Why Are Some Babies Treated With Bili Lights?

Baby under bili lights.
Skin Problems Image Gallery Bili lights help newborns recover from jaundice. See more skin problem pictures.
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If you've ever been in the neonatal unit of a hospital, you may have seen babies wearing tiny eye shields under blue lights. It almost looks like the babies are in some kind of weird blue tanning bed. Those blue beams are called bili lights, and they help prevent newborns from getting brain damage or other complications from a condition known as newborn jaundice.

Newborn jaundice, or hyperbilirubinemia, occurs when a newborn's liver isn't quite up to the task of breaking down red blood cells for excretion. The resulting buildup of the byproduct bilirubin in the body's tissues turns the infant's eyes and skin yellowish. Left untreated, the condition can lead to cerebral palsy, brain damage or hearing loss. Some amount of jaundice is expected in newborns, since the infant's liver has to take over the job of breaking down bilirubin for the first time -- the placenta and the mother's liver do the work before birth. If the jaundice lasts too long, is accompanied by other factors, or if the baby has risk factors such as being born prematurely, then treatment is necessary [source: National Institutes of Health].


Bili lights are a form of phototherapy. The lights -- which can be fluorescent or LED -- produce light between 420 and 470 nanometer wavelengths [source: Rice University]. (This is where the blue color comes from.) The light passes through the infant's skin and breaks down the bilirubin into a form that the baby can eliminate. It's important for the light to make contact with as much of the infant's skin as possible, so infants undergoing this treatment aren't wrapped in blankets, and nurses turn the infants regularly to expose different areas of the body.

Throughout the treatment, hospital staff monitors the infant's temperature and other vital signs. They also keep tabs on bilirubin levels via blood tests. The most common risk associated with bili light therapy is dehydration, so babies sometimes get fluids intravenously. The eye shields simply protect the infant's eyes from irritation due to the bright lights.

Treatment with bili lights usually takes 24 to 48 hours to complete, at which point the newborn's liver can handle the bilirubin itself. If the bili lights don't work, a blood exchange transfusion can be used, in which the infant's blood is slowly drained and replaced with donor blood or plasma.

Bili lights aren't usually used to treat jaundice in adults. In newborns, jaundice is typically a temporary condition, so the bili lights just need to do their job until the infant's liver functions kick in. In adults, jaundice is caused by some underlying condition, usually a liver problem or a blocked duct. Therefore, treating adult jaundice requires diagnosing and treating the root cause.

For more information on newborns and blood conditions, see the links on the next page.



Babies Bili Lights FAQ

How long do babies stay under bili lights?
Treatment with bili lights usually takes 24 to 48 hours to complete, at which point the baby's liver can handle the bilirubin itself.
How can I treat my baby's jaundice at home?
Many doctors and midwives recommend placing the baby (or sitting while holding them) in indirect light by a well-lit window for 10-15 minutes four times a day. However, it's best to speak to your own health care practitioners to determine the best way to treat your child's mild jaundice.
What kind of light breaks down bilirubin?
Bili lights are a form of phototherapy and are blue in color. They can be fluorescent or LED, and produce light between 420 and 470 nanometer wavelengths.
Why do they put babies under a blue light?
Special blue lights — or bili lights — are used in cases where a newborn's liver needs help breaking down red blood cells for excretion, known as bilirubin. They ultimately help prevent newborns from getting brain damage, cerebral palsy, hearing loss, and other complications from a condition known as jaundice.
Is phototherapy painful for baby?
Phototherapy is safe, effective, and not painful or uncomfortable for your baby. Though it's commonly done in hospital, sometimes your child can undergo treatment at home. You can inquire at your hospital to determine whether this is possible.
How can I calm my baby while they're under bili lights?
Some newborns have trouble settling under the lights, so consider pulling up a chair and stroking and talking to your baby. You can also inquire with the hospital whether they have a bili blanket available, which will allow you to hold your child while they're wrapped up in the blanket and in your arms or on your chest.

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  • Williams, Mike. "Kitchen serves up blue-light special." Rice University, April 30, 2009. (April 30, 2010)http://www.media.rice.edu/media/NewsBot.asp?MODE=VIEW&ID=12513
  • Medline Plus. "Newborn Jaundice." National Institutes of Health. (April 29, 2010) http://www.nlm.nih.gov/medlineplus/ency/article/001559.htm