Respiratory Pathology

• What are the 2 diseases that make up COPD?

  Chronic bronchitis (affects bronchi)

  Emphysema (affects alveoli)
• What is chronic bronchitis?

  Productive cough on most days > 3 months of the year for 2 consecutive years

  Chronic inflam of lower resp tract -> excessive mucous secretion, cough, dyspnoea & loss of mucociliary apparatus (decreased mucous clearance) -> reduced airway radius & increased resistance
• What is emphysema?

  Damage to alveoli -> air space enlargement

  Destruction of lung parenchyma

  Loss of lung elasticity & small airway closure

  -> Reduced airway radius & increased resistance
• What is COPD strongly associated with?

  Cigarette smoking

  Air pollution
• What are the 3 primary symptoms of COPD?

  Productive cough

  Sputum production

  SOB on exertion
• RFs of COPD

  Smoke exposure (inc. second-hand & passive exposure)

  Air pollution

  Occupational dusts & chemicals

  Frequent lower resp tract infections during childhood
• What is shown in the image?

  Emphysema

  
• Inflammation in COPD 


  Tobacco smoke -> neutrophils & macrophages released -> elastase release (usually to digest microbes) -> breakdown elastin in lung parenchyma (usually protected by alpha-1 antitrypsin (AAT), but excess elastase overcomes this)

  Smoking can also oxidise part of AAT -> reduced AAT function
• If pt seen with COPD under 50, need to be screened for AAT deficiency (< 1% of COPD cases).
• What tool can be used to grade SOB?

  MRC Dyspnoea Scale

  
• What are the Inx of COPD?

  Obs

  Full Hx & examination

  PEFR

  Bloods (FBC, ABG)

  CXR

  Spirometry
• What are the goals of effective COPD management?

  Slow disease progression

  Relieve symptoms

  Improve exercise tolerance

  Improve health status

  Prevent & treat complications

  Prevent & treat exacerbations

  Reduce mortality