A case of thoracic pneumatosis due to severe coughs and tracheal tube displacement induced by tracheal tube size mismatch

BACKGROUND: Thoracic pneumatosis during mechanical ventilation may be life-threatening. We encountered a patient with thoracic pneumatosis after frequent displacement of the tracheal tube with an overinflated cuff. CASE PRESENTATION: We admitted a 62-year-old man to the intensive care unit (ICU) due to respiratory failure. We secured his airway using a cuffed 8.5-mm tracheal tube. However, air leakage did not stop with the regular intracuff pressure (25 cm H(2)O) because the diameter of his trachea was too large for the tracheal tube inserted. In addition, a chest X-ray examination revealed rostral tube displacement. Therefore, we applied a higher intracuff pressure (35 cm H(2)O) to prevent air leakage and tracheal tube movement. However, severe coughing episodes developed, and 3 days after ICU admission, a chest X-ray and CT scan revealed pneumomediastinum and pneumothorax. We did not have larger tracheal tubes in stock. We decided to use a tracheostomy tube instead, which we expected to be placed securely and to prevent tube displacement. After tracheostomy, the severe coughing episodes became infrequent. Finally, we weaned the patient from mechanical ventilation 12 days after ICU admission. CONCLUSIONS: The clinical signs and symptoms in our patient point to tracheal tube size mismatch as the cause of pneumothorax.