Case Report: Early diaphragmatic plication for combined phrenic and recurrent laryngeal nerve injury after VATS thymectomy.

Video-assisted thoracoscopic surgery (VATS) thymectomy may cause phrenic nerve injury (PNI) or recurrent laryngeal nerve (RLN) injury. Combined PNI and RLN injury is rare but can cause fatal respiratory failure. This study reported a case of VATS thymectomy in a 50-year-old man. The patient received a VATS thymectomy at an external hospital and presented to our hospital 10 days later with severe dyspnea and abdominal distention. Pre-surgery radiologic examination identified a 1.6-cm anterior mediastinal mass, and thymoma was considered. The pathology report confirmed benign reactive lymph node hyperplasia. The patient was hypoxemic with a PaO2 of 54 mmHg in room air. Pulmonary CT angiography ruled out pulmonary embolism. Laryngoscopy and fluoroscopic sniff test showed paradoxical left hemidiaphragm movement, leading to a diagnosis of left vocal cord paralysis. Chest CT revealed left lower lobe atelectasis with severe gastric distension that compressed the left hemithorax. Removal of the mucus plugs by bronchoscopy gave short-term relief. Bilevel positive airway pressure (BiPAP) caused a counterintuitive increase in gastric distension, which is expected after air enters an incompetent glottis. We proposed that combined PNI and RLN injury leads to ineffective cough, aerophagia, and a self-reinforcing pathophysiological cycle. Conservative treatment failed. Single-incision VATS left diaphragmatic plication was performed on hospital day 7 at our hospital. Oxygen saturation returned to normal, the lung re-expanded, and the abdominal girth reduced by 14 cm in less than 48 h. This report demonstrated the effect of combined PNI and RLN injury after VATS thymectomy and suggested early diaphragmatic plication as a potential therapeutic option in cases failing to respond to conservative treatment.