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Croup – Emergency

Croup – Emergency management in children

Key points

  • Croup is a common cause of airway obstruction in young children.
  • Symptoms are usually mild-moderate (worse at night and peak on day 2-3) and self-limiting but can be severe and rarely, life-threatening.
  • Care should be taken to avoid distressing a child with croup as this may exacerbate symptoms.
  • Treatment includes corticosteroids and, in moderate to severe cases, nebulised adrenaline.


This document provides clinical guidance for all staff involved in the care and management of a child presenting to an Emergency Department (ED) with symptoms suggestive of croup in Queensland.

This guideline has been developed by senior ED clinicians and Paediatricians across Queensland, with input from PICU and ENT staff, Lady Cilento Children’s Hospital, Brisbane. It has been endorsed for use across Queensland by the Statewide Emergency Care of Children Working Group in partnership with the Queensland Emergency Department Strategic Advisory Panel and the Healthcare Improvement Unit, Clinical Excellence Division.


Croup (acute laryngotracheobronchitis) is a clinical syndrome characterised by barking cough, inspiratory stridor and hoarseness of voice with or without respiratory distress.1,2 It is a common cause of upper airway obstruction in young children, accounting for approximately 2.3% of ED presentations in Australia and New Zealand.3,4 Although croup is usually a mild and self-limiting illness, significant upper airway obstruction, respiratory distress, and rarely death, can occur.4

Croup results from inflammation of the upper airway, including the larynx, trachea, and bronchi. Viral invasion of the laryngeal mucosa leads to inflammation, hyperaemia, and oedema. This may subsequently result in narrowing of the subglottic region.5 Children then compensate for this narrowing by changing their work of breathing.

In children with severe croup, as the narrowing progresses their increased work of breathing becomes counter-productive. Airflow through the upper airway becomes turbulent (producing stridor) and their compliant chest wall begins to cave in during inspiration.6-8 This results in paradoxical breathing, and consequently the child becomes fatigued. If untreated, these events may lead to hypoxia and hypercapnea, which may eventually result in respiratory failure and arrest.6-8

Typical viral croup develops over a few days with a concurrent coryzal illness. Many viruses may cause croup, the most common of which are Parainfluenza and RSV.1,2,4,9,10 The airway obstruction symptoms of croup are classically worse at night and peak on the second or third night of the illness. Symptoms usually resolve within 48 hours but occasionally persist for up to a week.1,2,11,12

  • ALERT – Children with croup should be made as comfortable as possible, and clinicians should take special care during assessment and treatment not to distress the child as this may cause substantial worsening of symptoms.


Children with a variety of conditions may present with acute onset stridor and respiratory distress and may have a range of associated symptoms and varying levels of severity.13 The first step in any assessment is to consider the differential diagnosis of an acute episode of stridor (see table below).

Croup mostly affects children between 6 and 36 months, although it may occur in older children or infants as young as 3 months.10 It is rare beyond 6 years of age.5,14 Alternative causes of upper airway obstruction should be considered and excluded in all children presenting with symptoms of upper airway obstruction but particularly those outside the typical age range. Always consider the possibility of foreign body inhalation in young children.

Differential diagnosis of acute onset stridor and respiratory distress
Toxic appearance* Non-toxic appearance
  • Bacterial tracheitis
  • Epiglottitis
  • Retropharyngeal abscess
  • Peritonsillar abscess (quinsy)
  • Spasmodic croup
  • Angioneurotic oedema
  • Laryngeal foreign body
  • Subglottic haemangioma

*Child who looks unwell and has reduced interaction with their environment14
Adapted from the NSW Department of Health Clinical Practice Guidelines15 and Royal Children’s Hospital, Melbourne16

Once confident in the diagnosis of croup, an accurate assessment (mild, moderate, severe and life-threatening) of severity is important to guide treatment. Croup severity scores used in hospital-based clinical research studies are of limited value in clinical practice.17 The initial assessment of a child presenting with croup should be based on the Alberta Medical Association Guideline as outlined in table below (developed as a clinical adaption of the research based Westley Croup score).15, 18 Throat examination is not recommended as distress may exacerbate symptoms.

Assessment of severity of croup
Mild Moderate Severe Life-threatening
Occasional barking cough

No audible stridor at rest

Frequent barking cough

Audible stridor at rest

Persistent stridor at rest (may be expiratory) Audible stridor may be quieter
No or mild respiratory distress* at rest Moderate respiratory distress Severe respiratory distress Exhausted, poor respiratory effort
Normal SpO2 #

No cyanosis

Normal SpO2

No cyanosis

SpO2 ≤93% or


SpO2 ≤93% or


Alert Little or no agitation Fatigue or altered mental state Lethargy or decreased level of consciousness

*Signs of respiratory distress include accessory muscle use, abdominal breathing, intercostal recession, subcostal recession and tracheal tug.
#Oxygen saturations using pulse oximetry, commonly referred to as “sats”
Adapted from: Alberta Medical Association Guideline as referenced in Cherry17

  • Consider seeking senior emergency/paediatric advice as per local protocols for child with moderate to severe croup.
  • Seek senior emergency/paediatric advice as per local protocols for a child with moderate to severe croup who is not responding to treatment.
  • Contact paediatric critical care specialist (onsite or via RSQ) for a child with life-threatening croup. Urgent onsite assistance to manage airway may include ICU/ENT/Anaesthetics.

Risk factors for severe croup include:

  • age < 6 months
  • underlying structural upper airway condition e.g. tracheomalacia, subglottic stenosis
  • history of previous severe croup
  • unplanned representation to ED within 24 hours of first croup presentation
  • trisomy 21


Investigations (including blood tests, NPA, CXR) are usually not indicated and may unnecessarily upset the child and worsen symptoms. Lateral X-ray of the neck is not routinely required and seldom provides information that affects management.17 Although subglottic narrowing, radio-opaque foreign bodies and supraglottic swelling may be apparent on radiographic imaging of the airway, the risk of the procedure generally outweighs any benefits, as neck extension required for the procedure may precipitate sudden severe obstruction.17


Refer to flowchart for a summary of the emergency management for children presenting with symptoms of croup.

There is no definitive treatment for the viruses that cause croup. Therapy is aimed at decreasing airway oedema and providing supportive care (respiratory support and maintenance of hydration). Care should be taken to avoid causing distress in the child as this can exacerbate symptoms.

Recommended management includes:

  • the appropriate use of corticosteroids and nebulised adrenaline.19-24 These interventions have been shown to reduce the need for, and duration of endotracheal intubation, length of stay, and representation rates to emergency services.19,20,22,25,26
  • nursing the child upright on carer’s lap


Corticosteroids take approximately 30 minutes to lessen respiratory distress,27 more quickly if given by nebuliser.19,22 The precise mechanism by which corticosteroids exert their effect is not fully known. It is presumed to be based on vasoconstrictive actions in the upper airway followed by the systemic anti-inflammatory effect.

Oral administration is recommended whenever possible. Advantages of oral over other methods include:

  • less pain and distress for the child
  • inexpensive and readily available
  • easy to administer 2,21,28
Steroid dosing for the treatment of croup in children
Dexamethasone (PO/IM) 0.15-0.3 mg/kg

May use up to 0.6 mg/kg if repeat doses required or to ensure the desired dose in child who is resistant to taking oral medicine.

Preferred corticosteroid as associated with lower representation rate.30, 31

Not available at all hospitals and community pharmacies.

Prednisolone (PO) Day 1: 1mg/kg/day

Day 2: 1mg/kg/day in evening29

Nebulised budesonide

Nebulised budesonide may be considered if the child repeatedly vomits the oral medication.

Budesonide (NEB) dosing for the treatment of croup in children
Dose 2mg nebulised with oxygen.
Side effects Facial irritation – cover child’s eyes while administering and wash face afterwards32

Nebulised adrenaline

  • Contact paediatric critical care specialist (onsite or via RSQ) for a child who fails to respond to nebulised adrenaline.

Immediate treatment with nebulised adrenaline should be considered in any child with persisting inspiratory stridor (at rest) and marked chest wall retractions (moderate to severe croup).  Adrenaline is thought to reduce bronchial and tracheal epithelial vascular permeability thereby decreasing airway oedema, resulting in an increase in the airway radius and improved airflow.2,19 

Nebulised adrenaline is associated with significant transient reduction of symptoms of croup 30 minutes post-treatment.34 The duration of effect is approximately 2 hours.1,2,33,34

Adrenaline (NEB) dosing for the treatment of croup in children
Dose 5 mL of undiluted 1:1000 adrenaline nebulised with oxygen

Dose may be repeated if there is inadequate response.29

Monitoring Clinical observations every 15 minutes for the first hour.

Historically, children were admitted for 24 hours after an initial dose of nebulised adrenaline. However, 2 retrospective cohort studies and combined data from 5 prospective clinical trials in croup patients treated with adrenaline and dexamethasone (or budesonide) and observed for 2-4 hours, found that fewer than 5% of children discharged home returned within 72 hours (with only 6/253 requiring admission).23,35-38 There were no reported adverse events. Based on this evidence and allowing a margin of safety, discharge may be considered 3 hours after nebulised adrenaline providing the child has tolerated an effective dose of systemic steroids and symptoms (stridor and/or respiratory distress) have not persisted or recurred. If a repeat dose of adrenaline is required the 3 hours must be taken from the time of the second dose.39 In practice, the decision to discharge will also depend on non-clinical factors including the time of day and the family’s proximity to hospital.

Other Treatments

Supplemental oxygen therapy is not routinely recommended. It may be considered in children with severe viral croup who have significant oxygen desaturation (SpO2 <93%), however this must be administered with care to avoid further distressing the child. Oxygen may be administered without distressing the child via a plastic tubing with the opening held within a few centimetres of the nose and mouth (blow-by oxygen) at minimum of 10L/min flow rate.14 For life-threatening croup, administer high flow oxygen at 15 L/min via non-rebreather mask.

  • ALERT – Oxygen desaturation may herald an impending complete upper airway obstruction.

Treatments which are NOT recommended for acute croup include:

  • antibiotics
  • steam inhalations38,39 (as insufficient evidence to support use and carry risk of scalds and burns in young children)40
  • heliox treatment (RCT evidence (n=91) to suggest a significant improvement in croup scores at 60 minutes but not after 120 minutes). However, individual clinicians may consider its use in refractory cases of moderate or severe croup.

When to escalate care

Follow your local facility escalation protocols for children of concern. Transfer is recommended if the child requires care beyond the level of comfort of the treating hospital. Clinicians can contact the services outlined below to escalate the care of a paediatric patient.

Service Reason for contact by clinician Contact
Local Paediatric service For specialist paediatric advice and assistance with local transfers as per local arrangements. As per local arrangements
Children’s Advice and Transport Coordination Hub (CATCH) For access to specialist paediatric advice and assistance with inter-hospital transfer of non-critical patients into and out of Lady Cilento Children’s Hospital.

For assistance with decision making regarding safe and appropriate inter-hospital transfer of children in Queensland.

For QH staff, click here for further information including the QH Inter-hospital transfer request form (access via intranet).

(07) 3068 4510

CATCH website

24 hours

Telehealth Emergency Management Support Unit (TEMSU) For access to generalist and specialist acute support and advice via videoconferencing, as per locally agreed pathways, in regional, rural and remote areas in Queensland.

For QH staff, click here for further information (access via intranet).


24 hours

Retrieval Services Queensland (RSQ) For access to telehealth support for, and to notify of, critically unwell patients requiring retrieval in Queensland.

For any patients potentially requiring aeromedical retrieval or transfer in Queensland.

For QH staff, click here for further information and relevant forms (access via intranet).

RSQ QHEPS website

24 hours


When to consider discharge

Most children with appropriately diagnosed croup will be discharged from the ED.

Discharge is recommended for children with croup who meet the following criteria:

  • no respiratory distress or stridor at rest post treatment (minimum 3 hours post nebulised adrenaline or 1-hour post oral steroids)
  • croup remains the primary diagnosis after consideration of differential diagnoses
  • parents have:
    • access to further doses of any required prescribed medication
    • received education regarding the condition and are comfortable with what to do if symptoms recur (provide Croup Factsheet)
    • access to transport or emergency services


  • with General Practitioner in 1 -2 days

When to consider admission

Facilities without a Short Stay Unit (SSU)

Admission is recommended for children with croup who have persistent or recurrent symptoms (stridor and/or respiratory distress) despite treatment at 3 hours.

Consider admission for the following children with croup:

  • those at high risk of severe illness. This includes:
    • age < 6 months
    • underlying structural upper airway condition
    • history of previous severe croup
    • trisomy 21
    • unplanned representation to ED within 24 hours following diagnosis of croup at first presentation
  • persistence of symptoms (e.g. respiratory distress or stridor at rest) 3 hours after treatment
  • inadequate fluid intake
  • children with social circumstances that make discharge potentially unsafe

Facilities with a Short Stay Unit (SSU)

Consider admission to an SSU for children who are responding to treatment but require a period of observation prior to meeting the criteria for discharge.

When to consider admission to inpatient ward from SSU

Consider admission to an inpatient service should for children who are failing to improve (persistent/recurring or worsening symptoms) after 12 hours of care.

Related documents


  1. Fitzgerald DA., Mellis C.M. Management of acute upper airways obstruction in children. Modern Medicine of Australia. 1995; 38: 80-88.
  2. Klassen TP. Croup: A current perspective in emergency medicine. Pediatric Clinics of North America. 1999; 46 (6): 1167-1178.
  3. Acworth J., Babl F., Borland M., et al. Patterns of presentations to the Australian and New Zealand paediatric emergency research network. Emergency Medicine Australasia. 2009; 21 (1): 59-66.
  4. Segal AO., Crighton EJ., Moineddin R., et al. Croup hospitalizations in Ontario: A 14-year time-series analysis.  Pediatrics. 2005; 116 (1): 51-55.
  5. Cherry JD., Feigin RD. Textbook of paediatric infectious diseases. 3rd ed. Philadelphia (USA): WB Saunders Company; 2006.
  6.  Johnson D. Clinical evidence: Croup [internet]. Clinical Evidence website; 2009 [cited 2011 May 10]. Available from:
  7. Davis G. An examination of the physiological consequences of chest wall distortion in infants with croup. Calgary (CA): University of Calgary; 1985.
  8. Davis G., Cooper D., Mitchell I. The measurement of thoraco-abdominal asynchrony in infants with severe laryngotracheobronchitis. Chest. 1993; 103 (6): 1842–1848.
  9. Peltola V., Heikkinen T., Ruuskanen O. Clinical courses of croup caused by influenza and parainfluenza viruses.  Pediatric Infectious Diseases Journal. 2002; 21(1): 76-78.
  10. Denny FW., Murphy TF., Clyde WA., et al. Croup: an 11-year study in a pediatric practice. Pediatrics. 1983; 71 (6); 871-876.
  11. Skolnik NS. Treatment of Croup: a critical review. American Journal of Diseases of Children. 1989; 143 (9): 1045-9.
  12. Johnson DW., Williamson J. Croup: duration of symptoms and impact on family functioning. Pediatric Research.  2001; 49: 83A.
  13. Majumdar S, Bateman NJ, Bull PD. Paediatric Stridor. 2006. BMJ Best Practice. PDF
  14. Bjornson CL., Johnson DW. Croup. The Lancet. 2008; 371 (9609): 329-339.
  15. Children and Infants – Acute Management of Croup . NSW Health Website; 2010 { cited 2017 July 3) Available from:
  16. Royal Children’s Hospital, Melbourne. Croup (Laryngotracheobronchitis) [internet]. Royal Children’s Hospital, Melbourne website; 2017 [cited 2017 July 3]. Available from:
  17. Fitzgerald DA., Kilham HA. Croup: Assessment and evidence-based management. Medical Journal of Australia.  2003; 179 (7): 372 – 377.
  18. Cherry JD. Croup. The New England Journal of Medicine. 2008; 358 (4): 384-91.
  19. Fitzgerald DA., Mellis CM., Johnson M., et al. Nebulised budesonide as effective as nebulised adrenaline in moderately severe croup. Pediatrics. 1996; 97 (5): 722-725.
  20. Tibbals J., Shann FA., Landau LI. Placebo-controlled trial of prednisolone in children intubated for croup.  Lancet. 1992; 340 (8822): 745-748.
  21. Geelhoed GC., Macdonald WB. Oral dexamethasone in the treatment of croup: 0.15 mg/kg versus 0.3 mg/kg versus 0.6 mg/kg. Pediatric Pulmonology. 1995; 20 (6): 362-368.
  22. Klassen TP., Craig WR., Moher D., et al. Nebulized budesonide and oral dexamethasone for treatment of croup.  Journal of the American Medical Association. 1998; 279 (20): 1629-1632.
  23. Kelley PB., Simon JE. Racemic epinephrine use in croup and disposition. American Journal of Emergency Medicine. 1992; 10 (3): 181-183.
  24. Prendergast M., Jones JS., Hartman D. Racemic adrenaline in the treatment of laryngotracheitis: Can we identify children for outpatient therapy. American Journal of Emergency Medicine. 1994; 12 (6): 613-616.
  25. Jaffe D. The treatment of croup with glucosteroids. New England Journal of Medicine. 1998; 339 (8): 553-555.
  26. Cruz MN., Stewart G., Rosenberg N. Use of dexamethasone in the outpatient management of acute laryngotracheitis. Pediatrics. 1995; 96 (2 Pt 1): 220-223.
  27. Dobrovoljac M, Geelhoed GC. How fast does oral dexamethasone work in mild to moderately severe croup? A randomized double-blinded clinical trial. Emergency Medicine Australasia 2012;24(1):79–85.
  28. Ausejo M., Sanez A., Pham B., et al. The effectiveness of glucosteroids in treating croup: meta-analysis. British Medical Journal. 1999; 319 (7210): 595-600.
  29. Therapeutic Guidelines Ltd. Croup [internet]. Therapeutic Guidelines website; 2017 [cited 2017 July 3]. Available from:
  30. Sparrow A., Geelhoed G. Prednisolone vs. dexamethasone in croup: A randomised equivalence trial. Archives of Disease in Childhood. 2006; 91 (7): 580-583.
  31. Fifoot AA., Ting JY. Comparison between single-dose oral prednisolone and oral dexamethasone in the treatment of croup: a randomized, double-blinded clinical trial. Emergency Medicine Australasia. 2007; 19 (1): 51-58.
  32. Waiisman Y., Klein BL., Boenning DA., et al. Prospective randomised double-blind study compairing L-epinephrine aerosols in the treatment of laryngotracheitis (croup). Pediatrics. 1992; 89 92): 302-306.
  33. Johnson D., Jacobson S., Edney P., et al. A comparison of nebulized budesonide, intramuscular dexamethasone, and placebo for moderately severe croup. New England Journal of Medicine. 1998; 339 (8): 498:503.
  34. Bjornson C, Russell K, Vandermeer B, Klassen TP, Johnson DW. Nebulized epinephrine for croup in children. Cochrane Database of Systematic Reviews 2013, Issue 10. Art. No.: CD006619.
  35. Rizos J., DiGravio B., Sehl M., et al. The disposition of children with croup treated with racemic epinephrine and dexamethasone in the emergency department. The Journal of Emergency Medicine. 1998; 16 (4): 535–539.
  36. Ledwith C., Shea L., Mauro R. Safety and efficacy of nebulized racemic epinephrine in conjunction with oral dexamethasone and mist in the outpatient treatment of croup. Annals of Emergency Medicine. 1995; 25 (3): 331-7.
  37. Kunkel N., Baker M. Use of racemic epinephrine, dexamethasone and mist in the outpatient management of croup. Pediatric Emergency Care. 1996; 12 (3): 156-159.
  38. Moore M., Little P. Humidified air inhalation for treating croup. Cochrane Database of Systematic Reviews. 2006; Issue 3, Art. No.: CD002870.
  39. Rudinsky, SL et al. Inpatient Treatment after Multi-Dose Racemic Epinephrine for Croup in the Emergency Department The Journal Of Emergency Medicine [J Emerg Med] 2015 Oct; Vol. 49 (4), pp. 408-14.
  40. Weber JE., Chudnofsky CR., Younger JG., et al. A randomised comparison of helium-oxygen mixture (heliox) and racemix epinephrine for the treatment of moderate to severe croup. Pediatrics. 2001; 107(6): e96.
  41. Greally P., Cheng K., Tanner M., et al. Children with croup presenting with scalds. British Medical Journal. 1990; 301 (6743): 113.

Guideline approval

Guideline approval history
Document ID CHQ-GDL-60004-Croup Version no. 1.0 Approval date 13/8/18
Executive sponsor Executive Director Medical Services Effective date 13/8/18
Author/custodian Statewide Emergency Care Children Working Group Review date 13/8/21
Supersedes CHQ-GDL-00702
Applicable to Queensland Health medical and nursing staff
Authorisation Executive Director Clinical Services LCCH
Keywords Paediatric, emergency, guideline, croup, children, 60004
Accreditation references NSQHS Standards (1-10): 1, 4, 9


This guideline is intended as a guide and provided for information purposes only. View full disclaimer.
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