Asthma - life threatening
This document is only valid for the day on which it is accessed. Please read our disclaimer.
Recognition of Life-threatening Asthma
- Deterioration despite maximal therapy on severe asthma pathway
- Respiratory - cyanosis/exhaustion
- Neurological - confusion/drowsiness.
- Cardiovascular - pulsus paradoxus
- Consider diagnoses other than asthma, especially in infants with poorly responsive respiratory distress. No infant (< 1 year) should be started on intravenous bronchodilators without discussion with a consultant.
If the patient's condition is improving therapy can be de-escalated at any stage - see Asthma - Management of Acute Guideline.
- Call for assistance - request urgent review with PICU/CED Senior
- OXYGEN - use high flow oxygen via mask (e.g. 15L/min).
- IV access
- Give Hydrocortisone 4 mg/kg IV as soon as possible.
- Nebulised bronchodilators - Continuous nebulised salbutamol 5 mg/dose for all ages. Add ipratropium bromide 0.25 mg to the second nebuliser, if there is inadequate response to the first salbutamol nebule. Repeat ipratropium every 20 minutes for 3 doses, then every 4 hours.
- IV salbutamol bolus Give 10 micrograms/kg (single dose maximum 500 micrograms). Over 2 minutes. Give in a minimum volume of 5ml (can be diluted with 0.9% Saline). Repeat dose at 10 minutes if still not improving
- IV magnesium sulphate bolus. Use magnesium sulphate 49.3% (493mg/ml). Give 0.2 mmol/kg over 20 minutes (dilute to 50mls with sodium chloride 0.9% and infuse via syringe driver). Maximum dose 2.5 g.
- IV aminophylline bolus. Give 10 mg/kg IV (maximum dose 500 mg) over 1 hour (dilute required dose to 50mL. Compatible with Sodium chloride 0.9%, Glucose 5% or Glucose 10%). If the child is already on oral theophylline, do not give IV aminophylline unless you have obtained a baseline serum level and can calculate a reduced loading dose. If patient is on any other medications you must check for potential interactions and adjust dose accordingly (see below).
- If inadequate response to bolus therapy then start further IV therapy in form of salbutamol +/- aminophylline infusion(s). These children require admission to PICU.
Remember if child is improving therapy can be de- escalated at any stage
5 -10 microgram/kg/min for 1 hour then reduce to 1 - 2 microgram/kg/min
If Patient Weight < 16kg
Add 3 mg/kg of IV salbutamol solution (1 mg/ml) to a 50 ml syringe and make up to 50 ml with 5% glucose
Then 1 ml/hr = 1 microgram/kg/min
If Patient Weight > 16kg
Draw up neat IV salbutamol solution (1 mg/ml) into a 50ml syringe (i.e. not diluted)
Then rate (ml/hr) = 0.06 x weight (kg) x dose (microgram/kg/min)
For example if you have a 20 kg child and want to infuse salbutamol at 5 microgram/kg/min then set rate at 0.06 x 20 x 5 = 6 ml/hr
|IV Salbutamol infusion chart for patients >16kg|
|Wt(kg)||1 microgram/kg/min||2 microgram/kg/min||5 microgram/kg/min||10 microgram/kg/min|
|Dose if patient aged 1 - 9 years
Add 55 mg/kg of IV aminophylline solution (25 mg/ml) to a 50 ml syringe and make up to 50 ml with 5% glucose
Then infuse at 1 ml/hr
If weight between 23-30kg (50th centile for 9 year olds) then use neat IV aminophylline solution (25mg/ml) in a 50ml syringe and run at 1ml/hr.
|Dose if patient aged 10 - 15 years and weight < 35
Add 35 mg/kg of IV aminophylline solution (25 mg/ml) to a 50 ml syringe and make up to 50 ml with 5% glucose
Then infuse at 1 ml/hr
|Dose if patient aged 10 - 15 years and weight > 35
Draw up neat IV Aminophylline solution (25 mg/ml) into a 50 ml syringe
Then infuse at 0.028 ml/kg/hr
For example if you have a 40 kg child then infusion rate will be 40 x 0.028 = 1.12 ml/hr
|Dose adjustment for obesity
Use 50th percentile of expected weight for age
|Factors increasing Aminophylline clearance
|Factors decreasing Aminophylline clearance
Hepatic or renal dysfunction
British Guideline on the Management of Asthma (http://www.sign.ac.uk/guidelines/published/support/guideline63/download.html)
Advanced Paediatric Life Support, BMJ Book - Third Edition
Browne GJ, Trieu L, Van Asperen P. Randomized, double blind, placebo-controlled trial of intravenous salbutamol and nebulized ipratropium bromide in early management of severe acute asthma in children presenting to an emergency department. Crit Care Med 2002 Feb; 30(2): 448-53
Cheuk DKL, Chau TCH, Lee SL. A meta-analysis on intravenous magnesium sulphate for treating acute asthma. Arch Dis Child 2005; 90: 74-77
Did you find this information helpful?
- Date last published: 01 April 2007
- Document type: Clinical Guideline
- Services responsible: Children’s Emergency Department
- Author(s): Fran Settle
- Editor: Greg Williams
- Review frequency: 2 years
SIGN UP TO RECEIVE GUIDELINE UPDATES
Subscribe below if you want us to let you know about new or updated guidelines
More From Starship
We welcome your involvement. Find out what guidelines are currently in development or under review. Find out more...
Read about the governance process around the Starship Clinical Guidelines and how to format guidelines in development.