Children are extremely susceptible to respiratory infections.
From the nose and throat, air travels down the neck into the windpipe (the trachea). As it enters into the chest area, the trachea divides into two main tubes, the right and left bronchi.
Each bronchus carries air to the right and left lung, respectively. As the bronchus enters the lung, it divides into smaller and smaller bronchi, much the same as large branches of a tree divide into smaller branches and finally twigs. These smallest branches of the bronchi are called bronchioles.
At the end of bronchioles are the real working components of the lungs, small air sacs called alveoli. It is in these sacs where the oxygen breathed in passes into the bloodstream and the body's waste gas, carbon dioxide, passes out of the bloodstream.
Each segment of this system is subject to its own diseases. Starting at the top, the nose and throat, there is the common cold. Medically referred to as a URI (upper respiratory infection), it causes inflammation and swelling of the lining of the nose, throat, and sinuses.
Colds are caused by many types of viruses causing virtually the same symptoms. Colds go away by themselves and antibiotics are used only if there is a bacterial complication. Antibiotics only treat bacterial infections, not viral infections. For older children (over 6 years of age), zinc lozenges may be helpful in reducing the severity and duration of symptoms.
A little lower down the airway is the windpipe, which houses the vocal cords. If a virus attacks there, it may cause croup in children. This is characterized by a very deep, seal-like cough, and varying degrees of breathing difficulty primarily when inhaling. The vast majority of these cases are of a mild or moderate nature and need no treatment.
These episodes can be particularly frightening for parents because they most often occur in the middle of the night. Typically, the child (usually between the ages of 1-3) awakens with a “barking seal”-like cough and “stridor”. In stridor, the child appears of difficulty inhaling air which makes a “whistling sound” during inspiration.
Parents can help the child by either taking them outside into the cold air (properly wrapped) or going to a bathroom, closing the door and turning on hot shower, closing the drain, and letting “steam” fill the room. Both approaches should bring relief in about 5- 10 minutes. If the child does not gain relief, is drooling or complaining of throat pain, or appears to be struggling to breath, call your physician. He may need to be evaluated in the emergency room or in the physician’s office. Corticosteroids and racemic epinephrine can be used to treat this illness.
When an infection attacks the bronchial tubes, it is called bronchitis, with narrowing and swelling due to inflammation caused by the virus. Treatment for this condition can vary from none to the use of rather strong medications when the symptoms are severe.
Bronchodilators are drugs that loosen up these tight bronchiole tubes, allowing air to flow easier. Corticosteroids may also play a role by decreasing the swelling caused by the inflammatory process.
Somewhat similar to bronchitis is a condition that occurs primarily in infants called bronchiolitis, an inflammation of the smaller caliber tubes of the branching network of bronchi. It occurs in children up to age 2, with the peak incidence around 6 months of age.
In its typical presentation, an infant may appear to have a simple cold with a runny nose for a day or so. The condition then begins to worsen, with the child developing labored breathing as evidenced by an increased breathing rate and a pulling-in of the muscles between the ribs at each breath.
The child's cough becomes more frequent and dramatic. The child will often begin to wheeze, as evidenced by a high-pitched sound and more prolonged exhalation. The child's condition may remain this way for a few days and then improve or it may worsen and require hospitalization.
The disease is caused by several viruses, the most common one being the respiratory syncytial virus (RSV). Because of its viral nature, treatment is generally supportive in nature.
Prevention of Complications from RSV
Infants and children who are less than 24 months with chronic lung disease or severe congenital heart disease should received humanized monoclonal antibody (Paliviziumab). Similarly, infants less than one year of age who were born less than 28 weeks gestation and who are less than six months of age and who were born 29-32 weeks gestation should also receive this preventive therapy. Injections begin before the respiratory disease season continues during the winter. Talk to your physician early in the Fall to ensure your child qualifies and the medication is ordered.
The respiratory disease that causes the most anxiety in parents is pneumonia. This is caused by an infection in the air sacs, the alveoli, at the end of the small bronchioles. These sacs become filled with fluid, often of a thick purulent nature, which interferes with proper exchange of carbon dioxide. Concerning signs for pneumonia include rapid breathing even in the absence of fever, cough in infancy (less than 1 year of age), and very ill appearance (“floppy” baby, lack of responsiveness like smiling, poor skin color and/or pronounced loss of appetite). If you are concerned, consult your physician immediately.
The severity of the pneumonia will depend on the amount of lung tissue involved. Fortunately, in the majority of children, pneumonia is not very serious and can be easily treated at home. Antibiotics are required for bacterial pneumonia. Sometimes, if the pneumonia is severe or if the child is very young, hospitalization is required.