Give your own definition of COPD.

• Chronic Obstructive pulmonary disease is an inflammatory airway disease characterized by the presence of Bronchial asthma, chronic bronchitis and emphysema and their characteristics in varying degrees. It cannot be cured but the symptoms can be lessened as response to treatment is generally poor. It is also characterized by progressive loss of lung function that leads to difficulty breathing

Briefly describe the proposed aetiology and pathophysiology of chronic bronchitis and emphysema.

• The proposed cause of Chronic Bronchitis and emphysema is believed to be an abnormal inflammatory response due to noxious particles/gases such as cigarette smoke (directly linked – but other irritants can have this effect as well). The prolongation of the presence of the irritant leads to a higher incidence even if the irritant is then removed at a later stage.
• Chronic bronchitis is characterized by increased mucus secretion, decreased mucosal clearance, frequent bacterial respiratory infections, structural changes in the bronchial walls (which negatively affects gaseous exchange) and sticky mucus due to decreased clearance.
• Emphysema is characterized by the irreversible dilation of respiratory bronchioles and alveoli due to structural damage. This effectively “traps” air within the lungs as the bronchioles lose their elasticity due to damage – making them ineffective during respiration. Exhalation is thus difficult and decreased capillary blood vessels (due to damage to infrastructure) impede gas exchange.

Which types of therapy are included in the treatment of a COPD patient?

• Treatment mainly is for symptoms/secondary diseases
  • You need to stop smoking
  • You need to get immunized against influenza ( as chronic bronchitis causes frequent bacterial infections) and you need to use broad spectrum antibiotics when you get infections.
  • Bronchodilators are used to treat airway obstructions
  • Increased mucus secretions and sticky mucus is treated by diluting the mucus with rehydration and steam. (using nebulizer)
  • Hypoxia is treated with oxygen inhalation
  • Poor lung capacity is increased with light to moderate exercise (this could also lead to decreased incidence of hypoxia
  • Surgery - Lung transplantation
  • Corticosteroids can also help (don’t work often but helps sometimes)

Why is ipratropium more effective in the treatment of chronic bronchitis than in the treatment of bronchial asthma?

• chronic bronchitis is characterized by increased mucus secretion, whereas in bronchial asthma, even though there is a formation of mucus plugs, the main causative of asthma is reduced airflow due to broncho constriction.
• Ipratropium is a competitive inhibitor of muscarinic receptors (M3 – type) on bronchial smooth muscle – it thus works by antagonising Ach action – preventing an increase in intracellular calcium concentrations – leading to bronchodilation and decrease in nasal and bronchial gland secretions. It unfortunately also decreases mucociliary clearance – which would have helped with mucus plugs.
• It thus is more effective in chronic bronchitis because of the effect it has on the mucus secretions – as it is equally effective in both diseases regarding its broncho-dilatory effects.

In which way do the skeletal muscle effects of theophylline have advantages in the treatment of COPD?

• Theophylline strengthens the contraction of the skeletal smooth muscle – diaphragm – thus increasing the ventilatory capacity.

What is the role of oxygen therapy in COPD?

Oxygen therapy is simply there to decrease signs of hypoxia, as gaseous exchange is impeded within the lungs – thus increasing the amount of oxygen taken into the lungs will directly impact the amount of oxygen exchange within the lungs – decreasing the signs of hypoxia by increasing the oxygen within the body. It does not have any structural function or interact with any drugs whatsoever. It simply increases your oxygen intake and uptake