Randomized, double blinded clinical trial to evaluate efficacy of intrathecal clonidine and intrathecal morphine as adjuvants to hyperbaric bupivacaine in spinal anaesthesia for patients undergoing vaginal hysterectomy.

Healthy female patients, 18 years of age and older, who are undergoing vaginal hysterectomy under spinal anesthesia will be included in the study after IRB approval and CTRI registration. Patients will be informed about the anesthesia plan and will provide written informed consent a day before the surgery. Patients with contraindications for regional anesthesia will be excluded from the study. The participants will be randomly assigned to two groups. The control group will receive a subarachnoid block with heavy Bupivacaine 0.5% and intrathecal morphine 2 mcg/kg, according to the standard of care in our institution. Patients in the study group will receive a subarachnoid block with heavy Bupivacaine 0.5% and intrathecal clonidine 1 mcg/kg. Both groups will receive the same intraoperative monitoring of vital signs, IV fluids, and anti-emetic medications. The duration of analgesic effect will be measured from the time of spinal administration to the first analgesic request in the postoperative period. The time to regression of motor and sensory blocks will be assessed. Postoperative pain scores, side effects, time to first oral intake, and patient satisfaction scores will be recorded for both groups.