Overview
Definition:
Tracheomalacia is a condition characterized by weakness of the tracheal cartilage and walls, leading to dynamic airway collapse during increased airflow demands, such as crying, feeding, or coughing
This malacia can affect the entire trachea or specific segments, often exacerbated by extrinsic compression.
Epidemiology:
Congenital tracheomalacia is the most common form in infants, occurring in approximately 1 in 2,000 live births
It is often associated with other congenital anomalies, including cardiac defects, esophageal atresia, and Down syndrome
Acquired tracheomalacia can occur at any age due to prolonged intubation, tracheostomy, or external compression.
Clinical Significance:
Tracheomalacia is a crucial differential diagnosis in infants presenting with stridor, recurrent respiratory infections, and feeding difficulties
Early recognition and appropriate management are vital to prevent chronic lung disease, failure to thrive, and potentially life-threatening respiratory distress, making it a high-yield topic for DNB and NEET SS aspirants.
Clinical Presentation
Symptoms:
Stridor, predominantly expiratory or biphasic
Barking cough, often described as seal-like
Recurrent or persistent pneumonia
Cyanotic episodes
Tachypnea and retractions
Difficulty feeding, leading to aspiration and poor weight gain
Symptoms worsen with exertion, crying, or supine positioning.
Signs:
Audible stridor on auscultation, may be exacerbated by feeding or crying
Wheezing that does not improve with bronchodilators
Paradoxical chest wall motion during respiration
Retractions of intercostal and suprasternal spaces
Poor feeding tolerance
May have signs of associated congenital anomalies.
Diagnostic Criteria:
There are no universally established diagnostic criteria for tracheomalacia
Diagnosis is primarily based on clinical suspicion, supported by characteristic findings on dynamic airway imaging
Severity is often graded based on the degree of airway collapse observed during these evaluations.
Diagnostic Approach
History Taking:
Detailed birth history (e.g., prematurity, prolonged ventilation)
History of choking or gagging during feeds
Recurrence of cough and wheeze
Associated symptoms of gastroesophageal reflux (GER) or cardiac anomalies
Family history of airway disorders.
Physical Examination:
Auscultation for stridor, wheezing, and cough characteristics
Assess for retractions and paradoxical breathing
Observe feeding mechanics and any signs of aspiration
Palpate for external masses or lymphadenopathy
Assess for signs of associated syndromes or cardiac defects.
Investigations:
Flexible bronchoscopy is the gold standard for direct visualization of dynamic airway collapse and assessment of severity
Fluoroscopy, particularly dynamic cinefluoroscopy of the airway during respiration and crying, can be useful
Chest X-ray is often normal but can reveal signs of secondary complications like pneumonia or atelectasis
Esophageal pH monitoring or barium swallow may be indicated if GER or aspiration is suspected.
Differential Diagnosis:
Laryngomalacia, subglottic stenosis, vocal cord paralysis, vascular rings, mediastinal masses, foreign body aspiration, pneumonia, bronchiolitis, asthma, gastroesophageal reflux disease.
Management
Initial Management:
Supportive care focused on optimizing oxygenation and ventilation
Management of associated conditions like GER and cardiac defects
Referral to a pediatric pulmonologist or otolaryngologist for definitive evaluation.
Medical Management:
Management of GER with antacids, H2 blockers, or proton pump inhibitors
Use of humidified air
Suctioning of secretions as needed
Careful management of respiratory infections
Avoidance of triggers that worsen airway collapse.
Surgical Management:
Surgical intervention is considered for severe symptomatic tracheomalacia unresponsive to conservative management
Options include tracheostomy (temporary or permanent), aortopexy, or in select cases, tracheoplasty (e.g., slide tracheoplasty or costal cartilage graft reconstruction).
Supportive Care:
Nutritional support to ensure adequate weight gain
Respiratory physiotherapy to aid secretion clearance
Close monitoring for respiratory distress and aspiration events
Parental education on feeding techniques and recognition of warning signs.
Dynamic Airway Evaluation Specifics
Bronchoscopy:
Performed under sedation, observing the trachea during spontaneous breathing, crying, and Valsalva maneuver
Document the degree of collapse at different tracheal levels and identify any intrinsic or extrinsic airway narrowing
A collapse of >50% is generally considered significant.
Fluoroscopy:
Dynamic imaging, often with contrast, to visualize airway caliber changes during the respiratory cycle and with maneuvers like crying or coughing
Can be performed in multiple projections
Useful for identifying dynamic collapse that may not be obvious on static imaging.
Other Imaging:
CT angiography may be used to evaluate for vascular rings or slings that can cause extrinsic compression
MRI can also provide detailed anatomical information but is less effective for dynamic assessment.
Interpretation Challenges:
Differentiating intrinsic malacia from dynamic collapse due to extrinsic compression
Assessing the functional impact of observed collapse on gas exchange
Identifying the severity and pattern of collapse (e.g., anterior vs
posterior wall, focal vs
diffuse).
Complications
Early Complications:
Severe respiratory distress and failure
Aspiration pneumonia
Persistent atelectasis
Hypoxemia.
Late Complications:
Chronic lung disease
Failure to thrive
Recurrent otitis media
Tracheal damage from prolonged intubation or tracheostomy
Developmental delay due to chronic hypoxia.
Prevention Strategies:
Early diagnosis and prompt management
Aggressive treatment of GER
Judicious use of endotracheal tubes with appropriate sizing and cuff pressure management
Early surgical intervention for severe cases when indicated.
Prognosis
Factors Affecting Prognosis:
Severity of tracheomalacia
Presence of associated congenital anomalies
Promptness of diagnosis and treatment
Response to conservative and surgical management
Degree of airway compromise and associated pulmonary issues.
Outcomes:
Mild cases may resolve spontaneously with growth and maturation of the airway
Severe cases, especially those with associated anomalies, may require prolonged medical or surgical management and can have a less favorable outcome
Long-term follow-up is often necessary.
Follow Up:
Regular clinical assessments, especially if symptoms persist or recur
Pulmonary function tests may be considered in older children
Ongoing monitoring for respiratory infections and feeding difficulties
Re-evaluation with dynamic airway imaging if symptoms worsen or change.
Key Points
Exam Focus:
Tracheomalacia is a dynamic airway collapse due to cartilage weakness
Bronchoscopy is the gold standard for diagnosis and severity assessment
Symptoms are often exacerbated by increased airflow demands
Associated conditions like GER and cardiac defects are common.
Clinical Pearls:
Always consider tracheomalacia in infants with persistent stridor and recurrent pneumonias
Differentiate from laryngomalacia by the typical location and timing of the collapse (expiratory)
Dynamic imaging is crucial
static X-rays are often unrevealing for the malacia itself
Tracheostomy offers a proximal airway, bypassing the collapsible segment.
Common Mistakes:
Attributing all noisy breathing to laryngomalacia without considering subglottic or tracheal pathology
Relying solely on static imaging for diagnosis
Delaying bronchoscopy in cases of persistent or worsening symptoms
Underestimating the impact of GER on airway symptoms.