Aim: Intrathecal adjutants are being used to prolong the action of spinal anesthesia. Most of the studies have been conducted using intrathecal clonidine. This is a randomized clinical trial conducted to compare the effects of intravenous clonidine and dexmedetomidine on 0.5% bupivacaine in prolonging action of spinal anaesthesia.

Method: A prospective study of 120 patients undergoing lower limb and intra abdominal surgeries were divided into 3 groups: Group A — Received 0.9% saline infusion 20 minutes after spinal block. All patients received intravenous fluids as needed till the end of surgery. Group B — Received injection clonidine 2mcg/kg given as 20 minutes infusion started 20 minutes after spinal block and followed by a 0.9% saline drip till the end of surgery. Group C — Received an infusion of injection 1mcg/kg dexmedetomidine started 20 minutes after the spinal block and infused in 20 minutes, followed by 0.5mcg/kg/h dexmedetomidine drip till the end of surgery. Study was analyzed by Anova test. P value <0.05 was considered statistically significant.

Results: Patient demographics were comparable in all groups. Duration of sensory blockade was longer with group C (in minutes) (325.74± 10.59) than group B (270.41±11.98) and group A (222.54±15.03), p value 0.001. Duration of motor blockade was longer with group C (270.97± 6.15) than group B (243.67±9.22) & group A (208±12.83), p value (0.001). Duration of analgesia was longer with group C (366.13± 0.19) than group B (300±12.65) and group A (252.51±8.80), p value (0.001). Dexmedetomidine has more incidence of bradycardia and hypotension than other two groups but without any major clinical impact.

Conclusion: Intravenous dexmedetomidine and clonidine both prolongs action of spinal anaesthesia and postoperative analgesia than 0.5% hyperbaric bupivacaine. Dexmedetomidine has longer duration of action than Clonidine due to its alpha 2 receptor selectivity.

Keywords: Clonidine, Dexmedetomidine, Analgesia.

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Sharvari P. Jagadale

Senior Resident, Department of Anesthesia, R.C.S.M. Govt Medical College and CPR Hospital, Kolhapur

Flat no. 303, Junction 176 Apartment, Near Khanvilkar Petrol Pump, Nagala Park, Kolhapur, Maharashtra, 416003, India