What are the guidelines for managing subglottic stenosis?

Management of Subglottic Stenosis

For patients with subglottic stenosis, treatment should be tailored to the etiology, with immunosuppressive therapy recommended as first-line treatment for inflammatory stenoses and surgical approaches reserved for fibrotic or non-responsive cases. 1

Diagnostic Evaluation

• Comprehensive airway assessment:

  • Contrast-enhanced CT scan and/or MRI to assess extent of stenosis and cartilage involvement
  • Endoscopy (microlaryngoscopy and bronchoscopy) to determine location, severity, and nature of stenosis
  • Evaluation of etiology (post-intubation, autoimmune, idiopathic, congenital)

• Risk factors for acquired subglottic stenosis:

  • Intubation for ≥7 days
  • Three or more intubations 2
  • Inappropriately large endotracheal tubes (tube size-to-gestational age ratio >0.1) 2
  • Concomitant infection with mucosal injury 2

Treatment Algorithm Based on Etiology

1. Inflammatory/Autoimmune Stenosis (e.g., GPA/Vasculitis)

• First-line treatment: Immunosuppressive therapy over surgical dilation with intralesional glucocorticoid injection alone 2

  • Requires management by otolaryngologist or pulmonologist with expertise in these lesions
  • Immunosuppressive regimens typically include systemic glucocorticoids plus steroid-sparing agents

• For refractory cases: Consider adding IV immunoglobulin (IVIG) to current therapy as adjunctive treatment for short-term control 2

2. Post-intubation or Fibrotic Stenosis

• Endoscopic management options:

  • Balloon dilation
  • Radial incisions with carbon dioxide laser or cold knife
  • Combination techniques
  • Adjunctive measures: mitomycin application and/or glucocorticoid injection 3

• For severe or recurrent stenosis:

  • Laryngotracheal resection and reconstruction for definitive treatment
  • Success rates of 98.7% reported with surgical resection 4

3. Critical Airway Narrowing

• Emergency management:
  • Surgical dilation with intralesional glucocorticoid injection concurrent with immunosuppressive therapy 1
  • Tracheostomy for airway bypass when necessary (avoid when possible due to impact on speech and quality of life) 1

Factors Affecting Treatment Success

• Mitomycin application has been associated with extended time intervals between endoscopic treatments (157 days longer on average) 3

• Predictors of poor outcomes:

  • Stenosis length >4.5 cm 4
  • Involvement of vocal cords or proximity to glottis (within 1.5 cm) 4
  • Prior failed interventions (multiple dilations, laser treatments)

Special Considerations

• Congenital stenosis often requires surgical correction with potential need for tracheostomy 1

• Acute exacerbations with respiratory infections may be managed with:

  • β-adrenergic agents (racemic epinephrine) for temporary relief
  • Systemic corticosteroids to reduce edema 1

• Post-COVID-19 considerations:

  • Heightened vigilance for laryngotracheal injury including subglottic stenosis 2
  • Multidisciplinary approach involving otolaryngologists, pulmonologists, and critical care specialists

Follow-up and Monitoring

• Regular endoscopic evaluation to assess treatment response and detect early recurrence
• For patients with autoimmune causes, treatment decisions should be based on clinical symptoms rather than ANCA titer results alone 2
• Long-term follow-up is essential as recurrence is common, particularly with endoscopic management