Objectives: To compare the effectiveness of inj. Dexamethasone 4mg added to 1.5% lignocaine with adrenaline with inj Dexamethasone 8mg added to 1.5% lignocaine with adrenaline in Supraclavicular Brachial Plexus Block in terms of onset of sensory and motor blockade andduration of sensory and motor blockade.

Materials and Methods: The study was carried out as a Prospective, randomized clinical trial among 150 patients who underwent different surgical procedures under supraclavicular brachial plexus block. They were randomized into three groups. GROUP A: Patients belonging to this group are given supraclavicular brachial plexus block with 4 mg dexamethasone as adjuvant to 1.5 %lignocaine with adrenaline (7mg/kg). GROUP B: Patients belonging to this group received supraclavicular brachial plexus block with 8 mg dexamethasone as adjuvant to 1.5 % lignocaine with adrenaline (7mg/kg). GROUP C: Patients belonging to this group received supraclavicular brachial plexus block with 2ml of normal saline added to 1.5 % lignocaine with adrenaline (7mg/kg). The three groups were compared with regard to onset of sensory and motor blockade andduration of sensory and motor blockade.

Results: No statistically significant difference was reported between the three groups in demographic variables. The mean time required for onset of sensory block in Group A and Group B is 11.2 minutes and in Group–C is 14.26, onset of motor block Group A and Group B is 13.0 minutes and in Group–C is 17.0 min. The average duration of sensory block in Group B>A>C. The average duration of Motor block in Group B is 242min, and in Group A with 192 min and with Group C is 153min.

Conclusion: In conclusion, addition of dexamethasone to local anaesthetics in supraclavicular brachial plexus block results in a faster onset and prolonged duration of sensory and motor blockade. Higher dose (8mg) of dexamethasone is more efficacious than lower dose (4mg) of dexamethasone as an adjuvant with local anaesthetics in terms of duration of sensory block, motor block and analgesia but equally efficacious in onset of sensory and motor blockade.