Croup

Background

Cross section of a trachea and esophagus anatomy.
Tracheal anatomy.
  • Also known as laryngotracheobronchitis
  • Typically affects ages 6 mo-3 yr (peak in 2nd year)
    • May affect older children
    • Most common in fall & winter
    • 300k annual ED visits with significant hospitalization rates[1]
  • Pathophysiology: Infection leading to inflammation of any structure inferior to larynx, including larynx, trachea, or bronchi; swelling leads to airway obstruction and characteristic stridor and cough

Etiologies

Clinical Features

  • 1-3 days of nonspecific URI symptoms, followed by 3-4 days of "barking" cough, hoarse voice, stridor, and acute dyspnea
    • Usually most severe on days 3-4
  • Low-grade fever
  • Rarely drooling or dysphagia; consider alternate etiology if present

Mild[3]

Moderate[4]

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

Severe[5]

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

Pediatric Shortness of Breath

Pulmonary/airway

Cardiac

Other diseases with abnormal respiration

Evaluation

Work-up

The steeple sign as seen on an AP neck X-ray (dedicated neck film not typically indicated).
  • Typically a clinical diagnosis
  • Consider CXR if concerned about alternative diagnoses causing stridor
    • In typical cases, imaging is not needed and does not change management
    • Steeple sign (subglottic narrowing) on AP neck XR; note that this is not specific nor sensitive
  • Consider nasal pharyngeal swab for viral panel
  • IV insertion or other exam steps may lead to agitation and further airway obstruction


Westley Croup Score[6][7]

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. Supplemental oxygen
    • Consider utilizing blow-by oxygen to decrease agitation
    • Humidified air may provide symptomatic treatment for patients with ongoing stridor[8]
  2. Steroids
    • First-line treatment and standard of care for any severity of croup
    • Dexamethasone 0.15-0.6mg/kg PO/IV/IM (max 10mg)[9][10]
    • Typically one dose is sufficient
    • No differences between intramuscular and oral dexamethasone [11]
    • Onset 6 hrs, duration 72 hrs
    • Recent study showing non-inferiority of low dose (0.15mg/kg) dexamethasone and prednisolone at 1mg/kg[12].
  3. Nebulized Epinephrine
    • Use in moderate to severe cases based on the croup scores. Use either Racemic or Standard L-Epinephrine[13]
    • Symptomatic relief via local vasoconstriction
    • Racemic Epi (2.25%): 0.05 mL per kg (maximal dose: 0.5 mL) of racemic epinephrine 2.25% [14]
    • 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
    • Treatment may be repeated, but frequent dosing requires admission to ICU for cardiac monitoring
  4. Intubation
    • Rarely needed but if so, use tube that is one-half size smaller than normal for age/size of patient, considering the presumed upper airway edema

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[15]

Disposition

Consider Discharge if

  • 2-3hr since last epinephrine and no return of stridor at rest, remains well appearing
  • Able to tolerate PO
  • Nontoxic appearance

Admit

  • Persistent respiratory symptoms/signs
  • Inability to tolerate PO
  • ≥2 treatments with epinephrine

Video

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See Also

External Links

References

  1. Hanna J, Brauer PR, Morse E, Berson E, Mehra S. Epidemiological analysis of croup in the emergency department using two national datasets. Int J Pediatr Otorhinolaryngol. 2019 Nov;126:109641. doi: 10.1016/j.ijporl.2019.109641. Epub 2019 Aug 13. PMID: 31442871.
  2. Sizar O, Carr B. Croup. [Updated 2023 Jul 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK431070/
  3. Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
  4. Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
  5. Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
  6. 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.
  7. Klassen TP, et al. Croup. A current perspective. Pediatr Clin North Am. 1999; 46(6):1167–1178.
  8. 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
  9. 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.
  10. 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.
  11. 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.
  12. Prednisolone versus dexamethasone for croup: a randomized controlled trial Parker CM, Cooper MN. Pediatrics. 2019;144(3):e20183772.
  13. 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
  14. 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
  15. Moraa I, Sturman N, McGuire T, van Driel ML., Heliox for croup in children., Cochrane Database Syst Rev. 2013 Dec 7;12:CD00682