The Medical Consumer's Advocate

Ventilation Tube FAQ

Douglas Hoffman M.D., Ph.D.

Why does my child need ventilation tubes?

To understand what ventilation tubes accomplish, you first need to know a bit about ear anatomy. Here goes:

At the end of the external auditory canal (ear canal) is the eardrum, a thin, skin-lined membrane that vibrates in response to sound. Behind the eardrum is the middle ear. The middle ear is normally an air-filled space. The air in this space is constantly replenished via the Eustachian tube. The Eustachian tube is a muscular tube that connects the middle ear space with the throat. This is the tube you "pop" when you "pop your ears."

In some infants and children, the Eustachian tubes do not work very well. The tubes are closed most of the time in normal individuals, but in people with Eustachian tube dysfunction, the tubes open infrequently or not at all. This leads to inadequate ventilation of the middle ear space. The air that is trapped in the middle ear is gradually reabsorbed by the tissue lining this space. As the air is reabsorbed, the air pressure in the middle ear space decreases.

So: in children with Eustachian tube dysfunction, the air pressure is lower in the middle ear, relative to the "outside world." When the Eustachian tubes do manage to "pop," there is a suction effect, leading to throat secretions (saliva and nasal mucus, for example) being sucked up the tube into the middle ear. These secretions are laden with bacteria. Thus, children with Eustachian tube dysfunction tend to have frequent ear infections. In some cases, fluid may build up in the middle ear space. If the middle ear space is full of fluid (a condition known as effusion), the eardrum’s ability to vibrate in response to sound is seriously limited. This results in hearing loss.

Frequent ear infections and chronic effusions (effusions that last for more than 3 months) are the two main reasons that a child’s doctor may recommend placement of ventilation tubes. Both of these problems are related to Eustachian tube dysfunction.

 

How do the tubes work?

As the name would suggest, ventilation tubes allow air to pass into the middle ear space. They functionally replace the dysfunctional Eustachian tubes, inasmuch as they allow air to pass into the middle ear space.

Ventilation tubes are very small, about the size of a tomato seed. One popular style of tube is the bobbin, since it is shaped much like a sewing machine bobbin. Air passes freely through the hole in the center of the bobbin. As long as this hole remains unplugged (unblocked by wax, pus, blood, and so forth), the air pressure in the middle ear will always be the same as the air pressure in the ear canal.

 

Does my child really need these tubes?

There are always alternatives. Whether these alternatives are GOOD alternatives is quite another matter. There are two major alternatives to tube placement:

• No treatment. With time, most problems related to Eustachian tube dysfunction (frequent ear infections, chronic effusions) resolve. But how much time will this take? Unfortunately, it may take months, and sometimes years; indeed, a few unfortunate children grow up to become adults with Eustachian tube dysfunction.

• Medications to improve Eustachian tube function. Antibiotics, antihistamines, nasal steroid sprays and other anti-allergy medications are all used from time to time for this purpose. Ask your doctor whether these are worthwhile alternatives for your child.

 

What can I expect from surgery?

Your child will usually be given medication to decrease anxiety. The operation is performed under a general anesthetic (almost always, this involves anesthetic gas administered with a face mask, and not with a tube placed into the lungs.) The procedure takes about 5 minutes for each ear. Since it takes time to place your child under anesthesia, and additional time to wake up, the total time in the operating room is about 20 to 30 minutes.

Most infants and children wake up crying. This is probably not due to pain, but may instead be due to confusion or disorientation associated with the anesthetic.

Once your child has fully recovered from anesthesia, he/she will be discharged from the hospital. Chances are very good that your child will be "back to normal" a few hours after the operation. There is usually little pain associated with this operation; over the counter pain medications are generally sufficient. Discuss this with your doctor.

When tubes are placed to relieve chronic effusions, a child’s hearing will be much more acute afterwards. Although you might think this would be a good thing, some children find it very disturbing to discover that they live in a very noisy world! Don’t be surprised if your child complains that things are too loud.

 

What about getting water in the ears?

Until relatively recently, the dogmatic response to this question was, "NO! Keep the ears dry!!!" This may be unnecessarily strict, however. Under most circumstances, few precautions need be taken. Here are a few rules of thumb:

- Tap water (bath water, for example) and chlorinated water are relatively clean, and are much less likely to cause an infection than river or lake water, which are rife with bacteria.

- Water may cause an infection if it passes through the tube into the middle ear space. This is more likely to occur if the water enters the ear canal under pressure. Thus, if your child is a "dunker" in the bathtub (one who likes to dunk his/her head under the water), ear plugs are probably a good idea.

- If your child likes to swim, and certainly if he/she likes to dive into deep water, ear protection is a must. If water enters the ear canal under pressure, it can jet through the tube and injure the middle ear. This is painful, to say the least, and may cause permanent hearing loss.

My recommendation: discuss this issue with your doctor. Make sure you tell your doctor whether your child bathes or showers, does he/she practice "head dunking," and does he/she swim and/or dive.

 

What does the future hold?

Tubes last from 6 to 18 months. Like any other skin, the eardrum sheds dead cells. Very gradually, the tube works its way out of the eardrum. Tubes will often exit the ear unnoticed by parent or child. Occasionally, your doctor may need to remove an extruded tube; if the tube is just sitting in the ear canal, this removal is simple and painless.

For about 2 out of 3 children, a single set of ventilation tubes is all that is necessary– their ears are fine after the tubes fall out. If the child again develops effusions or recurrent infections, the same options are available (no treatment, medical treatment, or placement of ventilation tubes.) Additionally, ENTs will often recommend adenoidectomy for children who require a second set of ventilation tubes. There have been several excellent studies demonstrating the helpfulness of adenoidectomy in this clinical situation. Further discussion of adenoidectomy is beyond the scope of this information sheet.

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