What is the emergency management approach for a patient with a COPD (Chronic Obstructive Pulmonary Disease) exacerbation?

Emergency Management of COPD Exacerbation

Immediately initiate controlled oxygen therapy targeting SpO2 88-92% using a 24-28% Venturi mask or nasal cannulae at 1-2 L/min, combined with nebulized short-acting bronchodilators (salbutamol 2.5-5 mg plus ipratropium 0.25-0.5 mg), and oral prednisone 30-40 mg, while obtaining arterial blood gases within 60 minutes to assess for hypercapnic respiratory failure. 1, 2, 3

Immediate Assessment and Oxygen Therapy

Triage as very urgent if respiratory rate >30 breaths/min or significant likelihood of hypercapnic respiratory failure. 1

Oxygen Delivery Protocol

• Start with 24% Venturi mask at 2-3 L/min OR nasal cannulae at 1-2 L/min OR 28% Venturi mask at 4 L/min 1
• Target SpO2: 88-92% (not higher - hyperoxemia increases mortality 9-fold compared to normoxemia) 1, 2, 4
• Obtain arterial blood gases within 30-60 minutes of starting oxygen and repeat if clinical deterioration occurs 5, 1, 2
• Critical pitfall: High-flow oxygen (>28% FiO2) before knowing blood gas results causes hypercapnic respiratory failure and respiratory acidosis 5, 6, 4
• If PaO2 responds and pH remains >7.26, increase oxygen concentration until PaO2 >7.5 kPa (56 mm Hg); if pH falls below 7.26, consider NIV 5

Bronchodilator Therapy

Administer immediately upon arrival:

• Salbutamol 2.5-5 mg PLUS ipratropium bromide 0.25-0.5 mg via nebulizer 1, 3, 7
• Combination therapy provides superior bronchodilation lasting 4-6 hours compared to either agent alone 3, 7
• Repeat every 4-6 hours during acute phase (first 24-48 hours) 3
• Drive nebulizers with compressed air (not oxygen) if PaCO2 elevated or respiratory acidosis present; give supplemental oxygen via nasal prongs at 1-2 L/min during nebulization 5
• Do NOT use intravenous theophylline/aminophylline - increases side effects without added benefit 5, 3

Systemic Corticosteroids

Prednisone 30-40 mg orally once daily for exactly 5 days - start immediately 1, 2, 3

• Oral route equally effective as IV unless patient cannot tolerate oral intake 3
• Improves lung function, oxygenation, shortens recovery time, and reduces treatment failure by >50% 2, 3
• Do NOT continue beyond 5-7 days for single exacerbation - no additional benefit and increases harm 3

Antibiotic Therapy

Prescribe antibiotics for 5-7 days if patient has:

• All three cardinal symptoms (increased dyspnea, increased sputum volume, increased sputum purulence) OR
• Two cardinal symptoms with one being increased sputum purulence OR
• Requires mechanical ventilation 1, 2, 3

First-line choices:

• Amoxicillin OR
• Amoxicillin/clavulanate OR
• Doxycycline OR
• Azithromycin 1, 3
• Duration: 5-7 days 1, 2, 3
• Antibiotic therapy reduces short-term mortality by 77% and treatment failure by 53% 2

Noninvasive Ventilation (NIV)

Initiate NIV immediately if:

• Respiratory acidosis (pH <7.35) persists >30 minutes after standard medical management OR
• PaCO2 rising despite controlled oxygen OR
• Severe dyspnea with respiratory muscle fatigue OR
• Persistent hypoxemia despite oxygen 1, 2, 3

NIV benefits:

• Reduces intubation rates by ~50% 3
• Decreases mortality 2
• Shortens hospitalization 2, 3
• Improves gas exchange and reduces work of breathing 2, 3
• Success rate 80-85% when used appropriately 2

Relative contraindications to NIV:

• Confusion/altered mental status 3
• Large volume secretions 3
• Hemodynamic instability 2

Additional Urgent Investigations

Within first hour:

• Arterial blood gases (mandatory - note FiO2) 5, 1
• Chest radiograph (changes management in 7-21% by identifying pneumonia, pneumothorax, pulmonary edema) 3

Within 24 hours:

• Full blood count 5
• Urea and electrolytes 5
• ECG (if heart rate <60 or >110/min, or cardiac symptoms present) 5, 3
• Sputum culture if frankly purulent 5
• Blood cultures if pneumonia suspected 5

Critical Monitoring Parameters

• Recheck arterial blood gases 30-60 minutes after any change in oxygen concentration 5, 1
• pH <7.26 predicts poor outcome - consider ICU admission 5
• Monitor for signs of respiratory failure: worsening dyspnea despite treatment, confusion, inability to maintain adequate oxygenation 2
• Serial peak flow measurements starting as soon as possible 5

Common Pitfalls to Avoid

• Never give high-flow oxygen (>28% FiO2) before knowing blood gas results - causes hypercapnic respiratory failure 5, 6, 4
• Do not use chest physiotherapy - no evidence of benefit in acute COPD exacerbations 3
• Avoid sedatives and hypnotics - worsen respiratory depression 1
• Do not delay NIV in patients with acute hypercapnic respiratory failure 3
• Do not use theophylline - side effects without added benefit 5, 3

Supportive Measures

• Prophylactic subcutaneous heparin for VTE prevention in acute-on-chronic respiratory failure 3
• Diuretics only if peripheral edema AND raised jugular venous pressure present 3
• Continue maintenance COPD medications (do not stop triple therapy during exacerbation) 3

Disposition Criteria

Admit to hospital if:

• Marked increase in symptom intensity requiring nebulization 3
• Severe underlying COPD 3
• New physical signs (cyanosis, peripheral edema, confusion) 5, 3
• Failure to respond to initial treatment 3
• Significant comorbidities 3
• Frequent exacerbations 3
• Inability to care for self at home 3
• Age >75 years with multiple risk factors 3

ICU admission if:

• pH <7.26 despite initial therapy 5
• Severe life-threatening episode 1
• NIV failure or contraindications to NIV with worsening respiratory failure 2