Clinical Evaluation of a New Device for Transcutaneous Bilirubin Measurement in Japanese Infants

Background: The advantages of using noninvasive techniques of bilirubin measurement are the avoidance of pain and of local infection as well as real-time results. Recently the accurate measurement of total serum bilirubin by transcutaneous bilirubin using a reflectance spectrophotometer, the BiliCheck^TM, has been introduced in a heterogeneous newborn population. But there is limited data on the use of BiliCheck^TM on Oriental babies including Japanese newborn infants. <br>Methods: A total of 240 transcutaneous bilirubin measurements were taken from the three body sites (forehead, chest, and left or right upper arm) of 52 Japanese neonates and compared with simultaneous total serum bilirubin measurements determined by the direct spectrophotometric method. Of 240 occasions, 206 measurements were taken before starting phototherapy and 34 were during phototherapy. A phototherapy eye-patch was placed over the measurement site on the forehead prior to the start of phototherapy. <br>Results:As a preliminary study, total serum bilirubin concentrations measured by the direct spectrophotometric method and by the bilirubin oxidase method were compared. There was a good correlation between the values obtained by these 2 methods (r=0.980, y=1.05 x＋0.176, p <0.0001). The precision of the device was expressed as a mean coefficient of variation of less than 5% and operator difference was small as coefficient of variation below 5%. Before phototherapy, the correlations between the transcutaneous bilirubin measurements by the BiliCheck^TM and total serum bilirubin by the direct spectrophorometric method were high; r=0.925 on forehead, 0.848 on chest and 0.822 on upper arm, respectively. However, the correlation became less during phototherapy (on forehead r=0.803, p<0.001). <br>Conclusion: These data indicate that accurate measurements of total serum bilirubin by transcutaneous bilirubinometry with BiliCheck^TM are applicable in Japanese infants. But the use of the device for infants who receive phototherapy needs further study.