Surface stimulation to determine needle direction and angle when performing an infraclavicular brachial plexus block.

The infraclavicular approach to the brachial plexus is a safe and reliable technique for surgery of the upper extremity. When performing the block, the anesthesiologist must appreciate three variables: needle direction, needle angle to the chest wall, and needle depth. Surface stimulation is an easy technique that can reliably predict both needle direction and needle angle.