ABCs
- Check vitals + cardiac monitor If desaturation → 15 L NRB
- Target SpO₂:
- >94% (most patients)
- 88–92% if COPD / CO₂ retention
- If unsure → aim ~92% + send urgent VBG
Red flags
- Dyspnea at rest or rapidly worsening
- Chest pain (especially sudden/severe)
- Diaphoresis or syncope
- Hypoxia/cyanosis
- Hypotension or shock
- Stridor → airway compromise
- Unequal breath sounds → pneumothorax/collapse
- Silent chest → severe asthma
- Pulsus paradoxus / distant heart sounds → tamponade
- BP difference >20 mmHg → aortic dissection
- Reduced consciousness/agitation
HPI & examination
- Key History
- Onset and progression of dyspnea (acute vs gradual)
- Overload symptoms → orthopnea, PND, LL edema
- Chest pain, diaphoresis, nausea (cardiac)
- Fever, cough, sick contact (infectious)
- VTE risk → prior VTE, immobility, OCPs
- Lung disease → asthma, COPD, ILD
- Cardiac history → IHD, heart failure
- Renal/dialysis history
- Medications → diuretics, inhalers
- Examination
- General: distress, work of breathing
- Respiratory: air entry, wheeze, crackles, stridor
- Cardiac: heart sounds, murmurs
- Peripheral: edema, signs of DVT
- Neurological: mental status
Management
- Initial for ALL
- Oxygen → target saturation
- ABG/VBG + CXR ± BNP
- ECG + Troponin ± D-dimer (if chest pain)
- Escalation
- Persistent hypoxia → ICU
- Hemodynamic instability → urgent escalation
- Airway compromise → Anesthesia/ENT
| Condition | Key Clues | Management |
|---|---|---|
| Upper airway obstruction | Stridor, angioedema, anaphylaxis | Call for help immediately Airway support → Anesthesia/ENT |
| Pneumothorax | Sudden dyspnea, ↓ breath sounds | Urgent CXR Needle decompression if tension Surgical consult |
| Lung collapse | Unequal/absent breath sounds | Urgent CXR Respiratory consult |
| Pneumonia / HAP | Fever, cough | CXR + labs (CRP, PCT, RFT, LFT) Start empiric antibiotics (after senior input) |
| Pulmonary embolism | SOB, tachycardia, DVT risk | CTPA if stable If delayed → start anticoagulation Bedside echo if unstable |
| Asthma exacerbation | Wheeze, SOB | O₂ (15 L NRB) Salbutamol 2.5 mg neb q20 min+ Ipratropium 0.5 mg q20 min + IV Methylpred 40–60 mg Reassess after 1 hr |
| Severe asthma (red flags) | Silent chest, drowsy, ↑CO₂ | Call for help + ICU review |
| Pulmonary edema (overload) | Orthopnea, PND, edema, ↑BNP | IV furosemide if BP stableO₂ ± NIV |
| Aortic dissection (stable) | Tearing pain, BP difference | CTA Control SBP 100–120, HR ≤60 Start β-blocker |
| Aortic dissection (unstable) | Shock, severe pain | Call for help immediately TEE/POCUS Cardiothoracic consult Hemodynamic support |
Notes (High Yield)
- PO furosemide ≈ ½ IV dose
- Lasix naïve → start 20–40 mg IV
- On Lasix → give 1–2.5× daily oral dose (IV)
- If no response → double dose
- Max single dose: 80–200 mg
- Max daily: 600 mg
- Higher doses may be needed in renal disease
See also: MOC+ Volume 2: Cardiopulmonary — covers acute heart failure, PE, and asthma/COPD exacerbations in depth.
Last reviewed · May 2026