Introduction: Combined Spinal-Epidural Anaesthesia (CSE) combines two techniques thereby providing greater efficacy & cost effectiveness. Dexmedetomidine is well suited for conscious sedation as patients can be quickly aroused on demand but it has also got many side effects, so its dose is a concern.

Objective: This study compared intraoperative sedation, hemodynamic stability and duration of analgesia between two different low doses of intravenous dexmedetomidine infusion in patients for abdominal hysterectomy.

Methodology: A total of 100 individuals between the age of 30 and 65 years of American Society of Anesthesiologists (ASA) physical status Classes I and II who underwent total abdominal hysterectomies were randomly allocated into two groups, comprising 50 patients in each group. Group -1 received 0.5% hyperbaric bupivacaine intrathecally and 0.6 mcg/kg loading dose of dexmedetomidine intravenously over 20 min followed by 0.3 mcg/kg/hr maintenance dose while Group-2 received 0.5% hyperbaric bupivacaine and 0.4mcg/kg loading over 20 min followed by 0.3mcg/kg/hr maintenance dose intrathecally. Patients were closely monitored for systolic, diastolic and mean blood pressure, pulse rate, SPO2 and Sedation score, every 2 minutes from starting of loading dose of dexmedetomidine till first 20 min followed by every 5 min till the end of surgery. Patients of both Groups were observer for VAS score 24 hours postoperatively.

Results: A dose of 0.6 mcg/kg dexmedetomidine was associated with more hypotension and sedation as compared to infusion in the dose of 0.4 mcg/kg/h, with reduction in post-operative analgesic requirements.

Conclusion: Lower dosage of dexmedetomidine (0.4ug/kg) can also provide appreciably good analgesia and sedation and is also devoid of significant side effects like bradycardia and vomiting.

Keywords: Spinal-Epidural Anaesthesia, low dose dexmedetomide, sedation, analgesia.

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Dr Bhagirath Bhambhu

Department of Anaesthesiology, S.P. Medical College and A.G. Hospitals, Bikaner (Rajasthan), India