Can We Use a Transcutaneous Bilirubin Reading After Phototherapy?

Discussion Unconjugated hyperbilirubinemia in the newborn is a normal occurence. After birth the infant must rely on its own relatively immature liver to detoxify metabolites, the infant’s gastrointestinal tract also is not yet working as well for excretion, the infant is usually slightly fluid deficient before breastfeeding and/or bottle feeding are well established, and there is increased breakdown of red blood cells as the fetus has a higher hemoglobin than an infant and thus an infant is relatively hemoconcentrated. The total bilirubin rises from 1.5 mg/dL to 6.5 mg/dL (+ or -2.5 mg/dL) over the first 3-4 days of life. A differential diagnosis of neonatal unconjugated hyperbilirubinemia can be found here. A differential diagnosis of conjugated hyperbilirubinemia can be found here. Phototherapy uses the skin to change the bilirubin to the more water-soluble lumirubin by using blue light at wavelengths of 420-480 nm. In doing so it causes blanching of the skin which obviously will change TcB levels. Factors which influence correlation between transcutaneous bilirubin (TcB) and total serum bilirubin (TsB) include skin color, TcB measurement body location, TsB level, the specific make and model of TcB bilirubinometer and if phototherapy has been used. Most professional guidelines currently advise against using TcB for determining hyperbilirubin level after phototherapy because of limited data that is available to determine the accuracy and clinical validity after photo...
Source: PediatricEducation.org - Category: Pediatrics Authors: Tags: Uncategorized Source Type: news