1261 TRANSCUTANEOUS BILIRUBINOMETRY IN INFANTS; INFLUENCE OF RACE AND PHOTOTHERAPY

Abstract

The transcutaneous bilirubin meter, TcBM, a non-invasive spectral device developed by Yamanouchi (with Minolta Co.) gives an objective index of cutaneous bilirubin. We have compared TcBM indices with total serum bilirubin (A.O. Bilirubinometer) in 29 white and 142 black infants and evaluated the influence of race and phototherapy. Correlation between TcBM and total bilirubin was strong in both black (r=0.79) and white (r=0.87) infants. TcBM indices in black infants were higher than in white infants at serum bilirubin levels less than 5mg/dl; this difference disappeared at bilirubins greater than 10mg/dl. At TcBM indices less than 13, serum bilirubins in all infants were less than 5mg/dl. TcBM indices greater than 20 were associated with serum bilirubin levels greater than 7mg/dl. In white infants receiving phototherapy, the correlation between TcBM indices and total serum bilirubin decreased but remained good (r=0.79); in black infants there was no longer a strong correlation (r=0.36). This discrepancy appears to be due to the tanning effect of phototherapy. In sum, in the absence of phototherapy this device is useful in screening both black and white infants for significant degrees of bilirubinemia. TcBM indices below 13 may preclude the necessity for an invasive bilirubin determination; indices above 20 suggest a need for such a procedure. This simple device avoids the pitfall of subjectivity inherent in any visual appraisal of icterus (including the Gosset Icterometer).