The influence of the reserve albumin concentration and pH on the cephalocaudal progression of jaundice in newborns.

The relationship between cephalocaudal progression of jaundice and bilirubin concentration, reserve albumin concentration and plasma pH was studied in 47 newborn infants. Furthermore, the cephalocaudal progression of the yellow colour of the skin was measured in 131 newborns at birth and on the third postnatal day. The cephalocaudal colour difference correlated positively to the bilirubin concentration (P much less than 0.001), to the reciprocal of the reserve albumin concentration (P less than 0.05) and to the squared hydrogen ion concentration (P = 0.04). The cephalocaudal colour gradient at birth correlated positively to the gradient at the third postnatal day (P less than 0.0004). The results support the hypothesis that the cephalocaudal progression of jaundice in icteric newborn infants may be explained by conformational changes in the young bilirubin-albumin complex.