Stenting of critical tracheal stenosis with adjuvant cardio-pulmonary bypass.

Severe and critical central airway obstruction causing impaired ventilation and/or oxygenation can impose tremendous challenges on the interventional pulmonologist. Near total airway obstruction can rapidly evolve into potentially fatal complete airway occlusion during bronchoscopic airway manipulation under moderate sedation; as well as during the induction of the general anesthesia. Although there are currently interventional pulmonary procedures available to tackle the critical airway obstruction in extreme situations, cardio-pulmonary bypass should be considered prior to the intervention to maintain the adequate gas exchange during the procedure. Orotracheal intubation with mechanical ventilation in this situation can be fatal itself if the obstructing airway lesion functions as a "one way valve" allowing air to follow distally during inspiration but impeding expiratory flow leading to gas trapping, high intrathoracic pressure, tension pneumothorax, and ultimately a cardiac arrest.