Rosen & Barkin's 5-Minute Emergency Medicine Consult (182 page)

BASICS

• Viral infection of the upper respiratory tract
  
• Most commonly presents in children 6 mo–3 yr:
  
  • Laryngotracheitis/laryngotracheobronchitis
    
  • Inspiratory stridor owing to extrathoracic airway obstruction
    
  • Expiratory wheeze suggests lower airway involvement.
    
  • Inflammatory edema of subglottic region
    
  • Narrowest part of pediatric airway
    
• May progress to respiratory failure
  

• Parainfluenza types 1, 2, and 3
  
• Human coronavirus NL63
  
• Influenza A and B
  
• Adenoviruses
  
• Respiratory syncytial virus
  
• Measles
  
• Mycoplasma pneumoniae
  
• Herpes simplex
  

DIAGNOSIS

• Nonspecific upper respiratory prodrome with or without fever
  
• Duration of illness
  
• History of tracheal intubation
  
• Possibility of foreign body aspiration
  
• Previous episodes
  
• History of wheeze
  
• Immunization status (
  Haemophilus influenzae
  type b [HIB]; diphtheria, pertussis, and tetanus [DPT]), influenza
  

• Rarely toxic appearing
  
• Cyanosis (not present in majority of patients. If present, suggests severe disease)
  
• Prefer upright position
  
• Quality of cry/voice
  
• Drooling/trismus/limited
  neck extension
  
• Mental status
  
• Stridor at rest, increased work of breathing
  
• Hydration status
  
• Westley croup score (max. total points: 17):
  
  • Stridor (inspiratory or biphasic):
    
    • 0 = None
      
    • 1 = Audible with stethoscope at rest
      
    • 2 = Audible without stethoscope at rest
      
  • Retractions:
    
    • 0 = None
      
    • 1 = Mild
      
    • 2 = Moderate
      
    • 3 = Severe
      
  • Air entry:
    
    • 0 = Normal
      
    • 1 = Decreased
      
    • 2 = Severely decreased
      
  • Cyanosis:
    
    • 0 = None
      
    • 4 = With agitation
      
    • 5 = At rest
      
  • Level of consciousness:
    
    • 0 = Normal
      
    • 5 = Altered
      

• Continuous pulse oximetry
  
• Other tests are not routinely indicated.
  

Anteroposterior (AP) and lateral neck radiographs:

• Steeple sign indicates narrowing of subglottic trachea.
  
• Imaging not routinely indicated, unless atypical presentation or clinical course
  
• Subject to misinterpretation and should not be used as sole means to exclude epiglottitis
  
• Should not delay definitive visualization and intubation in OR in child with concern for epiglottitis or bacterial tracheitis
  
• Monitor child during imaging, if done.
  

• Infection:
  
  • Bacterial tracheitis
    
  • Retropharyngeal or parapharyngeal abscess
    
  • Epiglottitis
    
  • Peritonsillar abscess
    
  • Diphtheria
    
• Foreign body (airway or esophageal)
  
• Angioedema
  
• Congenital airway anomaly:
  
  • Laryngomalacia, tracheomalacia, laryngeal cleft
    
• Acquired subglottic stenosis
  
• Vocal cord paralysis
  
• Thermal or chemical injury to upper airway
  
• Hemangioma
  
• Laryngeal papillomatosis
  
• Vocal cord dysfunction (VCD) (adolescents)
  

TREATMENT

• Allow child to maintain position of comfort.
  
• Defer interventions that may distress child such as:
  
  • IV access
    
  • IM injections
    
• If severe distress:
  
  • Immediate nebulized epinephrine
    

• Nebulized racemic epinephrine or
  l
  -epinephrine if distress or stridor at rest:
  
  • l
    -epinephrine containing only the active isomer; has been shown to be therapeutically equivalent to racemic epinephrine
    
• Oxygen (via blow-by) for suspected or documented hypoxia suggesting severe disease
  
• Mist therapy often used, but no evidence for efficacy
  
• Dexamethasone:
  
  • Reduces need for intubation, shortens length of stay, and reduces admissions and return visits and may have effects within 30 min
    
  • Effective even in mild croup (Westley croup score ≤2)
    
• If poor response to nebulized racemic epinephrine or
  l
  -epinephrine:
  
  • Consider trial of heliox:
    
    • Heliox, when available, has been used to decrease the work of breathing in patients with an incomplete response to epinephrine.
      
• If impending or existing respiratory failure despite aforementioned therapy:
  
  • Tracheal intubation by most experienced person available
    
  • Use uncuffed endotracheal tube (ETT) 0.5--1 mm smaller than usual size.
    
• If epiglottitis or foreign body suspected:
  
  • Ideally, to OR for inhalational anesthesia, direct laryngoscopy, and intubation
    
  • Surgeon standing by for emergent tracheostomy
    

See “Initial Stabilization.”

• Racemic epinephrine 2.25%: 0.25–0.5 mL nebulized in 2.5 mL NS
  
• l
  -epinephrine 1:1,000: 5 mL (5 mg) nebulized
  
• Dexamethasone: Single dose of 0.6 mg/kg (max. 10 mg) PO (use crushed tablet) or IV preparation (4 mg/mL) PO with flavored syrup. Equally effective when given PO, IV, or IM. Lower doses may be effective.
  
• Heliox (70% helium: 30% oxygen mixture administered via face mask or tent house)
  
• Antibiotics: Not indicated
  

FOLLOW-UP

• Young infants, pre-existing upper airway obstruction
  
• Persistent or recurrent stridor at rest unresponsive to nebulized epinephrine, or recurring during 2–3 hr observation
  
• Pediatric intensive care unit:
  
  • Persistent severe obstruction
    
  • Need for frequent epinephrine treatments and/or heliox
    
  • Tracheal intubation with assisted ventilation
    

• Normal oxygenation in room air
  
• No stridor at rest after brief observation
  
• Children initially given epinephrine who no longer have stridor at rest should be observed for a min. of 2–3 hr
  
• Reliable caretaker, communication, and transport
  

• Concern for underlying anatomic abnormality (young age, history of intubation, frequent recurrence)
  
• Infants <1 year with stridor unassociated with laryngotracheobronchitis may require endoscopic evaluation
  

• Most children with croup do not require specific follow-up.
  
• Patients who have had prolonged stridor, or acute worsening of stridor should seek care with their primary care physician or return to the ED.
  

• Beware young infants with stridor
  
• High incidence of congenital abnormalities
  
• Mild and early epiglottitis or bacterial tracheitis may mimic croup
  

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• Cooper T, Kuruvilla G, Persad R, et al. Atypical croup: Association with airway lesions, atopy, and esophagitis.
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• Sung JY, Lee HJ, Eun BW, et. al. Role of human coronavirus NL63 in hospitalized children with croup.
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