Jaundice (hyperbilirubinemia) occurs in approximately 60% of full-term babies and nearly 80% of premature babies. A baby with jaundice will have a yellow skin tone by the third or fourth day postpartum. This yellowing occurs when the bilirubin level in the blood is elevated. When hemoglobin breaks down, the end product is bilirubin. Because newborns need an elevated level of hemoglobin in utero, yet not after birth, their bodies must work to metabolize the excess bilirubin given off by the breakdown of hemoglobin. The key organ in this function is the liver. The liver is responsible for converting the fat-soluble bilirubin to water-soluble bilirubin in order for the excess to be excreted through bile or urine. Unfortunately, often a newborn's liver is not yet developed enough to handle this workload. When all the bilirubin is unable to be excreted, the remaining is absorbed and the circulatory system carries the excess to all the body tissues causing the yellowing of the skin.
There is normal physiologic jaundice, as indicated above, which is simply caused by an immature liver. If jaundice occurs within 24 hours of birth, it may be pathologic in nature and a result of Rh or ABO incompatibilities. Other causes of jaundice are prematurity, infection, hemorrhage, too much acid in the body, and certain medications given to mom. One to two percent of breastfed babies develop breast milk jaundice from a substance in the mother's milk that interferes with the bilirubin metabolism. This type usually appears a few weeks after the birth.
Physiologic jaundice and breast milk jaundice may require no treatment. Simply waiting, watching is often the request. Some newborns will have blood tests done daily to make sure the bilirubin level doesn't get too high. With breast milk jaundice, especially at higher levels, temporary interruption of breast feeding may be suggested. Typically a newborn requiring treatment will undergo phototherapy (exposure to light) as the preferred treatment. The newborn will be placed under fluorescent lights for approximately 48-72 hours. Some hospitals have fiberoptic phototherapy blankets which enable the baby to be held and fed while benefiting from the phototherapy. Phototherapy causes the fat-soluble bilirubin to convert to water-soluble for elimination through feces or urine. Some side effects of phototherapy are dehydration, skin rash, lethargy, and tanning. In severe cases of jaundice, newborns may require an exchange transfusion of blood.
Treatment is essential with elevated bilirubin of 13mg/dL or greater to avoid kernicterus. Kernicterus is jaundice of the brain tissue. When serum bilirubin levels of 20mg/dL and above are reached, brain damage is likely. The survival rate for newborns with kernicterus is 30%. Of the 30% that survive, the newborns usually develop cerebral palsy, mental retardation, or serious sensory disabilities.
Bobak, IM, and Jenson, MD. Maternity & Gynecologic Care: The Nurse and the Family. St. Louis: Mosby, 1993.
Phillips, CR. Family-Centered Maternity/Newborn Care. St. Louis: Mosby, 1991.