Noninvasive determination of neonatal hyperbilirubinemia: standardization for variation in skin color.

The estimation of plasma bilirubin concentration in neonates, using a transcutaneous, noninvasive jaundice meter, is significantly affected by many factors, such as gestational age, birthweight, phototherapy, and skin pigmentation. In an attempt to minimize the influence of skin color and hence circumvent the need for standardization curves for different ethnic populations, we obtained noninvasive jaundice meter readings from the infant's midsternum within 4 hours of birth and subtracted this measurement from subsequent reading in infants with hyperbilirubinemia. These results were correlated with simultaneous plasma bilirubin determinations. By this method, a single standardization curve and improved sensitivity, specificity, and predictive values for the noninvasive determination of neonatal hyperbilirubinemia in a population of mixed ethnic origin was obtained.