Tracheal elastic recoil-induced carinal shift causing intraoperative hypoxemia after resection of massive substernal goiter: A case report

A large substernal goiter can severely compress and displace the trachea, complicating airway and anesthetic management. We report a 61-year-old deaf-mute man with a giant substernal goiter causing critical tracheal stenosis (6 mm diameter, 2.7 cm length). Awake intubation was successfully achieved using a combined videolaryngoscope-fiberoptic bronchoscope technique. Following resection of the left thyroid lobe, the patient developed refractory hypoxemia (SpO₂ 85%) unresponsive to standard interventions. Stepwise withdrawal of the endotracheal tube by 1 cm improved oxygenation from 90% to 97%. This finding suggests a novel mechanism of ventilation-perfusion mismatch: Post-resection tracheal elastic recoil and shortening led to cephalad carinal shift relative to the fixed tube, resulting in functional malposition and unilateral ventilation. This case highlights the importance of dynamic monitoring and timely adjustment of endotracheal tube position during procedures that alter airway anatomy.