Transcutaneous bilirubinometry decreases the need for serum bilirubin measurements and saves money.

Abstract

Except for routine screening for inborn errors of metabolism, the most frequent laboratory test performed in the well infant nursery is a serum bilirubin measurement. The Minolta/Airshields jaundice meter provides an objective measurement of the degree of newborn jaundice and is useful for identifying which infants require a serum bilirubin measurement.1,2 This instrument has been studied extensively and performs well as a screening device.1,2 We hypothesized that the routine use of the jaundice meter in our nursery would reduce both the need for serum bilirubin measurements and costs. We deliver more than 5000 infants annually, 80% of whom are cared for by private pediatricians. We first established the relationship between serum bilirubin levels and the transcutaneous bilirubinometry (TcB) index in 356 white newborn infants born at 36 weeks' gestation or later. All serum bilirubin determinations were performed in the clinical laboratories by direct spectrophotometry (Bilirubinometer; Advanced Instruments, Needham Heights, MA; or Paramax, Irvine, CA). Physicians ordered serum bilirubin levels on clinical indication, and directly after blood was drawn, a TcB measurement was obtained by nursery nurses from the lower end of the sternum. During this phase of the study, the TcB measurement was not provided to physicians. Ten TcB determinations on each of three infants yielded coefficients of variation of 0%, 3.6%, and 5.2%. The instrument's calibration was checked daily against the glass standards provided by the manufacturer. Once introduced for clinical use, TcB measurements were compared every 3 months with 10 bilirubin determinations to ensure consistency with the data previously obtained. The jaundice meter was introduced for routine clinical use on November 1, 1990. For the guidance of pediatricians, tables were posted in the nursery showing the relationship between the TcB index …