The patient was a 45-year-old male with right-side tongue cancer (T4aN2b) ; general anesthesia had been planned for a tracheostomy, bilateral radical neck dissection and reconstruction with a rectus abdominis muscle flap. Three days before the scheduled operation, the tumor started bleeding and a tracheotomy was performed under intravenous sedation to prevent airway obstruction resulting from blood clotting. The day before the scheduled surgery, extensive pneumomediastinum and subcutaneous emphysema were identified on a chest computed tomography (CT) image, and the planned operations were deferred. One week later, the size of the pneumomediastinum had clearly decreased, and the operations were performed as previously planned. During the operations, the internal airway pressure was kept lower to prevent tension pneumomediastinum, and after the operations, the patient was sedated with the continuous injection of dexmedetomidine. The operations were performed without any further events, and the postoperative course was also uneventful. In this case, one of the causes of the pneumomediastinum and subcutaneous emphysema was considered to be air leakage or air aspiration into the soft tissues of the neck and the mediastinal space through the tracheostomy wound as a result of events related to a higher airway pressure, such as cuffing. The frequency of pneumomediastinum and subcutaneous emphysema after tracheostomy is relatively rare. However, these complications after a tracheostomy require careful attention.
