Acute exacerbations of COPD

Investigations

• ABG: arterial, a raised pH may imply an alternative diagnosis.
• CXR to exclude pneumothorax and infection.
• CBC
• Urea & Creatinine
• Electrolyte
• CRP
• ECG
• Theophylline level if patient is taking regularly.
• Sputum culture if purulent.
• Blood cultures if pyrexial.

Treatment

• Assess severity (R.R, SaO₂, air entry, HR, Bl.pr, peripheral perfusion, conscious level)

• Exclude tension pneumothorax, PE, Pul.edema

• Optimize volume status

• Salbutamol 5mg/4h and ipratropium 500mcg/6h, Run nebulizer with air, not O₂

• Oxygen therapy if SaO₂ <88% or PaO₂ <7 kPa (≈ 52.5 mmHg):

  • Start at 24–28% O₂, aim sats 88–92%
  • Adjust according to ABG, aim Pa O₂ >8.0kPa (≈ 60 mmHg) with a rise in PaCO₂ <1.5kPa (≈ 11.25 mmHg)
  • Whenever you initiate or change oxygen therapy, do consider an ABG within 1h.

• IV hydrocortisone 200mg and oral prednisolone 30mg one daily (continue for 5-7d, longer "e.g ≥ 14days" or repeated courses needs tapering)

• if evidence of infection (if sputum is purulent, fever, ↑ CRP, or new change on CXR).

• Amoxicillin 500mg/8h orally or (Tetracycline 500mg/6h/7-10 days or Clarithromycin 500mg/12h/7-14 days orally)

• Chest Physiotherapy

• If no response:

  • IV aminophylline: load with 250mg over 20min, then infuse at a rate of ~500mcg/kg/h (300mcg/kg/h if elderly), where kg is ideal body weight
  • Do not give a loading dose to patients on maintenance methylxanthines (theophyllines/ aminophylline).
  • Check plasma levels daily.
  • ECG monitoring is required.

• If no response:

  • Non-invasive positive pressure ventilation (NIV)
  • Appropriate for conscious patients
  • If respiratory rate >30
  • Or pH <7.35
  • Or PaCO₂ rising despite best medical treatment (PaCO₂ >6.5 kPa "≈ 48.25 mmHg")
  • Patients who are not suitable for mechanical ventilation
    • Respiratory stimulant drug, eg doxapram 1.5–4mg/min IV
    • It is a short-term measure, used only if NIV is not available

• Intubation and ventilation

  • if pH <7.26
  • and PaCO₂ is rising despite non-invasive ventilation only where appropriate

• DVT prophylaxis

• Early rehabilitation and nutrition to prevent muscle wasting and deconditioning.