Synopsis
Recognise age-specific severe and life-threatening asthma from the worst feature, start oxygen and inhaled bronchodilator immediately, add anticholinergic and systemic corticosteroid, reassess repeatedly, and escalate safely to intravenous therapy and paediatric intensive care without sedation.
- Grade severity from the most dangerous feature. A child does not need every criterion, and falling tachycardia or respiratory rate with exhaustion is deterioration.
- First line: give oxygen to target 94–98% and salbutamol immediately. Mild-to-moderate attacks can use a pressurised metered-dose inhaler and spacer; severe or hypoxaemic attacks use an oxygen-driven nebuliser.
- Spacer regimen: give one salbutamol 100-microgram puff at a time with tidal breaths, repeating up to 10 puffs and reassessing; use a mask when a mouthpiece seal is unreliable.
- Severe nebuliser dose: salbutamol 2.5 mg under 5 years or 5 mg age 5 and over, repeated or continuously under senior monitoring according to response.
- Add nebulised ipratropium 250 micrograms to each of the first three salbutamol nebulisers in acute severe or life-threatening asthma.
- Give oral prednisolone early: commonly 20 mg age 2–5 and 30–40 mg age over 5 for at least 3 days, or follow BNF-C weight-based/local dosing. Use intravenous hydrocortisone if oral treatment cannot be taken.
- Reassess after every bronchodilator: mental state, speech or feeding, effort, air entry, saturation, heart and respiratory rates and peak flow if age and effort allow.
- Do not request chest radiography routinely. Image for suspected pneumothorax, focal collapse, foreign body or failure suggesting another diagnosis.
- Obtain blood gas in life-threatening or nonresponding disease. Do not stop bronchodilator to obtain it, and avoid arterial puncture if a venous or capillary sample answers the question.
- For poor response, senior-led intravenous magnesium sulfate 40 mg/kg, maximum 2 g, over 20 minutes is a common first intravenous bronchodilator option; monitor blood pressure.
- Intravenous salbutamol or aminophylline requires paediatric intensive-care-level expertise, dose verification and cardiac, potassium, lactate and glucose monitoring.
- Discharge requires sustained improvement on spaced inhaled treatment, normal activity and oxygenation, an ICS-containing preventer plan, observed technique, written action plan and review within 2 working days.
Key red flags
Silent chest, cyanosis, poor effort, exhaustion, confusion, drowsiness, hypotension or arrhythmia is life-threatening irrespective of respiratory rate.
Age over 5: saturation below 92%, peak flow 33–50%, respiratory rate above 30, heart rate above 125 or inability to complete sentences indicates acute severe asthma.
Age 2–5: saturation below 92%, inability to talk or feed, heart rate above 140, respiratory rate above 40 or marked accessory-muscle use indicates severe disease.
Normal carbon dioxide during a severe attack may be ominous; a raised PaCO2 indicates fatigue and respiratory failure.
Previous ventilation, intensive-care admission, recent oral steroid, high SABA use or absent ICS increases near-fatal risk and lowers escalation thresholds.
Asymmetry, sudden choking, stridor, urticaria, fever with focal signs or no bronchodilator response suggests foreign body, anaphylaxis, pneumonia or another diagnosis.
Investigation priorities
Grade response and identify hypoxaemia or fatigue while treatment proceeds.
Management branches
A child presents with a current asthma attack.
- Give oxygen for hypoxaemia and salbutamol by spacer or oxygen-driven nebuliser according to severity.
- Give systemic corticosteroid early and add ipratropium for severe or life-threatening disease.
- Reassess after every cycle and summon senior help at the first life-threatening feature.