Croup

Background

  • Also known as laryngotracheobronchitis
  • Typically affects ages 6 mo-3 yr (peak in 2nd year)
    • May affect older children
    • Most common in fall & winter

Etiologies

  • Parainfluenza (50% - 75%)
  • Influenza A and B (usually more severe clinical picture)
  • RSV
  • Spasmodic croup
    • Sudden onset of barking cough/stridor
    • No viral prodrome, unlike typical croup
    • Difficult to differentiate from typical croup
  • Must rule out foreign body

Clinical Features

  • 1-3 days of URI symptoms, followed by barking cough, hoarse voice, and stridor
  • Low-grade fever
  • NO drooling or dysphagia
  • Duration 4 - 7 days
    • Usually most severe on days 3-4

Mild[1]

  • 85% of cases
  • Intermittent barking cough
  • Stridor with agitation
  • Mild tachypnea
  • Mild tachycardia

Moderate[2]

  • Fussy but alert, interactive, consolable by parents
  • Stridor at rest
  • Worsening stridor with agitation
  • Increased work of breathing

Severe[3]

  • Hypoxia
  • Less than 1% of cases

Differential Diagnosis

Pediatric stridor

  • A minimal amount of edema or inflammation in the pediatric airway can result in significant obstruction
    • Can lead to rapid decompensation

<6mo

  • Laryngotracheomalacia
    • Accounts for 60%
    • Usually exacerbated by viral URI
    • Dx w/ flexible fiberoptic laryngoscopy
  • Vocal cord paralysis
    • Stridor associated w/ feeding problems, hoarse voice, weak and/or changing cry
    • May have cyanosis or apnea if bilateral (less common)
  • Subglottic stenosis
    • Congenital vs 2/2 prolonged intubation in premies
  • Airway hemangioma
    • Usually regresses by age 5
    • Associated w/ skin hemangiomas in beard distribution
  • Vascular ring/sling

>6mo

  • 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
    • Sx 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

Work-up

The steeple sign as seen on an AP neck X-ray (dedicated neck film not typically indicated).
  • Consider CXR if concerned about alternative diagnosis
    • In typical cases, imaging is not needed and does not change management
    • Steeple sign on AP XR (not specific or sensitive)
  • Consider nasal pharyngeal swab

Diagnosis

  • Clinical
    • Steeple sign unreliable

Westley Croup Score[4][5]

Helps to stratify patients into mild moderate and severe and guide treatment

Westley score: Classification of croup severity
Feature Number of points assigned for this feature
0 1 2 3 4 5
Chest wall retraction None Mild Moderate Severe
Stridor None With agitation At rest
Cyanosis None With agitation At rest
Level of consciousness Normal Disoriented
Air entry Normal Decreased Markedly decreased

Assessment

  • <2 Very mild
  • 2-6 Mild to moderately severe
  • 7-11 Severe croup
  • ≥ 12 Respiratory failure

Management

VEP Croup Care Pathway
  1. Cool mist
    • Humidified air may provide symptomatic treatment for patients with ongoing stridor[6]
  2. Steroids (first line treatment)
    • Dexamethasone 0.15-0.6mg/kg PO/IM (max 10mg)[7][8]
    • No differences between intramuscular and oral dexamethasone [9]
    • Onset 6 hrs, duration 72 hrs
  3. Epinephrine (nebulized)
    • Use in moderate to severe cases based on the croup scores. Use either Racemic or Standard Epinephrine[10]
    • Symptomatic relief via local vasoconstriction
    • Racemic Epi (2.25%): 0.05 mL per kg (maximal dose: 0.5 mL) of racemic epinephrine 2.25% [11]
    • Epinephrine(1:1,000): 0.5 mL per kg (maximal dose: 5 mL) via nebulizer
    • Onset up to 30 min, duration 2 hrs
    • Watch child 2-3 hrs after administration to ensure no return of stridor at rest
  4. Intubation
    • Rarely needed but if so, use tube that is one half size smaller than normal for age/size of patient

Contraindicated

  • Do NOT give albuterol (may worsen edema (vasodilation))

No Evidence

  • Heliox
    • Mixture of helium and oxygen (with not less than 20% oxygen)
    • Low viscosity and low specific gravity facilitates laminar airflow through the respiratory tract.
    • Currently there is a lack of evidence to establish the effect of heliox inhalation in the treatment of croup in children[12]

Disposition

Consider Discharge if

  • 3hr since last epinephrine
  • Able to tolerate PO
  • Nontoxic appearance

Admit

  • Persistent respiratory symptoms/signs
  • ≥2 treatments with epinephrine

Video

See Also

External Links

References

  1. Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
  2. Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
  3. Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
  4. Westley CR, et al. Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study. Am J Dis Child. 1978; 132(5):484-487.
  5. Klassen TP, et al. Croup. A current perspective. Pediatr Clin North Am. 1999; 46(6):1167–1178.
  6. Scolnik D, Coates AL, Stephens D, Da Silva Z, Lavine E, Schuh S. Controlled delivery of high vs low humidity vs mist therapy for croup in emergency departments. JAMA. 2006;295(11):1274–1280
  7. Geelhoed GC, Macdonald WB. Oral dexamethasone in the treatment of croup: 0.15mg/kg versus 0.3mg/kg versus 0.6mg/kg. Pediatr Pulmonol. 1995;20(6):362–368.
  8. Bjornson, C.L., Klassen, T.P., Williamson, J., Brant, R., Mitton, C., Plint, A., Bulloch, B., Evered, L. and Johnson, D.W. (2004) ‘A Randomized trial of a single dose of oral dexamethasone for mild Croup’, New England Journal of Medicine, 351(13), pp. 1306–1313.
  9. Donaldson D, Intramuscular versus oral dexamethasone for the treatment of moderate-to-severe croup: a randomized, double-blind trial. Acad Emerg Med. 2003 Jan;10(1):16-21.
  10. Adair JC, Ring WH, Jordan WS, Elwyn RA. Ten-year experience with IPPB in the treatment of acute laryngotracheobronchitis. Anesth Analg. 1971;50(4):649–55
  11. Westley CR, Cotton EK, Brooks JG. Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study. Am J Dis Child. 1978;132(5):484–487
  12. Moraa I, Sturman N, McGuire T, van Driel ML., Heliox for croup in children., Cochrane Database Syst Rev. 2013 Dec 7;12:CD00682