Table 2. Severity classification of asthma exacerbations.

Clinical features	Mild	Moderate	Severe	Respiratory arrest imminent
Breathless	When walking or going up a flight of stairs	On minimal exertion	At rest	–
Body position	Can lie down	Prefers sitting	Hunched forward	–
Speech	Speaks in sentences	Speaks in phrases	Speaks in words	Unable to speak
Alertness	May be agitated	Sometimes agitated	Usually agitated	Drowsy or confused
Sweating	None	Yes	Sweats profusely	–
Respiratory rate	Slightly increased	Increased	Often >30/min	–
Laboring of accessory muscles and suprasternal retractions	Usually not	Usually	Frequent	Paradoxical thoracoabdominal movements
Wheeze	Moderate; usually only end-expiratory	Loud; throughout exhalation	Loud; throughout inhalation and exhalation	Weakened or absent

Note: a classification of severity can be indicated when several but not necessarily all of the clinical features are met.