Variable tracheal stenosis related to body position.

We demonstrated a variable extrathoracic tracheal stenosis which developed after technically adequate tracheostomy and was worsened by changes in body position. When the patient's arms were above his head, minimal airway diameter was reduced 31 percent, and maximal inspiratory flow rate 37 percent below values measured with arms down, but expiratory flow rates were preserved. Tracheostomy may disrupt the integrity of tracheal support and allow airway collapse under circumstances of increased extratracheal or decreased intratracheal pressure.