Every day that I work in the lab, I usually end up drawing blood from a newborn or a child under 10 years old. The children are pretty easy if they are over 1 year old, since you only have to hold them down screaming and finish it fast. If you work quickly and confidently, the parents can handle it pretty well. Of course, I realized today that now when I see children ages 1-10, I feel guilty/apologetic because I am used to thinking that I am about to inflict pain upon them and see that terrified, betrayed look in their eyes. I'm talking about when I am not even in the laboratory - just seeing a cute five-year old girl in an elevator makes me feel bad because I "know" that in a couple seconds those curious, happy little eyes will change. I'm pretty desensitized in the lab, but out of the lab when I attempt to look at a child happily, I feel like I am a wolf in sheep's clothing.
At any rate, I also draw blood from newborns. 95% of the time, the purpose for the blood draw is that it is a bili baby. A bili baby is a newborn with elevated levels of bilirubin (hyperbilirubinemia). The most obvious symptoms are jaundice, or yellowing of the skin and the whites of the eyes. Prolonged exposure to such high levels of bilirubin can cause brain damage, hearing loss, eye muscle problems, physical abnormalities, liver damage, and death. There are two reasons a baby may have hyperbilirubinemia. One is increased destruction of blood cells, usually caused by antibodies from the mother if the baby and mother have different blood types. The other is accumulation of bilirubin because the newborn's system is not excreting as much as it produces - primarily because the liver is immature and unable to process the bilirubin. For this reason, preterm babies are more likely to suffer hyperbilirubinemia: their liver is not as developed.
Treatment for hyperbilirubinemia is phototherapy. Light is absorbed through the skin and helps convert the excess bilirubin into a more excretable form for the infant. In extreme cases, blood transfusions are necessary. For babies under 7 days old, the average acceptable level of bilirubin in the blood is 10 mg/dL, 6 mg/dL for babies less than 24 hours old.