Prediction of neonatal hyperbilirubinemia by transcutaneous bilirubin nomograms / 中华围产医学杂志

ABSTRACT

Objective To predict the risk of neonatal hyperbilirubinemia by transcutaneous bilirubin (TcB) nomograms and clinical risk factors.Methods Healthy term and late-preterm newborns (≥ 35 gestational weeks,and birth weight ≥ 2 000 g) born in Guizhou Maternal and Child Care Hospital between January 1,2013 and December 31,2013,were included.TcB levels were continuously recorded within 168 hours after birth.The value of hour-specific TcB nomogram combined with receiver operating characteristic (ROC)curves and Logistic regression model for predicting risk of hyperbilirubinemia was evaluated.Pearson's Chisquare test was also used for statistical analysis.Results A total of 5 250 cases were enrolled.TcB increased rapidly in the first 40 hours after birth,slowly increased between 40 to 96 hours,and reached a high level after 96 hours.Among them,the 95th percentile TcB stablized at 96 hours after birth.The 40th,75th and 95th percentile TcB peak levels were 173,217 and 248 μmol/L.Among the 5 250 neonates,there were 277 cases (5.3％) in the high-risk zone within 72 hours.The positive predictive value (PPV) was 22.02％;1 087 cases (20.7％) and 1 854 cases (35.3％) were in the medium-high risk and medium-low risk zones along with the PPV of 10.58％and 3.72％,respectively.There were 2 032 cases (38.7％) in the low-risk zone with the PPV of 1.38％.Multivariate analysis showed that the TcB high-risk zone after 72 hours was associated with gestational age,delivery mode,feeding mode and TcB level of risk zones within 72 hours.Compared to those born at ≥ 40 gestational weeks,those born at ≥ 37-＜40 gestational weeks were more likely in the TcB high-risk zone after 72 hours (OR=1.80,95％CI1.29-2.51).The likelihood was reduced by 42％ among neonates born with cesarean section compared to those delivered vaginally in term of the TcB high-risk zone after 72 hours.Infants who received mixed feeding were less likely to be in the TcB high-risk zone after 72 hours when compared to breastfed infants (OR=0.51,95％CI0.29-0.88).With the reduction of the high-risk zone level within 72 hours,the likelihood in the TcB high-risk zone after 72 hours was also decreased.ROC curve showed that the area under the curve (AUC) for predicting hyperbilirubinemia was 0.75 and its 95％CI was 0.72-0.78,with a sensitivity of 90.00％ and specificity of 40.00％.The AUC of a combination of predictive results obtained by the Logistic regression model with significant variables in univariate analysis and high-risk zone after 72 hours was 0.66,and its 95％CI was 0.62-0.69.AUC estimated by Logistic regression model according to the TcB levels of risk zones within 72 hours combining with clinical risk factors was 0.79,and its 95％CI was 0.76-0.82 (P＜0.01).Conclusions Hour-specific TcB nomograms of newborns in our hospital have been obtained,which facilitates the prediction and early intervention of neonatal hyperbilirubinemia.