Quick Chart
  • Croup (acute laryngotracheobronchitis) is one of the more common childhood respiratory illnesses.
  • Croup is a viral inflammation of the upper airway, larynx, trachea and bronchi.
  • Symptoms present generally worse at night, peaking usually around 2AM to 3AM.

Read the complete article; Croup in the Medical Library > Pathophysiology.

 Clinical Presentation

Croup is a viral infection of the throat and trachea that causes some or all of the following:

  • Noisy breathing (stridor) – a high-pitched sound
  • Hoarse voice
  • Harsh- barking cough
  • Increased respiratory rate
  • Intercostal and supraclavicular recession
  • Tracheal tug
  • Nasal flaring
  • Fever
 Exclusion Criteria
Exclusion Criteria
 Risk Assessment
  • Steroids have been shown to decrease the severity of croup, reduce the length of hospital stay, need for nebulised Adrenaline and other interventions
  • Children with croup usually have a cold first; a runny nose, cough and slight temperature. The child then typically wakes during the night with a barking cough and difficulty breathing.
  • Do not delay transportation.
  • No superiority demonstrated with Dexamethasone over prednisolone 1,2
  • Croup is a clinical diagnosis based on history and physical exam. Severity of croup can be quantified via the Westley Croup Score, though, clinically it is not used to guide therapy. Instead, it is used to measure a patient’s response to therapy3.

Clinical Severity:

  • Barking cough
  • No stridor at rest
  • No sternal recession or tracheal tug
  • Normal behaviour
  • Barking cough
  • Audible stridor at rest
  • Mild sternal regression +/- tracheal tug
  • May be irritable at times
  • Persistent stridor at rest
  • Pallor and mottling
  • Severe sternal recession +/- tracheal tug
  • Drooling
  • Irritable or lethargic
Primary Care
Intermediate Care (EMT / Level 2)
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
Advanced Care (AP)
  • Mild to moderate croup: Oral Prednisolone without the need to use nebulised Adrenaline.
  • Severe croup with signs of severe respiratory distress: Nebulised Adrenaline then Prednisolone
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
  • Nebulised Adrenalinecan be repeated after 15 minutes4
Critical & Extended Care (CCP, PSO)
  • As per Advanced Care (AP) guidelines
 Additional Information
  • If no improvement, reconsider diagnosis (consider acute upper airway obstruction).


1. Fifoot AA, Ting JY. Comparison between single-dose oral prednisolone and oral dexamethasone in the treatment of croup: a randomized, double-blinded clinical trial. Emerg Med Australas. 2007 Feb;19(1):51-8. doi: 10.1111/j.1742-6723.2006.00919.x. PMID: 17305661.

2. Colin M. Parker, Matthew N. Cooper; Prednisolone Versus Dexamethasone for Croup: a Randomized Controlled Trial. Pediatrics September 2019; 144 (3): e20183772. 10.1542/peds.2018-3772

3. MedCALC Westley Croup Score retrieved via https://www.mdcalc.com/calc/677/westley-croup-score#evidence

4. Perth Children’s Hospital (2021) Emergency department guidelines: Croup retrieved via: https://pch.health.wa.gov.au/For-health-professionals/Emergency-Department-Guidelines/Croup

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