Abstract: ［Abstract］〓Objective〖HTSS〗〓To observe the effect of dualinjection on coracoid approach brachial plexus block guided by nerve stimulator for upper extremity surgery.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓Eighty patients ASA classⅠ-Ⅱscheduled for surgery in elbow,forearm,wrist or hand were randomly divided into two group: dualinjection group(group D) and singleinjection group(group S), 40 patients in each group. All cases were received coracoid approach brachial plexus block guided by nerve stimulator. 40 mL 0.375% ropivacaine was injected after evoking one target muscle movement in group S. While two different muscle movements need to be evoke in group D. Sensory block and motor block was evaluated every 5 minutes after injection of the local anesthetic. The time required to complete the block, success rate and complications were also tanked notes.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The sensory block and motor block onset time in group D was significantly shorter than that in group S(P＜005) . The sensory block onset time for ulnar nerve and radial nerve in group D was significantly shorter than that in group S(P＜005). The motor block onset time for radial nerve in group D were significantly shorter than that in group S(P＜005). The success rate in group D was significantly higher than that in group S(P＜005) . The time required to complete the block in group D was longer than that in group S(P＜005). No significant complications occurred in the two groups.
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓Dualinjection technique can shorten sensory block and motor block onset time and increase block effect without increasing the complications for coracoid approach brachial plexus block. But it requires longer time to complete the block.

Key words: nerve block；brachial plexus； coracoid, dualinjection