Asthma (Acute)
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Assessment and Management
|
Severity |
Signs of Severity |
Management |
|
Mild |
Primary Normal mental state Subtle or no accessory muscle use/recession Secondary = O2 saturation > 95% in air Able to talk normally |
Salbutamol by MDI/spacer * - once and review after 20 mins. Ensure device / technique appropriate. Good response - discharge on B2-agonist as needed. Poor response - treat as moderate. Oral prednisolone (1 mg/kg daily for 1-3 days) if on prophylaxis or episode has persisted over several days. Provide written advice on what to do if symptoms worsen. Consider overall control and familyxs knowledge. Arrange follow-up as appropriate. |
|
Moderate |
Primary Normal mental state Some accessory muscle use/recession Secondary = O2 saturation 92-95% in air Tachycardia Some limitation of ability to talk |
Give O2 if O2 saturation is < 92%. Need for O2 should be reassessed. Salbutamol by MDI/spacer - 1 dose* every 20 minutes for 1 hour ; review 10-20 min after 3rd dose to decide on admission or discharge. Oral prednisolone (1 mg/kg daily for 3 days) The few children of moderate severity who can go home must be discussed with the registrar and should not leave Emergency until at least one hour after their last nebuliser. Arrange home treatment and follow-up as above. |
|
Severe |
Primary Agitated/distressed Moderate-marked accessory muscle use/recession Secondary = O2 saturation < 92% in air Tachycardia Marked limitation of ability to talk Note: wheeze is a poor predictor of severity. |
Oxygen. Salbutamol by MDI/spacer- 1 dose* every 20 minutes for 1 hour ; review on-going requirements 10-20 min after 3rd dose ? if improving reduce frequency, if no change continue 20 minutely, if deteriorating at any stage treat as critical. Ipratropium# by MDI/spacer Oral prednisolone (1 mg/kg daily); if vomiting give i.v. methylprednisolone. Involve senior staff. Arrange admission after initial assessment. |
|
Critical |
Primary Confused/drowsy Maximal accessory muscle use/recession Exhaustion Secondary = SaO2 < 90% in air Marked tachycardia Unable to talk |
Involve senior staff. Call ICU registrar to assess patient (5211) Oxygen. Continuous nebulised salbutamol (0.5% undiluted) - see below re toxicity Nebulised ipratropium 250 mcg 3 times in 1st hr only (20 minutely, added to salbutamol) Methylprednisolone 1 mg/kg i.v. 6-hourly. Aminophylline: If deteriorating or child is very sick
|
- = The arterial oxygen saturation (SaO2) may be reduced in the absence of significant airway obstruction by factors such as atelectasis and mucous plugging of airways. SaO2 is purely a measure of oxygenation, which may be preserved in the presence of deteriorating ventilation (with CO2 retention).
- * salbutamol 6 puffs if < 6 years old, 12 puffs if >6 years old
- # ipratropium (Atrovent 20mcg/puff) 4 puffs if < 6 years old, 8 puffs if >6 years old
History
Inquire specifically about the duration and nature of symptoms, treatments used (relievers, preventers), trigger factors (including upper respiratory tract infection, allergy, passive smoking), pattern and course of previous acute episodes (eg. admission or ICU admissions), parental understanding of the treatment of acute episodes, and the presence of interval symptoms (see Long Term Asthma Control below).
Consider other causes of wheeze (eg. bronchiolitis, mycoplasma, aspiration, foreign body)
Examination
The most important parameters in the assessment of the severity of acute childhood asthma are general appearance/mental state and work of breathing (accessory muscle use, recession), as indicated in the table. Initial SaO2 in air, heart rate and ability to talk are helpful but less reliable additional features. Wheeze intensity, pulsus paradoxus, and peak expiratory flow rate are not reliable.
Asymmetry on auscultation is often found due to mucous plugging, but warrants consideration of foreign body.
Investigations
Chest x-ray is not generally required (discuss with registrar/consultant if considering). Arterial blood gas and spirometry are rarely required in the assessment of acute asthma in children.
Notes
Long Term Asthma Control
- The frequency of acute episodes and any chronic symptoms should be reviewed.
- Specific questions should be asked about sleep disturbance (due to asthma), early morning symptoms, exercise induced cough or wheeze, and frequency of bronchodilator use.
Preventive Treatment
- Consider preventive treatment if there are frequent acute episodes or chronic symptoms (more than one disturbed night per week, difficulty participating in physical activities, or bronchodilator use on more than one day per week).
- First choice : inhaled corticosteroids.
- If commencing preventive treatment arrange early paediatric review.
- Careful attention must be paid to the delivery system chosen. Spacer devices should be used at all ages. A low volume spacer device with a well-sealing face mask should be used in younger children.
Discharge
- Each child should have a written action plan. This can be generated on the intranet Asthma action plan.
- Observe inhaler technique before discharge.
- Advise parents to seek further medical attention (preferably from their GP) should the patientxs condition deteriorate or if there is no significant improvement within 48 hours.
- At discharge all patients should have an outpatient appointment or appropriate follow-up arranged with a paediatrician and/or GP. Newly diagnosed patients should be referred to a paediatrician for review within 4-6 weeks.
- Parents should be informed of other sources of information about asthma such as the Asthma Foundation, and the Child Health Information Center (in RCH foyer)
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