[Tracheobronchial stents for management of airway stenosis]

Airway prostheses provide an excellent method for providing relief for patients with malignant or benign stenoses. Two types of prostheses are currently available: rigid silicone stents and metallic expandable stents. Silicone stents have been proven to be well tolerated, nonreactive, and easily removable during several decades of clinical application. However, they impair the drainage of sputum because of interrupted ciliary movement. Subsequently, retained secretions within the stent lumen can be obstructive. In addition, dislodgment frequently occurs because of their rigidity. The advantages of metallic expandable stents are as follows: 1) they can be inserted under local anesthesia with relative simplicity: 2) they do not impair the drainage of sputum: 3) ventilation is usually possible even if the metallic mesh stent covers another bronchus: and 4) their flexibility allows them to bend and conform better than rigid stents to tortuous airway stenoses. The disadvantages of metallic stents are: 1) tumor or granulation ingrowth can occur because of their porosity: 2) removal is difficult: and 3) there is limited experience with their use because they have only recently been employed for airway stenoses.