Appendix

Acute Dyspnea

Adult with new or worsening shortness of breath.

Stepwise approach

    SpO2 < 90%, RR > 30, or signs of exhaustion?

    CURB-65

    0
    Low (< 3% mortality) — outpatient

    Bedside differential

    • Pneumonia
      Fever, productive cough, focal crackles
    • Pulmonary embolism
      Sudden onset, clear chest, tachycardia
    • Acute heart failure
      Orthopnea, edema, raised JVP, bibasal crackles
    • COPD / asthma exacerbation
      Wheeze, known airway disease
    • DKA (compensatory)
      Kussmaul breathing, high glucose

    Confirmatory criteria

    • Pneumonia: New infiltrate on CXR + compatible clinical syndrome
    • Heart failure: BNP > 100 pg/mL / NT-proBNP > 300 + congestion on imaging