Asthma Severity

Question 1

What are the criteria for moderate acute asthma?

Answer 1

Increasing symptoms
Peak flow > 50-75% best or predicted
No features of acute severe asthma

Question 2

What are the criteria for severe acute asthma?

Answer 2

Any ONE of:
Peak flow 33-50% best or predicted
Respiratory rate ≥ 25/min
Heart rate ≥ 110/min
Inability to complete sentences in one breath

Question 3

What are the criteria for life-threatening acute asthma?

Answer 3

Any one of the following in a patient with severe asthma:

Peak flow < 33% best or predicted
Arterial oxygen saturation (SpO2) < 92%
Partial arterial pressure of oxygen (PaO2) < 8 kPa
Normal partial arterial pressure of carbon dioxide (PaCO2) (4.6–6.0 kPa)
Silent chest
Cyanosis
Poor respiratory effort
Arrhythmia
Exhaustion
Altered conscious level
Hypotension

Question 4

What are the criteria for near-fatal acute asthma?

Answer 4

Raised PaCO2 and/or the need for mechanical ventilation with raised inflation pressures