Bahr et al reported an hour-specific nomogram for serum total bilirubin for neonates >= 35 weeks of gestation. The authors are from the University of Utah, Intermountain Health, Stanford University and Lucille Packard Children's Hospital in Stanford.
Patient selection: neonate >= 35 weeks of gestation
Parameters:
(1) number of hours since birth
(2) serum total bilirubin in mg/dL
The nomogram consists of a plot of hours versus total bilirubin, divided by 3 lines - low, middle high. This defines 4 zones:
(1) low risk
(2) low to intermediate risk
(3) intermediate to high risk
(4) high risk
lower line =
= (-0.0005941 * ((hours)^2)) + (0.1537 * (hours)) + 2.542
middle line =
= (-0.0006407 * ((hours)^2)) + (0.1876 * (hours)) + 3.114
upper line, from 0 to 24 hours =
= (0.008017 * ((hours)^2)) - (0.1018 * (hours)) + 6.7
upper line from 25 to 144 hours =
= (-0.0009022 * ((hours)^2)) + (0.2458 * (hours)) + 3.648
