Background : The purpose of our study was to evaluate the effect of the addition of Dexamethasone 8 mg to 0.5% Ropivacaine 30 ml on duration of  Interscalene Brachial Plexus  Block in shoulder and upper arm surgeries.

Methods:  In 60 patients scheduled for shoulder and upper arm surgeries that underwent nerve block , Block was performed with 0.5 % Ropivacaine 30 ml under the guidance of nerve stimulator. Patients were randomly allocated to receive the same volume ( 30 ml ) of 0.5 % Ropivacaine with 2 ml normal saline ( group R ) , Dexamethasone 8 mg ( 2 ml )  ( group RD ) as an adjuvant. A blind observer recorded vitals, onset and maximum time taken for sensory and motor blockade , duration of sensory and motor blockade , duration of analgesia , requirement of rescue analgesia ( inj Diclofenac  IM ) , any complication , quality of blockade, VAS score at 0, 15 min, 30 min, 60 min, 90 min, 120 min or till completion of surgery intraoperatively and at 1 hr, 2 hr,3 hr, 4 hr, 5 hr, 6 hr, 12 hr, 18 hr and 24 hr, 48 hr post operatively.

Results: All patients had successful interscalene brachial plexus block. There were significant difference in duration of sensory , motor blockade, analgesia and rescue analgesic requirement.

Conclusion: The addition of Dexamethasone 8 mg to 0.5 % Ropivacaine 30 ml in Interscalene Brachial Plexus  Block prolongs  the duration of post operative analgesia significantly  with significant prolongation in motor and sensory blockade and decrese in post operative analgesic requirement. There was not statistically significant difference in vitals, onset of sensory and motor blockade.