Management of severe asthma in children.

Management of Paediatric Acute Asthma (Asthma Exacerbation):
Introduction: asthma is a chronic disease of childhood which is intermittent, reversible obstructive airway disease, characterized by 3Rs: Recurrent, Reversible and Responsive. Clinically it manifests as recurrent episodes of wheezing, dyspnoea, chest tightness, and cough.
History:
Is it first attack or already diagnosed? ask about treatment if any; triggering factors; family history of asthma, atopy, or allergic disease; Consider other causes of wheeze e.g. bronchiolitis, aspiration, foreign body, anaphylaxis.
Examination:
*Degree of respiratory distress
- Respiratory rate – compare to age-appropriate normal ranges
- Use of accessory muscles and recession
- Posture or position
*Oxygen saturation by pulse oximetry
* Ability to talk in phrases, sentences or words
*Any clinical signs of major atelectasis or pneumothorax (decreased air entry or silent chest)
*Mental state (alertness and responsiveness)
*Heart rate
Investigations:
Generally no investigations are required in assessing acute asthma.
• Chest x-ray – consider in patients presenting with first episode of wheeze, particularly if doubt about
diagnosis. Children with known asthma do not require a CXR unless there is a suspicion of pneumothorax
or major collapse/consolidation.
• Blood tests (including blood gases) – not routinely required.
Per clinical examination, asthma severity will be divided into mild, moderate, severe and critical (life threatening). See below table for more illustration:
Here in this topic, we are going to discuss how to deal and handle a child with severe and critical (life threatening) asthma only.
Management: it’s better to admit the patient to PICU:
- Oxygen to keep saturation ≥ 93% (10-15L/min especially in critical asthma)
- Inhaled SABA: Albuterol (also known as salbutamol -ventolin-) by nebuliser – 3 doses 20 minutely
<6 years – 2.5mg nebulised over 10-15 minutes
≥6 years – 5mg nebulised over 10-15 minutes
Review ongoing requirements every 10-20 minutes after 3rd dose. If improving, reduce frequency, if no change, continue 20 minutely. - IV Albuterol: In deteriorating or in case of critical asthma use IV Albuterol instead of nebulised. Bolus:5microgram/kg/min for first hour then consider infusion.
Infusion:1-2 microgram/kg/min - Ipratropium bromide: (250microgram) via nebuliser 3 times in 1st hour (20 minutely, added to Salbutamol)
Wean at same rate as Salbutamol and cease once on 1-2hrly - Oral prednisolone. Give 2mg/kg/day (maximum dose 60mg) for initial dose and 1mg/kg
for subsequent doses. Use multiples of 5mg for ease of administration.
If vomiting or cannot take oral medications give>> - IV hydrocortisone 10-20mg/kg 6 hourly (maximum 2oomg)
- Aminophylline infusion: Loading dose of 5mg/kg (maximum 500mg) over at least 60 minutes inside normal saline followed by an infusion of:
<12 years – 1 mg/kg/hour
12 years to adult – 0.5 to 0.7 mg/kg/hour. - Magnesium sulphate: 25-50mg/kg over 20-30 minutes.
- Adrenaline amp: 0.01mg/kg IM or SC if poor air entry all over the chest or silent chest.
- Intubation and mechanical ventilation: for extreme cases with impending respiratory failure.
- sustained improvement of symptoms
- normal physical finding
- oxygen saturation more than 92% for more than 4 hours on room air
- PEFR > 70%