Transcutaneous bilirubinometry: Its role in the assessment of neonatal jaundice

Objective: To review the literature on transcutaneous bilirubinometry so that its exact role in the prevention of kernicterus or bilirubin encephalopathy could be determined. Design and Methods: Literature searches were done in Medline and Current Contents. Results: It is estimated that about 50% of newborns have an episode of jaundice in the first few days of life. Six percent of newborns may develop hyperbilirubinemia (> 220 mu mol/L), which can potentially cause bilirubin encephalopathy or kernicterus, a severe neonatal disease. In the past, serum bilirubin (SE) has been the preferred method of detecting hyperbilirubinemia in newborns. The ordering of SE in neonates is based on visual evaluation by either physicians or nursing staff. Skin puncture collection of blood exposes the neonate to trauma and risk of infection. A noninvasive device for predicting serum bilirubin levels in newborns diminishes the need to do skin punctures. One such device that has been very extensively studied is the Minolta AirShields Jaundice Meter.(TM) It is a portable lightweight instrument that uses reflectance measurements on the skin to determine the amount of yellow color present in the skin, namely transcutaneous bilirubin (TcB). Although the TcB measurements correlate well with serum bilirubin (SE) levels, they cannot accurately predict serum bilirubin because of error related to a variety of factors. Conclusions: TcB cannot be used directly to make decisions about transfusions or phototherapy in neonates. It is a good tool for screening neonates to determine when a laboratory measurement of serum bilirubin is needed. Such a practice requires careful selection of the decision level so that false-negative TcB values do not prevent appropriate serum bilirubin tests from being done. Copyright (C) 1997 The Canadian Society of Clinical Chemists.