Bilirubin nomogram for prediction of significant hyperbilirubinemia in North Indian neonates

Gestational Age-Specific Nomogram of Transcutaneous Bilirubin in First 120 h of Life for Term and Late Preterm Indian Neonates

OBJECTIVE

To create a nomogram based on transcutaneous bilirubin values (TCB) in first week of life for term and late preterm (>34 weeks) neonates.

METHODS AND DESIGN

Prospective longitudinal study.

SETTING

Four tertiary-care teaching hospitals (one each in eastern and southern India, two in northern India) between February 2019 and March 2020.

PARTICIPANTS

A total of 2492 term and late preterm (>34 weeks) neonates.

INTERVENTION

Bilirubin was measured by transcutaneous bilirubinometer (Drager JM-105, Germany) in all neonates in pre-specified times of the day, 12 hourly every day since birth till discharge between 48 and 72 h, and data were recorded in epochs of 6 hourly intervals. Post-discharge, all neonates were called for review in next 48 h.

OUTCOME MEASURES

Primary-TCB in first week of life. Secondary-factors having significant association with significant hyperbilirubinaemia requiring phototherapy.

RESULTS

Total of 2492 neonates (males 1303 and female 1189), with a total of 14 162 TCB recordings were analysed and mean hourly bilirubin (TCB) at hourly intervals till 120 h and then daily bilirubin values on Days 6 and 7 were tabulated. We have constructed hour-specific bilirubin nomogram with percentiles as per gestational age in term and near-term Indian neonates till 120 h of life. Amongst the known risk factors, delayed cord clamping, primipara and breastfeeding jaundice had significant association for hyperbilirubinaemia needing phototherapy.

CONCLUSIONS

We have created gestation-specific nomogram of TCB levels in 6 hourly intervals for the first 120 postnatal hours, obtained from a large predominantly breast fed healthy, term and near-term Indian neonates.

Applicability of the hour of life approach in hyperbilirubinemia among Filipino term infants

BACKGROUND

Hyperbilirubinemia remains a common morbidity among infants. Additional research on bilirubin kinetics and associated risk factors will contribute to providing a more targeted management approach for the Filipino infant.

OBJECTIVE

To develop a Filipino bilirubin nomogram by studying bilirubin patterns during the first 5 days of life.

METHODOLOGY

This prospective study recruited 1,412 stable, full-term infants (≥37 weeks age of gestation) born at the Philippine General Hospital (PGH). Using the Dräger-Minolta JM-103 jaundice meter, transcutaneous bilirubin (TcB) levels were determined at the 3rd, 6th, 12th, 24th, 36th, 48th, 72nd, 96th, and 120th hour of life (HOL). A bilirubin nomogram was created using the averages of 3 TcB forehead and sternal measurements at each time epoch. Simultaneous measurement of TcB and total serum bilirubin (TsB) on a subset of 106 infants was done to determine correlation.

RESULTS

Correlation coefficients were high between TsB and forehead TcB (r² = 0.88), and between TsB and sternal TcB (r² = 0.91). The Filipino bilirubin nomogram reflected a steep rise until the 48th hour, followed by plateauing of values. Inadequate nursing and bilirubin levels at 12th and 48th HOL were risk factors for developing significant hyperbilirubinemia at 72nd HOL.

CONCLUSION

TcB is a reliable, non-invasive bilirubin screening tool. Among healthy, full-term, Filipino infants, their nomogram features a sudden increase in bilirubin values during the first 48 h, followed by a plateau. To aid in identification of infants at risk for significant hyperbilirubinemia, healthcare providers can assess breastfeeding adequacy and perform bilirubin screening at the 24th-48th HOL. Registration No. (RGAO-2016-0686).

Clinical predictive score of predischarge screening for severe hyperbilirubinemia in late preterm and term infants

BACKGROUND

Early identification and appropriate follow-up of infants at risk of severe hyperbilirubinemia are part of preventing complications. This study aims to develop the clinical predictive score to predict subsequent severe hyperbilirubinemia in healthy Thai infants.

METHODS

A case-control study was conducted using medical records of 147 hyperbilirubinemia cases and 147 age-matched controls among healthy late preterm and term Thai newborn infants during January 2015 and December 2016. The routinely measured TcB values at 48-54 hours of age and all predischarge clinical characteristics were collected. Multivariable logistic regression was used to find a clinical prediction model to predict subsequent severe hyperbilirubinemia within 7 days after birth which defined as a postdischarge bilirubin level exceeding the hour-specific recommended threshold for phototherapy by the American Academy of Pediatrics (AAP).

RESULTS

The best clinical predictors for subsequent severe hyperbilirubinemia were TcB values at 48-54 hours and gestational age of infants. Predischarge TcB at 48-54 hours of life was classified into 3 levels: < 10 mg/dL, 10-12 mg/dL and > 12 mg/dL. Gestational age was categorized into 5 groups. The risk score derived from these 2 significant factors predicted subsequent severe hyperbilirubinemia with an AuROC curve of 81.0% (95% CI: 76.2-85.9%) in 3 risk group, high, moderate and low. The positive likelihood ratio for subsequent severe hyperbilirubinemia of the high-risk group (score > 5) was 4.53 (95% CI: 2.91-7.04) with specificity of 87.1%. The negative predictive value of low-risk group (score < 3) was 81%.

CONCLUSIONS

A simple predischarge prediction score using gestational age and TcB values at 48-54 hours of life was developed. This score classified late preterm and term newborn infants into 3 distinct risk levels and may be useful to identify high-risk infants for outpatient follow-up of subsequent severe hyperbilirubinemia.

Transcutaneous bilirubin nomogram for evaluating the risk of hyperbilirubinemia in Iranian healthy newborns

BACKGROUND

Hyperbilirubinemia, which is mostly benign, is one of the most common problems in neonates. This study was conducted to draw a skin bilirubin nomogram for evaluating the risk of hyperbilirubinemia requiring treatment.

METHODS

This cross-sectional study recruited 1066 healthy infants. The first transcutaneous bilirubin (TcB) measurement was performed before hospital discharge and within 12-48 h of birth. The neonates were followed up for 6 days after discharge based on their age at the time of discharge. The neonates were divided into four groups based on the TcB values before discharge and age in hours, including the low-risk, medium-low-risk, medium-high-risk and high-risk groups. The percentage of neonates who progressed toward severe hyperbilirubinemia was then calculated in each percentile based on the follow-up TcB measurement. Stata software was used to draw the nomogram. Based on the TcB values at discharge and the neonate's age in hours, the skin bilirubin nomogram was drawn in 40, 75 and 95 percentiles.

RESULTS

A total of 4.9% of the neonates were in the high-risk group, 18.9% in the medium-high-risk group, 34.8% in the medium-low-risk group and 41.2% in the low-risk group. The risk of severe jaundice in the follow-up of the neonates in the highest-risk to the lowest-risk groups was 48.9, 14.5, 9.7 and 3.3%, respectively.

CONCLUSION

The skin bilirubin nomogram can be used to predict severe hyperbilirubinemia in Iranian infants.

Bilirubin nomograms for identification of neonatal hyperbilirubinemia in healthy term and late-preterm infants: a systematic review and meta-analysis

BACKGROUND

Hyperbilirubinemia occurs in most healthy term and late-preterm infants, and must be monitored to identify those who might develop severe hyperbilirubinemia. Total serum bilirubin (TSB) or transcutaneous bilirubin (TcB) nomograms have been developed and validated to identify neonatal hyperbilirubinemia. This study aimed to review previously published studies and compare the TcB nomograms with the TSB nomogram, and to determine if the former has the same predictive value for significant hyperbilirubinemia as TSB nomogram does.

METHODS

A predefined search strategy and inclusion criteria were set up. We selected studies assessing the predictive ability of TSB/TcB nomograms to identify significant hyperbilirubinemia in healthy term and late-preterm infants. Two independent reviewers assessed the quality and extracted the data from the included studies. Meta-Disc 1.4 analysis software was used to calculate the pooled sensitivity, specificity, and positive likelihood ratio of TcB/TSB nomograms. A pooled summary of the receiver operating characteristic of the TcB/TSB nomograms was created.

RESULTS

After screening 187 publications from electronic database searches and reference lists of eligible articles, we included 14 studies in the systematic review and meta-analysis. Eleven studies were of medium methodological quality. The remaining three studies were of low methodological quality. Seven studies evaluated the TcB nomograms, and seven studies assessed TSB nomograms. There were no differences between the predictive abilities of the TSB and TcB nomograms (the pooled area under curve was 0.819 vs. 0.817).

CONCLUSIONS

This study showed that TcB nomograms had the same predictive value as TSB nomograms, both of which could be used to identify subsequent significant hyperbilirubinemia. But this result should be interpreted cautiously because some methodological limitations of these included studies were identified in this review.

Accuracy of transcutaneous bilirubin measurement in preterm low-birth-weight neonates

The objective of this study was to evaluate the correlation and agreement between transcutaneous and serum bilirubin among preterm low-birth-weight neonates. Neonates born at <35 weeks of gestation with birth weight <2,000 g were enrolled prospectively. Transcutaneous bilirubin (TcB) was measured at forehead, sternum, and abdomen at 24 ± 6 and 72 ± 12 h after birth and when icterus involved arms or legs (Kramer zone 4-5). Serum total bilirubin (STB) was measured by microbilimeter (STB-M) at all these time-points and by high-performance liquid chromatography (STB-H) at one randomly chosen time-point. A total of 1,619 observations were made in 256 neonates (median gestation, 34 weeks (IQR, 32-35), birth weight 1,522 ± 288 g). Overall there was excellent correlation and agreement between TcB and STB-M with TcB on forehead being most accurate (r = 0.84, mean difference, 0.3 ± 1.9 mg/dL) followed by TcB on abdomen (r = 0.73, mean difference, 1.5 ± 2.6 mg/dL) and sternum (r = 0.72, mean difference, 1.5 ± 2.6 mg/dL). TcB performed well at all three points of measurement with best correlations being observed at icterus level 4/5. Correlation between TcB and STB-H measured by high-performance liquid chromatography was less strong but significant (r = 0.59 to 0.69 at different time points of measurement).

CONCLUSIONS

TcB has good correlation and agreement with STB in preterm low-birth-weight neonates born at ≥28 weeks of gestation.