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
- 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
- Viral
- Parainfluenza (50% - 75%)
- Influenza A and B (usually more severe clinical picture)
- RSV
- Rhinovirus, adenovirus
- Bacterial (Bacterial tracheitis)
- Same organisms as sinopulmonary infections: Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus [2]
- Consider Diphtheria if not immunized
- 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 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]
- 85% of cases
- Intermittent barking cough
- Stridor with agitation
- Mild tachypnea
- Mild tachycardia
Moderate[4]
- Fussy but alert, interactive, consolable by parents
- Stridor at rest
- Worsening stridor with agitation
- Increased work of breathing
Severe[5]
- Hypoxia
- Tachypnea and marked retractions
- Altered mental status
- Less than 1% of cases
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
- H flu type B
- 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
- Airway obstruction
- Structural
- Infectious
- Other
Cardiac
- Congenital heart disease
- Vascular ring
- Cardiac tamponade
- Congestive Heart Failure (peds)
- Myocarditis (peds)
Other diseases with abnormal respiration
- Normal neonatal periodic breathing (misinterpreted by caregivers as abnormal)
- Brief resolved unexplained event
- Anemia
- Abdominal distension (e.g. SBO, liver failure
- Neonatal abstinence syndrome
- Decreased perfusion states
- Metabolic acidosis
- CO Poisoning
- Diaphragm injury
- Renal Failure
- Electrolyte abnormalities
- Organophosphate toxicity
- Tick paralysis
- Fever (Peds)
- Panic attack
- Porphyria
Evaluation
Work-up
- 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
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
- Supplemental oxygen
- Consider utilizing blow-by oxygen to decrease agitation
- Humidified air may provide symptomatic treatment for patients with ongoing stridor[8]
- 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].
- 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
- 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
See Also
External Links
References
- ↑ 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.
- ↑ 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/
- ↑ Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
- ↑ Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
- ↑ Rose, E. (2018) Pediatric respiratory emergencies: Upper airway obstruction and infections. Rosen's Emergency Medicine (9th ed.) Philadelphia, PA: Elsevier/Saunders
- ↑ 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.
- ↑ Klassen TP, et al. Croup. A current perspective. Pediatr Clin North Am. 1999; 46(6):1167–1178.
- ↑ 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
- ↑ 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.
- ↑ 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.
- ↑ 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.
- ↑ Prednisolone versus dexamethasone for croup: a randomized controlled trial Parker CM, Cooper MN. Pediatrics. 2019;144(3):e20183772.
- ↑ 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
- ↑ 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
- ↑ Moraa I, Sturman N, McGuire T, van Driel ML., Heliox for croup in children., Cochrane Database Syst Rev. 2013 Dec 7;12:CD00682