Tracheal Surgery: Posterior Splinting Tracheoplasty for Tracheomalacia

Tracheomalacia (or more commonly tracheobronchomalacia) in adults is uncommon and is often an incidental finding on a chest computed tomographic (CT) done for another reason with mild to moderate airway collapse seen on an expiratory study. These patients just need reassurance. Severe airway collapse is rare and usually associated with symptoms such as dyspnea, incessant coughing, inability (or difficulty) raising secretions, and repeated chest infections. These patients are often miserable, and it often takes them a long time to be diagnosed and referred, as many clinicians are not familiar with this uncommon disease. If patients are smokers and have associated chronic obstructive pulmonary disease, it can be very troublesome and difficult to sort out which disease is most important and whether to offer an operation. I tend to shy away from those with significant chronic obstructive pulmonary disease unless I am quite convinced that the tracheomalacia is very dominant. The evaluation process starts with a high-quality dynamic chest CT with inspiratory and expiratory views to determine the degree of tracheomalacia and whether it extends to the major bronchi (Figure 1, Figure 2). If severe malacia is found, then an awake functional bronchoscopy is done to verify this and further assess the airway. All airways collapse with a strong cough, and that finding is not diagnostic of tracheomalacia. If the airway collapses during quiet breathing with exhalation, then more severe malacia is confirmed (Figure 3, Figure 4). Sometimes coughing is incited by the opposition of the anterior and posterior walls of the airway. There are 2 anatomical forms of tracheomalacia, the classic soft or weak anterior tracheal cartilages (cartilaginous malacia) with a redundant posterior membranous wall (Fig. 1) (often with tracheobronchomegaly or Mounier-Kuhn syndrome) and excessive forward displacement of the membranous wall (membranous malacia) (Fig. 2). Pulmonary function tests are performed to document any other lung pathology and help assess the risk for thoracotomy. There is no specific finding on pulmonary function studies that is diagnostic of tracheomalacia. Some have advocated a trial of a silicone Y stent in an attempt to document whether symptoms and quality of life are improved with airway stenting as a diagnostic strategy to decide if tracheoplasty would be beneficial. I have not found this particularly helpful, as several patients have not been able to tolerate a stent even for 1 day because of coughing and airway irritation. In general, I recommend an operation if severe symptoms match the imaging and bronchoscopic findings of severe expiratory collapse of the airway (Figure 5, Figure 6, Figure 7, Figure 8, Figure 9, Figure 10).

Patients who are properly selected and have a good anatomical result often mention early in the postoperative period that they feel they are better despite the presence of a painful thoracotomy incision. The morbidity is usually pulmonary in nature and runs the gamut of atelectasis, sputum retention, pneumonia, and respiratory failure. Mortality is quite rare. Quality-of-life measures are improved in most patients, and functional testing with the 6-minute walk test also demonstrates improvement in most patients. Pulmonary function tests usually do not measurably improve. Certainly one of the problems in evaluating these patients (either preoperatively or postoperatively) is the subjective nature of their symptoms and how they perceive their respiratory health. In the end, the goal is a satisfied patient despite the lack of a quantifiable metric. Indeed, postoperative surveys of patients have reported that most patients are improved and satisfied with the results of a tracheoplasty.^,