Hypoxia - Reacting to Low Oxygen Saturations
Related Subjects: Asthma
|Acute Severe Asthma
|Exacerbation of COPD
|Pulmonary Embolism
|Cardiogenic Pulmonary Oedema
|Pneumothorax
|Tension Pneumothorax
|Respiratory (Chest) infections Pneumonia
|Fat embolism
|Hyperventilation Syndrome
|ARDS
|Respiratory Failure
🫁 Emergency Assessment of Acute Breathlessness
| 🩺 Immediate A–E Assessment |
|---|
- 🅰️ Airway: Check airway is patent; suction/clear if needed.
- 🫁 Breathing: If no respiratory effort → 🚨 CALL ARREST TEAM.
- ❤️ Circulation: If no palpable pulse → 🚨 CALL ARREST TEAM.
- 🧠 Disability: If GCS < 9 → 🚨 CALL ANAESTHETIST.
|
⚡ Key Actions
- 🎯 Target O₂: If COPD, set SpO₂ target 88–92%.
- 🪑 Position: Sit patient upright → improves diaphragmatic movement & work of breathing.
- 🫁 Airway: Head tilt + chin lift if needed.
- 💨 Oxygen:
- Up to 15 L/min non-rebreathe mask (unless COPD → Venturi 24–28%).
- 🧠 Breathing status:
- If comatose → check glucose (give 100 ml 10% dextrose) or give naloxone (400 mcg IV/IM).
- If hypoventilating → call anaesthetics, consider BVM ventilation.
- 💉 Circulation:
- Assess for shock, obtain IV access.
- Start IV 0.9% saline unless fluid overloaded.
- 📞 Call senior help: Involve medical registrar early if no rapid improvement.
🔍 Focused Examination Findings & Actions
- 😮💨 Bronchospasm (Asthma/COPD): Nebulised salbutamol ± ipratropium.
- 💊 Hypoventilation: Sedation, seizure, obesity, OSA → give O₂, consider naloxone.
- 💦 Signs of fluid overload: JVP↑, basal creps, tachycardia → IV furosemide.
- 🫀 Clear chest, sudden SOB: Think PE → urgent CTPA.
- 🤒 Cough, sputum, fever: Pneumonia or COVID-19.
- ⚡ Anaphylaxis: IM adrenaline + salbutamol.
- 🫧 Atelectasis/mucus plugging: Encourage cough, chest physio.
🧪 Key Investigations
- 🩸 ABG: Assess O₂, CO₂, pH, HCO₃⁻, base excess → classify T1 vs T2 respiratory failure.
- 🩻 Portable CXR → infection, collapse, oedema, pneumothorax.
- ❤️ 12-lead ECG → rule out arrhythmia, RV strain, ACS/PE changes.
🧾 Differential Diagnosis
- 🫧 Pneumothorax
- 😮💨 Asthma
- 💦 Pulmonary oedema
- 🫀 Pulmonary embolism
- 🌬️ COPD exacerbation
- 💊 Hypoventilation → sedation, opiates, obesity, OSA
- 🤒 Chest infection (COVID-19, pneumonia)
- 🟤 Mucus plugging
- ⬇️ Lung collapse
