Asthma

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Alternative names

Bronchial asthma; Exercise-induced asthma
Definition

Asthma is an inflammatory disorder of the airways, which causes attacks of wheezing, shortness of breath, chest tightness, and coughing.

Causes, incidence, and risk factors

Asthma is caused by inflammation in the airways. When an asthma attack occurs, the muscles surrounding the airways become tight and the lining of the air passages swell. This reduces the amount of air that can pass by, and can lead to wheezing sounds.

Most people with asthma have wheezing attacks separated by symptom-free periods. Some patients have long-term shortness of breath with episodes of increased shortness of breath. Still, in others, a cough may be the main symptom. Asthma attacks can last minutes to days and can become dangerous if the airflow becomes severely restricted.

In sensitive individuals, asthma symptoms can be triggered by breathing in allergy-causing substances (called allergens or triggers). Triggers include pet dander, dust mites, cockroach allergens, molds, or pollens. Asthma symptoms can also be triggered by respiratory infections, exercise, cold air, tobacco smoke and other pollutants, stress, food, or drug allergies. Aspirin and other non-steroidal anti-inflammatory medications (NSAIDS) provoke asthma in some patients.

Approximately 20.5 million Americans currently have asthma. Many people with asthma have an individual or family history of allergies, such as hay fever (allergic rhinitis) or eczema. Others have no history of allergies.

Symptoms
Wheezing
Usually begins suddenly
Comes in episodes
May be worse at night or in early morning
Gets worse with cold aira, exercise, and heartburn (reflux)
May go away on its own
Is relieved by bronchodilators (drugs that open the airways)
Cough with or without sputum (phlegm) production
Shortness of breath that gets worse with exercise or activity
Intercostal retractions (pulling of the skin between the ribs when breathing)
Emergency symptoms:

Extreme difficulty breathing
Bluish color to the lips and face
Severe anxiety due to shortness of breath
Rapid pulse
Sweating
Decreased level of alertness, such as severe drowsiness or confusion, during an asthma attack
Additional symptoms that may be associated with this disease:

Nasal flaring
Chest pain
Tightness in the chest
Abnormal breathing pattern --breathing out takes more than twice as long as breathing in
Breathing temporarily stops
Signs and tests
Allergy testing may be helpful in identifying allergens in patients with persistent asthma. Common allergens include pet dander, dust mites, cockroach allergens, molds, and pollens. Common respiratory irritants include tobacco smoke, pollution, and fumes from burning wood or gas.

The doctor will use a stethoscope to listen to the lungs. Asthma-related sounds may be heard. However, lung sounds are usually normal between asthma episodes.

Tests may include:

Lung function tests
Peak flow measurements
Chest x-ray
Blood tests, including eosinophil count (a type of white blood cell)
Arterial blood gas
Treatment

Treatment is aimed at avoiding known allergens and respiratory irritants and controlling symptoms and airway inflammation through medication.

There are two basic kinds of medication for the treatment of asthma:

Long-term control medications are used on a regular basis to prevent attacks, not for treatment during an attack. Types include:

Inhaled steroids (such as Azmacort, Vanceril, AeroBid, Flovent) prevent inflammation
Leukotriene inhibitors (such as Singulair and Accolate)
Anti-IgE therapy (Xolair), a medicine given by injection to patients with more severe asthma
Long-acting bronchodilators (such as Serevent) help open airways
Cromolyn sodium (Intal) or nedocromil sodium
Aminophylline or theophylline (not used as frequently as in the past)
Sometimes a combination of steroids and bronchodilators are used, using either separate inhalers or a single inhaler (such as Advair Diskus).

Quick relief, or rescue, medications are used to relieve symptoms during an attack. These include:

Short-acting bronchodilators (inhalers), such as Proventil, Ventolin, Xopenex, and others.
Corticosteroids, such as prednisone or methylprednisolone) given by mouth or into a vein
Persons with mild asthma (infrequent attacks) may use quick relief medication as needed. Those with persistent asthma should take control medications on a regular basis to prevent symptoms. A severe asthma attack requires a medical evaluation and may require a hospital stay, oxygen, and intravenous medications.

A peak flow meter, a simple device to measure lung volume, can be used at home to help you "see an attack coming" and take the appropriate action, sometimes even before any symptoms appear. If you are not monitoring asthma on a regular basis, an attack can take you by surprise.

Peak flow measurements can help show when medication is needed, or other action needs to be taken. Peak flow values of 50-80% of an individual’s personal best results indicate a moderate asthma attack, while values below 50% indicate a severe attack.

Support Groups

The stress caused by illness can often be helped by joining a support group, where members share common experiences and problems. See asthma and allergy - support group.

Expectations (prognosis)

There is no cure for asthma, though symptoms sometimes decrease over time. With proper self management and medical treatment, most people with asthma can lead normal lives.

Complications
Respiratory fatigue
Side effects of asthma medications
Pneumothorax
Death
Calling your health care provider
Call for an appointment with your health care provider if you or your child experience mild asthma symptoms (to discuss treatment options).

Call your health care provider (or go to the emergency room) for moderate shortness of breath (shortness of breath with talking, peak flow 50-80% of personal best), if symptoms worsen or do not improve with treatment, or an attack requires more medication than recommended in the prescription.

Go to the emergency room for severe shortness of breath (shortness of breath at rest, peak flow less than 50% of personal best), if drowsiness or confusion develops, or for severe chest pain.

Prevention

Asthma symptoms can be substantially reduced by avoiding known allergens and respiratory irritants. If someone with asthma is sensitive to dust mites, exposure can be reduced by encasing mattresses and pillows in allergen-impermeable covers, removing carpets from bedrooms, and by vacuuming regularly. Exposure to dust mites and mold can be reduced by lowering indoor humidity.

If a person is allergic to an animal that cannot be removed from the home, the animal should be kept out of the patient's bedroom. Filtering material can be placed over the heating outlets to trap animal dander. Exposure to cigarette smoke, air pollution, industrial dusts, and irritating fumes should also be avoided.

Allergy desensitization may be helpful in reducing asthma symptoms and medication use, but the size of the benefit compared with other treatments is not known.


Asthma (say: az-muh) is a condition that affects a person's airways, which are also called breathing tubes or bronchial (say: brong-kee-ul) tubes. These tubes lead from the windpipe, or trachea (say: tray-kee-uh), into the lungs. For most kids, breathing is simple: They breathe in through their noses or mouths and the air goes into the windpipe. From there, it travels through the airways and into the lungs. But for kids with asthma, breathing can be a lot more difficult because their airways are very sensitive.

An asthma flare-up, which some people call an asthma attack or episode, happens when a person's airways get swollen and narrower and it becomes a lot harder for air to get in and out of the lungs. Sometimes the swollen airways produce extra mucus, which makes things pretty sticky, so it's easy to see why it's hard to breathe.

In between flare-ups, a kid's breathing can be totally normal or seem that way. But during a flare-up, it can feel like the person is breathing through a straw. A kid with asthma may wheeze (a whistling sound when he or she breathes), cough, and feel tightness in the chest. An asthma flare-up can get worse and worse if a kid doesn't use asthma medicine. After an asthma flare-up, the airways almost always return to the way they were before, although it can take several days.

Who Gets Asthma?
Asthma is more common than you might think. As many as 6 million kids in the United States have it. Asthma affects about one or two kids out of 10. That means if you have 20 kids in your class, two to four of them might have asthma. Asthma can start at any age - even in a little baby or an adult - but it's most common in school-age kids.

No one really knows why one person's airways are more sensitive than another person's, but we do know that asthma runs in families. That means if a kid has asthma, he or she may also have a parent, sibling, uncle, or other relative who has asthma or had it as a child.

Asthma flare-ups may sound a little like a cold, with coughing and wheezing, but asthma isn't contagious. You can't catch it from someone like you can catch a cold.

What Causes an Asthma Flare-Up?
Different kids have different triggers - things that set off asthma flare-ups. There are a lot of triggers. Some kids are sensitive to allergens (say: ah-lur-jenz), substances that cause allergic reactions in the airways. Common allergens for kids with asthma include dust mites (tiny bugs that live in dust), mold (if you've ever been in a damp basement and smelled something funny, it was probably mold), and pollen (from trees, grass, and weeds).

A lot of kids have asthma flare-ups when they are near furry animals. Cats and dogs both have what's called animal dander in their fur. This is sort of like dandruff, and it's a trigger that can cause a powerful reaction in the airways.

Some substances can trigger flare-ups because they really irritate the airways. These include perfume, chalk dust, and cigarette smoke. Smoking is always a bad idea, especially around someone who has asthma.

Sometimes an infection can be a trigger and set off an asthma flare-up. If a kid comes down with a cold or the flu, his or her airways may become more sensitive than usual. In some kids, cold air itself can cause an asthma flare-up, and so can exercise. In fact, some kids have what's called exercise-induced asthma. This means they have breathing problems only when they exercise.

How Is Asthma Treated?
Kids who have asthma should try to avoid things that can cause their airways to tighten. But some triggers - like cats, colds, and chalk dust - can't always be avoided. That's why kids who are sensitive to those things must manage their asthma by taking medication.

Not every kid's asthma is the same, so there are different medicines for treating it. It's not like curing a sore throat or an earache, when everybody gets the same medicine. Instead, the doctor will think about what causes the asthma flare-ups, how fast the flare-ups happen, and how serious they are. Then he or she will decide on the best kind of treatment.

Some kids need to take asthma medication only once in a while, when they have a flare-up. This is called rescue medicine because it works fast to open the airways, so the person can breathe. Other kids may need to take controller medicine every day. Controller medicine works to keep flare-ups from happening.


A kid who knows in advance that he or she will be around allergens or other triggers may need to take medication ahead of time that will keep the airways open. And kids who have exercise-induced asthma can take medication before exercising so they'll be able to finish all their laps around the track. Whatever their triggers are, kids who have asthma can use a peak flow meter to get an idea of how well they are breathing that day and whether they need to take any medicine.

Asthma medicine often is taken through an inhaler (say: in-hay-lur). An inhaler is a plastic tube that holds a container of medicine. You may have seen a friend or someone in school using an inhaler, which is held up to the mouth. A kid holds the inhaler up to his or her mouth and breathes in. The medicine comes out in a mist that goes into the lungs. The medicine in the mist relaxes the airways, so the person can breathe easier.

Space Out With a Spacer
Sometimes a kid uses an inhaler and something called a spacer. A spacer is a piece that attaches to the inhaler and holds the mist in one place, between the inhaler and the kid's mouth. It lets the kid breathe in when he or she is ready, so it's easier to inhale all the medication.

Sometimes kids take other asthma medicines by swallowing them. Whatever medications a kid takes, the goal is always the same: to get the asthma flare-ups under total control, so the triggers don't create problems.

A lot of kids find their asthma goes away or becomes less serious as they get older. Some doctors think this happens because the airways grow wider as a kid grows up and gets bigger. With more room in the airways, the air has an easier time getting in and out.

Some people do have asthma as adults, but it doesn't have to slow them down. Plenty of Olympic athletes and other sports stars manage their asthma, but keep on playing!