Childhood Asthma

by Food and Drug Administration (FDA)

As a child, author John Updike, like many other children, had the snuffles in the winter and hay fever in warm weather. It wasn't until years later as an adult, however, that Updike's asthma was diagnosed during a physical exam. Noting Updike's spread rib cage, or barrel chest — the sign of the chronic asthmatic — and the characteristic wheezing sounds heard through the stethoscope, a doctor correctly identified his condition.

While some children eventually "outgrow" asthma as the size of their breathing tubes increases, Updike's disease grew worse in maturity. He describes an acute episode that occurred on a visit to his parents' farm in Pennsylvania on a summer day, at the height of the pollen season, in the company of a dog and cats, and surrounded by dust, mold, and plants and trees in full bloom:

An asthma attack feels like two walls drawn closer and closer, until they are pressed together. Your back begins to hurt, between the shoulder blades, and you hunch. I could not stand up straight and looked down at the flourishing grass between the sandstones. I thought, This is the last thing I'll see. This is death. The breathless blackness within me was overlaying the visual world, this patch of my mother's grass, with a thin gray film, and the space between the two walls I was struggling to pry apart felt hardly wide enough for a razor blade. My children and parents had come out on the back porch to watch me, and a rictus twitched my face as I thought how comic this performance must look, this wrestle with invisible demons. . . . I felt immensely angry at my own body and at everybody. Like a child blind in his tantrum I thought, Serve them right, and waited to die, standing bent over and gasping, of suffocation. (Copyright 1989 by John Updike. Reprinted with permission of Alfred A. Knopf from Self-Consciousness.)

Updike didn't die. After a quick visit to the hospital emergency room and two injections of adrenalin, he experienced that "opening of the bronchial tree which is to asthmatics an interior sunrise, a rebirth into the normal world."

Such scenes are played out in emergency rooms throughout the United States, most of the time with a similar euphoric ending. But sometimes not. In 1988, according to statistics from the National Institutes of Health, 4,580 Americans died from asthma, some of them children. Though asthma can come on with such suddenness and severity that medical help is not available in time, doctors believe that most asthma deaths are preventable.

Common Childhood Disease

Asthma is the most common chronic childhood disease. It causes more hospital admissions and visits to the emergency room and is responsible for more school absenteeism than any other chronic disease in childhood.

Estimates of the number of children under 17 with asthma vary from 3 million to 8 million, but Nancy Sander, founder of the national organization Mothers of Asthmatics, Inc., believes the incidence is much higher than the statistics show. Says Sander: "Asthma is often misdiagnosed as acute infectious bronchitis [inflammation of the bronchi] or bronchiolitis [infectious inflammation of the bronchioles] — viral diseases — or recurrent pneumonia."

Though asthma can occur at any age, about 80 percent of the children who will develop asthma do so before starting school. The common "trigger" is a viral upper respiratory infection.

Childhood asthma appears to be increasing worldwide. In American children 3 to 17 years old, asthma's prevalence rose 50 percent in the 1980s, according to the National Center for Health Statistics, and the death rate for children under 14 doubled from 1977 to 1983. Health professionals don't know why asthma is on the rise, but they think that air pollution or other environmental changes may be implicated.

What Is Asthma?

Asthma is a bronchial disease in which the airways are so sensitive that they sometimes become blocked, making breathing difficult. Of the many factors involved in this airway hypersensitivity problem, the one most experts are sure about is heredity. With the appropriate triggers or stimuli (see accompanying article), people who have inherited a susceptibility to asthma may develop the disease. People without this potential don't get asthma. Though many people with asthma have allergies, all allergic people are not asthmatic.

The airways primarily affected are the bronchi, the two main branches of the trachea (or windpipe), and their smaller extensions, the bronchioles. Wrapped around the bronchial tubes are bundles of muscles that control the size of the air channel. When bronchial muscles tighten up, the air channels narrow; when they are relaxed, air channels are of normal size. Contraction and relaxation of these muscles are completely involuntary.

The bronchi are lined with a mucus membrane that is a continuation of the lining of the nose, mouth and throat. Glands embedded in the bronchial wall produce secretions (mucus) that keep the inner surfaces of the bronchial tubes moist.

In asthma, the bronchial tubes, mucus membranes, and mucus glands react abnormally to stimuli. Bronchial muscles clamp down around the bronchial tubes, causing a condition known as broncho-spasm. The mucus membranes inside the tubes become inflamed and swollen, further narrowing the air channels. The bronchial glands start producing large amounts of a particularly thick and sticky mucus that is hard to cough up and often forms plugs that further obstruct airflow. As a result of these changes, not enough oxygen can get into the body, and air loaded with carbon dioxide is trapped inside the lungs' air sacs. Asthmatics have to fight to exhale.

Forcing air out through clogged, narrowed airways causes vibrations of the bronchi and the mucus trapped inside the bronchi, resulting in high-pitched whistling sounds, or low- pitched rumbles or rattles, all known as wheezing. Sometimes wheezing is clearly audible; other times it is difficult to hear without a stethoscope.

Coughing is another important symptom, especially in very young children. Scratching the neck or chest or yawning a great deal should alert concerned parents that an attack is on the way. Shortness of breath, spitting up mucus, a pale, sweaty face, and a tight chest are other symptoms. When the attack is severe, wheezing sometimes disappears because the smaller airways are completely blocked, a dangerous stage. Other signs of trouble are fast breathing (hyperventilation), a hyperinflated chest due to trapped air, and an exhalation time twice as long as the inhalation time.

An asthma episode can last for hours or days, occur once in a lifetime, or every day. It can be mild, or so severe that the child requires hospitalization to treat respiratory failure. Though asthma can strike at any time, attacks often begin during the night. Asthma is an intermittent, reversible illness.

About the Author

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