Acute Exacerbation of COPD

Clinical Description

Acute worsening of dyspnoea, increased sputum volume, purulent sputum (+ / -fever) that requires additional treatment

• Exacerbations progression and result in loss of lung function and poor quality of life
• can be mild, moderate, or severe

Causes of exacerbations

• tracheobronchial infections main trigger - viral (rhinovirus) > bacterial (S.

pneumoniae, H. influenzae, Moraxella catarrhalis. Consider Pseudomonas aeruginosa if frequent exacerbator and recent hospital admission)

• environmental exposure / air pollution (respirable particles, ozone)
• allergens
• aspiration and GORD
• weather changes
• discontinuation of maintenance treatment

Differential diagnosis of exacerbations

• non-pulmonary infections
• pulmonary embolism
• pneumothorax
• pleural effusion
• CCF with pulmonary oedema

Investigations

• FBC, blood culture, sputum analysis, CXR

Treatment

• Exacerbations need bronchodilators, antibiotics, and steroids
• Nebulized salbutamol 5mg / ipratroprium bromide and oral aminophylline 100 mg 8 hourly PO. Can use salbutamol inhaler with spacer if no nebulised salbutamol
• Prednisolone 40 mg daily PO for 5 days (5 days course is enough).

Steroids shorten hospital stay / recovery time and improve lung function oxygenation and clinical outcome.

• Antibiotics (if bacterial infection trigger suspected)
• Amoxicillin 1g 8 hourly PO for 7 days. Alternative Amoxicillin + Clavulanic acid (AugmentinR) 625mg 8 hourly PO or doxycycline 100mg 12 hourly or azithromycin 500mg daily.

ceftriaxone 2g daily IV (if severe exacerbation) o if frequent exacerbation with recent hospital admission and antibiotic use: cover for Pseudomonas spp e.g., with ciprofloxacin 500mg 12 hourly for 7 days

• oxygen saturation and the use of oxygen
• COPD patients often have lower SpO2 than asthma patients, even when stable.

o in asthma, if SpO2 drops below 95%, it is worrisome.

o a COPD patient may be stable with SpO2 as low as 87%.

• avoid the use of high flow oxygen in COPD patients wherever possible (as oxygen may remove their hypoxia dependent respiratory drive and cause hypoventilation→ CO2 retention, narcosis → coma).
• use 2 L / min oxygen as treatment or less, or to target SpO2 to 88 - 92 %.

NIV (non-invasive ventilation) for severe exacerbation: CPAP is preferred if no contraindications

• Improves oxygenation / gas exchange / survival
• Reduce work of breathing and need for intubation
• Reduce hospital stay
• Improves respiratory acidosis

Before discharge

• start inhaled bronchodilators asap when stable before hospital discharge
• if frequent exacerbator: regular salbutal 2 puffs 6hrly through spacer
• long term use of oral steroid is not required
• plan for follow-up within 1 month: 20% of patients may not recover at 8 weeks