40 - The Cephalocaudal Progression of Dermal Icterus in Preterm Infants

Publication Number: 2037.40

Amrryn Halari, Rutgers, Robert Wood Johnson Medical School, New Brunswick, NJ, United States; Thomas Hegyi, Rutgers, Robert Wood Johnson Medical School, New Brunswick, NJ, United States; david G. McMurray, Rutgers, Robert Wood Johnson Medical School, union, NJ, United States

Background: Visual recognition of jaundice and its progression has been used for managing neonatal hyperbilirubinemia.

Objective: To document the cephaloprogression (CCP) rate of TcB indices obtained from various body areas and assess whether total serum bilirubin levels (TSB) influenced this effect.

Design/Methods: TcB indices were collected from the forehead (TcB-F), chest (TcB-C), abdomen (TcB-A), knee (TcB-K), and foot (TcB-f) of premature infants at the same time as a TSB measurement. Ratios comparing TcB indices from different sites to the forehead were calculated (for example, R1 = TcB-C/TcB-F) and compared. The CCP rate was calculated using a least-squares method and examined in relation to postnatal age and TSB levels. Finally, the CCP rate was analyzed for its ability to predict a Delta value, which was defined as the difference between the phototherapy threshold and TcB-F level.

Results: Sixteen preterm infants (BW 2033±301 g, GA 33.6±1.2 weeks) were examined 90 times during their first week of life. TSB correlated with all TcB levels, and site TcB indices correlated with each other. TcB-F showed a significant correlation with Delta at r = 0.790. R1 was 1.06±0.28, R2 0.96±0.36, R3 0.75±0.45, and R4 0.47±0.35. Each R value was significantly different from the one cephalad; significant correlations remained. The overall CCP slope was -4.17 ± 2.23, unaffected by postnatal age or TSB. The CCP slope correlated with the Delta value at a correlation coefficient of r = 0.421. As the slope became more negative, the Delta value approached zero. Seven samples obtained under phototherapy showed significantly higher TSB, R2, R3, and R4 ratios, along with a lower slope.

Conclusion(s): CCP of dermal bilirubin occurs in premature infants, with TSB levels correlating with TcB indices obtained from most sites at approximately r = 0.6. The decline in TcB, as measured by the CCP rate, was unaffected by postnatal age or TSB. Phototherapy influenced the progression but did not affect the CCP rate’s ability to predict the Delta level.