It’s winter in the PICU and that means more respiratory illnesses, one of them being croup. This is an ancient illness — its very name comes from the Anglo-Saxon word to croak, which is what children with croup can sound like. The characteristic brassy cough sounds more like a seal to our modern ears, though. Also characteristic is a sound we call stridor, the sound of air rushing through a narrowed tube, in this case the child’s airway.

Croup is caused by viral infection of the region just below the vocal cords. One of several viruses can do it, but the usual offenders are members of the parainfluenza group. The infection causes swelling, and the swelling causes narrowing of the airway. This makes it more difficult for the child to breath — in some ways it is like breathing through a straw — and the child has to work harder to get air in. This can make the child’s chest cave in the wrong way with each breath, something called retractions. Fever, if present, is usually mild.

As with most viral illnesses, there is no specific treatment for croup — what treatment we have is directed at relieving the symptoms of throat pain and difficulty breathing. We do have several effective ways of doing this. Simple mist, as from a steamy bathroom, is a time-honored therapy to help a child breath. Inhaling a mist of the drug epinephrine shrinks the swollen tissues, although it only lasts for an hour or two. The drug dexamethasone, either orally or by injection, has become a standard therapy for moderately severe croup and it is quite effective. Acetaminophen or ibuprofen can treat fever and throat pain.

When should you bring your child to the doctor for croup? A good rule of thumb is if your child has stridor when sitting quietly or if there are any retractions present — both of these are indications for therapy with epinephrine or dexamethasone.

We always see a few children in the PICU with severe croup, usually those who need repeated doses of epinephrine or are working very hard to breath. On very rare occasions we need to use a breathing tube and a mechanical ventilator for these children. Nearly all children, however, recover from croup with no complications.

I’ve written a more detailed discussion of croup, which includes an x-ray of what it looks like and some uncommon causes of airway obstruction, in a Google Knol here.

Most people think medicine is a science. Medicine makes use of science, but it’s not science – it’s a mishmash of science, experience, intuition, guesswork, and blind luck. Many wish this were not so, but it is.

The last decade has seen an attempt to bring more scientific rigor into medical practice. The movement is called Evidence Based Medicine. The notion seems simple, one few could argue with: take a critical look at all the research that’s been done about a particular medical treatment and see if, on balance, the treatment works. The process has several important principles, among which are to establish in advance how much credance we should place on various research studies, especially when they conflict with one another. To do this we assign a hierarchy of reliability of the evidence. The weakest evidence is expert opinion alone — after all, experts can be wrong. The strongest evidence is the randomized, placebo-controlled trial.

These trials compare the results between two groups of patients: those who got the treatment and those who didn’t. One key to this is the placebo part: neither group knows until the trial is over who got the treatment and who got the “placebo,” the sugar pill. A second key is patients are randomly assigned to the treatment or the placebo groups. A final crucial element is that the doctors caring for the patients don’t know themselves who’s getting the treatment and who’s getting the placebo until after the trial is done. Then the investigators look at the data and see if the treatment works, if it’s better than the placebo.

Sounds simple. It isn’t, though, especially as it applies to the Holy Grail of evidence based medicine. For one thing, for some things there isn’t a good placebo — a major operation, for example. For another, physicians have only studied a tiny fraction of all medical conditions, typically those which affect a lot of people, are controversial for one reason or another, or which look financially promising to drug companies.

So how do I and my colleagues decide what to do? We use hard evidence if there is any. We do what makes sense in light of what we do know about the condition or others like it. We tend to do what we have been taught, and we respect the opinions of our medical forebearers. Sometimes we have no idea what to do, in which case it is usually better to do nothing. In short, we still rely to some extent on experience, intuition, guesswork, and blind luck. For myself, I actually like things to stay at least a little bit that way.

If you want to learn more about evidence based medicine, the guiding organization is the Cochrane Collaboration, a huge group of valiant volunteers who scour the medical literature to collect information about specific ailments and write reviews about what the data show. The Cochrane site is here.

This time of year I’m closely exposed to dozens of children with viral respiratory infections. I don’t want to get what they’ve got, both because it would be unpleasant for me and because my unhappy colleagues would be forced to cover whatever time away from the PICU an infection caused me. So I do whatever I can to stay well. This may sound like simple grandmotherly advice, but really the best way to keep from spreading respiratory viruses is to wash your hands a lot.

The reason is simple. Although viruses do fly through the air to some extent when coughed or sneezed, a more important way of spread is by touch. After infected persons blow their noses, for example, there inevitably is virus on their hands. The way to get rid of the virus? Wash those hands. Hospitals use a variety of special foams and gels for doctors and nurses to disinfect their hands as they go from patient to patient, and some of these are available in stores for you to buy, but plain soap and water is as good as anything.

You can read more about handwashing here, at the official web site of the Centers for Disease Control. The bulletin has some interesting historical observations about when doctors realized infections spread this way, and it is six years old itself. It still applies, though, especially during cold season.

Most polls show Americans put health care at the top of their concerns. All of the major presidential candidates have issued statements about what they would do to address these concerns, although the amount of detail each candidate offers varies quite a bit. The Kaiser Foundation has compiled a very useful side-by-side comparison of all the candidates’ positions on health care; you can read it here. These are links to what the candidates themselves (or their campaigns) have said they will do: Giuliani, Clinton, Romney, Obama, McCain, Edwards, and Huckabee.

Bob Laszewski, a keen observer of the issue, says that, on balance, the differences between the plans of the candidates from each party are relatively insignificant. The two parties, however, differ quite a bit from each other. From his analysis:

From “thirty thousand feet” all of the leading Republicans are offering much the same health care policy ideas — a more vibrant market serving a more responsible consumer who would control his health care choices in a system that doesn’t need to spend more money.

And, from that same “thirty thousand feet,” Democrats are all offering about the same thing — $100 billion+ in new annual spending to guarantee access for virtually all Americans to existing public and private health care plan options as well as some new ones created by the government.

I haven’t made up my mind yet whose ideas I most support on this issue. I have decided, though, that our current non-system is headed for an enormous crash and I want to see that crash headed off. Americans tend to postpone doing the things their individual health requires, such as exercise and diet, until they encounter a crisis; I don’t want the same thing to happen with our collective societal health.

The key thing is for all of us to think about this issue now. I hope these links will help you do that.