Brachial plexus block is a frequently used technique for upper extremity surgery. All present approaches and techniques have certain advantages and disadvantages. It's necessary to develop a new approach to brachial plexus block which 1) provides reliable anesthesia, 2) is easy to perform, 3) isn't restricted by posture, 4) provides extensive sensory distribution, 5) causes as few complications as possible, 6) easily place a secured catheter for post-operative analgesia. The investigators established the retrograde infraclavicular brachial plexus block approach. The investigators compared and verified the feasibility, efficacy and safety of this new approach with other classic approaches to brachial plexus block.

Traditional brachial plexus block approaches have certain limitations. This study evaluated the effectiveness, safety and feasibility of a new retrograde infraclavicular brachial plexus block as compared with interscalene and supraclavicular approaches. 90 patients scheduled for elective upper limb surgery were recruited and randomized into three groups, 30 for each group. Patients of Group A received retrograde infraclavicular block, interscalene (by Winnie) approach for Group B and supraclavicular (by Kulenkampff) approach for Group C. The retrograde infraclavicular block was performed with the insertion point medial to the coracoid process and the needle advanced to ipsilateral interscalene groove. Neurostimulation was used and 40ml of 0.5% ropivacaine were injected. Sensory block, adverse effects and complications were evaluated and recorded every 5 minutes until 30min after local anesthetic injection. The needle insertion depth, angles in coronary and sagittal planes of Group A were also recorded. Success rate of each nerve sensory block, sensory block result, complications, rate of satisfaction, rate of failure and incidence rate of adverse effects are all compared among groups.

Inclusion Criteria:

• ASA physical status Ⅰ~Ⅱ
• Scheduled for elective upper extremity surgery

Exclusion Criteria:

• Age <18 yr or >60 yr
• Body weight <50kg or >100kg
• Serious brain, heart, lung, liver, kidney diseases or diabetes mellitus
• Incapability or refusing to be enrolled
• Infection at the site of puncture, skin ulcer
• Coagulopathy
• Contralateral phrenic nerve paralysis, contralateral recurrent laryngeal nerve paralysis or pneumothorax