Background and Aims: The addition of adjuvants to local anesthetic (LA) agents through epidural route helps in lower limb surgeries by providing postoperative analgesia. We attempted to establish whether addition of Dexmeditomidine to Bupivacaine infusion provides better analgesia and hemodynamic stability than Ketamine as an adjuvant.

Methods: The study involved sixty patients undergoing lower limb surgeries, using either Dexmeditomedine (Group D [n=30]) or Ketamine (Group K [n=30]) as adjuvant along with primary LA (0.5% hyperbaric Bupivacaine) through epidural route with CSE (combined spinal epidural). Primary outcome measure was the VAS (visual analogue scale). Receding time for motor blockade, level of sedation, duration of analgesia, effects on hemodynamic parameters were among the secondary outcome parameters.

Results: VAS became significantly lower at 6 hours (p=0.002) and 12 hours (p=0.007) in Group D than Group K. The receding time for motor blockade was significantly (p=0.0001) higher in Group D (6.19±0.87 hrs.) than Group K (4.71±0.91 hrs.). The total LA drug used was significantly (p=0.0001) higher in Group K (209.40±20.58 ml) than Group D (168.13±10.34 ml). The level of sedation was level I in 86.7% patients in Group D and in all the patients of Group K. The duration of analgesia was significantly higher in Group D (8.78±0.41 hrs.) than Group K (6.37±0.64 hrs.) (p=0.04). Mean Systolic Blood Pressure (SBP) (p=0.001) and Mean Heart Rate (HR) (p=0.001) in Group D were significantly lower than Group K at all the time periods.

Conclusion: We conclude that using Dexmedetomidine as an adjuvant to LA through epidural route provides better postoperative pain relief and also reduces the requirement of LA.

Keywords: Dexmeditomidine, Ketamine,Epidural Analgesia.

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Dr Kriti Singh

Batra Hospital and Medical Research Centre, New Delhi