Physiologic studies of tracheobronchial stents in airway obstruction

When airway obstruction is due to extraluminal compression and/or dynamic collapse, metal and silicone rubber prosthetic stents may stabilize the affected airway. Through a rigid bronchoscope, we inserted three metal stents in two patients and 18 silicone stents in 15 adult patients with symptomatic tracheobronchial compression and dynamic airway collapse. The underlying cause was malignancy in three patients; benign tracheobronchial malacia in three patients, two of whom refused surgical resection; and tracheobronchial stenosis that developed at the anastomotic site following lung transplantation in 11 patients. Clinical status and lung function studies were analyzed before and after stent insertion. Following stent insertion, airway diameter at least doubled and near normal patency of the affected tracheobronchial tree was achieved in every patient using stents of axial length 4 to 5 cm. The stents were well tolerated clinically, and all patients noted immediate relief of dyspnea. Following stent insertion, the forced vital capacity (FVC) increased from 64 ± 21% predicted (mean ± 1 SD) to 73 ± 19% predicted, p < 0.1; the forced expiratory volume in 1 s (FEV₁) from 49 ± 25% predicted to 72 ± 26% predicted, p < 0.02 the ratio of the FEV₁/FVC from 59 ± 16% to 78 ± 15%, p < 0.01; and the maximum flow at 50% expired FVC from 38 ± 26% predicted to 72 ± 31% predicted, p < 0.01.