Safety and efficacy of the infraclavicular nerve block performed at low current.

It has recently been suggested that peripheral nerve or plexus blocks performed with the use of a nerve stimulator at low currents (<0.5 mA) may result in neurologic damage. We studied the infraclavicular nerve block, performed with the use of a nerve stimulator and an insulated needle, in a prospective evaluation of efficacy and safety. During a one-year period, 248 patients undergoing infraclavicular nerve block were evaluated for block success rate and incidence of neurologic complication. All blocks were performed with the use of a nerve stimulator and an insulated needle at < or =0.3 mA. Success rate was 94%, which increased to 96% with surgical infiltration of local anesthetic. There were no intraoperative or immediate postoperative complications noted. After one week, only one patient had a neurologic complaint, and this was surgically related, referable to surgery performed on the radial nerve. We conclude that infraclavicular nerve blocks performed at low currents (< or =0.3 mA) are safe and effective.