what is asthma?

Asthma bronchiole

Asthma affect 5-8% of the population. It is characterized by recurrent episodes of dyspnoea, cough usually at night, and wheeze caused by reversible airways obstruction.

The difference between asthma and COPD is that asthma is reversible bronchoconstriction.

When examine patient with astma , pulsus parodoxus may be noted.

Treatment:

1.       Stimulate sympathetic system to open the airways using B agonist.(B2 receptor)

2.       Inhibit parasympathetic systemusing anticholinergic

3.       Reduce inflammation using glucocorticoids.

There are 2 types of astma:

1.       Allergic astma-predominatly occur to children. This results from sensitization to allergens. when there is exposure to allergen,  stimulation of IgE OCCURS. THEN IgE bind to mast cells. When there is next exposure to allergen, it will be detected by mast cells that bind to ige, reeleasing histamine. Histamine cause mucus secretion , inflammation, vascular permeability and bronchospasm and lead to narrowing of airways.

2.       Idiopathic asthma. Usually occur after 40 years old. Usually occur after infections.