Synopsis
Recognise the barking-cough syndrome, grade upper-airway obstruction while keeping the child calm, give early corticosteroid and nebulised adrenaline when indicated, and distinguish croup from epiglottitis, bacterial tracheitis, anaphylaxis and an inhaled foreign body.
- Croup is viral subglottic inflammation, usually between 6 months and 6 years, causing a seal-like barking cough, hoarse voice and inspiratory stridor, often worse at night.
- Assess before touching: position, mental state, stridor at rest, recession, air entry, colour and hydration. Agitation worsens dynamic obstruction, so keep the child on the caregiver's lap.
- Mild croup has barking cough without stridor or recession at rest. Moderate disease has stridor and/or recession at rest without agitation or lethargy. Severe disease adds marked distress, agitation or lethargy.
- First-line medicine for croup of any clinically significant severity is a single oral dose of dexamethasone 0.15 mg/kg. Follow the product and local maximum; avoid delaying treatment for unnecessary tests.
- If oral medicine cannot be taken without dangerous distress or vomiting, nebulised budesonide 2 mg once is an accepted alternative in UK paediatric pathways.
- For severe or worsening obstruction, give nebulised adrenaline 1 mg/mL at 400 micrograms/kg, equivalent to 0.4 mL/kg, maximum 5 mg or 5 mL. Improvement is rapid but temporary.
- Observe after nebulised adrenaline under paediatric care because symptoms can recur as its effect wanes; repeat after senior review when severe obstruction persists and escalate the airway plan.
- Oxygen treats hypoxaemia but does not relieve the narrowing. Hypoxaemia in croup is a late, dangerous sign; deliver oxygen in the least upsetting manner.
- Do not routinely request radiographs, blood tests, swabs or arterial gases. Investigations can distress the child and are unnecessary in typical croup.
- Do not use steam: it lacks evidence and causes scalds. Avoid cough suppressants, sedatives, forced examination and unnecessary venepuncture.
- Do not inspect the pharynx when epiglottitis is possible. Maintain spontaneous breathing and involve anaesthesia and ENT for a controlled airway.
- Discharge only when stridor at rest and significant recession have resolved, the child drinks safely and caregivers understand recurrence and emergency signs.
Key red flags
Cyanosis, reduced consciousness, exhaustion, poor effort or reduced air entry indicates impending respiratory arrest even if stridor becomes quieter.
Drooling, dysphagia, muffled voice, tripod posture, absent bark and a toxic child suggests epiglottitis; do not examine the throat or distress the child.
High fever, toxic appearance, rapidly progressive obstruction and copious secretions suggests bacterial tracheitis and often requires airway control and intravenous antibiotics.
Abrupt onset during eating or play, focal air-entry change or no viral prodrome suggests an airway foreign body.
Urticaria, facial or tongue swelling, wheeze, hypotension or gastrointestinal symptoms with stridor suggests anaphylaxis and requires intramuscular adrenaline.
Age under 6 months, recurrent atypical episodes, persistent hoarseness or poor response warrants assessment for structural airway disease.
Investigation priorities
Diagnose typical croup and detect impending failure without worsening obstruction.
Management branches
Barking cough is present without stridor or recession at rest.
- Give oral dexamethasone 0.15 mg/kg once using the local product maximum.
- Confirm safe drinking and no feature of a dangerous alternative.
- Discharge with night-time recurrence, hydration and emergency breathing advice when context is safe.