Hypoxic respiratory failure due to phrenic nerve palsy from an interscalene brachial plexus block and previously asymptomatic pulmonary embolism

Abstract

Interscalene brachial plexus block is a common regional anesthesia method for upper extremity surgery. A rare complication of this procedure is dyspnea secondary to phrenic nerve palsy and hemidiaphragm paralysis. In our case, this rare complication diagnosed using ultrasound led to the diagnosis of a previously asymptomatic pulmonary embolism. The use of ultrasonography was key in the diagnosis of the iatrogenic nerve palsy and was part of a multiple-modality diagnostic workup for her hypoxemia. © 2011 Springer-Verlag.