Asthma

Overview

Asthma is a disease that affects the breathing passages of the lungs (bronchioles). Asthma is caused by chronic (ongoing, long-term) inflammation of these passages. This makes the breathing passages, or airways, of the person with asthma highly sensitive to various "triggers."

• When the inflammation is "triggered" by any number of external and internal factors, the passages swell and fill with mucus.
• Muscles within the breathing passages contract (bronchospasm), causing even further narrowing of the airways.
• This narrowing makes it difficult for air to be breathed out (exhaled) from the lungs.
• This resistance to exhaling leads to the typical symptoms of an asthma attack.

Because asthma causes resistance, or obstruction, to exhaled air, it is called an obstructive lung disease. The medical term for such lung conditions is chronic obstructive pulmonary disease or COPD. COPD is actually a group of diseases that includes not only asthma but also chronic bronchitis and emphysema.

Like any other chronic disease, asthma is a condition you live with every day of your life. You can have an attack any time you are exposed to one of your triggers. Unlike other chronic obstructive lung diseases, asthma is reversible.

• Asthma cannot be cured, but it can be controlled.
• You have a better chance of controlling your asthma if it is diagnosed early and treatment is begun right away.
• With proper treatment, people with asthma can have fewer and less severe attacks.
• Without treatment, they will have more frequent and more severe asthma attacks and can even die.

Asthma is on the rise in the United States and other developed countries. We are not sure exactly why this is, but these factors may contribute.

• We grow up as children with less exposure to infection than did our ancestors, which has made our immune systems more sensitive.
• We spend more and more time indoors, where we are exposed to indoor allergens such as dust and mold.
• The air we breathe is more polluted than the air most of our ancestors breathed.
• Our lifestyle has led to our getting less exercise and an epidemic of obesity. There is some evidence to suggest an association between obesity and asthma.

Asthma is a very common disease in the United States, where more than 17 million people are affected. A third of these are children. Asthma affects all races and is slightly more common in African Americans than in other races.

• Asthma affects all ages, although it is more common in younger people. The frequency and severity of asthma attacks tend to decrease as a person ages.
• Asthma is the most common chronic disease of children.

Asthma has many costs to society as well as to the individual affected.

• Many people are forced to make compromises in their lifestyle to accommodate their disease.
• Asthma is a major cause of work and school absence and lost productivity.
• Asthma is one of the most common reasons for emergency department visits and hospitalization.
• Asthma costs the U.S. economy nearly $13 billion each year.
• Approximately 5,000 people die of asthma each year in this country.

The good news for people with asthma is that you can live your life to the fullest. Current treatments for asthma, if followed closely, allow most people with asthma to limit the number of attacks they have. With the help of your health-care provider, you can take control of your care and your life.

Asthma Causes

The exact cause of asthma is not known.

• What all people with asthma have in common is chronic airway inflammation and excessive airway sensitivity to various triggers.
• Research has focused on why some people develop asthma while others do not.
• Some people are born with the tendency to have asthma, while others are not. Scientists are trying to find the genes that cause this tendency.
• The environment you live in and the way you live partly determine whether you have asthma attacks.

An asthma attack is a reaction to a trigger. It is similar in many ways to an allergic reaction.

• An allergic reaction is a response by the body's immune system to an "invader."
• When the cells of the immune system sense an invader, they set off a series of reactions that help fight off the invader.
• It is this series of reactions that causes the production of mucus and bronchospasms. These responses cause the symptoms of an asthma attack.
• In asthma, the "invaders" are the triggers listed below. Triggers vary among individuals.
• Because asthma is a type of allergic reaction, it is sometimes called reactive airway disease.

Each person with asthma has his or her own unique set of triggers. Most triggers cause attacks in some people with asthma and not in others. Common triggers of asthma attacks are the following:

• exposure to tobacco or wood smoke,
• breathing polluted air,
• inhaling other respiratory irritants such as perfumes or cleaning products,
• exposure to airway irritants at the workplace,
• breathing in allergy-causing substances (allergens) such as molds, dust, or animal dander,
• an upper respiratory infection, such as a cold, flu, sinusitis, or bronchitis,
• exposure to cold, dry weather,
• emotional excitement or stress,
• physical exertion or exercise,
• reflux of stomach acid known as gastroesophageal reflux disease, or GERD,
• sulfites, an additive to some foods and wine, and
• menstruation: In some, not all, women, asthma symptoms are closely tied to the menstrual cycle.

Risk factors for developing asthma:

• hay fever (allergic rhinitis) and other allergies -- this is the single biggest risk factor;
• eczema: another type of allergy affecting the skin; and
• genetic predisposition: a parent, brother, or sister also has asthma.

Asthma Symptoms

When the breathing passages become irritated or infected, an attack is triggered. The attack may come on suddenly or develop slowly over several days or hours. The main symptoms that signal an attack are as follows:

• wheezing,
• breathlessness,
• chest tightness,
• coughing, and
• difficulty speaking.

Symptoms may occur during the day or at night. If they happen at night, they may disturb your sleep.

Wheezing is the most common symptom of an asthma attack.

• Wheezing is a musical, whistling, or hissing sound with breathing.
• Wheezes are most often heard during exhalation, but they can occur during breathing in (inhaling).
• Not all asthmatics wheeze, and not all people who wheeze are asthmatics.

Current guidelines for the care of people with asthma include classifying the severity of asthma symptoms, as follows:

• Mild intermittent: This includes attacks no more than twice a week and nighttime attacks no more than twice a month. Attacks last no more than a few hours to days. Severity of attacks varies, but there are no symptoms between attacks.
• Mild persistent: This includes attacks more than twice a week, but not every day, and nighttime symptoms more than twice a month. Attacks are sometimes severe enough to interrupt regular activities.
• Moderate persistent: This includes daily attacks and nighttime symptoms more than once a week. More severe attacks occur at least twice a week and may last for days. Attacks require daily use of quick-relief (rescue) medication and changes in daily activities.
• Severe persistent: This includes frequent severe attacks, continual daytime symptoms, and frequent nighttime symptoms. Symptoms require limits on daily activities.

Just because a person has mild or moderate asthma does not mean that he or she cannot have a severe attack. The severity of asthma can change over time, either for better or for worse.

When to Seek Medical Care

If you think you or your child may have asthma, make an appointment with your health-care provider. Some clues pointing to asthma include the following:

• wheezing,
• difficulty breathing,
• pain or tightness in your chest, and
• recurrent, spasmodic cough that is worse at night.

If you or your child has asthma, you should have an action plan worked out in advance with your health-care provider. This plan should include instructions on what to do when an asthma attack occurs, when to call the health-care provider, and when to go to a hospital emergency department. The following are general guidelines only. If your provider recommends another plan for you, follow that plan.

• Take two puffs of an inhaled beta-agonist (a rescue medication), with one minute between puffs. If there is no relief, take an additional puff of inhaled beta-agonist every five minutes. If there is no response after eight puffs, which is 40 minutes, your health-care provider should be called.
• Your provider also should be called if you have an asthma attack when you are already taking oral or inhaled steroids or if your inhaler treatments are not lasting four hours.

Although asthma is a reversible disease, and treatments are available, people can die from a severe asthma attack.

• If you are having an asthma attack and have severe shortness of breath or are unable to reach your health-care provider in a short period of time, you must go to the nearest hospital emergency department.
• Do not drive yourself to the hospital. Have a friend or family member drive. If you are alone, call 911 immediately for emergency medical transport.

Exams and Tests

If you go to the emergency department for an asthma attack, the health care provider will first assess how severe the attack is. Attacks are usually classified as mild, moderate, or severe. This assessment is based on several factors:

• symptom severity and duration,
• degree of airway obstruction, and
• the extent to which the attack is interfering with regular activities.

Mild and moderate attacks usually involve the following symptoms, which may come on gradually:

• chest tightness,
• coughing or spitting up mucus,
• restlessness or trouble sleeping, and
• wheezing.

Severe attacks are less common. They may involve the following symptoms:

• breathlessness,
• difficulty talking,
• tightness in neck muscles,
• slight gray or bluish color in your lips and fingernail beds,
• skin appear "sucked in" around the rib cage, and
• "silent" chest (no wheezing on inhalation or exhalation)
.

If you are able to speak, the health-care provider will ask you questions about your symptoms, your medical history, and your medications. Answer as completely as you can. He or she will also examine you and observe you as you breathe.

If this is your first attack, or the first time you have sought medical attention for your symptoms, the health-care provider will ask questions and perform tests to search for and rule out other causes of the symptoms.

Measurements of how well you are breathing include the following:

• Spirometer: This device measures how much air you can exhale and how forcefully you can breathe out. The test may be done before and after you take inhaled medication. Spirometry is a good way to see how much your breathing is impaired during an attack.
• Peak flow meter: This is another way of measuring how forcefully you can breathe out during an attack.
• Oximetry: A painless probe, called a pulse oximeter, will be placed on your fingertip to measure the amount of oxygen in your bloodstream.

There is no blood test than can pinpoint the cause of asthma.

• Your blood may be checked for signs of an infection that might be contributing to this attack.
• In severe attacks, it may be necessary to sample blood from an artery to determine exactly how much oxygen and carbon dioxide are present in your body.

A chest x-ray may also be taken. This is mostly to rule out other conditions that can cause similar symptoms.

Asthma Treatment

Since asthma is a chronic disease, treatment goes on for a very long time. Some people have to stay on treatment for the rest of their lives. The best way to improve your condition and live your life on your terms is to learn all you can about your asthma and what you can do to make it better.

• Become a partner with your health-care provider and his or her support staff. Use the resources they can offer -- information, education, and expertise -- to help yourself.
• Become aware of your asthma triggers and do what you can to avoid them.
• Follow the treatment recommendations of your health-care provider. Understand your treatment. Know what each drug does and how it is used.
• See your health-care provider as scheduled.
• Report any changes or worsening of your symptoms promptly.
• Report any side effects you are having with your medications.

These are the goals of treatment:

• prevent ongoing and bothersome symptoms;
• prevent asthma attacks;
• prevent attacks severe enough to require a visit to your provider or an emergency department or hospitalization;
• carry on with normal activities;
• maintain normal or near-normal lung function; and
• have as few side effects of medication as possible.

Self-Care at Home

Current treatment regimens are designed to minimize discomfort, inconvenience, and the extent to which you have to limit your activities. If you follow your treatment plan closely, you should be able to avoid or reduce your visits to your health-care provider or the emergency department.

• Know your triggers and do what you can to avoid them.
• If you smoke, quit.
• Do not take cough medicine. These medicines do not help asthma and may cause unwanted side effects.
• Aspirin and nonsteroidal antiinflammatory drugs, such as ibuprofen, can cause asthma to worsen in certain individuals. These medications should not be taken without the advice of your health-care provider.
• Do not use nonprescription inhalers. These contain very short-acting drugs that may not last long enough to relieve an asthma attack and may cause unwanted side effects.
• Take only the medications your health-care provider has prescribed for your asthma. Take them as directed.
• Do not take any nonprescription preparations, herbs, or dietary supplements, even if they are completely "natural," without talking to your health-care provider first. Some of these may have unwanted side effects or interfere with your medications.
• If the medication is not working, do not take more than you have been directed to take. Overusing asthma medications can be dangerous.
• Be prepared to go on to the next step of your action plan if necessary.

If you think your medication is not working, let your health-care provider know right away.


Medical Treatment

If you are in the emergency room, treatment will be started while the evaluation is still going on.

• You may be given oxygen through a face mask or a tube that goes in your nose.
• You may be given aerosolized beta-agonist medications through a face mask or anebulizer, with or without an anticholinergicagent.
• Another method of providing inhaled beta-agonists is by using a metered dose inhaleror MDI. An MDI delivers a standard dose of medication per puff. MDIs are often used along with a "spacer" or holding chamber. A dose of six to eight puffs is sprayed into the spacer, which is then inhaled. The advantage of an MDI with a spacer is that it requires little or no assistance from therespiratory therapist.
• If you are already on steroid medications, or have recently stopped taking steroid medications, or if this appears to be a very severe attack, you may be given a dose of IV steroids.
• If you are taking a methylxanthine, such as theophylline or aminophylline, the blood level of this drug will be checked, and you may be given this medication through an IV.
• People who respond poorly to inhaled beta-agonists may be given an injection or IV dose of a beta-agonist such as terbutaline or epinephrine.
• You will be observed for at least several hours while your test results are obtained and evaluated. You will be monitored for signs of improvement or worsening.
• If you respond well to treatment, you will probably be released from the hospital. Be on the lookout over the next several hours for a return of symptoms. If symptoms should return or worsen, return to the emergency department right away.
• Your response will likely be monitored by a peak flow meter.

In certain circumstances, you may need to be admitted to the hospital. There you can be watched carefully and treated should your condition worsen. Conditions for hospitalization include the following:

• an attack that is very severe or does not respond well to treatment;
• poor lung function observed on spirometry;
• elevated carbon dioxide or low oxygen levels in your blood;
• a history of being admitted to the hospital or placed on a ventilator for your asthma attacks;
• other serious disease that may jeopardize your recovery; and
• other serious lung illnesses or injuries, such as pneumonia or pneumothorax(a "collapsed" lung).

If your asthma has just been diagnosed, you may be started on a regimen of medications and monitoring. You will be given two types of medications:

• Controller medications: These are for long-term control of persistent asthma. They help to reduce the inflammation in the lungs that underlies asthma attacks. You take these every day regardless of whether you are having symptoms or not.
• Rescue medications: These are for short-term control of asthma attacks. You take these only when you are having symptoms or are more likely to have anattack -- for example, when you have an infection in your respiratory tract.

Your treatment plan will also include other parts:

• awareness of your triggers and avoiding the triggers as much as possible;
• recommendations for coping with asthma in your daily life;
• regular follow-up visits to your health care provider; and
• use of a peak flow meter.

At your follow-up visits, your health-care provider will review how you have been doing.

• He or she will ask you about frequency and severity of attacks, use of rescue medications, and peak flow measurements.
• Lung function tests may be done to see how your lungs are responding to your treatment.
• This is a good time to discuss medication side effects or any problems you are having with your treatment.

The peak flow meter is a simple, inexpensive device that measures how forcefully you are able to exhale.

• Ask your health-care provider or an assistant to show you how to use the peak flow meter. He or she should watch you use it until you can do it correctly.
• Keep one in your home and use it regularly. Your health-care provider will make suggestions as to when you should measure your peak flow.
• Checking your peak flow is a good way to help you and your health-care provider assess what triggers your asthma and its severity.
• Check your peak flow regularly and keep a record of the results. Over time, your health-care provider may be able to use this record to determine appropriate medications, reducing dose or side effects.
• Peak flow measures fall just before an asthma attack. If you use your peak flow meter regularly, you may be able to predict when you are going to have an attack.
• It can also be used to check your response to rescue medications.

Together, you and your health-care provider will develop an action plan for you in case of asthma attack. The action plan will include the following:

• how to use the controller medication;
• how to use rescue medication in case of an attack;
• what to do if the rescue medication does not work right away;
• when to call the health-care provider; and
• when to go directly to the hospital emergency department.

Prevention

You need to know how to prevent or minimize future asthma attacks.

• If your asthma attacks are triggered by an allergic reaction, avoid your triggers as much as possible.
• Keep taking your asthma medications after you are discharged. This is extremely important. Although the symptoms of an acute asthma attack go away after appropriate treatment, asthma itself never goes away.