Stridor in Paediatric Age Group: Causes and Management

DEFINITION

CLASSIFICATION BY PHASE

CAUSES OF STRIDOR

A. Classification by Age

1. Neonates and Infants (<6 months) - Predominantly Congenital

2. Infants and Children (>6 months) - Predominantly Acquired

3. All Ages

• Acquired subglottic stenosis (post-intubation)
• Laryngeal/tracheal tumours
• Mediastinal masses compressing the trachea
• Bilateral vocal cord palsy (neurological)

B. Summary Box: Acute Paediatric Stridor

• Laryngomalacia, laryngeal web, subglottic stenosis

CLINICAL ASSESSMENT

History

• Age of onset: Congenital causes present early (birth/neonatal period); acquired causes typically in older infants/children
• Duration and progression: Acute = foreign body/infection; chronic = congenital anomaly
• Associated symptoms: Drooling (epiglottitis), barking cough (croup), choking episode (foreign body), hoarseness (glottic/subglottic pathology), weak cry (vocal cord palsy)
• Feeding difficulties and failure to thrive: Suggest significant obstruction (severe laryngomalacia, vascular ring)
• Vaccination status: Hib immunisation history is relevant for epiglottitis
• Perinatal history: Prematurity, NICU stay, prolonged intubation (subglottic stenosis risk)

Key Clinical Pointers by History

• Stridor with feeding/swallowing in first 4 weeks → vascular ring or TOF
• Biphasic stridor worsened by URTI → congenital subglottic stenosis
• Inspiratory stridor + drooling → acute epiglottitis
• Biphasic stridor without drooling → croup (Bailey & Love's)

Examination

• Position of comfort (tripod = epiglottitis), level of distress, use of accessory muscles
• DO NOT lay child down or insert spatula if drooling/stridulous - can precipitate respiratory arrest in epiglottitis
• Pulse oximetry is invaluable
• Look for cutaneous haemangioma (suggests subglottic haemangioma)
• Restlessness, tachycardia, and cyanosis = signs of hypoxia requiring urgent action

CROUP vs EPIGLOTTITIS: Differential Diagnosis

INVESTIGATIONS

1. Pulse oximetry - continuous monitoring mandatory
2. Plain X-rays:
   • Neck lateral: "thumb sign" (epiglottitis) vs "steeple sign" (croup)
   • Chest X-ray: foreign body, mediastinal mass, air-trapping
   • Only if child is stable; never send alone to radiology
3. Flexible nasendoscopy/fibreoptic laryngoscopy: Dynamic assessment; outpatient for laryngomalacia; confirms vocal cord paralysis
4. Rigid laryngoscopy + bronchoscopy under GA: Diagnostic and therapeutic; mandatory in bacterial tracheitis; for foreign body removal
5. Blood cultures: In suspected epiglottitis/bacterial tracheitis
6. Imaging (CT/MRI): For subglottic stenosis grading, vascular ring, or mediastinal mass

MANAGEMENT

General Principles (for all acute stridor)

• Keep child calm - anxiety worsens obstruction
• Do not agitate - avoid procedures/examinations that distress the child
• Supplemental oxygen - humidified, high-flow via mask (or blow-by in young infants)
• Upright positioning - sitting up reduces work of breathing
• Resuscitation trolley with equipment for emergency intubation and tracheostomy must be available
• Senior anaesthetic and ENT involvement early

1. Laryngomalacia

• Mild (90% of cases): Reassurance; regular weight monitoring for failure to thrive; 4-week course of antireflux medication (GORD exacerbates symptoms)
• Severe cases (respiratory obstruction, failure to thrive): Surgical - supraglottoplasty (division of shortened aryepiglottic folds, trimming of redundant supraglottic mucosa); laser or cold steel
• Most cases resolve by age 2 years (Scott-Brown's Otorhinolaryngology, Vol 2)

2. Croup (Viral Laryngotracheobronchitis)

• Mild: Oral/IM dexamethasone (0.15-0.6 mg/kg) or nebulised budesonide (2 mg); reduces oedema; improvement within 30 minutes
• Moderate-severe: Nebulised adrenaline (1 ml/kg of 1:1000, max 5 ml) with oxygen - provides short-term relief; monitor for 2-3 hours after (rebound effect)
• Severe (<5%): Intubation; tracheostomy rarely needed
• Humidification and observation; antibiotics only if secondary infection
• (Scott-Brown's, Vol 1)

3. Acute Epiglottitis

• Do NOT examine oropharynx - risk of laryngospasm and arrest
• Emergency intubation in controlled setting (operating theatre) - anaesthetist + ENT surgeon together; use sevoflurane inhalational induction; child sitting up
• Tracheostomy if intubation fails
• IV antibiotics: cefuroxime or ceftriaxone (covers H. influenzae)
• Blood cultures before antibiotics if possible
• Humidified oxygen, ICU monitoring
• Prevention: Hib conjugate vaccine has dramatically reduced incidence (Bailey & Love's)

4. Bacterial Tracheitis

• Direct laryngoscopy + bronchoscopy under GA - confirms pseudomembrane; pulmonary toilet mandatory
• Endotracheal intubation for several days (over 80% require intubation)
• Repeated endoscopic procedures almost always required for secretion clearance
• Broad-spectrum IV antibiotics (cover S. aureus including MRSA - vancomycin/clindamycin + anti-staphylococcal cover); adjust to cultures
• ICU nursing with vigilant care of ETT (high risk of secretion occlusion)
• (Scott-Brown's, Vol 2; Bailey & Love's)

5. Foreign Body Aspiration

• Rigid bronchoscopy under GA - definitive treatment; foreign body removal with appropriate forceps
• High-flow oxygen while awaiting procedure
• Do NOT perform blind finger sweeps
• Pre-procedure chest X-ray (AP + lateral, inspiratory + expiratory views)
• Tracheobronchoscopy is both diagnostic and curative

6. Subglottic Stenosis

• Graded by Myer-Cotton classification (Grade I-IV)
• Grade I-II: Endoscopic management - balloon dilation laryngoplasty, CO₂ laser, or anterior cricoid split
• Grade III-IV (severe): Open surgery - laryngotracheoplasty (cartilage grafting) or cricotracheal resection
• Temporary tracheostomy may be required while reconstruction heals

7. Subglottic Haemangioma

• Systemic propranolol - now first-line treatment (reduces size and vascularity)
• Intralesional steroid injection / CO₂ laser excision (historical)
• Tracheostomy if airway compromised while awaiting medical treatment response

8. Retropharyngeal/Peritonsillar Abscess

• IV antibiotics (ampicillin-sulbactam or clindamycin)
• Surgical drainage - incision and drainage under GA once airway secured
• ENT + anaesthetic joint management of airway

9. Vocal Cord Paralysis

• Unilateral: Often watchful waiting; speech therapy; spontaneous recovery possible
• Bilateral (life-threatening): Tracheostomy initially; later lateralisation procedures (arytenoidectomy, cordotomy)

10. Recurrent Respiratory Papillomatosis

• Repeated microlaryngoscopy + debulking (cold steel, CO₂ laser, or microdebrider)
• Adjuvant: intralesional cidofovir, interferon alpha, bevacizumab (promising)
• HPV vaccine may reduce future incidence

SURGICAL AIRWAY (Tracheostomy)

• Failed intubation
• Prolonged intubation anticipated (bacterial tracheitis, bilateral VCP)
• As a bridge to reconstructive surgery (severe SGS)
• Permanent airway protection (bilateral vocal cord palsy)

SUMMARY TABLE: Quick Reference