All About Asthma
Asthma is a chronic, inflammatory disease in which the airways become sensitive to allergens (any substance that triggers an allergic reaction). Several things happen to the airways when a child is exposed to certain triggers:
- The lining of the airways becomes swollen and inflamed.
- The muscles that surround the airways tighten.
- The production of mucus is increased, leading to mucus plugs.
All of these factors will cause the airways to narrow, thus making it difficult for air to go in and out of your child's lungs and causing the symptoms of asthma.
According to the latest information available from the CDC and the EPA:
- Approximately 25 million people in the U.S. have been diagnosed with asthma, with at least 7 million of them children under the age of 18.
- Asthma is one of the leading, serious, chronic illnesses among children in the U.S.
- Asthma accounts for 10.5 million absences from school each year.
- Asthma is the third-ranking cause of hospitalizations of children under the age of 15.
The exact cause of asthma is not completely known. It is believed to be partially inherited, but it also involves many other environmental, infectious, and chemical factors.
After a child is exposed to a certain trigger, the body releases histamine and other agents that can cause inflammation in your child's airways. The body also releases other factors that can cause the muscles of the airways to tighten, or become smaller. There is also an increase in mucus production that may clog the airways.
Some children have exercise-induced asthma, which is caused by varying degrees of exercise. Symptoms can occur during, or shortly after, exercise. Each child has different triggers that cause the asthma to worsen. You should discuss this with your child's doctor.
The changes that occur in asthma are believed to happen in two phases:
- An immediate response to the trigger leads to swelling and narrowing of the airways. This makes it initially difficult for your child to breathe.
- A later response, which can happen four to eight hours after the initial exposure to the allergen, leads to further inflammation of the airways and obstruction of airflow.
The following are the most common symptoms of asthma. However, each child may experience symptoms differently. Symptoms may include:
- Coughing. This can be either constant or intermittent.
- Wheezing. A whistling sound that may be heard while your child is breathing.
- Trouble breathing or shortness of breath while your child is playing or exercising
- Chest tightness. Your child may say his or her chest hurts or does not feel good.
- Nighttime cough
- Noisy breathing
The symptoms of asthma may resemble other problems or medical conditions. Always consult your child's doctor for a diagnosis.
Although anyone may have asthma, it most commonly occurs in:
- Children and adolescents ages five to 17 years
- A child with a family history of asthma
- Children who have allergies
- Children who have exposure to secondhand tobacco smoke
Children with asthma have acute episodes when the air passages in their lungs become narrower, and breathing becomes more difficult. These problems are caused by an oversensitivity of the lungs and airways:
- The lungs and airways overreact to certain triggers causing:
- The lining of the airways to become inflamed and swollen
- Tightening of the muscles that surround the airways
- An increased production of mucus
- Breathing becomes harder and may hurt
- There may be coughing
- There may be a wheezing or whistling sound, which is typical of asthma. Wheezing occurs because of the rush of air that moves through the narrowed airways.
To diagnose asthma and distinguish it from other lung disorders, doctors rely on a combination of medical history, physical examination, and laboratory tests, which may include:
- Spirometry. A spirometer is a device used by your child's doctor that assesses lung function. Spirometry, the evaluation of lung function with a spirometer, is one of the simplest, most common pulmonary function tests and may be necessary for any or all of the following reasons:
- To determine how well the lungs receive, hold, and utilize air
- To monitor a lung disease
- To monitor the effectiveness of treatment
- To determine the severity of a lung disease
- To determine whether the lung disease is restrictive (decreased airflow) or obstructive (disruption of airflow)
- Peak flow monitoring (PFM). A device used to measure the amount of air a person can blow out of the lungs. During an asthma or other respiratory flare-up, the large airways in the lungs slowly begin to narrow. This will slow the speed of air leaving the lungs and can be measured by a PFM. This measurement is very important in evaluating how well or how poorly the disease is being controlled.
- Chest X-rays. A diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.
- Blood tests. These tests analyze the amount of carbon dioxide and oxygen in the blood.
- Allergy tests
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Online Resources of Respiratory Disorders