Infraclavicular brachial plexus block: variation in approach and results in 360 cases.

BACKGROUND AND OBJECTIVES: Brachial plexus block is clinically useful. Although the infraclavicular approach to brachial block is the less commonly used form it may offer advantages. We describe the results with three local anesthetic mixtures used during this observational study.

METHODS: Three hundred and sixty patients, ASA physical status I and II, scheduled for upper extremity orthopedic surgery, were anesthetized with an infraclavicular brachial plexus block. They were divided into three groups (120 patients each) by type of 40-mL anesthetic mixture: group I had even parts of 2% plain lidocaine and 0.5% bupivacaine with epinephrine 1:200,000; group II had even parts of 1% plain lidocaine and 0.25% bupivacaine with epinephrine 1:200,000; and group III had even parts of 1.5% plain lidocaine and 0.37% bupivacaine with epinephrine 1:200,000. Plexus identification was made by nerve stimulator. The observational assessments were: adequacy and latency time of the block, tourniquet tolerance, postoperative analgesia, local anesthetics doses, sedative doses, complications, and side effects.

RESULTS: In groups I, II, and III, adequacy of the block was 95, 75, and 96%, latency time was 10.4, 12.9, and 10.9 minutes, tourniquet tolerance was 99, 84, and 98%, postoperative analgesia time was 663, 331, and 502 minutes, anesthetic doses of lidocaine/bupivacaine were 5.2/1.3, 2.9/0.7 and 4.1/1.1 mg/kg, respectively. Differences were noted between group II and groups I and III (P range: .01-.0001). Sedatives in adequate blocks were midazolam with/without fentanyl (2-3 mg/50-100 microg) in all groups. There were two complication cases with no consequences: two vascular punctures that did not hold up or delay the anesthetic or surgical procedure. There were no clinical manifestations or side effects.

CONCLUSIONS: The infraclavicular approach described is effective. It produced reliable anesthesia and is associated with minimal complications and side effects. The mixture of local anesthetics used in group II is not adequate for producing reliable anesthesia.