better techniques of airway anastomosis and routine use of corticosteroids peri-operatively, the incidence of bronchial anastomotic complications has been reduced drastically.45 When a bronchial anastomotic complication is suspected, the patient should have a chest x-ray, fiberoptic bronchoscopy, and a chest CT scan to document the presence of any mediastinal pathology such as collections of fluid or air.

Ischemia of the airway can be seen on bronchoscopy as patchy zones of necrosis of the donor airway mucosa. This is a common finding and if limited to the superficial layers, has no clinical significance and ultimately heals.15 However, is-chemic necrosis seen at the suture line is usually associated with some degree of dehiscence. Membranous wall defects generally heal without any airway compromise, whereas cartilaginous defects usually result in some degree of late stricture. Significant dehiscence involving greater than 50% of the circumference of the airway may result in compromise of the integrity of the airway. Early post-transplantation, this form may manifest with air leak or the features of sepsis due to mediastinal infection. This problem should be managed expectantly by gentle mechanical debridement to maintain a satisfactory airway patency.15 If extensive dehiscence occurs, a massive air leak may result, and rarely, fistulization can occur between the pulmonary artery and bronchial anastomosis. Massive dehiscence with an uncontrolled leak or medi-astinal contamination has been treated with successful retransplantation in a small number of cases. The first priority of treatment during the acute phase of an anas-tomotic dehiscence is to provide adequate drainage, either by chest tube, percutaneous drainage under CT guidance, or even mediastinoscopy with transcervical drainage. In the intermediate phase, periodic rigid brochoscopy and dilatation of the airway may be necessary.

Late sequelae involve the development of stricture or the development of a malacic segment of bronchus in which symptoms may include dyspnea, stridor or wheezing. Chronic airway stenoses can present significant management prob-lems.15,30 A right main bronchial anastomosis is usually easily managed by repeated dilatation and ultimate placement of an endobronchial stent to maintain pa-tency.15,45 On the left side, strictures are somewhat more difficult to manage. Dilatation is technically more difficult to accomplish because of its angulation. Furthermore, the lobar bifurcation just distal to the stricture site does not provide an adequate length of bronchus for the placement of large-caliber dilating bronchoscopes. A stent across a stricture in this location may result in occlusion of one of the lobar orifices.

Silastic endobronchial stents are preferred over other types. These stents can be inserted easily over a rigid bronchoscope and are tolerated exceptionally well. However, patients require daily inhalation of N-acetylcystine to keep the stents patent. Stents have resulted in dramatic improvement in pulmonary function.46 Fortunately, most of these stents have been required only temporarily. After several months, most patients are able to maintain satisfactory airway patency without the stent.

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