What Is a Bili Light?

A bili light is a tool used in phototherapy to treat newborns for jaundice, a medical condition also known as hyperbilirubinemia. The equipment produces a specific type of blue light. When a jaundiced newborn's skin is exposed to this light, the light waves break down the body's excess bilirubin so it can be removed by the body's waste systems.

Bilirubin is a natural byproduct of the body's effort to reuse red blood cells. In excessive amounts, it causes jaundice, a common but dangerous condition typified by a yellow tinge to the skin and whites of the eyes. Jaundice tends to show up in newborn babies within a few days of birth, and hospitals typically are equipped with stations outfitted with bili lights to treat the condition.

During pregnancy, the mother’s liver breaks down red blood cells for the baby, so it is not uncommon for a newborn baby’s liver to be unable to perform this job on its own just after birth. The result is that bilirubin begins building up in the body, leading to jaundice, which usually causes the baby to have a yellow shade to both his skin and the whites of his eyes. When parents see these symptoms, they are advised to get immediate medical treatment, because high levels of bilirubin can lead to brain damage, cerebral palsy or hearing issues.

A bili light relies on the concept of phototherapy, and it is largely made up of either fluorescent or light-emitting diode (LED) blue lights. The point of blue light therapy is that the wavelengths can pass through the skin of the baby and into the liver, helping it break down the red blood cells in the body. This can make it easy for the baby to eliminate these cells through urine and stools, rather than allowing the byproduct bilirubin to collect in the body. In most cases, exposure to a bili light is only required for a day or two, though other options may be explored if phototherapy does not work within that time frame.

Babies typically have to wear small protective glasses while under a bili light to keep their eyes from being damaged by bright lights. Newborns being treated for jaundice usually wear only a diaper under a bili light, and nurses frequently have to turn them over to ensure that the whole body is treated. During this time, doctors monitor vital signs, temperature and reactions to the phototherapy. They also usually give fluids through a vein to reduce the chance of dehydration when using a bili light.