Croup is a viral illness with inflammation of the upper airway. It is also known as acute viral laryngo-tracheo-bronchitis.


  • Viral prodrome (1-2 days often mild corryzal symptoms)
  • Harsh barking cough
  • Hoarse voice and stridor
  • Fever less than 38 degrees
  • Stridor worse on crying and worse at night


  • Tachypnoea
  • Tachycardia
  • Sternal recession
  • Tracheal tug
  • Cyanosis on crying


  • Continuous harsh sound
  • Caused by obstruction in the larynx and trachea
  • Predominantly an inspiratory noise
  • Expiratory component may be present
    • ? subglottic lesion
  • Higher incidence in children than in adults (anatomical differences)

Differential diagnosis of stridor

  • Acute laryngo-tracheo-bronchitis(croup)
  • Acute epiglottitis
  • Bacterial tracheitis
  • Foreign body
  • Acute angioneurotic oedema(anaphylaxis)
  • Diphtheria
  • Expanding mediastinal mass
  • Tetany
  • Peritonsillar or retropharyngeal abscess

Croup management

Mild Croup

Indicators of increasing severity necessitating admission are:

  • Increasing respiratory rate
  • Increasing stridor
  • Diminished air entry on auscultation
  • Cyanosis at rest with oxygen saturation of less than 95% in air
  • Altered level of consciousness
  • General supportive measures, gentle handling and reassurance
  • Oral Dexamethasone (0.150 microgrammes /kg)

  • or
  • Nebulised Budesonide( 2mg)[BestBets]
  • Hydration should be assured by allowing the parents to feed the child
  • Investigation should be kept to a minimum
  • No lateral neck radiographs

Moderate to severe croup

  1. In the presence of increasing airway obstruction, it is imperative that the child is transferred to a paediatric facility
  2. Oxygen via either a nasal cannula or a face mask.
  3. Children often do not apply a face mask over their face but may well accept a mask held at a short distance above their face so that the oxygen plays across their nose and mouth.
  4. Children with

    • pre-existing narrowing of the upper airways (eg. subglottic stenosis congenital or 2° to neonatal ventilation) or
    • children with Down Syndrome

    are prone to more severe croup and admission should be considered even with mild symptoms

  5. Nebulised Adrenaline[Epinephrine] (5mls of 1 in 1,000) under close supervision with cardiac monitor (Stop if pulse > 200 bpm) or nebulised budesonide [BestBets].
  6. If nebulised Adrenaline has been given, intravenous access should be obtained and the anaesthetic team contacted to review and admission arranged.
  7. Steroids prescribed should include either nebulised budesonide or oral prednisonone [BestBets].
  8. Contact anaesthetic and paediatric departments for advice.

Content by, Dr Íomhar O' Sullivan 01/04/2004.  Reviewed by Dr Chris Luke 20/01/2005 & by Dr ÍOS 31/07/2007. Next review 31/07/2008