Last week I got a frantic call from a friend who had just delivered a "healthy baby". Over the past couple of days she had noticed that the tips of the fingers and toes had a bluish discoloration. I asked her to see her pediatrician the next morning and if he heard a heart murmur to request for a echocardiography to rule out a heart defect.

1% of all children born anywhere in the world may have a congenital heart defect or are born with a heart abnormality. The reasons are multiple and include a host of reasons ranging from genetics to maternal dietary deficits. Parents should investigate a bluish color they spot on their baby's skin. Blue skin means the underlying blood has a blue cast, rather than the nice pink color of blood with lots of oxygen in it. Fortunately, in most cases it's quite normal and harmless.

What's the Underlying Problem When the Skin is Blue?

There are two reasons why the blood under the skin might look blue:

> The baby's lungs are not getting enough oxygen. Since oxygen is what makes blood turn red, blood cells without oxygen remain blue ("cyanosis").

> The underlying blood is moving sluggishly, so the normal veins underneath that carry blue, oxygen-poor blood back to the heart are more noticeable.

You can tell if there is insufficient oxygen in the blood by checking the color of the skin all over your baby's body. If there is a bluish cast everywhere (especially in areas with a lot of blood flow, like the lips, tongue, and vagina or scrotum), this could mean all of the blood is blue and there could be a problem with the heart or lungs.

More commonly, it's only certain areas -- like the hands, feet, or area around the mouth -- that look blue some of the time. This is usually perfectly normal and just reflects the baby's somewhat immature circulation.

Tips for Concerned Parents:

If you are concerned about a blue tinge to your baby's skin, check his entire body. An off-and-on blue cast to the hands and feet, with pink skin elsewhere, is not a sign of a problem, but rather just a little bit of immaturity to the circulatory system, which will go away over time. It is important to see your pediatrician if this is persistent. Fortunately we can diagnose most of these defects by a simple noninvasive ultrasound by a cardiologist. It is also important to note that most of these defects can be corrected by surgery which is available in some heart hospitals.

When to Worry:

If there is a bluish cast over the entire body, the blood may be lacking sufficient oxygen. This is very worrisome and you should seek medical attention immediately.

But you don't need to worry if your baby's hands and feet turn blue for a short period of time when the rest of the body is pink. This is merely your baby's immature circulatory system at work.

And by the way, my friend's baby is doing just fine!

(Dr Amit Varma is Chief Operating Officer and Director Critical Care Medicine at Fortis Flt Lt Rajan Dhall Hospital in Delhi)