Subglottic Stenosis: Symptoms and Treatment
Clinical Presentation
Subglottic stenosis presents with dyspnea, hoarseness, and inspiratory stridor, with fixed lesions producing biphasic stridor while dynamic lesions cause only inspiratory stridor. 1
Key Symptoms
- Respiratory symptoms: Dyspnea on exertion, restriction during physical activity, and inspiratory stridor are the hallmark presentations 1, 2
- Voice changes: Hoarseness is common, particularly in post-intubation cases 1
- Postextubation manifestations: Stridor, apnea and bradycardia, failure to tolerate extubation, and cyanosis or pallor in neonates 1
- Preterm infant presentation: Apnea may replace stridor due to easy fatigability and paradoxical response to hypoxemia 1
- Associated symptoms: Nasal congestion sensation may occur with progressive stenosis 2
Important Diagnostic Considerations
- Postextubation stridor is a significant marker for moderate to severe subglottic stenosis and warrants immediate evaluation 1, 3
- Fixed vs. dynamic lesions: Biphasic stridor indicates fixed glottic/subglottic lesions, while inspiratory stridor alone suggests dynamic lesions 1
- Differential diagnosis: Similar presentations can result from vocal cord injuries, glottic/subglottic webs or cysts, laryngomalacia, or extrathoracic tracheomalacia 1
Treatment Approach
For Vasculitis-Associated Stenosis (GPA/Autoimmune)
Immunosuppressive therapy with glucocorticoids combined with rituximab or cyclophosphamide is first-line treatment for active inflammation with stenosis in GPA patients, with surgical dilation reserved only for longstanding, fibrotic, or unresponsive stenoses. 3
- Medical management priority: Immunosuppression over surgical dilation alone for actively inflamed stenosis 3
- Surgical dilation with intralesional glucocorticoids: Reserved for longstanding, fibrotic stenoses unresponsive to immunosuppression 3
- Concurrent surgical intervention: Only when immediate intervention required (critical airway narrowing) 3
- Mandatory prophylaxis: Pneumocystis jirovecii prophylaxis for patients receiving rituximab (≥6 months after last dose) or cyclophosphamide 3
- Treatment outcomes: GPA and relapsing polychondritis patients show 75% improvement rates with corticosteroid injection plus dilation 4
For Idiopathic and Post-Traumatic Stenosis
Airway dilation, either alone or combined with other therapeutic modalities, is recommended for nonmalignant central airway obstruction with stenosis, with a multimodality approach utilizing dilation, ablative resection, and medical treatment achieving optimal outcomes. 2
- Serial intralesional steroid injection (SILSI): Increases inter-operative intervals and improves dyspnea and voice outcomes, with 65% of patients (37/57) not requiring further operative intervention 5
- Endoscopic balloon dilation: Effective under direct visualization or fluoroscopic guidance for distal tracheal and bronchial stenoses 3
- Electroresection: Alternative for fixed airway obstruction 3
- Limited endoscopic role: Restricted to short, recent, grade I or II mucosal stenosis cases; provides only temporary benefit due to frequent recurrences 6, 7
Surgical Management Algorithm
Anterior cricoid split is the preferred initial surgical approach for severe subglottic stenosis, allowing subglottic space widening without tracheostomy; if this fails, tracheostomy becomes mandatory. 3
Surgical Decision Tree:
Anterior cricoid split: First-line for severe stenosis meeting criteria 1, 3
- Allows healing without tracheostomy placement
- Avoids speech development delays
Tracheostomy: If anterior cricoid split fails or patient doesn't meet criteria 1, 3
Anatomical categorization guides procedure selection 7:
- Isolated subglottic: Anterior cricoid split plus cartilage graft
- Subglottic and glottic or high subglottic: Anterior plus posterior cricoid split with cartilage graft
- Subglottic and tracheal: Cricotracheal resection with anastomosis
Laryngotracheal resection: Curative treatment of choice with very high long-term success rates and low perioperative morbidity/mortality 6
Acute Exacerbation Management
- Racemic epinephrine: Provides temporary relief for mild-to-moderate stenosis during upper respiratory infections by reducing superimposed edema 1, 3
- Systemic corticosteroids: Used early in stenosis course, though formal efficacy assessment lacking 1, 3
- No prophylactic antibiotics: Not indicated for prevention of subglottic stenosis in intubated patients 3
Prevention Strategies
For Intubated Neonates
- Appropriate endotracheal tube sizing: Tube size-to-gestational age ratio <0.1 prevents acquired stenosis 1, 3
- Minimize intubation duration: Intubation ≥7 days and ≥3 intubations are major risk factors 1
- Nasal CPAP alternative: Using nasal CPAP instead of intubation prevented all cases of subglottic stenosis in 201 premature infants 1
- Nasotracheal vs. orotracheal: Nasotracheal intubation associated with fewer reintubations 1
Critical Pitfalls to Avoid
- Do not use surgical dilation as first-line for actively inflamed GPA-associated stenosis—immunosuppression is superior 3
- Do not delay evaluation of postextubation stridor—it's a significant marker for moderate-to-severe stenosis 1, 3
- Do not prescribe prophylactic antibiotics for intubated patients—no data support this practice 3
- Do not assume endoscopic procedures are definitive—they have limited indications as primary procedures and often require repeated interventions 6, 7
- Tracheostomy should be last resort—only after other corrective means have been exhausted 2
Specialist Involvement
Management should involve an otolaryngologist or pulmonologist with expertise in subglottic stenosis lesions. 3