Asthma attack (acute asthma)


Asthma attack is a substantial worsening of asthma symptoms. The severity and duration of attacks are variable and unpredictable.

Assessment of the severity of asthma attack

The severity of the asthma attack must be rapidly evaluated by the following clinical criteria. Not all signs are necessarily present.

Assessment of severity in children under 2 years and adults

Mild to moderate attack

Severe attack

Life threatening attack

Able to talk in sentences

Respiratory rate (RR)
Children 2-5 years ≤ 40/minute
Children > 5 years ≤ 30/minute

Heart rate
Children 2-5 years ≤ 140/minute
Children > 5 years ≤ 125/minute

and

No criteria of severity

Cannot complete sentences in one breath
or
Too breathless to talk or feed

RR
Children 2-5 years > 40/minute
Children > 5 years > 30/minute
Adults ≥ 25/minute

Heart rate
Children 2-5 years > 140/minute
Children > 5 years > 125/minute
Adults ≥ 110/minute

SpO2 ≥ 92%

Altered level of consciousness (drowsiness, confusion, coma)

Exhaustion

Silent chest

Paradoxical thoracoabdominal movement

Cyanosis

Collapse

Bradycardia in children or arrhythmia/hypotension in adults

SpO2 < 92%

Treatment

Treatment and follow-up depend on the severity of the attack and the patient’s response:

Mild to moderate attack

– Reassure the patient; place him in a 1/2 sitting position.

– Administer:
• salbutamol (aerosol): 2 to 4 puffs every 20 to 30 minutes, up to 10 puffs if necessary during the first hour. In children, use a spacer1  to ease administration (use face mask in children under 3 years). Single puffs should be given one at a time, let the child breathe 4 to 5 times from the spacer before repeating the procedure.
• prednisolone PO: one dose of 1 to 2 mg/kg

– If the attack is completely resolved: observe the patient for 1 hour (4 hours if he lives far from the health centre) then give outpatient treatment: salbutamol for 24 to 48 hours (2 to 4 puffs every 4 to 6 hours depending on clinical evolution) and prednisolone PO (1 to 2 mg/kg once daily) to complete 3 days of treatment.

– If the attack is only partially resolved, continue with salbutamol 2 to 4 puffs every 3 to 4 hours if the attack is mild; 6 puffs every 1 to 2 hours if the attack is moderate, until symptoms subside, then when the attack is completely resolved, proceed as above.

– If symptoms worsen or do not improve, treat as severe attack.

Severe attack

– Hospitalise the patient; place him in a 1/2 sitting position.

– Administer:
• oxygen continuously, at least 5 litres/minute or maintain the SpO2 between 94 and 98%.
• salbutamol (aerosol): 2 to 4 puffs every 20 to 30 minutes, up to 10 puffs if necessary in children under 5 years, up to 20 puffs in children over 5 years and adults. Use a spacer to increase effectiveness, irrespective of age.
or salbutamol (solution for nebulisation), see Life-threatening attack.
• prednisolone PO: one dose of 1 to 2 mg/kg
In the case of vomiting, until the patient can tolerate oral prednisolone, use hydrocortisone IV:
Children 1 month to < 5 years: 4 mg/kg every 6 hours (max. 100 mg per dose)
Children 5 years and over and adults: 100 mg every 6 hours 

– If the attack is completely resolved, observe the patient for at least 4 hours. Continue the treatment with salbutamol for 24 to 48 hours (2 to 4 puffs every 4 hours) and prednisolone PO (1 to 2 mg/kg once daily) to complete 3 days of treatment.
Reassess after 10 days: consider long-term treatment if the asthma attacks have been occurring for several months. If the patient is already receiving long-term treatment, reassess the severity of the asthma (see table) and review compliance and correct use of medication and adjust treatment if necessary.

– If symptoms worsen or do not improve, see Life-threatening attack.

Life-threatening attack (intensive care)

– Insert an IV line.

– Administer:
• oxygen continuously, at least 5 litres/minute or maintain the SpO2 between 94 and 98%.
• salbutamol + ipratropium, solutions for nebulisation:

Children 1 month to < 5 years

salbutamol 2.5 mg + ipratropium 0.25 mg every 20 to 30 minutes

Children 5 to < 12 years

salbutamol 2.5 to 5 mg + ipratropium 0.25 mg every 20 to 30 minutes

Children 12 years and over and adults

salbutamol 5 mg + ipratropium 0.5 mg every 20 to 30 minutes

The two solutions can be mixed in the nebuliser reservoir. The solutions must be administered via an oxygen-driven nebuliser.
• corticosteriods (prednisolone PO or hydrocortisone IV) as for severe attack.

– If the attack is resolved after one hour: switch to salbutamol aerosol and continue prednisolone PO as for severe attack.

– If symptoms do not improve after one hour:
• administer a single dose of magnesium sulfate by IV infusion in 0.9% sodium chloride over 20 minutes, monitoring blood pressure:
Children over 2 years: 40 mg/kg
Adults: 1 to 2 g
• continue salbutamol by nebulisation and corticosteriods, as above.

Notes:
– In pregnant women, treatment is the same as for adults. In mild or moderate asthma attacks, administering oxygen reduces the risk of foetal hypoxia.
– For all patients, irrespective of the severity of the asthma attack, look for underlying lung infection and treat accordingly.



Footnotes
Ref Notes
1 If a conventional spacer is not available, use a 500 ml plastic bottle: insert the mouthpiece of the inhaler into a hole made in the bottom of the bottle (the seal should be as tight as possible). The child breathes from the mouth of the bottle in the same way as he would with a spacer. The use of a plastic cup instead of a spacer is not recommended (ineffective).