Give your own definition of COPD:

COPD refers to a variety of combinations of different diseases that cause airflow blockage (limit pulmonary airflow) and gas exchange this causes a difficulty in breathing. These different diseases are: Bronchial asthma, chronic bronchitis and emphysema. 

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

Chronic bronchitis:
Non-specific COPD. The cause of chronic bronchitis is usually long-term exposure to irritants such as cigarette smoke. Chronic bronchitis is thought to be caused by overproduction and hypersecretion of mucus by goblet cells and the decrease in mucus clearance . Epithelial cells lining the airway respond to toxic, infectious stimuli by releasing inflammatory mediators and eg pro-inflammatory cytokines. Regular respiratory bacterial infections occur due to the increased mucus which promotes the growth of bacteria. Structural changes to the bronchial walls also takes place since airways get tight, swollen and filled with mucus. Due to this thick mucus, chronic cough manifests. 

Emphysema:
Disease that is caused by long term exposure to airborne irritants, the most common being inhaled smoke. It is characterised by the irreversible dilation of respiratory bronchioles and alveoli due to structural damage. Expiration is proven to be difficult due to air being trapped in the lungs (no way for new air to come in) The capillary blood vessels which surrounds the alveoli delays gaseous exchange which results in a build up of CO2. This can lead to hypoxic conditions. 

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

Smoking cessation: 
Prevents progression of disease. Psychotherapy, consultation, encouragement and support can help the patient to stop their smoking habit. (Drugs containing nicotine should be avoided for a period of time)

Bacterial infection: 
Influenza immunization which prevents secondary infections.
Broad spectrum antibiotics.

Obstruction of airflow:
Bronchodilators, M-antagonists are usually first line in COPD (tiotropium and ipratropium), Beta-2 agonists can also be used as well as theophylline. If unsuccessful, corticosteroids can also be administered. 

Mucus secretions:
Dilute mucus with rehydration and steam

Hypoxia: 
oxygen inhalation 

Poor lung capacity:
Light to moderate exercise. 

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

Chronic bronchitis is usually associated with increased parasympathetic nervous system activity. Since Ipratropium is an anticholinergic drug, this activity will be blocked. A reduction in bronchospasm caused by parasympathetic activity will be observed. (bronchodilation)

Bronchial asthma is mostly caused by inflammatory messengers which cause inflammation in the lungs and is followed by bronchospasm. Ipratropium can still relieve bronchoconstriction, but not as effectively. 

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

Theophylline strengthens the contraction of the diaphragm skeletal muscles which improves the ventilation response and reduces hypoxia and dyspnea in COPD patients. 

What is the role of oxygen therapy in COPD?

Oxygen is used to treat hypoxic conditions caused by impaired gaseous exchange found in COPD. This therapy increases oxygen in your lungs and bloodstream- more oxygen in capillaries of the lungs, therefore more oxygen can be provided to the body.