And while I’ve mentioned the level of the bilirubin, notice that it’s in the context of the gestational and the chronological age of the baby and the timing of the jaundice (and by my addition) how well the baby is transferring breastmilk. 

I had this fabulously scarring episode when I was a very tired resident in which I mentioned that a child’s white blood cell count was 13.5 (yes, I still remember that number).  My attending stopped me, wrote 13.5 on a piece of paper and threw it into the air.  When it landed at my feet, he said “Jenny, what’s that?”  I dutifully replied “It’s this child’s white blood cell count.”  He then uttered words that have stuck with me forever.  “No, it’s a random number flying through the air.”

In short, the level of bilirubin can’t be interpreted without knowing more about the baby.

Let’s try a case.  (I wrote this one for the AAP Breastfeeding Curriculum) 

This  3-day-old exclusively breastfed girl, born at term after an induced vaginal delivery. The baby nursed well in the delivery room within an hour after delivery and has been skin-to-skin with mom. She has been feeding every 3 hours since. The baby’s last stool, about 18 hours ago, was black and tarry. The baby and mother have the same blood type. A bedside transcutaneous bilirubin

measurement at 24 hours of age places the baby in the “high intermediate” range.

Mother’s concerns:

• Her nipples are cracked and bleeding

• Her breasts are soft and it doesn’t seem as though her milk has “come in” yet

• The baby has lost weight

• The baby does not seems as alert as she was the day before

What factors may be contributing to the baby’s hyperbilirubinemia?

Healthy breastfed infants normally have increased, non-pathologic, elevations in serum bilirubin, sometimes called "breastmilk jaundice." Breastmilk jaundice can last for weeks, and is thought to be beneficial to the infants because bilirubin is an antioxidant.

This is important because, as I mentioned above, newborns do not have other sources of antioxidants.[1]

Breastmilk jaundice needs to be distinguished from "starvation jaundice" which may indicate a pathologic condition. One of these conditions is decreased caloric intake and in our case, this caloric deprivation is likely secondary to a breastfeeding problem.

This baby girl is likely to have starvation jaundice because of poor milk transfer. Nipple trauma is caused by a poor latch. If the baby is latched incorrectly, she cannot transfer milk and will not get the calories need to facilitate the excretion of bilirubin. Another indication of poor milk transfer is the presence of black, tarry meconium stool at day of life 3. Colostrum, the first milk made for the baby, is a laxative promotes the excretion of meconium.  In general, meconium should be well past dark and tarry by this point.  The weight loss is another article for me to write.  (And PS.  I really dislike the term “milk coming in.”  It’s been there all along.  Just a different recipe!!!)

What does it mean to be in the “high intermediate” range?

The American Academy of Pediatrics recommends performing an assessment of every infant for the risk of severe hyperbilirubinemia. [2]Transcutaneous bilirubin levels are a way to estimate the serum bilirubin level. Once obtained, that level is plotted on a nomogram (sometimes referred to as the "Bhutani curve") according to the baby's age in hours. That nomogram is divided into  to risk levels. " High Intermediate" risk means that the babyhas a high intermediate risk of subsequent bilirubin level exceeding the 95th percentile of bilirubin levels.[3]  It means the baby has a high intermediate risk of the bilirubin getting higher.  What the magic number where danger occurs is not known.

The goal of these measurement and subsequent graph plotting is to prevent kernicterus, a totally preventable, devastating neurologic disease.  Nothing about this cheking levels and graph plotting involves “assessing a feeding.”  We should work on getting that in there.  

While this screening can identify babies at risk for severe hyperbilirubinemia, it does not predict the risk of kernicterus or other complications of severe hyperbilirubinemia. Again,  the "curve" does not predict the risk of kernicterus.  It predicts who is at risk for the bilirubin getting higher. No screening test  currently exists that will reliably identify all infants at risk of developing kernicterus. [2]Most children are not at risk for the development of kernicterus and not all children with kernicterus have a  history of hyperbilirubinemia. [1, 2] (Makes you wonder why we screen... sorry, soap box)

What do we do next?

Since the cause of the baby's jaundice is likely "starvation jaundice," we need to increase the baby's caloric intake. We need to feed the baby.  We need to evaluate the latch or enlist the help of someone, such as lactation consultant, who can help this mother breastfeed without pain. If the baby would  need to be supplemented, our first choice is her mother's expressed breast milk, so we need to supply her with a pump and show her how to appropriately use it.