Chronic obstructive airways disease

Question 1

Chronic obstructive airways disease

Answer 1

Please examine this patient’s chest; he has a chronic chest condition.

Question 2

Clinical signs

Answer 2

• Inspection: nebulizer/inhalers/sputum pot, dyspnoea, central cyanosis and pursed lips
• CO2 retention flap, bounding pulse and tar‐stained fingers
• Hyper‐expanded
• Percussion note resonant with loss of cardiac dullness
• Expiratory polyphonic wheeze (crackles if consolidation too) and reduced breath sounds at apices
• Cor pulmonale: raised JVP, ankle oedema, RV heave; loud P2 with pansystolic murmur of tricuspid reurgitation
• COPD does not cause clubbing: therefore, if present consider bronchial carcinoma or bronchiectasis

Question 3

Discussion of COPD

Answer 3

• Spectrum of disease with airway obstruction (with or without sputum production); can be low FEV1 at one end and emphysema with low O2 sats but normal spirometry at the other
• Degree of overlap with chronic asthma, although in COPD there is less reversibility (<15% change in FEV1 post‐bronchodilators)

Question 4

Causes of COPD

Answer 4

• Environmental: smoking and industrial dust exposure (apical disease)
• Genetic: α1‐antitrypsin deficiency (basal disease)

Question 5

Investigations for COPD

Answer 5

• CXR: hyper‐expanded and/or pneumothorax
• ABG: type II respiratory failure (low PaO2 high PaCO2)
• Bloods: high WCC (infection), low α1‐antitrypsin (younger patients/FH+), low albumin (severity)
• Spirometry: low FEV1, FEV1/FVC < 0.7 (obstructive)
• Gas transfer: low TLCO

Question 6

Treatment of COPD

Answer 6

• Medical – depends on severity (GOLD classification):
  ⚬⚬ Smoking cessation is the single most beneficial management strategy
  ⚬⚬ Cessation clinics and nicotine replacement therapy
  ⚬⚬ Long‐term oxygen therapy (LTOT)
  ⚬⚬ Pulmonary rehabilitation
  ⚬⚬ Mild (FEV1 >80) – beta‐agonists
  ⚬⚬ Moderate (FEV1 <60%) – tiotropium plus beta‐agonists
  ⚬⚬ Severe (FEV1 <40%) or frequent exacerbations -above plus inhaled corticosteroids; although avoid if patient has ever had an episode of pneumonia (TORCH trial)
  ⚬⚬ Exercise
  ⚬⚬ Nutrition (often malnourished)
  ⚬⚬ Vaccinations ‐ pneumoccoal and influenza
• Surgical (careful patient selection is important)
  ⚬⚬ Bullectomy (if bullae >1 L and compresses surrounding lung)
  ⚬⚬ Endobronchial valve placement
  ⚬⚬ Lung reduction surgery: only suitable for a few patient with heterogeneous distribution of emphysema
  ⚬⚬ Single lung transplant

Question 7

LONG-TERM OXYGEN THERAPY (LTOT )

Answer 7

• Inclusion criteria:
  ⚬⚬ Clinically stable, Non‐smoker with PaO2 <7.3 kPa on air despite max Rx –> Value should be measured on 2 different occasions 3 weeks apart
  ⚬⚬ If PaO2 7.3-8 Kpa + evidence of cor pulmonale, pulmonary HTN, polythycemia, or nocturnal hypoxia
  ⚬⚬ PaCO2 that does not rise excessively on O2
  ⚬⚬ For terminally ill patients
• 2–4 L/min via nasal prongs for at least 15 hours a day
• Improves average survival by 9 months

Question 8

Treatment of an acute exacerbation

Answer 8

• Controlled O2 via Venturi mask monitored closely
• Bronchodilators
• Antibiotics
• Steroids 7 days

Question 9

Prognosis

Answer 9

COPD patients with an acute exacerbation have 15% in‐hospital mortality

Question 10

Differential of a wheezy chest

Answer 10

• Granulomatous polyarteritis (previously Wegner’s): saddle nose; obliterative bronchiolitis
• Rheumatoid arthritis: wheeze secondary to obliterative bronchiolitis
• Post‐lung transplant: obliterative bronchiolitis as part of chronic rejection spectrum