History
Infants present after a few weeks of life with expiratory stridor (also called laryngeal crow). Expiratory stridor may worsen with supine positioning, crying, and respiratory infections. Hoarseness, aphonia, breathing problems, and feeding difficulties have been described.
Obtain a history of an acquired etiology, such as prolonged intubation, tracheostomy, chest trauma, recurrent tracheobronchitis, cartilage disorder (relapsing polychondritis), or lung resection.
Physical Examination
Inspiratory retractions of supraclavicular and intercostal spaces may occur. Thoracic deformity may be present in cases of chronic tracheomalacia, especially in younger patients. Auscultation reveals normal inspiration but abnormal expiratory noises. Not uncommonly, infants may demonstrate signs of growth failure.
-
Lateral chest radiograph shows excessive tracheal narrowing.
-
This shows the trachea during inspiration and expiration. Tracheal collapse of more than 50% during expiration is diagnostic of tracheomalacia.
-
The mechanism of tracheal narrowing is shown here in healthy cases and in cases of tracheomalacia. Adapted from Feist JH, et al. Chest 68:3, Sept, 1975.
-
Healthy trachea is visualized endoscopically.
-
A 58-year-old woman with a history of polychondritis presented with inspiratory stridor and respiratory difficulties. The chest radiograph shows narrowing of the distal trachea on bronchoscopy. More than a 50% decrease in tracheal lumen occurred during expiration (see CT images).
-
The CT scan of a 58-year-old woman with a history of polychondritis who presented with inspiratory stridor and respiratory difficulties shows tracheal narrowing of the distal trachea.
-
CT image showing tracheal narrowing in a 58-year-old woman with a history of polychondritis who presented with inspiratory stridor and respiratory difficulties.
-
A 3-dimensional reconstruction of CT scan images confirms the presence of tracheomalacia in a 58-year-old woman with a history of polychondritis who presented with inspiratory stridor and respiratory difficulties.
-
Patterns of upper airway obstruction are presented here. Patient A has fixed upper airway obstruction. Patient B has variable extrathoracic obstruction, eg, vocal cord dysfunction. Patient C has variable intrathoracic obstruction, eg tracheomalacia.
-
A flow volume loop shows a pattern of variable extrathoracic obstruction. Truncation of the expiratory limb is present. As the pleural pressure exceeds the airway pressure, airway collapse occurs due to flow limitation during expiration and not during inspiration.
-
A flow volume loop shows the classic pattern of fixed upper airway obstruction. Truncation of both inspiratory and expiratory limbs is present.
