This document discusses the costoclavicular block (CC-BPB) technique for shoulder surgery anesthesia. It notes that a 25 ml dose of 0.5% ropivacaine provided faster onset of sensory blockade and earlier readiness for surgery compared to 20 ml. Piercing the septum between compartments during the block can evoke motor responses from the medial or posterior cords. A 19-ml dose of 0.5% ropivacaine is likely to provide effective surgical anesthesia for 95% of patients, with a MEV90 of 20.92 ml. The CC-BPB has continuity with the supraclavicular space and is suitable for shoulder surgeries.