Stridor (peds)

This page is for pediatric patients. For adult patients, see: stridor

Background

Cross section of a trachea and esophagus anatomy.
Tracheal anatomy.
  • Stridor refers to harsh upper airway sounds caused by turbulent airflow through a narrowed airway[1]
  • Classically inspiratory, indicating extrathoracic obstruction
  • Pediatric airways are particularly vulnerable due to anatomical differences:
    • Smaller absolute airway diameter — 1mm of circumferential edema reduces cross-sectional area by ~60% in an infant vs. ~20% in an adult
    • More compliant airway cartilage
    • Relatively larger tongue and occiput
  • Croup is the most common cause of acute stridor in children ages 6 months to 6 years[2]
  • A minimal amount of edema or inflammation can result in significant obstruction and rapid decompensation

Clinical Features

Phase of Respiration

  • Inspiratory stridor: extrathoracic obstruction (supraglottic/glottic)
  • Expiratory stridor (vs. wheezing): intrathoracic obstruction
  • Biphasic stridor: fixed obstruction (subglottic stenosis, hemangioma, foreign body lodged at glottis)

By Age

  • Neonates: laryngomalacia (most common cause of chronic stridor in infants), subglottic stenosis, vocal cord paralysis, congenital hemangioma, vascular ring
  • Infants (6 months - 2 years): croup, foreign body, laryngomalacia, subglottic hemangioma
  • Toddlers/Preschool (2-6 years): croup (most common), foreign body, epiglottitis, bacterial tracheitis
  • School-age and older: epiglottitis, peritonsillar abscess, retropharyngeal abscess, foreign body

Red Flags (Impending Respiratory Failure)

  • Drooling, inability to swallow
  • Tripod positioning, refusal to lie down
  • Toxic appearance, high fever (epiglottitis, bacterial tracheitis, retropharyngeal abscess)
  • Cyanosis, altered mental status, decreasing stridor with worsening respiratory distress (exhaustion)
  • No cough + drooling + high fever = think epiglottitis (do NOT examine throat or agitate child)
  • Sudden onset without prodrome = think foreign body aspiration

Differential Diagnosis

Pediatric stridor

<6 Months Old

  • Laryngotracheomalacia
    • Accounts for 60%
    • Usually exacerbated by viral URI
    • Diagnosed with flexible fiberoptic laryngoscopy
  • Vocal cord paralysis
    • Stridor associated with feeding problems, hoarse voice, weak and/or changing cry
    • May have cyanosis or apnea if bilateral (less common)
  • Subglottic stenosis
    • Congenital vs secondary to prolonged intubation in premies
  • Airway hemangioma
    • Usually regresses by age 5
    • Associated with skin hemangiomas in beard distribution
  • Vascular ring/sling

>6 Months Old

  • Croup
    • viral laryngotracheobronchitis
    • 6 mo - 3 yr, peaks at 2 yrs
    • Most severe on 3rd-4th day of illness
    • Steeple sign not reliable- diagnose clinically
  • Epiglottitis
    • H flu type B
      • Have higher suspicion in unvaccinated children
    • Rapid onset sore throat, fever, drooling
    • Difficult airway- call anesthesia/ ENT early
  • Bacterial tracheitis
    • Rare but causes life-threatening obstruction
    • Symptoms of croup + toxic-appearing = bacterial tracheitis
  • Foreign body (sudden onset)
    • Marked variation in quality or pattern of stridor
  • Retropharyngeal abscess
    • Fever, neck pain, dysphagia, muffled voice, drooling, neck stiffness/torticollis/extension

Evaluation

Immediate

  • Assess airway stability — allow child to remain in position of comfort (parent's lap)
  • Do NOT agitate the child if epiglottitis is suspected
  • Pulse oximetry (may be normal until late)
  • Observe work of breathing, air entry, level of consciousness

Stable Patient

  • AP and lateral neck X-rays:
    • Steeple sign (subglottic narrowing) = croup
    • Thumbprint sign (swollen epiglottis) = epiglottitis
    • Prevertebral soft tissue widening = retropharyngeal abscess
    • Radiopaque foreign body
  • CT neck with contrast if deep space infection, abscess, or mass suspected
  • Direct visualization (nasopharyngoscopy / fiberoptic laryngoscopy) if available and safe

Unstable Patient

Laboratory

  • Not routinely helpful in acute setting
  • CBC, blood cultures if bacterial cause suspected (bacterial tracheitis, epiglottitis)
  • Avoid phlebotomy in a distressed child with epiglottitis (agitation worsens obstruction)

Management

Croup (Most Common)

  • Dexamethasone 0.6 mg/kg PO/IM (single dose, max 10mg) — cornerstone of treatment, effective even in mild croup
  • Racemic epinephrine (2.25%) 0.5 mL nebulized in 3 mL NS for moderate-severe croup
    • Or L-epinephrine (1:1000) 0.5 mL/kg nebulized (max 5 mL)
    • Observe for 2-3 hours after racemic epinephrine (rebound possible)
  • Humidified air/mist therapy: no proven benefit but commonly used
  • Heliox for severe croup not responding to above

Epiglottitis

  • Keep child calm, in parent's lap, in position of comfort
  • Do NOT examine throat, do NOT lay child down, do NOT insert tongue depressor
  • Call anesthesia and ENT immediately
  • Controlled intubation in the operating room (preferred)
  • If impending arrest: attempt intubation with experienced provider, prepare for surgical airway
  • IV antibiotics after airway secured: ceftriaxone + vancomycin

Bacterial Tracheitis

  • Intubation often required (thick tracheal secretions)
  • IV antibiotics: ceftriaxone + vancomycin (or nafcillin)
  • Frequent suctioning

Foreign Body

  • If complete obstruction: BLS choking algorithm (back blows for infants, Heimlich for older children)
  • If partial obstruction with stable airway: bronchoscopy for removal (do not attempt blind finger sweep)
  • If unstable: attempt direct laryngoscopy for removal

Retropharyngeal/Peritonsillar Abscess

Anaphylaxis

Disposition

Admit / PICU

  • Epiglottitis (PICU with secured airway)
  • Bacterial tracheitis
  • Severe croup not responding to treatment
  • Required >1 dose of racemic epinephrine and still symptomatic
  • Deep space neck infections
  • Foreign body requiring bronchoscopy
  • Respiratory failure or impending failure

Discharge

  • Mild croup responding to dexamethasone with no stridor at rest after 2-3 hours observation
  • Single dose of racemic epinephrine with resolution of symptoms after 2-3 hour observation period
  • Reliable caregivers with access to return to ED
  • Return precautions: worsening stridor, drooling, difficulty breathing, color change, inability to drink fluids, fever

See Also

External Links

References

  1. ↑ Ida JB, Thompson DM. Pediatric stridor. Otolaryngol Clin North Am. 2014 Oct;47(5):795-819. PMID 25213283
  2. ↑ Zalzal HG, Zalzal GH. Stridor in the Infant Patient. Pediatr Clin North Am. 2022 Apr;69(2):301-317. PMID 35337541
Retrieved from "https://www.wikem.org/w/index.php?title=Stridor_(peds)&oldid=389704"