A comparison of transcutaneous bilirubinometers: SpectRx BiliCheck versus Minolta AirShields

Abstract

Background: Two devices are available for making transcutaneous estimates of serum bilirubin (SBR): the Minolta AirShields JM102 and the new SpectRx BiliCheck.

Objectives: (a) To measure how well the readings produced by these devices agree with SBR measured in the laboratory; (b) to estimate for each device, the proportion of infants with clinical jaundice who would require blood sampling if the device was used as a screening tool to detect infants with SBR > or = 250 micromol/l.

Design: Prospective cohort study of jaundiced infants who required SBR at < or = 20 days of postnatal age. Those who had received phototherapy or exchange transfusion were excluded.

Setting: Tertiary neonatal service in South-East Scotland.

Interventions: Within 30 minutes of SBR sampling, transcutaneous bilirubinometry was performed using one Minolta and two SpectRx devices (designated A and B).

Results: Sixty-four neonates were enrolled, 19 of which were preterm (31-35 weeks). The 95% confidence intervals of a device reading corresponding to SBR were +/- 66.7, +/- 67.9, and +/- 66.4 micromol/l respectively. Using the devices to identify all SBR > or = 250 micromol/l would reduce SBR sampling by 23%, 16%, and 20% respectively.

Conclusions: Given that SBR levels range from 50 to 400 micromol/l in jaundiced infants, the 95% confidence intervals of the devices are wide at +/- 67 micromol/l. The SpectRx can be used as a screening tool for hyperbilirubinaemia but there is no advantage in using it over the Minolta.

Figure 1

Bland-Altman plots for the Minolta device. The dotted line represents 95% confidence intervals of the difference, ± 66.7 µmol/l. SBR, Serum bilirubin; TcB, transcutaneous bilirubinometry.

Figure 2

Bland-Altman plots for the SpectRx A device. The dotted line represents 95% confidence intervals of the difference, ± 67.9 µmol/l. SBR, Serum bilirubin; TcB, transcutaneous bilirubinometry.

Figure 3

Bland-Altman plots for the SpectRx B device. The dotted line represents 95% confidence intervals of the difference, ± 66.4 µmol/l. SBR, Serum bilirubin; TcB, transcutaneous bilirubinometry.