Congenital Airway Anomalies

Laryngomalacia - Floppy Larynx Fun

• Most common congenital laryngeal anomaly & cause of stridor.
• Pathophysiology: Immature, "floppy" supraglottic structures (arytenoids, epiglottis) collapse inward during inspiration.
• Features:
  • Inspiratory stridor, onset by 4-6 weeks.
  • Worse: Supine, crying, feeding. Better: Prone.
  • Normal cry.
  • Severe cases: FTT, GERD, apnea.
• Diagnosis: Flexible laryngoscopy (awake) shows dynamic collapse; classic "omega-shaped" epiglottis.
• Management:
  • Most resolve spontaneously by 18-24 months (conservative).
  • Severe: Supraglottoplasty.

⭐ Laryngomalacia is the most common cause of congenital stridor, typically presenting with inspiratory stridor that worsens in the supine position or during agitation.

Tracheo/Bronchomalacia - Weak Windpipe Woes

⭐ Tracheomalacia often presents with a characteristic expiratory barking cough and can be associated with tracheo-esophageal fistula.

• Pathophysiology: Excessive compliance & dynamic collapse of tracheal/bronchial walls during expiration.
• Etiology:
  • Primary (Intrinsic): Congenital cartilage weakness.
  • Secondary (Extrinsic): Compression (e.g., vascular ring), post-intubation, inflammation.
• Clinical Features:
  • Expiratory stridor/wheeze, characteristic barking cough (worsens with crying, feeding, supine position).
  • Recurrent respiratory infections; severe cases: cyanotic spells (“dying spells”).
  • Symptoms may improve in prone position.
• Diagnosis:
  • Gold Standard: Flexible bronchoscopy (shows >50% luminal collapse during expiration).
  • Fluoroscopy, CT/MRI (to identify extrinsic compression).
• Management:
  • Conservative: Most resolve spontaneously by 1-2 years. Humidification, chest physiotherapy, GERD management.
  • CPAP/BiPAP for moderate symptoms.
  • Surgical (severe/refractory): Aortopexy, tracheopexy, tracheostomy.

Subglottic Stenosis & Webs - Narrow Escape Routes

Subglottic Stenosis (SGS): Airway narrowing below vocal cords.

• Types:
  • Congenital: Developmental (cricoid anomaly).
  • Acquired: Post-intubation (commonest), trauma, GERD.
• Symptoms: Biphasic stridor, barking cough, recurrent croup, dyspnea; worsens with URI.
• Diagnosis: Endoscopy (flex/rigid). X-ray (steeple sign, non-specific).

⭐ Congenital subglottic stenosis is often defined as a subglottic diameter <4mm in a full-term infant; Cotton-Myer grading is used for severity.

• Cotton-Myer Grading (% obstruction):
  • Grade I: 0-50%
  • Grade II: 51-70%
  • Grade III: 71-99%
  • Grade IV: No lumen

Subglottic Webs: Thin membrane in subglottis; rare.

• Symptoms: Symptoms like SGS; severity varies.
• Diagnosis: Endoscopy.

Management Approach:

• SGS Treatment: Observation, dilation, laser, cricoid split, LTR, CTR. Tracheostomy if severe.
• Web Treatment: Endoscopic division (cold knife/laser).

Vascular Rings & Slings - Artery Squeeze Play

• Anomalous vessels compress trachea/esophagus.
• Types & Features:
  • Double Aortic Arch: Complete ring; tracheal & esophageal squeeze.

    ⭐ A double aortic arch is the most common symptomatic vascular ring, causing both tracheal and esophageal compression.

  • Right Aortic Arch with Aberrant Left Subclavian Artery: Lig. arteriosum completes ring. Dysphagia lusoria.
  • Pulmonary Artery Sling: L. PA from R. PA, between trachea & esophagus. Posterior tracheal squeeze. Assoc. tracheal stenosis (ring-sling complex).
  • Innominate Artery Compression: Anterior tracheal squeeze by innominate artery.
• Symptoms:
  • Respiratory: Stridor (biphasic, expiratory ↑), wheeze, cough, apnea.
  • Esophageal: Dysphagia, feeding issues.
  • Symptoms worsen with feeding, crying, neck flexion.
• Diagnosis:
  • CXR, Barium swallow (indentations).
  • CT Angiography / MRI: Gold standard.
  • Bronchoscopy: Pulsatile compression, assess tracheomalacia.
• Management: Surgical division of ring/vessel reimplantation (PA sling).

High‑Yield Points - ⚡ Biggest Takeaways

• Laryngomalacia: Most common cause of stridor in infants; inspiratory stridor, often self-resolving.
• Subglottic Stenosis: Biphasic stridor; most common anomaly needing tracheostomy in young children.
• Vocal Cord Paralysis: Unilateral (weak cry, aspiration); Bilateral (severe stridor, airway compromise).
• Choanal Atresia: Bilateral is a neonatal emergency (cyanosis with feeding); CHARGE syndrome association.
• Tracheomalacia: Expiratory stridor/barking cough; dynamic collapse; associated with TEF.
• Laryngeal Webs: Stridor, weak cry/aphonia; incomplete recanalization; glottic most common.