Croup

by Warren P. Silberstein, M.D.
04/07/97

Croup is generally cause by an upper respiratory virus infection, but, although children with croup may have some cold symptoms including fever and runny nose, the illness is very different from a cold. The virus causes inflammation around the trachea (windpipe), larynx (voice box), and sometimes the bronchial tree. The medical term for croup is laryngotracheobronchitis. The inflammation around the trachea and larynx causes the cough to sound so brassy. The irritation that causes the unusual sounding cough is the inflammation in the airway rather than mucus. As a result, cough medicines are not very helpful to control croup symptoms. In some cases the cough is so extreme it hurts to cough. If the inflammation in the airway is severe enough it causes swelling of the tissues with narrowing of the airway. As a croupy child breathes through these narrowed airways it makes noise. This noise is called stridor. The more tissue swelling there is, the narrower the airway becomes and the more difficult and noisy it becomes for the child to breathe.

Fortunately, most children who have croup never have more than a croupy cough. The illness generally runs its course in 3 to 5 days. Antibiotics are not helpful for treating croup because viruses don't respond to antibiotics. The only treatments that are useful for croup are those that relieve symptoms.

Mild croup can generally be managed at home. Croup responds very well to moist air, so it is useful to keep a vaporizer or a cool mist humidifier by the bedside. These are available at most pharmacies and many discount department stores. This should not be confused with an ultrasonic room humidifier which should never be placed at the bedside. If you use a steam vaporizer be sure not to leave it unattended with a toddler walking around since it makes steam by boiling water. A steam vaporizer could cause a scalding burn if pulled over onto a child.

If your child awakens with croup even with a vaporizer going, to get even more concentrated moisture into the air, turn on your hot shower and fill the bathroom with steam. Then bring your child into the bathroom and have him breathe the steam for 10 minutes. You should stay with your child the whole time since a small infant may become overwhelmed by the steam and you need to observe your child to be sure that his breathing difficulty doesn't require urgent medical care.

When a child has noisy breathing it is useful to determine if the child is wheezing or has stridor (the sound of croup). Stridor differs from wheezing because it is caused by upper airway obstruction whereas wheezing is caused by obstruction of the lower airways (the bronchial tree). The noise of stridor occurs primarily as a child breathes in and is a harsh, crowing noise. Wheezing occurs primarily as the air comes out and is a softer, higher pitched noise, somewhat like a cat's meow. Stridor may respond to steam. Wheezing does not respond to steam. If you have a child who wheezes you may have medication at home to treat the wheezing. Stridor does not respond to medications for wheezing. Any time a child has difficulty breathing, no matter what the cause, unless you know exactly what it is and how to treat it and have the means to treat it at home, it requires urgent emergency medical attention. Call your doctor or go straight to the emergency room for difficulty breathing.

As frightening as a severe croup attack can be, doctors have very effective treatments for croup in the emergency room. Inhalation of Vaponefrin (racemic epinephrine) usually reduces the swelling of the tissue so dramatically that even the severely croupy child may be symptom free after just one inhalation. Unfortunately, Vaponefrin does not have the long duration of action that inhaled asthma medicines have, and there may be rebound (increased severity of symptoms) after the Vaponefrin wears off, so children who need Vaponefrin inhalation usually require hospital admission over night for observation and additional treatment as necessary.

If your child has a bad night with croup, but not severe enough to require medical attention during the night, his symptoms may be almost gone by morning. Sometimes a croupy child may have no daytime symptoms. Even if your child is symptom free by morning, if he had any labored breathing overnight you should see your doctor during the day. Since the croup may be more extreme at night your doctor may wish to treat your child with a short course of steroids to reduce the inflammation in the airways in order to avoid middle of the night breathing difficulty.

There are a few variations on croup. Some children tend to get croupy whenever they have colds; however they don't generally have extreme symptoms. Spasmodic croup usually results from spasm around the trachea caused by allergies or viral infection. These children also don't usually have severe symptoms. Spasmodic croup may often improve from cold air so that the patient gets better on the way to the doctor! It happens, so don't be embarrassed. Your doctor should understand.

Some textbooks classify epiglottitis as a form of croup. The epiglottis is the cover for the trachea. When it becomes inflamed it can obstruct the opening of the airway. Epiglottitis is generally caused by a bacterium called Hemophilus influenza B. Children with epiglottitis are generally extremely ill with high fever. Their difficulty breathing is so extreme that they are unable to lie down and they usually lean forward slightly. They also are unable to swallow so they drool. The obstruction of the airway may result in stridor (noise) similar to croup, but a barky cough is not typically part of the picture. Fortunately, epiglottitis is a rare disease which has become even more rare since we routinely immunize children against Hemophilus influenza B.

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