The issue of food allergies is a complex one, probably because the food we eat is complex stuff. Many parents observe that particular foods don’t agree with their child. Pain, bloating, and diarrhea are all symptoms that can be evidence of this. Often such parents will say that their child is “allergic” to a particular food that they see causing those sorts of symptoms.

A broader term for this is food intolerance, the observation that particular foods upset the child’s digestive system. There are many examples of this kind of thing. One of the most common is a deficiency along the intestinal wall lining of lactase, the enzyme that digests the sugar lactose. This is not an allergy — it means that the person is intolerant of lactose, the sugar in many milk products. This lactase deficiency may be inherited or acquired later. (You can read more about this problem here.)

To a physician, the word “allergy” has a very specific meaning: it means that parts of the child’s immune system are reacting to components of the food. A common offender is peanuts (about 1% of all children), but there are many others. The symptoms of these true allergies can be much more severe, and typically cause problems outside the digestive system. Hives and difficulty breathing, either from wheezing or from swelling in the throat, are not uncommon. We occasionally see children in the PICU who have these more severe reactions to food. Parents of such children often need to have an injectable medication, epinephrine, handy at all times if this happens.

How common are food allergies and intolerance? A recent study in the journal Pediatrics gives us some answers. The authors found that in 2007, 4% of children under 18 had some form of problem with food. This was an increase of 18% over the previous decade, although it was unclear if this was a real increase or simply reflected increased awareness among parents and physicians. This particular survey, although broad, did not distinguish between allergy and intolerance. However, the authors noted that it correlated with other, smaller studies in which true allergy was documented with specific tests. So it seems like a real phenomenon

Here is a recent article of mine published by Smartman Daily.

Most dads with a toddler have experienced the ear drum game. For the minority who haven’t, it goes something like this. Your child has a cold for a few days, but otherwise seems fine. Suddenly she spikes a high fever and clearly hurts somewhere. You take her to the doctor. He takes a very quick look–only seconds, it seems–at her ears and pronounces that she has an ear infection. By the age of three, eighty percent of all children will have had one, and half will have had more than one. Here are answers to six important questions about this common condition.

#1: How can a doctor be sure your child has one?
Here’s a trade secret–frequently we aren’t. If you ask five pediatricians to look in a child’s ear, you may well get five different opinions. This is why medical students call it the ear drum game–it seems whatever they say about a child’s ear, their instructor will say the opposite. Sometimes the diagnosis is obvious. The ear drum is inflamed and bulges outward from the pressure behind it. That pressure comes from infected fluid clogging up the normally air-filled middle ear cavity. Those are the easy ones. The tougher ones are ear drums that are somewhat red, a bit distorted in their shape, perhaps a little less mobile than usual. In those children doctors are often swayed by other things–fever, if the child seems to be pulling at her ears, if she has had past ear infections. These cases are judgment calls, but doctors often follow our old saying that “common things are common,” so we tend toward diagnosing ear infection if it is a borderline case.

#2: Where do ear infections come from?
The middle ear, the place where sound waves bouncing off the ear drum get passed along to the brain so a child can hear, is normally free of germs. There is a tube connecting the middle ear to the back of the nose, there to let air in and out. You can feel this happening when your ears pop going up and down in an airplane. The nose is normally thick with germs. The connecting tube has ways of keeping the germs out of the middle ear, but when those defenses break down the germs pounce on the opportunity, crawl up the tube, and cause an ear infection. The most common cause of tube malfunction is a viral respiratory infection, which is why an ear infection so frequently follows a cold. The tendency for the tube to malfunction also runs in families, which is why frequent ear infections do the same.

#3: Why do we treat ear infections with antibiotics?
An ear infection means germs in the middle ear, but often a child’s body can handle the germs without help. After all, children have been getting ear infections for eons and antibiotics have only been around for a half-century or so. Sometimes these germs aren’t even bacteria, so antibiotics would be of no use anyway. The practice among most American physicians over the past decades has been to treat all ear infections with antibiotics. The reason was to reduce the chances of a child getting one of the uncommon complications that can happen, and the number of these complications has dropped significantly in the antibiotic era.

#4: Okay, but do ear infections always need antibiotics?
For children over six months, the answer is no. The antibiotics-for-all approach has always been questioned by some doctors, especially for children older than two. These doctors reserve antibiotics for children whose symptoms last more than a day or so. This is a decision that should involve parents. Most want antibiotics, and there is nothing wrong with that–it is standard practice. But if you don’t want them, at least right away, another acceptable approach is to get a prescription for the antibiotic, but not fill it unless your child’s symptoms persist. More and more physicians and families are opting for this. Antibiotics are not risk-free. Either way, it’s a good idea to treat the ear pain and fever with medicines like ibuprofen (Motrin) or acetaminophen (Tylenol).

#5: What about prevention?
We know some things are associated with ear infections, and they share the property of contributing to malfunction of the tube between the middle ear and the nose. Exposure to tobacco smoke is one, because it irritates the lining of the nose. Another is putting a child to bed with a bottle, because every time a child swallows the tube opens wider. If the child is lying on her back, the nose bacteria have an easier time of reaching the middle ear.
Sometimes doctors prescribe a low dose of a daily antibiotic for a child who has had many infections. The more controversial kind of prevention is placing a plastic tube through the ear drum to connect the middle ear directly with the outside world. These so-called pressure equalization tubes work by helping keep the middle ear free of the fluid that gives bacteria a hospitable place to grow. If your child has a lot of ear infections, your doctor may recommend these. Besides talking to your doctor, you can learn more about the generally accepted reasons for placing tubes at several authoritative sites, such as here.

#6: Why do ear infections generally go away when a child gets older?
By the time a child gets to school-age, ear infections are uncommon. This is because, as the skull grows, the connecting tube gets longer and less straight, putting a useful mechanical obstacle in the way of germs trying to get up the tube to reach the ear. Additionally, older children get fewer colds than toddlers. So, if your child has a lot of ear troubles, take heart in the fact things will certainly get better over time.

Often children in the PICU need a mechanical ventilator — a breathing machine — so parents are confronted with this machine. When do we use them and how do they work?

There are three main reasons for using a ventilator: 1.) the child’s lungs are not working well, not getting needed oxygen into the body and carbon dioxide waste out (severe pneumonia is a good example); 2.) the child is not awake and aware enough to breathe and cough properly on his own (a head injury is an example); 3.) the child’s lungs and level of awareness are fine, but he is too weak to breath properly (various muscle problems are examples).

There are many different kinds of ventilators made by different companies, and superficially they may look very different from one another. They have an array of dials and flashing indicators on them, and most draw complicated graphs on a screen as the ventilator works. But in spite of this variability, at root all common ventilators are alike (there are exceptions — special machines we use in special situations). They give a child a breath of air down through a breathing tube, called an endotracheal tube, which we place through a child’s mouth or nose. That air nearly always has extra oxygen in it. We express this additional oxygen as a percent — ordinary room air is 21% oxygen (most of the rest is nitrogen) and pure oxygen is 100%.

We use all the knobs on the machine to set what kind of breaths we want — how big and how often. We also tell the machine what to do if the child takes a breath on her own, usually telling it to help the child in one of several ways with her spontaneous breathing attempts. Finally, we tell the machine what to do between breaths, typically to maintain some air pressure in the system (called PEEP, for positive end-expiratory pressure).

The whole point of using a ventilator is to take over the job of breathing from the child. The machine can do it all, or it can assist the child while she does some of the work. A mechanical ventilator is not an all or nothing device. After the child has healed and no longer needs the ventilator, we can progressively turn down the settings on the machine, in this way asking the child to take over her own breathing more and more. When she can do all the work herself, we pull out the breathing tube.

These principles are straightforward. But if your child, or one you know, needs a ventilator machine, you should know that managing a ventilator is a fine art — it can’t be done by cookbook. We have general guidelines we follow, but most pediatric intensivists have their own personal wrinkles in how they apply the guidelines, using what has worked for them over the years. Most importantly, each child is different and reacts to the ventilator differently, so its use needs to be tailored to each child.

Mechanical ventilators in the PICU are an excellent example of something that appears, on the surface, to be high-tech modern medicine in action. Using one successfully, though, takes some low-tech skills of the sort good physicians have used for generations.