How to manage a patient with a history of Chronic Obstructive Pulmonary Disease (COPD) presenting to the Emergency Room (ER) with breathlessness?

Management of COPD Exacerbation with Breathlessness in the Emergency Room

For patients presenting to the emergency room with breathlessness due to COPD exacerbation, oxygen therapy should be titrated to maintain oxygen saturation between 88-92% to reduce mortality risk. 1

Initial Assessment

• Assess airway, breathing, and circulation (ABC) first, followed by a focused history including exercise tolerance, current treatments (especially nebulizers and long-term oxygen therapy), time course of exacerbation, and previous admissions 1
• Document signs of infection (pyrexia, purulent sputum), severe airway obstruction (audible wheeze, tachypnoea, accessory muscle use), peripheral edema, cyanosis, and/or confusion 1
• Measure pulse and respiratory rate in all cases 1
• Always use pulse oximetry to measure oxygen saturation in patients with breathlessness 1
• Obtain arterial blood gas measurement on arrival, noting the inspired oxygen concentration 1
• Order chest radiograph as an urgent investigation 1

Oxygen Therapy Management

For Known COPD Patients:

• Use a 24% Venturi mask at 2-3 L/min or 28% Venturi mask at 4 L/min (if 24% mask unavailable) 1
• Alternatively, use nasal cannulae at 1-2 L/min if Venturi masks are unavailable 1
• Target oxygen saturation of 88-92% 1
• Check arterial blood gases within 60 minutes of starting oxygen therapy and within 60 minutes of any change in inspired oxygen concentration 1
• If oxygen saturation remains below 88% despite a 28% Venturi mask, change to nasal cannulae at 2-6 L/min or a simple face mask at 5 L/min, maintaining the target saturation of 88-92% 1

For Suspected COPD (patients >50 years, long-term smokers with chronic breathlessness):

• Treat as having suspected COPD with the same oxygen targets (88-92%) pending blood gas results 1
• Patients with respiratory rate >30 breaths/min should have flow rates set above the minimum specified for the Venturi mask to compensate for increased inspiratory flow 1

Caution:

• Avoid excessive oxygen use as it increases the risk of respiratory acidosis if PaO₂ is above 10.0 kPa 1
• Research shows that even modest elevations in oxygen saturations (93-96%) are associated with increased mortality risk compared to the 88-92% target range 2
• If respiratory acidosis develops due to excessive oxygen therapy, do not discontinue oxygen immediately but step down to 28% or 35% oxygen via Venturi mask or 1-2 L/min via nasal cannulae 1

Bronchodilator Therapy

• Administer nebulized bronchodilators on arrival and at 4-6 hourly intervals thereafter 1
• For patients with COPD and elevated PaCO₂, nebulizers should be driven by compressed air rather than oxygen 1
• Ipratropium bromide (anticholinergic) can be used, which produces significant improvements in pulmonary function within 15-30 minutes, reaching peak effect in 1-2 hours and persisting for 4-5 hours 3
• Consider combination therapy with beta-adrenergic bronchodilators (like albuterol) which can produce additional improvement in FEV₁ and FVC 3

Additional Management

• Consider antibiotics if two or more of the following are present: increased breathlessness, increased sputum volume, or development of purulent sputum 1
• For purulent sputum, send samples for culture 1
• Consider oral corticosteroids (usually 30 mg per day for one week) 1
• Monitor oxygen saturation continuously until the patient is stable 1
• Patients with respiratory rate >30 breaths/min should be triaged as very urgent 1
• For patients with severe acidosis (pH<7.25), consider alternative ventilation strategies 1

Weaning and Discontinuation of Oxygen

• Lower oxygen concentration if the patient is clinically stable and oxygen saturation is above the target range 1
• Most stable convalescent patients will eventually be stepped down to 2 L/min via nasal cannulae prior to cessation of oxygen therapy 1
• Patients at risk of hypercapnic respiratory failure may be stepped down to 1 L/min (or occasionally 0.5 L/min) via nasal cannulae or a 24% Venturi mask at 2 L/min before stopping oxygen 1
• Stop oxygen therapy once the patient is clinically stable on low-concentration oxygen and oxygen saturation is within the desired range on two consecutive observations 1

Common Pitfalls to Avoid

• Administering high-flow oxygen (>28%) to COPD patients before blood gas results are available, which can worsen hypercapnic respiratory failure 1
• Setting different target saturations based on carbon dioxide levels is not justified by evidence; all COPD patients should have the same target range of 88-92% 2
• Failing to recognize COPD in older smokers with chronic breathlessness 1
• Discontinuing oxygen therapy abruptly when respiratory acidosis is detected 1
• Inadequate monitoring of oxygen saturation after initiating therapy 1