Variable | Severe exacerbation | Imminent respiratory arrest |
---|---|---|
Symptoms | Â | Â |
   Dyspnea | At rest |  |
   Speech | Single words, not sentences of phrases |  |
   Alertness | Agitated | Drowsy or confused |
Signs | Â | Â |
   Respiratory rate | >30 breaths/min |  |
   Heart rate | >120 beats/min | Bradycardia |
   Pulsus paradoxus | >25 mmHg | Absence (muscle fatigue) |
   Use of accessory muscles | Evident | Abdominal paradox |
   Wheeze | Present – loud | 'Silent chest' |
Functional assessment | Â | Â |
   PEF | <50% of predicted |  |
   PaO2 | <60 mmHg |  |
   PaCO2 | >42 mmHg |  |
   SaO2 | <90% |  |