A Simpler Prediction Rule for Rebound Hyperbilirubinemia

Bilirubin measurements in neonates: uniform neonatal treatment can only be achieved by improved standardization

Measurement of total bilirubin (TBil) concentration in serum is the gold standard approach for diagnosing neonatal unconjugated hyperbilirubinemia. It is of utmost importance that the measured TBil concentration is sufficiently accurate to prevent under treatment, unnecessary escalation of care, or overtreatment. However, it is widely recognized that TBil measurements urgently require improvement in neonatal clinical chemistry. External quality assessment (EQA) programs for TBil assess for differences between laboratories and provide supporting evidence of significant differences between various methods, manufacturers and measurement platforms. At the same time, many countries have adopted or only slightly adapted the neonatal hyperbilirubinemia management guidelines from the USA or UK, often without addressing differences in the methodology of TBil measurements. In this report, we provide an overview of the components of bilirubin that are measured by laboratory platforms, the availability of current reference measurement procedures and reference materials, and the role of EQA surveys in this context. Furthermore, the current status of agreement in neonatal bilirubin against clinical decision thresholds is reviewed. We advocate for enhancements in accuracy and comparability of neonatal TBil measurements, propose a path forward to accomplish this, and reflect on the position of the International Federation for Clinical Chemistry and Laboratory Medicine (IFCC) Working Group Neonatal Bilirubin (WG-NB) in this matter.

Clinical study to determine the predictability of significant rebound hyperbilirubinemia in neonates after phototherapy and conditions likely to be associated with it: Prospective observational study in a teaching hospital in Eastern India

Aim

Neonatal hyperbilirubinemia is defined as yellowish discoloration of the skin, conjunctive, and sclera from the elevated serum or plasma bilirubin in the newborn. The standard of care for the management of neonatal hyperbilirubinemia is phototherapy to prevent long-term neurological sequelae. The aim of this study was to ascertain the predictability of significant rebound hyperbilirubinemia (SRH) in neonates after phototherapy and the factors associated with it.

Materials and Methods

Neonates ≥ 35 weeks of gestation, who received treatment for hyperbilirubinemia and admitted in our hospital from 15th of March 2019 to 15th of September 2020 were enrolled after taking parental consent. SRH was defined as bilirubin levels crossing the treatment threshold within 72 hours of phototherapy termination. Logistic regression analysis was used to identify the predictability of SRH.

Results

Out of 400 neonates treated with phototherapy, 10% developed SRH. Prematurity (Gestational age < 37 weeks), low birth weight (Birth weight < 2000 gram), ABO and Rh incompatibility, Glucose-6-phophate dehydrogenase deficiency (G6PD) deficiency, sepsis, and longer duration of primary phototherapy were found to be significantly associated with rebound hyperbilirubinemia. The probability of SRH increases for all American Academy of Paediatrics (AAP) risk categories as the gestational age decreases and total serum bilirubin at the stoppage of phototherapy increases.

Conclusions

The presence of risk factors should be taken into account while planning discharge and follow-up of neonates admitted for neonatal hyperbilirubinemia to prevent long-term complication of bilirubin neurotoxicity.

Updated Clinical Practice Guidelines for Management of Hyperbilirubinemia in Infants Born at 35 Weeks or More Gestation

Given the prevalence of jaundice in newborns, and the consequences of untreated hyperbilirubinemia, the long-awaited revised clinical practice guidelines for hyperbilirubinemia were finally released in August 2022 by the American Academy of Pediatrics as an update to the 2004 guidelines on the same topic. As new evidence and data become available, it is important for pediatricians and neonatologists to re-assess their clinical decision-making over time to ensure that patients are receiving the best care possible. With improvements in medical equipment and medical technology, and growing concerns about the overtreatment of hyperbilirubinemia, the newest clinical practice guidelines attempt to tackle the prevention, risk assessment, monitoring, and treatment of hyperbilirubinemia with these things in mind. [Pediatr Ann. 2023;52(12):e436-e439.].

Risk factors for readmission for hyperbilirubinemia in neonates with ABO hemolytic disease: a single-center retrospective cohort study

OBJECTIVE

ABO hemolytic disease of the newborn (ABO-HDN) is a major risk factor for severe hyperbilirubinemia, a common readmission reason for newborns. In this study, we aimed to assess the risk factors for readmission associated with hyperbilirubinemia in neonates with ABO-HDN.

METHODS

A retrospective cohort study was conducted including newborns with gestational age ≥35 weeks and ABO-HDN in 2018. Among 291 newborns, 36 were readmitted for hyperbilirubinemia and defined as the readmission group. The remaining 255 cases were used as a control group. We then performed between-group comparisons of clinical conditions associated with hyperbilirubinemia. Logistic regression was used to select risk predictors of readmission associated with hyperbilirubinemia due to ABO-HDN.

RESULTS

Baseline characteristics were similar between both groups (p > .05, respectively). However, total serum bilirubin (TSB) before initiating phototherapy was significantly higher in the readmission group when compared with that in the control group at 0-24 h, 24-48 h, and 48-72 h (183.70 µmol/L [interquartile range (IQR) 161.18-196.48] vs. 150.35 µmol/L [IQR 131.73-175.38], p = .005; 229.90 µmol/L [IQR 212.45-284.30] vs. 212.50 µmol/L [IQR 197.85-230.28], p = .026; 268.10 µmol/L [IQR 257.70-279.05] vs. 249.50 µmol/L [IQR 236.80-268.70], p = .045, respectively). The age of initiation of phototherapy in the readmission group was significantly lower than that in control group (30.0 h [IQR 18.0-49.00] vs. 42.0 h [IQR 23.0-61.0], p = .012). The rate of rebound hyperbilirubinemia after the first phototherapy treatment was significantly higher in the readmission group compared to that in the control group (9 [25%] vs. 13 [5.1%], p = .000), and the rate of positive direct antiglobulin testing was significantly higher than that in control group (17 [47.2%] vs. 74 [29.0%], p = .027). Logistic regression analysis showed that the age of initiation of photography, TSB level before the first phototherapy, and rebound hyperbilirubinemia after first phototherapy were independent risk factors for readmission in newborns with hyperbilirubinemia associated with ABO-HDN.

CONCLUSIONS

Earlier age of phototherapy initiation, higher TSB levels at the time of initiating phototherapy and rebound hyperbilirubinemia after the first phototherapy treatment may increase the risk of readmission for hyperbilirubinemia in neonates with ABO-HDN. These factors should be considered in discharge planning and follow-up for newborns with ABO-HDN associated hyperbilirubinemia.

Readmission Reduction for Hyperbilirubinemia in Infants ≥ 35 Weeks Estimated Gestational Age Using a Standardized Protocol

BACKGROUND

Most newborns experience hyperbilirubinemia. Monitoring and treatment must be balanced with the risk of unintended harm, including readmission to the birth hospital. From January 2019 to April 2021, the average rate of inborn readmission for all causes was 2.09% at the study hospital; hyperbilirubinemia accounted for 91% of these readmissions. The aim of this project was to decrease readmission rate for hyperbilirubinemia by 60% within eight months of protocol implementation.

METHODS

The Lean system of quality improvement was used to assess root causes and implement countermeasures. A hyperbilirubinemia protocol was developed, and phototherapy equipment was upgraded. Monthly readmission rates were the main outcome measure. Process measures included hour of life for initial transcutaneous bilirubin measurement. Balance measures included number of serum bilirubin labs obtained per 100 infants, percentage treated with phototherapy, mean length of phototherapy treatment, and length of hospital stay. Statistical process control charts were used to measure changes in quality over time.

RESULTS

Baseline data showed a monthly readmission rate for hyperbilirubinemia of 1.9%. Following countermeasure implementation, there was a clinically significant downward shift in the monthly readmission rate to 0.64%, representing a 66% decrease from baseline.

CONCLUSION

Implementation of the project protocol was associated with a clinically significant decrease in readmissions for hyperbilirubinemia with no concurrent clinically significant changes in the number of labs drawn, number of infants started on phototherapy, or average length of hospital stay. For military treatment facilities or institutions with similar staffing models, this protocol may offer a model for improvement.

Increasing utilisation of a rebound hyperbilirubinaemia calculator in two newborn nurseries

Neonatal hyperbilirubinaemia requiring phototherapy treatment is a common problem impacting the length of hospital stay and rates of hospital readmission. Previous guidelines included guidance for initiating phototherapy treatment but not for discontinuing phototherapy treatment during initial newborn admission.In response to dissatisfaction from trainees, staff and families regarding the variable approach to discontinuing phototherapy among attending nursery providers, we used quality improvement methodologies to increase utilisation of a rebound hyperbilirubinaemia calculator as a more consistent method for guiding the timing of phototherapy discontinuation. The aim was to increase utilisation of the rebound hyperbilirubinaemia calculator for newborns treated with phototherapy in two newborn nurseries to >90% within 2 years.Sequential interventions focused on increasing provider awareness of the rebound hyperbilirubinaemia calculator and making the calculator simple to access and use.At the university medical centre nursery, the use of the calculator increased from 8.7% to 100%, exceeding the project goal. In the community hospital nursery, there was a statistically significant increase in the rate of utilisation from 3.7% to 79.4%, but this fell slightly below the goal of >90%.Electronic Health Record integration, along with education and addition of prompts to providers, increased utilisation of a rebound hyperbilirubinaemia calculator as a consistent approach for guiding decisions about discontinuing phototherapy treatment in newborns.

[Interpretation of the 2022 American Academy of Pediatrics guidelines for the management of hyperbilirubinemia in newborn infants]

The American Academy of Pediatrics updated the guidelines for the management of hyperbilirubinemia in the newborn infants with a gestational age of ≥35 weeks in September 2022. Based on the evidence over the past 18 years, the guidelines are updated from the aspects of the prevention, risk assessment, intervention, and follow-up of hyperbilirubinemia in the newborn infants with a gestational age of ≥35 weeks. This article gives an interpretation of the key points in the guidelines, so as to safely reduce the risk of bilirubin encephalopathy and unnecessary intervention.

Higher ETCOc predicts longer phototherapy treatment in neonatal hyperbilirubinemia

Objective

This study aimed to evaluate the predictive performance of end-tidal carbon monoxide corrected to ambient carbon monoxide (ETCOc) values phototherapy in neonates with significant hyperbilirubinemia.

Methods

A prospective study was conducted on neonates with significant hyperbilirubinemia who received phototherapy between 3 and 7 days of life. The breath ETCOc and serum total bilirubin of the recruited infants were measured on admission.

Results

The mean ETCOc at admission in 103 neonates with significant hyperbilirubinemia was 1.70 ppm. The neonates were categorized into two groups: phototherapy duration ≤72 h (n = 87) and >72 h (n = 16) groups. Infants who received phototherapy for >72 h had significantly higher ETCOc (2.45 vs. 1.60, P = 0.001). The cutoff value of ETCOc on admission for predicting longer phototherapy duration was 2.4 ppm, with a sensitivity of 62.5% and specificity of 88.5%, yielding a 50% positive predictive value and a 92.7% negative predictive value.

Conclusion

ETCOc on admission can help predict the duration of phototherapy in neonates with hyperbilirubinemia, facilitate clinicians to judge disease severity, and make clinical communication easier and more efficient.

Prediction Model for Croup Admission Need

OBJECTIVES

This study aims to generate a predictive model stratifying the probability of requiring hospitalization and inpatient respiratory intervention for croup patients presenting to the emergency department (ED), and secondarily to compare the model's performance with that of ED providers.

METHODS

Retrospective data was collected on croup patients presenting to the EDs of 2 pediatric and 1 community hospital from 2019 to 2020, including demographics, preexisting conditions, and history of croup. The ED length of stay, previous dexamethasone administration, time to ED dexamethasone, number of ED racemic epinephrine doses, viral testing, and ED revisits were also recorded. Westley croup scores were derived at ED presentation and final disposition. For admitted patients, any respiratory interventions were recorded. Admission need was defined as either admitted and required an inpatient intervention or not admitted with ED revisit. A prediction model for admission need was fit using L1-penalized logistic regression.

RESULTS

We included 2951 patients in the study, 68 (2.3%) of which needed admission. The model's predictors were disposition Westley croup scores, number of ED racemic epinephrine doses, previous dexamethasone administration, and history of intubation. The model's sensitivity was 66%, specificity was 91%, positive predictive value was 15%, and negative predictive value was 99%. ED providers' performance had a sensitivity of 72%, a specificity of 94%, a positive predictive value of 23%, and a negative predictive value of 99%.

CONCLUSIONS

The croup admission need predictive model appears to support clinical decision making in the ED, with the potential to improve decision making when pediatric expertise is limited.

Hospital Readmission Among Late Preterm Infants: New Insights and Remaining Questions

Late preterm infants (LPIs), those born at 34 to 36 6/7 weeks' gestation, account for the majority of preterm births (73%).1 Given their physiologic immaturity, LPIs are at increased risk of respiratory distress, hyperbilirubinemia, hypoglycemia, and other complications in the neonatal period, and are at increased risk of hospital readmission in the first month of life.2 As Amsalu and colleagues describe in this month's issue of Hospital Pediatrics,3 identification of a predictive model to differentiate LPI at higher risk of complications would help inform tailored discharge plans and prevent readmissions.

Risk Factors and Predictors of Rebound Hyperbilirubinemia in a Term and Late-Preterm Infant with Hemolysis

OBJECTIVE

This study aimed to assess the incidence and predictors of rebound in term and late-preterm infants with hemolytic hyperbilirubinemia postphototherapy.

STUDY DESIGN

A 4-year retrospective data analysis of neonates with hemolytic indirect hyperbilirubinemia admitted to the neonatal intensive care unit (NICU) of Medina Maternity and Children's Hospital was conducted. Bilirubin rebound was defined as the return of total serum bilirubin (TSB) to phototherapy threshold within 72 hours of postphototherapy.

RESULTS

Of 386 identified neonates; 44 (11%) experienced rebound. Neonates in the rebound group demonstrated significantly higher levels of peak TSB, TSB at discontinuation of phototherapy, and lower value of relative TSB (difference between TSB at phototherapy termination and the American Academy of Pediatrics [AAP] threshold for phototherapy at concurrent age) compared with nonrebound group (p-value: <0.001, <0.001, and 0.007, respectively). Lower value of relative TSB at stoppage of phototherapy was the single independent predictor for rebound hyperbilirubinemia by mutivariate regression (p < 0.001). A cut-off value for relative TSB at stoppage of phototherapy of 190 µmol/L had 98% sensitivity and 32% specificity to predict rebound hyperbilirubinemia.

CONCLUSION

Relative TSB at phototherapy termination is the best predictor for postphototherapy rebound hyperbilirubinemia in neonates with hemolytic etiology.

KEY POINTS

· 11% of neonates showed postphototherapy rebound.. · The relative TSB at stoppage of phototherapy is the best predictor for rebound hyperbilirubinemia.. · The first cohort to assess rebound in neonates with hemolysis..

Validation of published rebound hyperbilirubinemia risk prediction scores during birth hospitalization after initial phototherapy: a retrospective chart review

BACKGROUND

Hyperbilirubinemia commonly affects newborns and may lead to neurotoxicity if untreated. Neonates can experience rebound hyperbilirubinemia (RHB), defined as elevated bilirubin levels requiring re-initiation of treatment. Although studies have formulated risk prediction scores, they lack external validation. In this study, we examine the discrimination and calibration performance of risk prediction scores for RHB, to provide external validation.

METHODS

We reviewed charts of neonates born ≥35 weeks of gestation between January 2015 and December 2019 receiving phototherapy at birth hospitalization. We plotted predicted probabilities against observed outcome proportions to assess model calibration and evaluated discrimination using area under the receiver operating characteristic (AUROC) curves. Odds ratios (ORs) were estimated to evaluate variables associated with RHB.

RESULTS

Of the 271 infants identified, 24% developed RHB. Two- and three-variable prediction scores had lower discrimination in our cohort with AUROC of 0.662 (95% CI 0.590-0.735) and 0.691 (95% CI, 0.619-0.763) compared to 0.876 (95% CI 0.854-0.899) and 0.881 (95% CI 0.859-0.903), respectively, in the published studies. Estimated ORs confirm associations between RHB and variables included in prediction scores.

CONCLUSIONS

Current prediction models for RHB have unclear clinical utility in our patient population. Additional studies are required to further validate these scores.

IMPACT

Describes performance characteristics of two- and three-variable risk prediction scores that lack external validation beyond the initial study cohort. Our findings suggest unclear clinical utility in our clinical population of neonates during birth hospitalization, with lower performance of these prediction scores than observed in the derivation cohort. Odds ratios estimated by logistic regression in our study cohort provide further evidence that variables in published risk prediction scores are associated with rebound hyperbilirubinemia. Further studies are required to externally validate these risk prediction scores and to assess their generalizability.

Predictive Models for Neonatal Follow-Up Serum Bilirubin: Model Development and Validation

Background

Hyperbilirubinemia affects many newborn infants and, if not treated appropriately, can lead to irreversible brain injury.

Objective

This study aims to develop predictive models of follow-up total serum bilirubin measurement and to compare their accuracy with that of clinician predictions.

Methods

Subjects were patients born between June 2015 and June 2019 at 4 hospitals in Massachusetts. The prediction target was a follow-up total serum bilirubin measurement obtained <72 hours after a previous measurement. Birth before versus after February 2019 was used to generate a training set (27,428 target measurements) and a held-out test set (3320 measurements), respectively. Multiple supervised learning models were trained. To further assess model performance, predictions on the held-out test set were also compared with corresponding predictions from clinicians.

Results

The best predictive accuracy on the held-out test set was obtained with the multilayer perceptron (ie, neural network, mean absolute error [MAE] 1.05 mg/dL) and Xgboost (MAE 1.04 mg/dL) models. A limited number of predictors were sufficient for constructing models with the best performance and avoiding overfitting: current bilirubin measurement, last rate of rise, proportion of time under phototherapy, time to next measurement, gestational age at birth, current age, and fractional weight change from birth. Clinicians made a total of 210 prospective predictions. The neural network model accuracy on this subset of predictions had an MAE of 1.06 mg/dL compared with clinician predictions with an MAE of 1.38 mg/dL (P<.0001). In babies born at 35 weeks of gestation or later, this approach was also applied to predict the binary outcome of subsequently exceeding consensus guidelines for phototherapy initiation and achieved an area under the receiver operator characteristic curve of 0.94 (95% CI 0.91 to 0.97).

Conclusions

This study developed predictive models for neonatal follow-up total serum bilirubin measurements that outperform clinicians. This may be the first report of models that predict specific bilirubin values, are not limited to near-term patients without risk factors, and take into account the effect of phototherapy.