Systematic review of screening for bilirubin encephalopathy in neonates

Transcutaneous bilirubinometry for detecting jaundice in term or late preterm neonates

BACKGROUND

The American Academy of Pediatrics and the Canadian Paediatric Society both advise that all newborns should undergo bilirubin screening before leaving the hospital, and this has become the standard practice in both countries. However, the US Preventive Task Force has found no strong evidence to suggest that this practice of universal screening for bilirubin reduces the occurrence of significant outcomes such as bilirubin-induced neurologic dysfunction or kernicterus.

OBJECTIVES

To evaluate the effectiveness of transcutaneous screening compared to visual inspection for hyperbilirubinemia to prevent the readmission of newborns (infants greater than 35 weeks' gestation) for phototherapy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, ClinicalTrials.gov, ICTRP, and ISRCTN in June 2023. We also searched conference proceedings, and the reference lists of included studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs), quasi-randomized, cluster-randomized, or prospective cohort studies with control arm that evaluated the use of transcutaneous bilirubin (TcB) screening for hyperbilirubinemia in newborns before hospital discharge.

DATA COLLECTION AND ANALYSIS

We used standard methodologic procedures expected by Cochrane. We evaluated treatment effects using a fixed-effect model with risk ratio (RR) and 95% confidence intervals (CI) for categorical data and mean, standard deviation (SD), and mean difference (MD) for continuous data. We used the GRADE approach to evaluate the certainty of evidence.

MAIN RESULTS

We identified one RCT that met our inclusion criteria. The study included 1858 African newborns at 35 weeks' gestation or greater who were receiving routine care at a well-baby nursery, and were randomly recruited prior to discharge to undergo TcB screening. The study had good methodologic quality. TcB screening versus visual assessment of hyperbilirubinemia in newborns: - probably reduces readmission to the hospital for hyperbilirubinemia (RR 0.25, 95% CI 0.14 to 0.46; P < 0.0001; moderate-certainty evidence); - may have little or no effect on the rate of exchange transfusion (RR 0.20, 95% CI 0.01 to 14.16; low-certainty evidence); - probably increases the number of newborns who require phototherapy prior to discharge (RR 2.67, 95% CI 1.56 to 4.55; moderate-certainty evidence). - may have little or no effect on the rate of acute bilirubin encephalopathy (RR 0.33, 95% CI 0.01 to 8.18; low-certainty evidence). The study did not evaluate or report cost of care.

AUTHORS' CONCLUSIONS

Moderate-certainty evidence suggests that TcB screening probably reduces hospital readmission for hyperbilirubinemia compared to visual inspection. Low-certainty evidence also suggests that TcB screening may have little or no effect on the rate of exchange transfusion compared to visual inspection. However, moderate-certainty evidence suggests that TcB screening probably increases the number of newborns that require phototherapy before discharge compared to visual inspection. Low-certainty evidence suggests that TcB screening may have little or no effect on the rate of acute bilirubin encephalopathy compared to visual inspection. Given that we have only identified one RCT, further studies are necessary to determine whether TcB screening can help to reduce readmission and complications related to neonatal hyperbilirubinemia. In settings with limited newborn follow-up after hospital discharge, identifying newborns at risk of severe hyperbilirubinemia before hospital discharge will be important to plan targeted follow-up of these infants.

Removing Race From Hyperbilirubinemia Guidelines Is Not Enough

This Viewpoint discusses the complexities of race-conscious medicine and the importance of more explicit and attentive guidance in treatment recommendations.

Primary risk stratification for neonatal jaundice among term neonates using machine learning algorithm

BACKGROUND

Neonatal jaundice occurs in approximately 60% of term newborns. Although risk factors for neonatal jaundice have been studied, all the suggested strategies are based on various newborn tests for bilirubin levels. We aim to stratify neonates into risk groups for clinically significant neonatal jaundice using a combined data analysis approach, without serum bilirubin evaluation.

STUDY DESIGN

Term (gestational week 37-42) neonates born in a single medical center, 2005-2018 were identified. Anonymized data were analyzed using machine learning. Thresholds for stratification into risk groups were established. Associations were evaluated statistically using neonates with and without clinically significant neonatal jaundice from the study population.

RESULTS

A total of 147,667 consecutive term live neonates were included. The machine learning diagnostic ability to evaluate the risk for neonatal jaundice was 0.748; 95% CI 0.743-0.754 (AUC). The most important factors were (in order of importance) maternal blood type, maternal age, gestational age at delivery, estimated birth weight, parity, CBC at admission, and maternal blood pressure at admission. Neonates were then stratified by risk: 61% (n = 90,140) were classed as low-risk, 39% (n = 57,527) as higher-risk. Prevalence of jaundice was 4.14% in the full cohort, and 1.47% and 8.29% in the low- and high-risk cohorts, respectively; OR 6.06 (CI: 5.7-6.45) for neonatal jaundice in high-risk group.

CONCLUSION

A population tailored "first step" screening policy using machine learning model presents potential of neonatal jaundice risk stratification for term neonates. Future development and validation of this computational model are warranted.

Infants affected by Rh sensitization: A 2-year Canadian National Surveillance Study

INTRODUCTION

Rh sensitization occurs when Rh(D)-negative women develop anti-Rh(D) antibodies following exposure through pregnancy or transfusion. Rh disease may cause jaundice, anemia, neurological impairment, and death. It is rare in countries where Rh Immune Globulin (RhIg) is used. Canadian Rh sensitization and disease rates are unknown.

METHODS

This survey-based study was conducted using a Canadian Paediatric Surveillance Program questionnaire sent to Canadian paediatricians and paediatric subspecialists to solicit Rh disease cases from May 2016 to June 2018. Paediatricians reported Rh-positive infants ≤ 60 days of age, born to Rh-negative mothers with RhD sensitization.

RESULTS

Sixty-two confirmed cases of infants affected by Rh(D) sensitization were reported across Canada. The median gestational age of neonates was term, age at presentation was 2 hours, and hemoglobin at presentation was 137.5 g/L (33 to 203 g/L). The median peak bilirubin and phototherapy duration were 280 µmol/L (92 to 771 µmol/L), and 124 hours, respectively. Thirty (48%) infants received Intravenous immune globulin (IVIG) (median two doses). Seventeen (27%) received one to three simple transfusions; 10 (16%) required exchange transfusions. Six (10%) infants presented with acute bilirubin encephalopathy, and less than five presented with seizures. Fourteen mothers with affected infants were born outside of Canada.

DISCUSSION

Rh disease continues to exist in Canada. Additional efforts are needed to raise awareness of Rh disease, prevent disease, and minimize sequelae when it does occur. The ongoing global burden of Rh Disease, as well as the possibility of emerging Rh immunoglobulin refusal are among factors that could be taken into consideration in future prevention efforts.

The Association between Serum Bilirubin and Kernicterus Spectrum Disorder: A Systematic Review and Meta-Analysis

BACKGROUND

Total serum bilirubin (TSB) is used in managing neonates with jaundice, but clear evidence on its association with major outcomes is lacking.

OBJECTIVES

We evaluated the association between TSB and kernicterus spectrum disorder (KSD).

METHODS

We searched PubMed, EMBASE, and CENTRAL till July 2021. Two authors independently selected relevant cohort studies, extracted data (CHARMS checklist), assessed risk of bias (RoB) (QUIPS tool), and rated certainty-of-evidence (Grades of Recommendation, Assessment, Development, and Evaluation). We pooled adjusted odds ratio (aOR) (random-effect) via generic inverse variance methods.

RESULTS

From 2,826 records retrieved, we included 37 studies (n = 648,979). Fifteen studies had low, 16 moderate, and 6 high RoB, with majority having concerns on confounder adjustment and statistical analysis. Twenty-two studies contributed meta-analysis data, and 15 were summarized narratively. TSB appears associated with KSD in infants with certain risk factors (aOR 1.10, 95% CI: 1.07-1.13; 5 studies [n = 4,484]). However, TSB (aOR 1.10, 95% CI: 0.98-1.23; 1 study [n = 34,533]) or hyperbilirubinemia (aOR 1.00, 95% CI: 0.51-1.95; 2 studies [n = 56,578]) have no clear association with kernicterus or neurological diagnosis in overall neonatal population (moderate-certainty-evidence). One study shows that infants with hyperbilirubinemia appear likelier to develop attention-deficit disorder (aOR 1.90, 95% CI: 1.10-3.28) and autistic spectrum disorder (aOR 1.60, 95% CI: 1.03-2.49, n = 56,019) (low-certainty-evidence). Certain clinical factors appear associated with KSD, although very few studies contributed to the analyses.

CONCLUSIONS

Despite the importance of this question, there is insufficient high-quality evidence on the independent prognostic value of TSB for adverse neurodevelopmental outcomes in most neonatal populations. Future studies should incorporate all known risk factors alongside TSB in a multivariable analysis to improve certainty-of-evidence.

Increased serum total bilirubin-albumin ratio was associated with bilirubin encephalopathy in neonates

We performed the present study to summarize the recent epidemiological characteristics of bilirubin encephalopathy and assess the role of total bilirubin-albumin ratio in the bilirubin encephalopathy. We retrospectively collected clinical data of 669 neonates with hyperbilirubinemia from the First Affiliated Hospital of Zhengzhou University between January 2015 and July 2018, including 153 neonates belonged to bilirubin encephalopathy and 516 ones were treated as control group. Compared with the control group, those with bilirubin encephalopathy have higher bilirubin-albumin ratio (13.8 ± 3.6 vs. 10.6 ± 2.5, P=0.000). The direct bilirubin and indirect bilirubin level were higher in the case group than that in the control group (P=0.000). On the contrary, the hemoglobin level was lower in the case group than that in the control group (P=0.004). There were no significant differences in gestational age (P=0.510), gender rate (P=0.313), maternal gestational diabetes ratio (P=0.071), natural childbirth ratio (P=0.686), and meconium delay (P=0.091). The results from univariate regression indicated the total bilirubin/albumin ratio was positively associated with bilirubin encephalopathy (odds ratio (OR) = 1.67, 95% confidence interval (CI): 1.59-3.14). The total bilirubin, direct bilirubin, and indirect bilirubin were also related to encephalopathy. After adjusting some potential cofounding factors, the total bilirubin-albumin was still associated with bilirubin encephalopathy. The higher total bilirubin-albumin ratio increased the risk of bilirubin encephalopathy by 23% (OR = 1.23, 95% CI: 1.16-2.48). Our results indicated that the bilirubin-albumin ratio is associated with bilirubin encephalopathy in neonates, and could be a potential predictor.

High unbound bilirubin for age: a neurotoxin with major effects on the developing brain

Neonatal hyperbilirubinemia is one of the most frequent diagnoses made in neonates. A high level of unconjugated bilirubin that is unbound to albumin is neurotoxic when the level exceeds age-specific thresholds or at lower levels in neonates with neurotoxic risk factors. Lower range of unbound bilirubin results in apoptosis, while moderate-to-high levels result in neuronal necrosis. Basal ganglia and various brain stem nuclei are more susceptible to bilirubin toxicity. Proposed mechanisms of bilirubin-induced neurotoxicity include excessive release of glutamate, mitochondrial energy failure, release of proinflammatory cytokines, and increased intracellular calcium concentration. These mechanisms are similar to the events that occur following hypoxic-ischemic insult in neonates. Severe hyperbilirubinemia in term neonates has been shown to be associated with increased risk for autism spectrum disorders. The neuropathological finding of bilirubin-induced neurotoxicity also includes cerebellar injury with a decreased number of Purkinje cells, and disruption of multisensory feedback loop between cerebellum and cortical neurons which may explain the clinical characteristics of autism spectrum disorders. Severe hyperbilirubinemia occurs more frequently in infants from low- and middle-income countries (LMIC). Simple devices to measure bilirubin, and timely treatment are essential to reduce neurotoxicity, and improve outcomes for thousands of neonates around the world.

Identification of Genetic Risk Factors for Neonatal Hyperbilirubinemia in Fujian Province, Southeastern China: A Case-Control Study

To date, the genetic risk factors for neonatal hyperbilirubinemia remain unknown in Southeastern China. This case-control study aimed to identify the genetic risk factors for neonatal hyperbilirubinemia in Fujian, Southeastern China. A total of 286 hyperbilirubinemic newborns were enrolled as a case group, and 250 randomly selected newborns without jaundice or with a bilirubin level that was lower than the threshold required for phototherapy served as controls. The serum levels of total bilirubin, unconjugated bilirubin, and direct bilirubin were measured, and the common genetic loci in UGT1A1, OATP1B1, and HO-1 genes were genotyped. Higher incidence of ABO incompatibility and G6PD deficiency was detected in the case group compared to the control group (P < 0.01). There were significant differences in the frequencies of rs4148323 and rs1805173 genotypes between the case and control groups (P < 0.05). At the rs4148323 locus, the frequencies of GA heterozygotes and AA mutant homozygotes were higher in the case group than in the control group (P < 0.05), and at the rs1805173 locus, the frequencies of LS, MS, and SS genotypes were higher in the case group than in the control group (P < 0.05). A higher frequency of rs4148323 A allele and rs1805173 S allele was detected in the case group compared to the control group (P = 0). Additionally, multivariate logistic regression analysis identified that the mutant genotype of rs4148323 in the UGT1A1 gene, ABO incompatibility, G6PD deficiency, and SS genotype at rs1805173 locus of the HO-1 gene were genetic risk factors of neonatal hyperbilirubinemia. Our data demonstrate that G211 mutation in the UGT1A1 gene, ABO incompatibility, G6PD deficiency, and the SS genotype of the repeats in the promoter region of the HO-1 gene are risk factors for neonatal hyperbilirubinemia in Fujian, Southeastern China.

Fluid supplementation for neonatal unconjugated hyperbilirubinaemia

BACKGROUND

Neonatal hyperbilirubinaemia is a common problem which carries a risk of neurotoxicity. Certain infants who have hyperbilirubinaemia develop bilirubin encephalopathy and kernicterus which may lead to long-term disability. Phototherapy is currently the mainstay of treatment for neonatal hyperbilirubinaemia. Among the adjunctive measures to compliment the effects of phototherapy, fluid supplementation has been proposed to reduce serum bilirubin levels. The mechanism of action proposed includes direct dilutional effects of intravenous (IV) fluids, or enhancement of peristalsis to reduce enterohepatic circulation by oral fluid supplementation.

OBJECTIVES

To assess the risks and benefits of fluid supplementation compared to standard fluid management in term and preterm newborn infants with unconjugated hyperbilirubinaemia who require phototherapy.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 5), MEDLINE via PubMed (1966 to 7 June 2017), Embase (1980 to 7 June 2017), and CINAHL (1982 to 7 June 2017). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

We included randomised controlled trials that compared fluid supplementation against no fluid supplementation, or one form of fluid supplementation against another.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the Cochrane Neonatal Review Group using the Covidence platform. Two review authors independently assessed the eligibility and risk of bias of the retrieved records. We expressed our results using mean difference (MD), risk difference (RD), and risk ratio (RR) with 95% confidence intervals (CIs).

MAIN RESULTS

Out of 1449 articles screened, seven studies were included. Three articles were awaiting classification, among them, two completed trials identified from the trial registry appeared to be unpublished so far.There were two major comparisons: IV fluid supplementation versus no fluid supplementation (six studies) and IV fluid supplementation versus oral fluid supplementation (one study). A total of 494 term, healthy newborn infants with unconjugated hyperbilirubinaemia were evaluated. All studies were at high risk of bias for blinding of care personnel, five studies had unclear risk of bias for blinding of outcome assessors, and most studies had unclear risk of bias in allocation concealment. There was low- to moderate-quality evidence for all major outcomes.In the comparison between IV fluid supplementation and no supplementation, no infant in either group developed bilirubin encephalopathy in the one study that reported this outcome. Serum bilirubin was lower at four hours postintervention for infants who received IV fluid supplementation (MD -34.00 μmol/L (-1.99 mg/dL), 95% CI -52.29 (3.06) to -15.71 (0.92); participants = 67, study = 1) (low quality of evidence, downgraded one level for indirectness and one level for suspected publication bias). Beyond eight hours postintervention, serum bilirubin was similar between the two groups. Duration of phototherapy was significantly shorter for fluid-supplemented infants, but the estimate was affected by heterogeneity which was not clearly explained (MD -10.70 hours, 95% CI -15.55 to -5.85; participants = 218; studies = 3; I² = 67%). Fluid-supplemented infants were less likely to require exchange transfusion (RR 0.39, 95% CI 0.21 to 0.71; RD -0.01, 95% CI -0.04 to 0.02; participants = 462; studies = 6; I² = 72%) (low quality of evidence, downgraded one level due to inconsistency, and another level due to suspected publication bias), and the estimate was similarly affected by unexplained heterogeneity. The frequencies of breastfeeding were similar between the fluid-supplemented and non-supplemented infants in days one to three based on one study (estimate on day three: MD 0.90 feeds, 95% CI -0.40 to 2.20; participants = 60) (moderate quality of evidence, downgraded one level for imprecision).One study contributed to all outcome data in the comparison of IV versus oral fluid supplementation. In this comparison, no infant in either group developed abnormal neurological signs. Serum bilirubin, as well as the rate of change of serum bilirubin, were similar between the two groups at four hours after phototherapy (serum bilirubin: MD 11.00 μmol/L (0.64 mg/dL), 95% CI -21.58 (-1.26) to 43.58 (2.55); rate of change of serum bilirubin: MD 0.80 μmol/L/hour (0.05 mg/dL/hour), 95% CI -2.55 (-0.15) to 4.15 (0.24); participants = 54 in both outcomes) (moderate quality of evidence for both outcomes, downgraded one level for indirectness). The number of infants who required exchange transfusion was similar between the two groups (RR 1.60, 95% CI 0.60 to 4.27; RD 0.11, 95% CI -0.12 to 0.34; participants = 54). No infant in either group developed adverse effects including vomiting or abdominal distension.

AUTHORS' CONCLUSIONS

There is no evidence that IV fluid supplementation affects important clinical outcomes such as bilirubin encephalopathy, kernicterus, or cerebral palsy in healthy, term newborn infants with unconjugated hyperbilirubinaemia requiring phototherapy. In this review, no infant developed these bilirubin-associated clinical complications. Low- to moderate-quality evidence shows that there are differences in total serum bilirubin levels between fluid-supplemented and control groups at some time points but not at others, the clinical significance of which is uncertain. There is no evidence of a difference between the effectiveness of IV and oral fluid supplementations in reducing serum bilirubin. Similarly, no infant developed adverse events or complications from fluid supplementation such as vomiting or abdominal distension. This suggests a need for future research to focus on different population groups with possibly higher baseline risks of bilirubin-related neurological complications, such as preterm or low birthweight infants, infants with haemolytic hyperbilirubinaemia, as well as infants with dehydration for comparison of different fluid supplementation regimen.

Phototherapy for the Treatment of Neonatal Jaundice and Breastfeeding Duration and Exclusivity

INTRODUCTION

Because neonatal jaundice remains one of the most commonly treated conditions of the newborn infant, it is important to assess the unintended consequences of treatment with phototherapy. The objective of this study was to evaluate whether treatment with phototherapy affects breastfeeding duration in newborns >35 weeks gestation.

MATERIALS AND METHODS

We analyzed data from the Infant Feeding Practices Study II. The exposure of interest was treatment of neonatal jaundice with phototherapy. The outcomes of interest were any breastfeeding through 12 months and exclusive breastfeeding through 4 months. Logistic regression models were developed to evaluate the association between the exposure and outcomes of interest. All models were adjusted for maternal age, race, education, household income, and gestational age, as well as for several potential markers of suboptimal breastfeeding.

RESULTS

Our study included 4,441 infants, of which 220 (5%) received phototherapy. We found no difference in the likelihood of any breastfeeding through 9 months of age, however, by 12 months, infants exposed to phototherapy were less likely to still be breastfed than those who were not exposed (adjusted odds ratio [aOR] 0.58, 95% confidence interval [95% CI] 0.37-0.92). Infants exposed to phototherapy were less likely to be exclusively breastfed throughout the first 4 months of life.

CONCLUSION

Although phototherapy use did not substantially impact rates of any breastfeeding during the first year, it was associated with decreased rates of exclusive breastfeeding in the first 4 months of life. This suggests that we need to tailor messaging to mothers of infants receiving phototherapy to promote exclusive breastfeeding.

Supporting breastfeeding to reduce newborn readmissions for hyperbilirubinemia

Lack of breastfeeding support can result in inadequate feedings at the breast, putting newborns at risk for hyperbilirubinemia, severe jaundice and possible hospital readmission. Nurses can help prevent readmissions for hyperbilirubinemia by becoming educated about the risk factors for hyperbilirubinemia and by implementing preventive measures through improved breastfeeding support.

Societal impact of bilirubin-induced hearing impairment in resource-limited nations

Infants with bilirubin-induced neurologic dysfunction (BIND) are characterized by several developmental disabilities including auditory impairments. This paper explores the societal impact of bilirubin-induced auditory impairments, inclusive of hearing impairments and auditory neuropathy spectrum disorders, on these infants, their families, and on the community in resource-limited countries (per capita income of US$6,000 or less). Auditory impairments have substantial emotional, social, and economic impact on the affected infants, their families and communities. The burden is exacerbated by widespread poverty, unfavorable community attitudes towards disabilities, and lack of requisite health, educational, and social services. Curtailing the incidence of avoidable severe hyperbilirubinemia through proactive and effective management of infants at risk or with severe hyperbilirubinemia is necessary at all levels of healthcare delivery. Early detection and intervention for unavoidable auditory impairments should be widely promoted to provide improved developmental trajectories for the affected infants.

Transcutaneous bilirubinometry

Although the modern era of transcutaneous bilirubin monitoring (TcB) began only about 35 years ago, this screening tool is now widely used in newborn nurseries and outpatient clinics, offices, and emergency departments to obtain a rapid and non-invasive estimate of the degree of hyperbilirubinemia. TcB devices have become more sophisticated, and major breakthroughs include the following: (a) ability to report a bilirubin value rather than an index value, (b) enhanced correction for chromophores other than bilirubin, and (c) technologic improvements including interface with electronic medical records. Good agreement with laboratory bilirubin measurement has been demonstrated, and the ability of TcB screening to predict and decrease the incidence of subsequent hyperbilirubinemia has been well-documented. To date, it has not been shown that this screening results in improved long-term outcomes.

Universal bilirubin screening and health care utilization

OBJECTIVE

To evaluate the impact of the implementation of universal bilirubin screening on neonatal health care use in the context of a large jurisdiction with universal health insurance.

METHODS

We conducted a population-based retrospective cohort study of all newborns discharged after birth between April 2003 and February 2011 from 42 hospitals that implemented universal bilirubin screening between July 2007 and June 2010 in Ontario, Canada. We surveyed hospitals to determine their screening implementation date. We used multiple linked administrative health data sets to measure phototherapy use, length of stay (LOS), jaundice-related emergency department visits, and jaundice-related readmissions. We modeled the relationship between universal bilirubin screening and outcomes using generalized estimating equations to account for clustering by hospital, underlying temporal trends, and important covariates.

RESULTS

Screening was associated with an increase in phototherapy during hospitalization at birth (relative risk, 1.32; 95% confidence interval, 1.09-1.59) and a decrease in jaundice-related emergency department visits (relative risk, 0.79; 95% confidence interval, 0.64-0.96) but no statistically significant difference in phototherapy after discharge, LOS, or jaundice-related readmissions after accounting for preexisting temporal trends in health care service use and other patient sociodemographic and hospital characteristics.

CONCLUSIONS

Universal bilirubin screening may not be associated with increased neonatal LOS or increased subsequent hospital use. Our findings are relevant for determining the resource implications of universal bilirubin screening in Ontario. They highlight the limitations in generalizability of previous research on health care utilization associated with similar programs and underline the importance of context-specific local evaluation of guideline implementation.

Sixth hour transcutaneous bilirubin predicting significant hyperbilirubinemia in ABO incompatible neonates

BACKGROUND

Neonates with ABO hemolytic disease are at greater risk for developing significant hyperbilirubinemia. We aimed to determine whether sixth hour transcutaneous bilirubin (TcB) could predict such a risk.

METHODS

TcB measurements were obtained at the 6th hour of life in blood group A or B neonates born to blood group O, rhesus factor compatible mothers. Subsequent hyperbilirubinemia was monitored and considered significant if a neonate required phototherapy/exchange transfusion. The predictive role of sixth hour TcB was estimated.

RESULTS

Of 144 ABO incompatible neonates, 41(OA, 24; O-B, 17) had significant hyperbilirubinemia. Mean sixth hour TcB was significantly higher among neonates who developed significant hyperbilirubinemia than those who did not (5.83±1.35 mg/dL vs. 3.65±0.96 mg/dL, P<0.001). Sixth hour TcB value >4 mg/dL had the highest sensitivity of 93.5% and >6 mg/dL had the highest specificity of 99%. Area under receiver operating characteristic curve was 0.898.

CONCLUSION

Sixth hour TcB predicts subsequent significant hyperbilirubinemia in ABO incompatible neonates.

Neonatal hyperbilirubinemia and Rhesus disease of the newborn: incidence and impairment estimates for 2010 at regional and global levels

BACKGROUND

Rhesus (Rh) disease and extreme hyperbilirubinemia (EHB) result in neonatal mortality and long-term neurodevelopmental impairment, yet there are no estimates of their burden.

METHODS

Systematic reviews and meta-analyses were undertaken of national prevalence, mortality, and kernicterus due to Rh disease and EHB. We applied a compartmental model to estimate neonatal survivors and impairment cases for 2010.

RESULTS

Twenty-four million (18% of 134 million live births ≥ 32 wk gestational age from 184 countries; uncertainty range: 23-26 million) were at risk for neonatal hyperbilirubinemia-related adverse outcomes. Of these, 480,700 (0.36%) had either Rh disease (373,300; uncertainty range: 271,800-477,500) or developed EHB from other causes (107,400; uncertainty range: 57,000-131,000), with a 24% risk for death (114,100; uncertainty range: 59,700-172,000), 13% for kernicterus (75,400), and 11% for stillbirths. Three-quarters of mortality occurred in sub-Saharan Africa and South Asia. Kernicterus with Rh disease ranged from 38, 28, 28, and 25/100,000 live births for Eastern Europe/Central Asian, sub-Saharan African, South Asian, and Latin American regions, respectively. More than 83% of survivors with kernicterus had one or more impairments.

CONCLUSION

Failure to prevent Rh sensitization and manage neonatal hyperbilirubinemia results in 114,100 avoidable neonatal deaths and many children grow up with disabilities. Proven solutions remain underused, especially in low-income countries.

Predischarge screening for severe neonatal hyperbilirubinemia identifies infants who need phototherapy

OBJECTIVE

To test whether the combined use of total plasma/serum bilirubin (TSB) levels and clinical risk factors more accurately identifies infants who receive phototherapy than does the use of either method alone.

STUDY DESIGN

We recruited healthy infants of ≥35 weeks' gestation at 6 centers that practiced universal predischarge TSB screening. Transcutaneous bilirubin (TcB) was measured at 24 hours, with TSB at 24-60 hours and at 3- to 5- and 7- to 14-day follow-up visits. Clinical risk factors were identified systematically.

RESULTS

Of 1157 infants, 1060 (92%) completed follow-up, and 982 (85%) had complete datasets for analysis. Infant characteristics included 25% were nonwhite and 55% were Hispanic/Latino; >90% were breastfed. During the first week, jaundice was documented in 84% of subjects. Predischarge TSB identified the 41 (4.2%) and 34 (3.5%) infants who received phototherapy before and after discharge, respectively. Prediction of postdischarge phototherapy was similar for combined clinical risk factors (earlier gestational age [GA], bruising, positive direct antiglobulin test, Asian race, exclusive breastfeeding, blood type incompatibility, jaundice extent) and age-adjusted TSB (area under the curve [AUC] = .86 vs .87), but combined screening was better (AUC = .95). TcB/TSB combined with GA alone was equally predictive (AUC = .95; 95% CI .93-.97).

CONCLUSIONS

Jaundice is present in 4 of 5 (84%) healthy newborns. Predischarge TcB/TSB (adjusted for postnatal age) combined with specific clinical factors (especially GA) best predicts subsequent phototherapy use. Universal implementation of this strategy in the US should improve outcomes of healthy newborns discharged early.

Predischarge non-invasive risk assessment for prediction of significant hyperbilirubinemia in term and late preterm neonates

OBJECTIVE

To evaluate efficacy of predischarge transcutaneous bilirubin (TcB) measurement and clinical risk assessment in predicting hyperbilirubinemia needing treatment.

STUDY DESIGN

A diagnostic test was performed in a prospective cohort study conducted at a teaching hospital in North India. Subjects included healthy neonates with a gestation period of ≥35 weeks or birth weight ≥2000 g. Maternal, neonatal and delivery risk factors for hyperbilirubinemia were prospectively collected. TcB was measured in all enrolled neonates at 24±6, 72 to 96 and 96 to 144 h of postnatal age and when indicated clinically. Neonates were followed up during hospital stay and after discharge till completion of the 7th postnatal day. The key outcome was significant hyperbilirubinemia defined as need of phototherapy on the basis of modified American Academy of Pediatrics guidelines. In neonates born at ≥38 weeks of gestation and in neonates born at ≤37 completed weeks of gestation, middle line and lower line of phototherapy thresholds were used to initiate phototherapy, respectively. Variables observed to be significantly associated with significant hyperbilirubinemia on multivariate analysis were used for construction of a clinical risk assessment tool. Predictive ability of the risk assessment tool was assessed by calculating sensitivity, specificity, positive predictive value and negative predictive value, by plotting receiver-operating characteristics curve and calculating c-statistic.

RESULT

A total of 997 neonates (birth weight: 2627±536 g, gestation: 37.8±1.5 weeks) were enrolled in the study, of which 931 completed follow-up. Among enrolled neonates, 344 (34.5%) were low birth weight. Overall, a total of 199 (20%) neonates developed significant hyperbilirubinemia. On stepwise logistic regression analysis, predischarge TcB percentile and gestation were significantly found to be associated with significant hyperbilirubinemia. A risk assessment graph was constructed to predict subsequent development of significant hyperbilirubinemia. Area under curve for this risk assessment strategy was 0.75.

CONCLUSION

A risk assessment graphical tool consisting of TcB and gestation accurately predicted subsequent need of phototherapy. Further studies are needed to validate performance of this risk assessment tool.

Neonatal cholestasis: opportunities to increase early detection

OBJECTIVE

To describe primary care management of early and prolonged jaundice in otherwise-healthy term infants to identify opportunities to increase early diagnosis of cholestasis.

METHODS

Community-based pediatricians in St Louis, Missouri completed a mailed, anonymous, 29-item survey to assess practice demographics, timing of routine newborn office visits, and the management of early and prolonged neonatal jaundice.

RESULTS

A total of 108 of 230 (47%) of eligible physicians responded (mean years in practice, 15.3, SD, 9.4). More respondents were very familiar with national guidelines for management of early (49%) than prolonged (16%) neonatal jaundice. Eighty-six percent reported all newborns were checked with transcutaneous bilirubin before hospital discharge. For transcutaneous bilirubin results at 48 hours of 7, 10, 12 and 15 mg/dL, 1%, 26%, 70%, and 74% of respondents, respectively, would order a fractionated bilirubin. Although the first routine visit usually occurred in the first week after discharge, 25% of physicians reported the 2nd visit was routinely scheduled after 4 weeks of age. Ninety-four percent reported they would obtain a fractionated bilirubin for infants jaundiced beyond 4 weeks of age. If cholestasis was identified at 6 weeks of age, 32% would obtain additional testing without referral to a subspecialist.

CONCLUSIONS

Management of early and prolonged neonatal jaundice is variable. Current practices appear to miss opportunities for early diagnosis of cholestasis and referral that are unlikely to be addressed without redesigning systems of care.

Chapter 8: meta-analysis of test performance when there is a "gold standard"

Synthesizing information on test performance metrics such as sensitivity, specificity, predictive values and likelihood ratios is often an important part of a systematic review of a medical test. Because many metrics of test performance are of interest, the meta-analysis of medical tests is more complex than the meta-analysis of interventions or associations. Sometimes, a helpful way to summarize medical test studies is to provide a "summary point", a summary sensitivity and a summary specificity. Other times, when the sensitivity or specificity estimates vary widely or when the test threshold varies, it is more helpful to synthesize data using a "summary line" that describes how the average sensitivity changes with the average specificity. Choosing the most helpful summary is subjective, and in some cases both summaries provide meaningful and complementary information. Because sensitivity and specificity are not independent across studies, the meta-analysis of medical tests is fundamentaly a multivariate problem, and should be addressed with multivariate methods. More complex analyses are needed if studies report results at multiple thresholds for positive tests. At the same time, quantitative analyses are used to explore and explain any observed dissimilarity (heterogeneity) in the results of the examined studies. This can be performed in the context of proper (multivariate) meta-regressions.

Total serum bilirubin exceeding exchange transfusion thresholds in the setting of universal screening

OBJECTIVE

To describe the incidence and predictors of total serum bilirubin (TSB) levels that meet or exceed American Academy of Pediatrics (AAP) exchange transfusion (ET) thresholds in the setting of universal screening.

STUDY DESIGN

We conducted a retrospective cohort analysis of electronic data on 18 089 newborns ≥35 weeks gestation born at Northern California Kaiser Permanente Medical Care Program hospitals implementing universal TSB screening in 2005 to 2007, with chart review for subjects with TSB levels reaching the AAP threshold for ET.

RESULTS

The outcome developed in 22 infants (0.12%); 14 (63.6%) were <38 weeks gestation. Only one infant received an ET; none of the infants had documented sequelae. The first TSB was at least high-intermediate risk on the AAP risk-nomogram for all 22 infants and high-risk for those ≥38 weeks, but was less than the phototherapy level in 15 infants (68%). Of these 15 infants, 2 failed phototherapy and 13 did not have a TSB repeated in <24 hours. However, re-testing all infants at high-intermediate risk or greater would have required 2166 additional bilirubin tests.

CONCLUSION

Screening was sensitive but not specific for predicting exchange threshold.

Transcutaneous bilirubin measurement methods in neonates and its utility for emergency department use

Transcutaneous bilirubin measurements correlate with serum bilirubin measurements in neonates. They permit rapid measurements but do not provide fractionation information. Background information of bilirubin measurements is reviewed. The role of transcutaneous bilirubin measurements in the emergency department is reviewed.

An evidence-based view on hyperbilirubinaemia

INTRODUCTION

We conducted a review of the evidence which contributes to the current care of jaundiced newborn infants.

METHODS

Literature was searched for reviews and randomized controlled trials (RCTs).

RESULTS

Six Cochrane reviews and eight other reviews and eighteen recent RCTs are discussed.

CONCLUSIONS

Many children still suffer life-long consequences of severe hyperbilirubinaemia, which could almost always have been prevented relatively easily. Up to date, guidelines summarizing the available evidence into unambiguous recommendations are needed to guide healthcare professionals in the prevention, diagnosis and treatment for infants with hyperbilirubinaemia.

Impact of a transcutaneous bilirubinometry program on resource utilization and severe hyperbilirubinemia

OBJECTIVES

Our goal was to assess the impact of programmatic and coordinated use of transcutaneous bilirubinometry (TcB) on the incidence of severe neonatal hyperbilirubinemia and measures of laboratory, hospital, and nursing resource utilization.

METHODS

We compared the neonatal hyperbilirubinemia-related outcomes of 14 796 prospectively enrolled healthy infants ≥35 weeks gestation offered routine TcB measurements in both hospital and community settings by using locally validated nomograms relative to a historical cohort of 14 112 infants assessed by visual inspection alone.

RESULTS

There was a 54.9% reduction (odds ratio [OR]: 2.219 [95% confidence interval (CI): 1.543-3.193]; P < .0001) in the incidence of severe total serum bilirubin values (≥342 µmol/L; ≥20 mg/dL) after implementation of routine TcB measurements. TcB implementation was associated with reductions in the overall incidence of total serum bilirubin draws (134.4 vs 103.6 draws per 1000 live births, OR: 1.332 [95% CI: 1.226-1.446]; P < .0001) and overall phototherapy rate (5.27% vs 4.30%, OR: 1.241 [95% CI: 1.122-1.374]; P < .0001), a reduced age at readmission for phototherapy (104.3 ± 52.1 vs 88.9 ± 70.5 hours, P < .005), and duration of phototherapy readmission (24.8 ± 13.6 vs 23.2 ± 9.8 hours, P < .05). There were earlier (P < .01) and more frequent contacts with public health nurses (1.33 vs 1.66, P < .01) after introduction of the TcB program.

CONCLUSIONS

Integration of routine hospital and community TcB screening within a comprehensive public health nurse newborn follow-up program is associated with significant improvements in resource utilization and patient safety.

Patients with biliary atresia have elevated direct/conjugated bilirubin levels shortly after birth

OBJECTIVES

Healthy infants are thought to acquire biliary atresia (BA) in the first weeks of life. Because those diagnosed earlier have better outcomes, we were interested in determining the earliest time BA could be detected. We started by examining the immediate postnatal period, hypothesizing that newborns would not yet have acquired disease and still have normal direct/conjugated bilirubin (DB/CB) levels.

PATIENTS AND METHODS

Newborn DB/CB levels were obtained retrospectively from birth hospitals. Subjects with BA were born between 2007 and 2010 and cared for at Texas Children's Hospital. Those with BA splenic malformation syndrome or born prematurely were excluded. Control subjects were term newborns who later never developed neonatal liver disease.

RESULTS

Of the 61 subjects with BA, 56% had newborn DB/CB levels measured. All DB/CB levels exceeded laboratory norms and rose over time. At 24 to 48 hours of life, subjects with BA had mean DB levels significantly higher than those of controls (1.4 ± 0.43 vs. 0.19 ± 0.075 mg/dL, P < .0001), even while their mean total bilirubin (TB) levels remained below phototherapy limits. Finally, despite the elevated DB/CB levels, the majority of patients (79%) had normal DB:TB ratios ≤ 0.2.

CONCLUSIONS

Patients with BA have elevated DB/CB levels shortly after birth. To detect affected infants earlier and improve outcomes, the results suggest two possibilities: (1) screen all newborns for elevated DB/CB levels, rather than just those who appear jaundiced; and then (2) follow all newborns with elevated DB/CB levels, rather than just those with DB:TB ratios >0.2.

The need for technologies to prevent bilirubin-induced neurologic dysfunction syndrome

Dramatic improvements in the overall socioeconomic conditions have yet to impact the unacceptably high maternal (approximately 1500 maternal deaths daily, worldwide) and neonatal morbidity and mortality (more than 10,000 deaths per daily 200,000 live-births, worldwide) in the developing nations. Thus, nations with emerging markets have unique health-societal needs. All infants require a safer transition from a birthing facility to home during the first week after birth and providing for a nurturing environment to prevent neonatal illnesses is integral to "good clinical practice." The unmonitored occurrence of severe hyperbilirubinemia and kernicterus are emblematic of a fractured maternal child healthcare system. The "know-do" gaps that span private versus public health care systems in the emerging markets have led us to conclude that building an interdisciplinary leadership approach to provide innovative strategies and affordable technologies will help bridge and access existing social barriers in the micro- and macro-health environments. Thus, unfettered access, global benchmarks, and culturally relevant strategies are dependent on evidence-based affordable technologies to successfully transform societal health care practices. Implementation of jaundice-related technologies should serve as a template for other affordable newborn health products.

A global need for affordable neonatal jaundice technologies

Globally, health care providers worldwide recognize that severe neonatal jaundice is a "silent" cause of significant neonatal morbidity and mortality. Untreated neonatal jaundice can lead to death in the neonatal period and to kernicterus, a major cause of neurologic disability (choreo-athetoid cerebral palsy, deafness, language difficulty) in children who survive this largely preventable neonatal tragedy. Appropriate technologies are urgently needed. These include tools to promote and enhance visual assessment of the degree of jaundice, such as simpler transcutaneous bilirubin measurements and readily available serum bilirubin measurements that could be incorporated into routine treatment and follow-up. Widespread screening for glucose-6-phoshate dehydrogenase deficiency is needed because this is often a major cause of neonatal jaundice and kernicterus worldwide. Recognition and treatment of Rh hemolytic disease, another known preventable cause of kernicterus, is critical. In addition, effective phototherapy is crucial if we are to make kernicterus a "never-event." Finally it is essential that we conduct appropriate population-based studies to accurately elucidate the magnitude of the problem. However, knowledge alone is not sufficient. If we are to implement these and other programs and technologies to relegate severe neonatal jaundice and its sequelae to the history books, screening and interventions must be low cost and technologically appropriate for low and middle income nations.

Universal bilirubin screening for severe neonatal hyperbilirubinemia

To reduce the incidence of severe neonatal hyperbilirubinemia affecting newborns with jaundice in the United States and to prevent kernicterus, there is a need to implement proven prevention strategies for severe neonatal hyperbilirubinemia as recommended in the 2004 American Academy of Pediatrics Guidelines for newborns >35 weeks gestational age. The purpose of universal predischarge bilirubin screening is to identify infants with bilirubin levels >75th percentile for age in hours and track those with rapid rates of bilirubin rise (>0.2 mg per 100 ml per h). Early identification has been reported to predict severe hyperbilirubinemia and allow for evidence-based targeted interventions. A systems approach is likely to reduce the preventable causes of acute bilirubin encephalopathy. To do so, highest priority should be given to (i) designating extreme hyperbilirubinemia (total serum bilirubin >427 μmol l(-1) or >25 mg per 100 ml) as a reportable condition by laboratories and health-care providers through public health mandates; (ii) implementation of Joint Commission's Sentinel Report for kernicterus; (iii) nursing outreach to communities for education of prospective parents; (iv) development of clinical pathways to monitor, evaluate and track infants with extreme hyperbilirubinemia; and (v) societal awareness. These efforts should be monitored by a state and national surveillance system in order to critically improve the timeliness and completeness of notifications and to allow evaluation and interventions at the policy and individual family level.

The northern california perinatal research unit: a hybrid model bridging research, quality improvement and clinical practice

Kaiser Permanente (KP) has a long-standing commitment to conduct research and report publicly. Simultaneously, it faces a different imperative: harnessing information systems to leverage internal improvements in outcomes, efficiency, and costs. Now that KP HealthConnect, the KP electronic health record, is fully implemented, research challenges at KP are moving away from issues of data access and toward the mechanisms through which raw data create meaningful clinical knowledge that is based on rigorous research. In this report we describe a model for research-the Northern California Division of Research Perinatal Research Unit-that leverages internal and external resources to fulfill these twin missions.

Screening and early postnatal management strategies to prevent hazardous hyperbilirubinemia in newborns of 35 or more weeks of gestation

Although kernicterus is a rare condition, it is still being reported in North America and Western Europe in addition to less developed parts of the world. The majority of affected infants are term and late-preterm newborns who have been discharged from the nursery as 'healthy newborns' yet have subsequently developed extreme hyperbilirubinemia and the classic neurodevelopmental findings associated with kernicterus. Published guidelines provide the basic tools for preventing hazardous hyperbilirubinemia and the two most important of these are a systematic assessment, prior to discharge, of each infant, for the risk of severe hyperbilirubinemia, and appropriate follow-up based on the time of discharge and the risk assessment. The most recent recommendations call for a predischarge measurement of the serum or transcutaneous bilirubin in all infants. When combined with the gestational age and other risk factors for hyperbilirubinemia, this provides the best estimate of the risk, or lack of risk, for subsequent hyperbilirubinemia, and determines the timing of follow-up and the need for further evaluation and treatment. The application of these principles to the management of the jaundiced newborn might not eliminate every case of kernicterus, but should contribute to a reduction in its occurrence.

Assessing jaundice in infants of 35-week gestation and greater

PURPOSE OF REVIEW

In 2004, the American Academy of Pediatrics officially recommended universal predischarge risk assessment for severe neonatal hyperbilirubinemia with the goal of minimizing subsequent risk of chronic bilirubin encephalopathy (formerly known as kernicterus). In this article, we review recent research regarding jaundice predischarge risk assessment, current expert recommendations for universal predischarge bilirubin screening, and concerns expressed in the literature regarding these recommendations.

RECENT FINDINGS

A group of experts have recently recommended universal predischarge bilirubin screening to identify newborns at risk for developing severe neonatal hyperbilirubinemia. In contrast, the United States Preventive Services Task Force states that there is insufficient evidence to make this recommendation. Transcutaneous bilirubinometry has emerged as a noninvasive, quick method to screen for neonatal hyperbilirubinemia, although refinement and validation of transcutaneous bilirubin nomograms are needed. Newer studies suggest that the combined use of a predischarge bilirubin and gestational age risk assessment offers a simple, objective, and accurate way to identify infants at risk for subsequent, severe hyperbilirubinemia.

SUMMARY

All newborns should be systematically assessed for risk of developing severe hyperbilirubinemia prior to hospital discharge. Although limited data exist to recommend its use universally, predischarge bilirubin screening should be considered given recent expert opinion. The role of transcutaneous bilirubinometry remains promising, although further research evaluating and validating its use in varied and diverse populations is imperative. Combined models of risk assessment may offer the best approach to identifying infants at risk for subsequent, severe hyperbilirubinemia.

Screening of infants for hyperbilirubinemia to prevent chronic bilirubin encephalopathy: US Preventive Services Task Force recommendation statement

DESCRIPTION

Recommendation on screening newborn infants, based on a recent supplemental review of a 2003 Agency for Healthcare Research and Quality evidence report on the effectiveness of various screening strategies for preventing the development of chronic bilirubin encephalopathy, performed at the request of the US Preventive Services Task Force (USPSTF). This topic has not been previously considered by the USPSTF.

METHODS

The USPSTF reviewed experimental and observational studies that included comparison groups. For harms associated with phototherapy, case reports or case series were also included.

CONCLUSION

The evidence is insufficient to assess the balance of benefits and harms of screening for hyperbilirubinemia to prevent chronic bilirubin encephalopathy (I statement).