It was a rewarding experience to see Mrs. L. in the nursery after she had given birth to her third child. The new baby boy was born by a repeat C-section. Mom and baby were doing just fine. Also in the room were dad and their two other children, ages nine and eleven years. I examined the baby with the family present and baby brother got a clean bill of health. Mrs. L. said, “It’s really all coming back to me now…it has been a number of years…but I am suppose to make an appointment to see you with the baby in around two weeks, right?”
I explained to her that until a few years ago that would have been exactly correct. But recently the American Academy of Pediatrics has recommended that all babies going home within a few days should be examined for jaundice within 48 hours. She seemed surprised but conceded. “I am sure that you have to err on the safe side. But none of my other children had jaundice, so I doubt that it will be a problem.”
Mrs. L. went home on a Monday and made a follow-up appointment for Wednesday afternoon. The 11-year-old came along. Mrs. L. kiddingly stated, “Well, we’re here. But I’m just not exactly sure why.” Mom was doing a successful job with the breast feeding as the baby’s weight was fine. Then we undressed the baby.
With the proper lighting and lying on the white examining paper instead of the yellow swaddling blanket it was clearly obvious that the baby was jaundiced. Even mom did a double take. “Oh my gosh,” she muttered out loud. “I didn’t pick up on this at home.” Then mom asked a series of logical questions in rapid fire. “What am I doing wrong? Why is he the only one of my children to get jaundiced? Is it because I’m older than when I had my other children? And, more importantly, what is jaundice, really?”
Jaundice is the yellow discoloration of skin that newborns get in the first few days of life. While jaundice can be associated with serious infections and conditions, the most common cause by far in a healthy newborn is physiologic jaundice during the newborn period. It is caused by a pigment called bilirubin, a by-product of the breakdown of red blood cells.
A full term baby is born with an overabundance of red blood cells, RBC’s. Shortly after birth many of these RBC’s are taken to the liver to be broken down and processed. Normally the bilirubin is conjugated, or hooked up with protein, which prepares it to be excreted. Once the bilirubin is conjugated it can be excreted through the digestive tract (that is what makes our stool brown), or the urinary tract (that is what makes the urine yellow).
In many newborns, their immature liver is overwhelmed by the large amount of bilirubin and it can’t process it fast enough. As a result some of the bilirubin spills back into the bloodstream. The increased level of bilirubin is what gives the skin a yellow appearance. In the majority of cases, after a few days the liver really gets going and clears out all of the excess bilirubin. The jaundice resolves on its own.
There is no predicting which child will or will not become jaundiced. Normal physiologic jaundice of the newborn usually becomes obvious by the second or third day of life. It can then rise and peak by the fifth or sixth day, and then resolve over another few days. This is true in MOST cases. However, there are exceptions.
We can measure the exact amount of bilirubin that is in the bloodstream. One can look at a baby and detect some jaundice when the bilirubin level is above 4. Jaundice starts in the face, spreads to the chest, down the abdomen, down the extremities and lastly to the hands and feet. When the white of the eyes becomes yellow the bilirubin is around 8. When it has spread to the extremities, the bilirubin is most likely in the teens. By the time it has spread to the hands and feet it is probably in the high teens.
The critical level for bilirubin in a term, healthy newborn is 20. The goal should be to keep the bilirubin level below 20. At levels over this the bilirubin can get into the brain and cause permanent brain damage. The number 20 was arbitrarily picked to insure that no baby is missed, falls through the cracks or is not identified until it is too late. It is worth mentioning that the original studies done to arrive at this number of 20 involved tiny and sick premature infants. No one really knows if this is truly such a critical number in a healthy term newborn. But no one is willing to take the chance to find out. So, as of now, the goal is to keep the bilirubin below 20 in ALL cases.
The answer to Mrs. L.’s first question is that she has done absolutely nothing wrong. The fact that her other children did not have jaundice has no bearing whatsoever on her new baby. It is purely an individual case whether or not a baby will get jaundice. Age should not have anything to do with it as long as the breast feeding is coming along well.
One of the best ways to enhance the elimination of the bilirubin from the body is to insure good stool and urine output. Stimulating the gut to work helps the liver to process and excrete the excess bilirubin much quicker. A jaundiced baby who is breastfeeding may benefit from some supplemental fluids until mom’s breast milk comes in fully. In Mrs. L.'s case, however, the baby was feeding well and demonstrated good weight gain. I was confident that he did not need to be supplemented.
The baby’s bilirubin level was 16.4. We would need to measure it again tomorrow since we had only one value and could not predict whether it would go up or down. We discussed optimizing his fluid intake.
Then mom asked me a frequently asked question. “Should I put him near a window?” This would not be of any real benefit. It is a common myth that seems to be promulgated from generation -to-generation, but is worthy of an explanation. If the conditions are right jaundice can be treated with phototherapy. This is done by putting the baby in an isolette, wearing nothing but eye patches, and exposing him to a bank of fluorescent lights. In essence, the bilirubin in the skin absorbs the light energy and is converted to an isomer of itself. This can be excreted via the liver without having to be conjugated. It is a safe and non-invasive way to treat jaundice. The fallacy of putting the baby in the windowsill is that the baby is bundled up and fully dressed. Therefore, only the mid-face is exposed to the sunlight and, as such, is not very effective or practical.
Mom seemed pleased with that answer and said, “If someone were to have asked me about jaundice before this visit I would have expounded like an expert on the subject, not really knowing what I didn’t know about the matter. I’ve learned more about jaundice in the past 15 minutes than I could ever have hoped to learn from my family, friends, or internet over the next few weeks. We discussed his feeding regimen for the next 24 hours and planned to check another bilirubin the next morning.
I called Mrs. L. as soon as I got the repeat level which was 12.2. The jaundice had peaked and was coming down nicely. There was no reason to check another bilirubin unless his jaundice took a turn for the worse. We were DONE!
This article is meant to deal with uncomplicated and garden variety of normal physiologic jaundice of the newborn. There are a number of medical situations and conditions that can predispose to exaggerated jaundice. These, however, are far beyond the intent of this article.