|
| ANATOMY |
| Air
enters the respiratory system through the nose (nasopharynx) and mouth
(oropharynx) and passes through the larynx (voice box) into the trachea.
At the carina, the trachea branches into the left and right main stem
bronchus. The bronchioles branch off of the bronchi and terminate in a
cluster of tiny air sacs called the alveoli. The alveoli are covered with
capillaries which receive the oxygen from the air in the alveoli and diffuse
the carbondioxide into the alveoli to be exhaled. |
| 
NORMAL |
What
is asthma? |
ASTHMATIC
|
| Asthma
is reactive airway disease, a disease in which the smaller airways react
in response to a trigger such as an allergen or an irritant. It is airway
hypersensitivity with recerrent, reversible airway inflammation, broncho-constriction
(bronchospasm), and mucus gland secretion and hypertrophy (enlargement)
of the bronchial muscle. Asthma is a chronic-episodic order: The underlying
predisposition to asthma may be chronic, but attacks occur episodically
in response to some type of trigger. |
| Compare
the normal bronchus on the left with the asthmatic bronchus on the right. |
| Bronchospasm
is usually characterized by wheezes and prolonged expiration. The normal
respiratory cycle is about 1/3 inspiration and 2/3 expiration, or an inspiration/expiration
ratio of 1:2. In the asthmatic experiencing bronchospasm, the inspiration/expiration
increases to, for example, 1:4 due to the prolonged expiratory phase. |
| Cardiac
Asthma is a term sometimes used to describe congestive heart failure
(CHF). While CHF patients usually have a chief complaint of difficulty breathing
and have copious amounts of fluid in the lungs, they do not have the bronchospasm
associated with respiratory asthma. A key difference in the presentation
of CHF is that most patients maintain an inspiration/expiration ratio of
1:1 or 1:2 rather than experience the prolonged expiration phase of bronchospasm. |
| |
| Common
Asthma Triggers |
| Allergens:
Cats/cat hair - Dogs/dog hair - feathers - foods - grass - hay - house dust
(mites) - medications - molds - pollen - roaches - trees - weeds |
| Chemicals:
Colognes/perfumes - cosmetics/hair sprays/lotions - detergents/soaps - vehicle
exhaust fumes - household & industrial cleaners - outside dust - paint
products/strippers/thinners |
| Weather:
Cold weather - rapid temperature changes - in and out of buildings temperature
changes |
| Emotional
Stress |
| Infections,
especially respiratory infections |
| Ingestants:
alcohol - spicy foods |
| Irritants:
Tobacco smoke - smoke from burning - harsh chemicals |
| Physical
Exercise (exercise induced asthma) |
Asthma
Statistics |
Seniors
