[Transcutaneous bilirubin determination in the newborn infant. Recommendations of the Swiss Neonatology Group].

The clinical usefulness of transcutaneous bilirubinometry with the Minolta-Air Shield bilirubinometer was evaluated at four obstetrical neonatology units (Basle, Berne, Lucerne and Zurich). Transcutaneous bilirubin (TcB), expressed as bilirubin index, was compared with simultaneous serum bilirubin estimations in healthy Caucasians babies born at term with a birth weight of more than 2500 g. TcB measured over the forehead: 926 determinations in 629 newborns. TcB measured over the sternum: 404 estimations in 260 newborns. TcB estimations over the sternum produced a closer correlation (r = 0.93) with serum bilirubin than estimations over the forehead (r = 0.81). Mean serum bilirubin value as well as the corresponding 5th and 95th percentiles were calculated for each TcB index. From the data obtained the following practical conclusions can be drawn: TcB estimations are reliable for giving the indication to perform serum bilirubin determinations. In patients with risk factors for kernikterus serum bilirubin should be determined at a TcB index of greater than or equal to 18, in babies without risk factors at a TcB index of greater than or equal to 21.