Phenic Nerve Injury During Anterior Scalenectomy, Can it Be Avoided with Minimal Bipolar Coagulation Use? A Prospective Single-Center Study.

Introduction: Phrenic nerve injury may be iatrogenic or traumatic in origin. Affected patients may develop dyspnea, atelectasis, and occasionally pneumonia. Transient nerve palsy has been reported in supraclavicular brachial plexus explorations, however, the incidence, etiology, and clinical implications are poorly understood. We hypothesize heat generated by the use of electrocautery during anterior scalenectomy may cause transient nerve dysfunction. Here we report a prospective series of patients who underwent anterior scalenectomy for thoracic outlet syndrome (TOS) using traditional and a modified electrocautery-sparing approach. Methods: Beginning in April 2018, all patients undergoing anterior scalenectomy for thoracic outlet decompression underwent routine post-operative chest radiographs. In the first period of the study, patients underwent decompression using a traditional surgical technique for muscle resection. In the second period of the study, a modified electrocautery-sparing approach was used. Detailed clinical, radiographic and surgical findings are presented. Results: Fifty anterior scalenectomies were performed, 7 using the traditional technique and 43 with the modified electrocautery-sparing technique. Six patients undergoing traditional muscle resection developed radiographic evidence of phrenic nerve palsy. No patients in the electrocautery-sparing cohort developed radiographic or clinical injuries, X2 (1, N = 50) = 35 (p <0.05). Diaphragm elevation improved and/or resolved in most patients. There were no complications associated with the modified technique, notably no symptomatic hemorrhage. Conclusion: Phrenic nerve injury is a known complication after thoracic outlet decompression, which can be evaluated with postoperative chest radiographs. A modified electrocautery-sparing approach during scalenectomy decreased the risk of phrenic nerve injury in this prospective study.