ABSTRACT
Background: To determine the effective volume of a combination of bupivacaine and lignocaine for supraclavicular achial plexus block using ultrasonography (USG). Methods: This study is an intervention study to determine the minimum effective volume of a drug combination. The principle statistical method applied in this study is Staircase Up-down method as described by Dixon and Massey.([i]) Results: By using the log transformation of the data of required volume and outcome as successful or unsuccessful we have calculated EV 50 = 11ml and EV 90 = 14ml. Conclusion: Minimum Effective Volume in 90% individuals (MEV 90) for a combination of 0.25% bupivacaine and 1% lignocaine for ultrasound guided achial plexus block via supraclavicular approach is 14ml.