elective vaginal hysterectomy were included. Patients received spinal anaesthesia with 0.5% hyperbaric bupivacaine combined with intrathecal clonidine. The onset and duration of sensory and motor blockade, duration of postoperative analgesia, hemodynamic parameters, visual analogue scale (VAS) scores, requirement of rescue analgesia, and adverse effects were recorded and analysed. Results: The mean time to achieve peak sensory blockade was 5.45 ± 0.50 minutes, while the onset of motor blockade occurred at 7.05 ± 0.22 minutes. The mean duration of sensory block was 189.80 ± 6.49 minutes and motor block lasted for 247.28 ± 8.42 minutes. The average duration of effective postoperative analgesia was 495.93 ± 22.43 minutes, with most patients requiring three doses of rescue analgesics during the first 24 hours. VAS scores remained at zero for the initial 4 postoperative hours and were below 5 at subsequent assessment intervals up to 24 hours. Hemodynamic parameters remained stable, with bradycardia observed in one patient and hypotension in two patients; all adverse events were mild and managed successfully. The overall incidence of side effects was minimal. Conclusion: Intrathecal clonidine, when used as an adjuvant to 0.5% hyperbaric bupivacaine, significantly prolongs the duration of spinal anaesthesia and postoperative analgesia with minimal side effects. Its use reduces analgesic requirements and enhances the quality of spinal anaesthesia, making it a valuable adjunct for vaginal hysterectomy procedures.

Clonidine; intrathecal adjuvant; hyperbaric bupivacaine; spinal anaesthesia; vaginal hysterectomy