Definition
Also called laryngotracheobronchitis, it is caused by an overactive immune response to the virus causing inflammation of the upper airways.
Etiology- Usually in children between 6 months and 3 years of age
- Commonly due to parainfluenza virus infection
- Prodromal phase
- 1-2 days
- Rhinitis, nasal congestion, low-grade fever ± red pharynx
- 1-2 days
- Inflammatory phase
- 2-7 days
- Barking cough, inspiratory stridor, widespread wheeze ± increase work of breathing ± fever
- Mild cases:
- Normal behaviour, normal RR, no O2 requirement, no/minimal accessory muscle use
- Barking cough ± stridor only when active or upset
- Moderate cases:
- Some irritability, moderate work of breathing, increase respiratory rate, no O2 required
- Barking cough + intermittent stridor at rest
- Severe cases:
- Irritable, lethargic, marked increase work of breathing, tachypnoea or bradypnoea (pre-terminal)
- Persistent stridor at rest, hypoxemia a late sign indicating significant obstruction (life-threatening)
- Usually a clinical diagnosis (no routine investigations)
- May consider CXR, FBE & culture to rule out DDx
- Minimal handling
- Mild-moderate cases: Dexamethasone 0.15mg/kg OR Prednisolone 1mg/kg PO
- Severe cases: nebulised adrenaline 0.5ml/kg 1:1000 (max 5ml) + IV/IM/PO dexamethasone 0.6mg/kg
- Life-threatening: nebulised adrenaline 5ml of 1:1000, oxygen 15L/min, systemic corticosteroid
- Discharge once stridor free at rest
