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Asthma
Definition
Asthma is an inflammatory
disease of the airways in the lungs that is characterized by periodic
attacks of wheezing, shortness of breath, coughing and chest tightness.
During these attacks, inflammation in the airways causes decreased
airflow into and out of the lungs. In addition, the muscles lining
the airways constrict causing the airways to narrow (bronchoconstriction),
which causes the characteristic wheezing sound, and mucus production
in the airways is increased.
Asthma attacks can last minutes or
days and can become dangerous if the airflow becomes too severely
restricted.
Causes, incidence & risk
factors
Asthma symptoms
may be triggered by inhaled allergens (allergy triggers) such as
pollens, dust, molds, pet dander, perfumes, smoke, dust mites, grass
etc. Asthma symptoms can also be triggered by cold air, exercise,
respiratory infections, stress or even certain types of medications.
Asthma
may be diagnosed in childhood or adulthood. In most people, asthma
symptoms decrease over time, but for some, symptoms actually get
worse. A large majority of people (but not all) with asthma have
a family member with asthma, allergies or eczema.
Symptoms
Wheezing
- Usually begins suddenly
- Is
episodic
- May
be worse at night or in the early morning
- May
be aggravated by exposure to cold air, exercise, heartburn
- May
resolve spontaneously
- Is
relieved by bronchodilator medications
Cough
- With
or without sputum production
Shortness
of breath
- Inability
to take a deep breath or exhale completely
- Decreased
exercise tolerance
Intercostal
retractions (pulling of the skin between the ribs with breathing)
Chest tightness
EMERGENCY SYMPTOMS
- Extreme difficulty breathing
- Bluish
color to the lips and face
- Severe
anxiety due to shortness of breath
- Rapid
pulse
- Decreased
level of consciousness
Tests
Tests that may be done to help diagnose and treat asthma include:
- Pulmonary function tests
- Peak
flow measurements
- Chest
x-ray
- Allergy
testing
- Arterial
blood gas testing
- Eosinophil
count ( a type of white blood cell that is often increased
with asthma)
Treatment
Treatment has two goals: (1) avoidance of
triggers (2) controlling severity and frequency of symptoms.
Two groups of medications are used to control the
severity and frequency of asthma symptoms:
Short-term (rescue)
medications
- Short-acting bronchodilators
(i.e. albuterol, Xopenex)
- Oral
or intravenous steroids
Long-term (maintenance)
medications
- Long-acting
bronchodilators (i.e. Serevent, Foradil) which help
open airways
- Leukotriene
inhibitors (Singulair, Accolate) which modify the
immune response
- Anticholinergics
(iIpratropium, tiotropium) which help prevent bronchoconstriction
- Cromolyn
or theophylline
- Inhaled
steroids (Flovent, Azmacort) which help reduce
airway inflammation
- Anti-IgE
therapy (Xolair), which is new injectable
medication that is used to modify the immune response in
severe asthma.
The
types, dosage, and frequency of medications used in the treatment
of asthma depends on the severity and frequency of symptoms. People
who are only having occasional mild symptoms may only need a rescue
medication, whereas, those with more frequent and severe symptoms
may need several different short-acting and long-acting medications.
A
peak flow meter is a simple device that is used to measure lung volumes,
can be used on a regular basis to track asthma symptoms and is often
a good early indicator of an asthma flare-up.
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