The clinical application of transcutaneous bilirubinometry in full-term Chinese infants

The pattern of jaundice in Chinese full-term newborns has seldom been explored. This study was to 1) investigate the correlation between transcutaneous bilirubin indices (TcB) and serum bilirubin levels; 2) use TcB to follow the pattern of jaundice in Chinese full-term newborns; and 3) compare the sensitivity and specificity of TcB measured from the forehead (TcB1), and mid-sternum (TcB2) by receiver operating characteristic curves (ROC curves). From April 1 to August 31, 1989, a total of 3217 TcB were obtained from 305 inborn full-term newborns (male 175, female 130) during their first 6 days of life. The correlation between serum bilirubin levels and TcB measured from the forehead (TcB1) and from the mid-sternum (TcB2) was good (r = 0.82 and 0.86 respectively). For formula-fed infants, both TcB1 (16.3 +/- 3.0) and TcB2 (16.6 +/- 2.7) reached peak levels at 78-84 hours of age, while in mixed-fed infants, peak levels were noted at 54-60 and 84-90 hours for TcB1 (17.2 +/- 2.2) and TcB2 (16.6 +/- 2.6) respectively. The incidence of hyperbilirubinemia was 5.9 per cent. There were no differences in peak TcB levels between formula-fed and mixed-fed infants. The ROC curves suggested that TcB2 is better than TcB1 in sensitivity and specificity. It is concluded that TcB is a reliable device for monitoring jaundice in Chinese full-term newborns. Peak level of jaundice occurred at the third to fourth day of age. The incidence of hyperbilirubinemia in Chinese infants has decreased, for reasons which need further investigation.