Prolonged hemidiaphragmatic paralysis following interscalene brachial plexus block

We present a case of persistent phrenic nerve paralysis after a successful interscalene brachial plexus block. In addition, there was no observed diaphragmatic stimulation, and the patient underwent an uneventful early postoperative period. Warning signs of a complication were either missed or absent until several days after discharge from the ambulatory surgical unit.