thumb|300px|Infant undergoing bili light therapy in a United States maternity ward.
A bili light is a light therapy tool to treat newborn jaundice (hyperbilirubinemia). High levels of bilirubin can cause brain damage (kernicterus), leading to cerebral palsy, auditory neuropathy, gaze abnormalities and dental enamel hypoplasia. The therapy uses a blue light (420–470 nm) that converts bilirubin into an (E,Z)-isomer that can be excreted in the urine and feces. Soft goggles are put on the child to reduce eye damage from the high intensity light. The baby is kept naked or only wearing a diaper, and is turned over frequently to expose more of the skin.
Conventional bili lights shine from above the baby. A biliblanket consists of a fiber-optic blanket designed to transfer the light from a lamp unit all around the baby's body, and is more commonly used at home.
Neonatal jaundice
Jaundice (Hyperbilirubinemia) is common in newborn babies and presents itself as yellow discoloration of the skin and whites of the eyes (sclera). About 50 percent of term and 80 percent of preterm infants develop jaundice in the first week of life. This condition also causes babies to appear sick, experience difficulty waking up, make high-pitch cries, or not be able to be fed or gain weight. Bilirubin is an orange yellow bile pigment that is produced as a byproduct of hemoglobin as red blood cells break down (hemolysis). Bilirubin is then metabolized in the liver, recycled, and excreted in the bowel movements. When a baby has jaundice or hyperbilirubinemia, this can indicate that the baby's body is producing excess bilirubin or that the liver is too immature to be able to eliminate bilirubin fast enough. Most neonatal jaundice shows during the first week after birth. Nevertheless, when bilirubin levels become exceedingly high, the substance may move out of the blood, cross the blood brain barrier, and collect in brain tissue, damaging the baby's brain cells, a condition known as acute bilirubin encephalopathy. If acute bilirubin encephalopathy is not addressed promptly, Kernicterus syndrome can develop and cause permanent brain damage. In rare situations, a baby may experience seizures, deafness, cerebral palsy or mental retardation. The biliblanket releases waves of blue or white light, when these are absorbed in the skin, bilirubin breaks down and is eliminated from the baby's blood stream.
This lowers the yellowing effect in the baby's eyes and skin.
Side effects
One common side effect that is experienced by babies who are receiving phototherapy treatment is more frequent and loose stools. The color of these stools are usually a greenish color; however, this is normal because that is the way bilirubin is removed from the body. As bilirubin levels return to normal and phototherapy is no longer needed, the frequency of bowel movements and the color of the stools will return to normal. There is no statistical evidence that phototherapy causes melanoma.
Biliblanket
thumb|A baby being treated for jaundice with a BiliBlanket|268x268px
A biliblanket is a portable phototherapy device used to treat neonatal jaundice (hyperbilirubinemia). BiliBlanket is a trademark of General Electric's Datex-Ohmeda subsidiary, but its name has become the generic, colloquial term for a range of similar products and the term used in the medical professions. The name "biliblanket" combines the words bilirubin and blanket. The baby is placed in direct contact with the pad. Compared to standard forms of phototherapy, a biliblanket utilizes a fiberoptic system, allowing them to be used at home. The biliblanket system consists of three components: an illuminator, fiberoptic pad, and disposable pad cover. The fiberoptic pad is used to transport blue or white light from the light source, the illuminator, directly onto the baby's skin.
Proper use
The biliblanket setup consists of the light generator, termed the light box, the fibre-optic cable through which the light is carried, and the fiberoptic pad, which is a 25 cm x 13 cm (10" x 5") pad that is attached to the baby. The light generator stores the source of light, which is a halogen bulb. The fiber-optic cable connects the light generator to the fiberoptic pad, which contains fiberoptic fibers and usually has a disposable cover.
It is important to make sure that the light-source machine is placed on a flat, level, hard surface such as a table or nightstand to ensure proper ventilation. A disposable cover is placed onto the light pad and should be changed if the cover becomes soiled. For effective therapy, the baby's skin should be directly exposed to the light pad as much as possible. The light pad should be on at all times except during baths. The light pad is usually placed on the undressed baby's back with a diaper on. Clothing may be worn, but the clothing should be placed over the light pad, and the light pad should still be in direct contact with the baby's skin. The light pad should never be placed on the baby's head.
The biliblanket is safe and can be used for 24 hours a day as long as therapy is required. However, the duration of phototherapy will vary from individual to individual based on the baby's current condition and disease state. It will also depend on the physician's clinical judgement.
Blood tests may be required daily during phototherapy to assess the bilirubin levels and determine if normal levels have been reached and whether or not phototherapy can be stopped. Once the bilirubin levels are normal, the baby's skin will return to its normal color. Other advantages of the biliblanket are that it can be easily transported, can be used when the baby is sleeping, eating, and or being held, and promotes a relationship between parents and infants since they do not need to be separated during treatment.