Persistent diaphragmatic paralysis associated with interscalene nerve block after total shoulder arthroplasty: a case report

摘要

Interscalene nerve blocks (ISBs) have become routine adjuncts toshoulder surgery because they have led to significant decreases inpostoperative pain, reduced requirements for opioid pain medication,earlier mobilization, quicker hospital discharge, decreased unplannedhospital readmission, and increased patient satisfaction.1,4,6,11Although ISBs are regularly performed, they are not without risk andcarry an overall complication rate between 2% and 4%.9Transient ipsilateral hemidiaphragmatic paralysis can be observedin association with ISB, and may transiently occur inup to 100% of patients because the phrenic nerve is close to thetarget brachial plexus nerve roots.1,6-8,13 However, persistenthemidiaphragmatic paralysis is exceedingly rare after ISB, with onlylimited case reports documenting longstanding decreases in respiratoryfunction and, in some instances, compromise in the patient’soverall functional capacity.5,7,8,13,14The etiology of persistent phrenic nerve dysfunction linked withISB remains unclear, and numerous mechanisms have beenproposed.5,7,8,13We offer an illustrative case report of a patient withpersistent ISB-associated diaphragmatic paralysis, while calling attentionto this condition and identifying risk factors to accelerateaccurate diagnosis and treatment with the goal of optimizing functionaloutcomes.