| Moderate | * Increasing asthma symptoms * PEFR >50-70% of best or predicted |
|---|---|
| Severe | * PEFR 33-50% of best or predicted * RR (\geq) 25 breaths/min * HR (\geq) 110 * Inability to complete sentences in one breath |
| Life-threatening | * PEFR <33% of best or predicted * SpO2 <92% * Silent chest, cyanosis, poor respiratory effort, bradycardia, hypotension, confusion, exhaustion, coma |
| Near-fatal | * Raised PaCO2 and/or requiring mechanical ventilation with raised inflation pressures |