What are the management strategies for Chronic Obstructive Pulmonary Disease (COPD) based on Harrison's Principles of Internal Medicine?

Management of Chronic Obstructive Pulmonary Disease (COPD)

Smoking cessation is the single most critical intervention at all stages of COPD and must be prioritized above all other therapies, as it is one of only two interventions proven to modify survival (along with long-term oxygen therapy in hypoxemic patients). 1

Initial Assessment and Diagnosis

Spirometry is essential for diagnosis and severity assessment:

• Post-bronchodilator FEV1/FVC < 0.7 confirms persistent airflow limitation 2
• A positive bronchodilator response (FEV1 increase ≥200 ml AND ≥15% from baseline) suggests possible asthma rather than pure COPD 3, 2
• Chest radiography excludes other pathologies but cannot positively diagnose COPD 3, 2
• Arterial blood gas measurement is necessary in severe COPD to identify hypoxemia (PaO2 <7.3 kPa or 55 mmHg) with or without hypercapnia 3, 2, 1

Pharmacological Management by Disease Severity

Mild COPD

For patients with mild disease and intermittent symptoms, use short-acting bronchodilators as needed:

• Short-acting β2-agonist OR inhaled anticholinergic as needed based on symptomatic response 3, 2, 1
• This is the only required pharmacotherapy for asymptomatic patients with mild disease 4

Moderate COPD

For patients with moderate disease and persistent symptoms despite as-needed bronchodilators:

• Regular therapy with short-acting β2-agonist and/or anticholinergic, or combination of both 3, 2, 1
• A corticosteroid trial (30 mg prednisolone daily for 2 weeks) should be considered in all moderate disease patients, with objective spirometric assessment required 3, 2, 1
• Objective improvement occurs in only 10-20% of cases and is defined as FEV1 increase ≥200 ml AND ≥15% from baseline 3, 2, 1
• Subjective improvement alone is not a satisfactory endpoint—objective spirometric improvement must be documented 3, 2

Severe COPD

For patients with severe disease, combination therapy is mandatory:

• Regular combination therapy with β2-agonist AND anticholinergic agents 3, 2
• Long-acting bronchodilators (LAMA/LABA combination) should be used as maintenance treatment to maximize bronchodilation 5, 6
• Consider adding inhaled corticosteroids to LABA/LAMA in patients with repeated exacerbations (≥2 per year) and FEV1 <50% predicted, particularly those with asthma-COPD overlap or elevated blood eosinophils 5

Important caveats regarding inhaled corticosteroids:

• ICS/LABA combination reduced mortality compared to placebo (relative risk 0.82) and ICS alone (relative risk 0.79), with absolute reductions of 1% or less 3
• Increased risk of pneumonia exists in COPD patients treated with ICS—monitor for signs and symptoms 7
• Do not use LABA monotherapy; always combine with anticholinergics or ICS to avoid overdose risk 7

Optimizing Inhaler Therapy

• Optimize inhaler technique and select appropriate device to ensure efficient delivery 3, 2
• Theophyllines have limited value in routine COPD management due to side effects and narrow therapeutic index 3, 2, 8
• Long-acting β2-agonists should only be used if objective evidence of improvement is available 3, 2

Non-Pharmacological Management

Smoking Cessation (Mandatory at All Stages)

Active participation in structured smoking cessation programs with nicotine replacement therapy achieves the highest sustained quit rates:

• Smoking cessation prevents accelerated lung function decline but cannot restore already lost function 3, 2, 1
• This intervention must be addressed at every clinical encounter 1

Pulmonary Rehabilitation

Pulmonary rehabilitation should be implemented in moderate to severe disease:

• Improves exercise performance and reduces breathlessness 3, 2, 1
• Reduces exacerbation rate, urgent visits, and hospitalization duration 9
• Should be offered to all patients with dyspnea, exercise intolerance, or activity limitations despite optimal pharmacotherapy 9

Additional Non-Pharmacological Interventions

• Annual influenza vaccination, especially for moderate to severe disease 3, 2, 1
• Exercise should be encouraged at all disease stages 3, 2, 1
• Both obesity and poor nutrition require active treatment 3, 2, 1
• Assess for depression and provide appropriate treatment 3, 2

Management of Advanced Disease

Long-Term Oxygen Therapy (LTOT)

LTOT is one of only two interventions proven to prolong life in COPD (along with smoking cessation):

• Prescribe LTOT when PaO2 ≤7.3 kPa (55 mmHg) or SaO2 ≤88% confirmed twice over 3 weeks 3
• Also indicated if PaO2 between 7.3-8.0 kPa (55-60 mmHg) with evidence of pulmonary hypertension, peripheral edema, or polycythemia (hematocrit >55%) 3
• LTOT reduced mortality with relative risk 0.61 in symptomatic patients with resting hypoxia 3
• Short-burst oxygen for breathlessness lacks supporting evidence and should not be routinely prescribed 3, 2, 1

Surgical and Interventional Options

• Surgery is indicated for recurrent pneumothoraces and isolated bullous disease 3, 2
• Lung volume reduction surgery (endobronchial valves or coils) may benefit selected patients with heterogeneous or homogenous emphysema and significant hyperinflation refractory to optimal medical care 3
• Lung transplantation should be considered in very severe COPD: BODE index 5-6, PCO2 >50 mmHg, PaO2 <60 mmHg, FEV1 <25% predicted 3

Travel Considerations

• Air travel may be hazardous if PaO2 breathing air is <6.7 kPa (50 mmHg)—check oxygen availability on flights 3, 2

Management of Exacerbations

An exacerbation is an acute worsening of respiratory symptoms requiring additional therapy, most commonly triggered by respiratory tract infections: 3

Classification of Exacerbations

• Mild: Treated with short-acting bronchodilators only 3
• Moderate: Treated with short-acting bronchodilators plus antibiotics and/or oral corticosteroids 3
• Severe: Requires hospitalization or emergency room visit, may be associated with acute respiratory failure 3

Acute Treatment

Short-acting inhaled β2-agonists, with or without short-acting anticholinergics, are the initial bronchodilators for acute exacerbations: 3, 1

Systemic corticosteroids improve FEV1, oxygenation, and shorten recovery time and hospitalization duration:

• Recommended dose: 40 mg prednisone daily for 5 days (not exceeding 5-7 days) 1
• Oral prednisolone is equally effective as intravenous administration 1
• Corticosteroids may be less efficacious in patients with lower blood eosinophil levels 1

Antibiotics should be used when indicated (increased breathlessness, increased sputum volume, AND purulent sputum):

• Antibiotics shorten recovery time and reduce risk of early relapse, treatment failure, and hospitalization duration 3

Non-invasive ventilation (NIV) should be the first mode of ventilation for acute respiratory failure: 3

Methylxanthines are not recommended due to side effects: 3

Post-Exacerbation Management

• Maintenance therapy with long-acting bronchodilators should be initiated as soon as possible before hospital discharge 3
• Appropriate measures for exacerbation prevention should be initiated 3
• Patients with frequent exacerbations (≥2 per year) have worse health status and require intensified therapy 3

Monitoring and Follow-Up

Routine follow-up is essential to monitor disease progression and modify management:

• Monitor symptoms, exacerbations, and objective airflow limitation measures at each visit 3, 1
• Each follow-up visit should include discussion of current therapeutic regimen 3, 1
• Assess for complications and comorbidities that may develop 3

Indications for Specialist Referral

Refer to pulmonary specialist for:

• Suspected severe COPD or onset of cor pulmonale 2
• Assessment for oxygen therapy or nebulizer use 2
• Assessment for oral corticosteroid treatment 2
• Bullous lung disease or consideration for surgery 2
• COPD in patients under 40 years or with <10 pack-years smoking history 2
• Rapid decline in FEV1 2
• Uncertain diagnosis or symptoms disproportionate to lung function 2
• Frequent infections to exclude bronchiectasis 2

Common Pitfalls to Avoid

• Never accept subjective improvement as an endpoint for corticosteroid trials—objective spirometric improvement must be documented 3, 2
• Do not prescribe short-burst oxygen for breathlessness without objective evidence of hypoxemia, as evidence supporting this practice is lacking 3, 2, 1
• Do not use LABA as monotherapy in COPD—always combine with anticholinergics or ICS 7
• Monitor for pneumonia in patients treated with inhaled corticosteroids 7
• Advise patients to rinse mouth with water without swallowing after ICS inhalation to reduce risk of oral candidiasis 7