Background: Introduction-Intravenous regional anesthesia (IVRA) is a simple,reliable and cost effective technique for surgeries involving the distal arm.It has the advantage of speed of onset,rapid recovery, reliability of blockade and cost effectiveness. Various adjuvants have been added to local anesthetics to increase the speed of onset and duration of post operative analgesia.The aim of the present study is to compare the effects of adding fentanyl versus dexmedetomidine to lignocaine during IVR.

Materials and Methods: This study included 60 patients of ASA class 1 and 2 of either sex aged between 20-50 years scheduled for various  upper limb  surgeries.Patients were randomly divided in to two groups of 30 each.Group LF received 40ml of 0.5% lignocaine with fentanyl 2µg/kg and group LD received 40ml of 0.5% lignocaine with dexmedetomidine 1µg/kg. Postoperative pain score was recorded using Visual Analogue Scale (VAS). Injection paracetamol 1gram intravenous infusion was given as rescue analgesic when VAS score reached >4. Duration of postoperative analgesia was noted from deflation of torniquet to VAS score of 4. Patients were observed for adverse effects like skin rash,bradycardia and sedation intraoperatively and postoperatively following torniquet deflation in both the groups.

Result: Earlier onset time of both sensory block  (4.80±0.60min)and motor block (8.60±3.20min)were noted in group LD compared to sensory block(6.82±1.50min)and motor block (10.80±1.20min)in group LF.Postoperative analgesia was also considerably prolonged in group LD(350.52±42.5min)compared to group LF(204.42±32.5min). Adverse effects like bradycardia and sedation were noted in two and four number of patients respectively in group LD.

Conclusion: The addition of 1µg/kg dexmedetomidine to lignocaine when compared to 2µg/kg fentanyl in IVRA  reduces the time for onset of block, increases the duration of block. Improves quality of anarsthesia prolonged post operative analgesia and reduced rescue analgesia requirement.