• Respiratory failure is present when lungs are unable to maintain normal gas exchange at rest,
• PaO₂ <8.0 kPa (type 1) and/or PaCO₂ >6.0 kPa (type 2)
• Identify the underlying cause

Symptoms and signs

• Drowsiness
• Warm peripheries, bounding pulse, tachycardia
• Central cyanosis (difficult to detect in anaemic patients)
• In patients with rising PaCO₂ flapping tremor and papilloedema

Investigations

• Arterial blood gases (ABG) while breathing air
• if clinical condition does not allow ABG when breathing air, record FiO₂
• Chest X-ray
• FBC
• U&E
• ECG

• Treat underlying cause
• Follow Treatment of hypoxaemia guideline
• Refer patients with neuromuscular disease or kyphoscoliosis presenting with type 2 respiratory failure to respiratory physician

• Advice on life-style appropriate to underlying disease that precipitated admission
• Refer all patients with type 1 or type 2 respiratory failure for follow up with respiratory physician