Transcutaneous bilirubin (TcB) measurement is a way to find out how much bilirubin is in your child’s blood without using a needle. Bilirubin is a substance that is made each day as red blood cells break down.
Normally the liver removes bilirubin from the blood, but a newborn baby’s liver doesn’t do this well right after birth. When there is a lot of bilirubin in the blood, the skin and whites of the eyes get yellow. The yellow color of the skin and eyes is called jaundice. This test may be done to check bilirubin levels if your child has jaundice.
Usually no preparation is needed for this test.
Your healthcare provider will put a meter on your child’s head or chest. The meter will send a quick flash of light through the skin to measure the bilirubin level.
Bilirubin levels normally vary with age. Your healthcare provider will assess you child’s bilirubin level based on how old your child is, how close your child was to his or her due date when born, and other factors.
Your child’s level of bilirubin may be higher than normal because:
If the bilirubin is low, your child many not need any more tests. If it’s high, your child may have a blood test to confirm the results. (The transcutaneous bilirubin measurement is easier and quicker to do than a blood test, but it’s not as accurate.)
Test results are only one part of a larger picture that takes into account your child’s medical history, physical exam, and current health. Sometimes a test needs to be repeated to check the first result. Talk to your child’s healthcare provider about the test result and ask questions, such as: