Screening for Hyperbilirubinemia in Japanese Very Low Birthweight Infants Using Transcutaneous Bilirubinometry

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.

Skin color influences transcutaneous bilirubin measurements: a systematic in vitro evaluation

OBJECTIVE

Concerns have been raised about the effect of skin color on the accuracy of transcutaneous bilirubin (TcB) measurements, a widely used method for hyperbilirubinemia diagnosis in newborns. Literature is inconclusive, with both reported under- and overestimations of the TcB with increasing skin pigmentation. Therefore, the influence of skin color on TcB measurements was systematically evaluated in a controlled, in vitro setting.

METHODS

A bilirubin meter (JM-105) was evaluated on layered phantoms that mimic neonatal skin with varying dermal bilirubin concentrations (0-250 µmol/L) and varying epidermal melanosome volume fractions (0-40%; light-dark skin color).

RESULTS

TcB measurements were influenced by skin pigmentation. Larger mimicked melanosome volume fractions and higher bilirubin levels led to larger underestimations of the measured TcB, compared to an unpigmented epidermis. In the in vitro setting of this study, these underestimations amounted to 26-132 µmol/L at a TcB level of 250 µmol/L.

CONCLUSION

This in vitro study provides insight into the effect of skin color on TcB measurements: the TcB is underestimated as skin pigmentation increases and this effect becomes more pronounced at higher bilirubin levels. Our results highlight the need for improved TcB meter design and cautious interpretation of TcB readings on newborns with dark skin.

IMPACT

Key message: Skin color influences transcutaneous bilirubin measurements: the darker the skin, the larger the underestimation. What this study adds to existing literature: Existing literature is inconclusive regarding the influence of skin color on transcutaneous bilirubin measurements. This study systematically evaluates and clarifies the influence of skin color on transcutaneous bilirubin measurements in a controlled, in vitro setting.

IMPACT

This study aids to better interpret the measured TcB level in patients with varying skin colors, and is particularly important when using TcB meters on patients with dark skin colors.

Quantification of cephalocaudal progression of jaundice in preterm infants

BACKGROUND

The cephalocaudal progression (CCP) of neonatal jaundice is a well-known phenomenon, but quantitative information on CCP in preterm infants is absent. In this study, CCP was quantified in preterm infants as a function of postnatal age and body location.

METHODS

5.693 transcutaneous bilirubin (TcB) measurements were performed in 101 preterm infants from birth until postnatal day seven at five body locations (forehead, sternum, hipbone, tibia, ankle). Multi-level linear regression analysis was performed to evaluate the CCP as a function of body location and postnatal age. TcB measurements at all body locations and postnatal days were compared to total serum bilirubin (TSB) levels (N = 1.113).

RESULTS

The overall average change in ratio of TcB compared to forehead was for sternum +0.04 [95% CI -0.02;0.09]; hipbone +0.05 [0.00;0.01]; tibia -0.33 [-0.38;-0.27] and ankle -0.62 [-0.68;-0.57]. No effect modification of CCP by sex, gestational age, birthweight, phototherapy, and TSB was found. The TcB maximally underestimated the TSB at the ankle -79.5 µmol [-0.1;159.2].

CONCLUSIONS

CCP is present in preterm infants and is relatively stable over time. Since TcB measurements on the tibia and ankle underestimate TSB significantly, we advise to use only measurement locations cephalic from the tibia; i.e., hipbone, sternum, and forehead.

IMPACT

Cephalocaudal progression (CCP) of jaundice in preterm infants, assessed by transcutaneous bilirubin (TcB) measurements, is substantial and rather stable over postnatal day 0 to 7. To the best of our knowledge, this study is the first to investigate CCP of jaundice in preterm infants as a function of postnatal age in preterm infants. Our results demonstrate that TcB measurements at the tibia and ankle differ from the TSB beyond the clinically used TcB safety margins. We advise to perform TcB measurements only at locations cephalic from the tibia; i.e., hipbone, forehead, and sternum.

The Impact of Phototherapy on the Accuracy of Transcutaneous Bilirubin Measurements in Neonates: Optimal Measurement Site and Timing

Transcutaneous bilirubinometer devices are widely applied to assess neonatal hyperbilirubinemia. However, the optimal skin site and timing of transcutaneous bilirubin (TCB) measurements for the strongest correlation with total serum bilirubin (TSB) levels after phototherapy are still unclear. We conducted a retrospective observational study evaluating the correlation of TCB and TSB levels in neonates postphototherapy. The TCB measurements on the forehead and mid-sternum at 0 and 30 min postphototherapy were assessed by using a JM-103 bilirubinometer. Paired TCB and TSB measurements were assessed by Pearson correlation and Bland–Altman plots. We analyzed 40 neonates with 96 TSB and 384 TCB measurements. The TSB level correlated moderately with the forehead TCB level at 30 min postphototherapy (r = 0.65) and less strongly with the midsternum TCB level at 0 min postphototherapy (r = 0.52). The forehead at 30 min after cessation of phototherapy was the best time point and location of TCB measurement for the assessment of neonatal jaundice status. The reliability of TCB measurements varied across skin sites and durations after phototherapy. The effectiveness of TCB measurement to assess neonatal hyperbilirubinemia is much better on covered skin areas (foreheads) 30 min postphototherapy. The appropriate application of transcutaneous bilirubinometers could aid in clinical practice and avoid unnecessary management.

Transcutaneous Bilirubin Monitoring in Preterm Infants of 23 to 34 Weeks' Gestation

OBJECTIVE

 The study aimed to evaluate the validity of transcutaneous bilirubin (TcB) measurements at three sites in premature infants born at 23^0/7 to 34^6/7 weeks' gestational age (GA) compared with total serum bilirubin (TSB) measurements.

STUDY DESIGN

 A prospective study was conducted at Banner - University Medical Center Phoenix, where informed consent was obtained from the infant's parent or legally authorized representative. Cohort A was comprised of infants 23^0/7 to 28^6/7 weeks' GA and Cohort B contained subjects 29^0/7 to 34^6/7 weeks' GA. Baseline TSB measurements were collected at approximately 24 hours of life, as the standard of care and the TcB measurements were obtained from the sternum, interscapular, and buttock areas at approximately ± 30 minutes from collection of the TSB. Statistical analysis of measurements including sensitivity, specificity, positive, and negative predictive values, and the area under the receiver operator characteristic curve (AUROC) were performed.

RESULTS

 A total of 166 infants were included in the study population. Cohort A consisted of 41 subjects and Cohort B contained 125 subjects. The results showed that baseline TcB measurements from the interscapular area were the most sensitive and specific with TSB levels >5.0 mg/dL in Cohort A. Baseline TcB measurements from the sternum demonstrated greatest sensitivity and specificity when the TSB level was >8.0 mg/dL in Cohort B. In general, each of the three sites in both cohorts demonstrated excellent AUROCs and negative predictive values.

CONCLUSION

 The use of a TcB meter in preterm infants can be a reliable noninvasive screening tool for hyperbilirubinemia, and it may be beneficial in decreasing painful stimuli and iatrogenic blood loss when used as an adjunct to TSB monitoring.

KEY POINTS

· Interscapular TcB is sensitive/specific in 23 to 29 weeks' GA.. · Sternal TcB is sensitive/specific in 29 to 35 weeks' GA.. · TcB readings are reliable in preterm infants.. · TcB is reliable when serum bilirubin is >5.0 mg/dL..

Accuracy of enhanced transcutaneous bilirubinometry according to various measurement sites

Objective

The goal of the study was to provide missing data on the accuracy of enhanced transcutaneous bilirubinometry in a monoracial population of term neonates, considering three different measurement sites.

Material and Methods

Transcutaneous bilirubin was measured using the JM-105 device on the forehead, chest, and abdomen. Blood sampling for total serum bilirubin concentration has been performed within 10 minutes of transcutaneous measurements. Paired transcutaneous bilirubin and total serum bilirubin measurements were statistically analyzed.

Results

The study group consisted of 102 healthy term Slovak infants. The correlation between total serum bilirubin and transcutaneous bilirubin was significant (coefficient of determination R2: 0.9045 forehead, 0.8808 sternum, 0.8467 abdomen). Transcutaneous measurements underestimated serum bilirubin levels significantly when total serum bilirubin values were higher than 15 mg/dL, irrespective of the site of transcutaneous measurements. The lowest mean difference between total serum bilirubin and transcutaneous bilirubin was identified on the sternum (median: -1.1 mg/dL). The area under the curve was >0.97 and >0.93 for detecting total serum bilirubin levels >10 mg/dL and >13 mg/dL, respectively, for all measurement sites. Transcutaneous measurements on the forehead and sternum provided very high sensitivity, with the best performance at the forehead.

Conclusion

Transcutaneous bilirubinometry using an enhanced device is an accurate, sensitive, and convenient screening method in term Caucasian neonates. Transcutaneous bilirubin measurements on the forehead, sternum, and abdomen are reliable, with the best performance on the forehead. It is necessary to confirm higher transcutaneous bilirubin values with a total serum bilirubin measurement.

The forehead is a better site than the sternum to check transcutaneous bilirubin during phototherapy in sick infants

Background

To confirm the accuracy of transcutaneous bilirubin (TcB) in the neonatal intensive care unit both with and without phototherapy, and compare forehead and sternum as the TcB assessment site.

Methods

We simultaneously assessed the total serum bilirubin (TSB) and TcB at the forehead and sternum, using a JM-103 bilirubinometer. We analyzed the correlation between the TSB and TcB assessed at the forehead and sternum, with measurements classified as ‘without phototherapy’ (before phototherapy and > 24 hours after phototherapy discontinuation) and ‘with phototherapy’ (after 24 hours of phototherapy).

Results

There were 1,084 paired forehead and sternum TcB measurements, with the corresponding TSB measurement, from 384 infants. Their mean gestational age of 35.4 ± 3.2 weeks (62% were preterm) and a mean birth weight of 2434 ± 768 grams, and TSB was 6.61 ± 3.56 mg/dL. Without phototherapy, TcB values at the forehead and sternum were correlated well to the TSB value (r = 0.925 and 0.915, respectively). With phototherapy, TcB values at the forehead and sternum were significantly correlated with the TSB value, but TcB at the forehead (r = 0.751) was a better match to the TSB than was TcB at the sternum (r = 0.668). Additionally, Bland-Altman plots showed a greater degree of underestimation of the TSB by TcB at the sternum with phototherapy.

Conclusions

TcB was more accurate in infants not receiving phototherapy. During phototherapy, it is better to assess TcB at the forehead rather than at the sternum.

Ratio of cord blood bilirubin and albumin as predictors of neonatal hyperbilirubinaemia

AIM OF THE STUDY

To compare cord blood albumin (CBA) and cord blood bilirubin (CBB) at birth as predictors for development of neonatal hyperbilirubinaemia.

MATERIAL AND METHODS

CBA and CBB of 388 healthy term neonates born by lower segment caesarean section (LSCS) were determined at birth and transcutaneous bilirubin (TCB) was measured every 12 hours from birth until 7 days of life or development of hyperbilirubinaemia requiring phototherapy.

RESULTS

The cut-off value of CBB and CBA as obtained by the receiver operating characteristic (ROC) curve was 1.90 mg/dl and 3.17 g/dl respectively. The sensitivity, specificity and positive predictive value (PPV) for CBB were 97.4%, 40.6% and 71.09% while for CBA they were 40.8%, 34.8% and 48.41%. The cut-off value for CBB/CBA ratio was 0.719 as obtained by the ROC curve and was determined to have 97.4% sensitivity, 62.6% specificity and a PPV of 79.61%.

CONCLUSIONS

CBB/CBA is a better indicator compared to CBA and CBB alone for prediction of neonatal hyperbilirubinaemia.

Accuracy of Transcutaneous Bilirubin Versus Serum Bilirubin Measurement in Preterm Infants Receiving Phototherapy: A Systematic Review

BACKGROUND

Jaundice is a common condition among preterm infants in the neonatal intensive care unit (NICU). Total serum bilirubin (TSB) offers a gold standard tool for measurement, but blood sampling can be costly, time-consuming, and not without risks of infection and pain. Transcutaneous bilimeter (TcB) allows for noninvasive assessment of bilirubin. However, due to questions of accuracy the use of the TcB in preterm infants receiving phototherapy has not been widely adapted in the NICU.

PURPOSE

To systematically review studies that measure TcB versus TSB bilirubin in preterm infants who are receiving phototherapy.

METHODS

A systematic electronic search of databases (CINAHL, EMBASE, Cochrane, Medline, PubMed) was completed for English language publications. No date limitation was placed on the search. Inclusion criteria were based on preterm infants that were in the NICU receiving or had recently received phototherapy.

RESULTS

Nine studies of different quantitative study designs were reviewed. A good to strong correlation between TcB and TSB in preterm infants receiving phototherapy was demonstrated. There was a stronger correlation found in studies that examined TcB in unexposed skin areas during phototherapy.

IMPLICATIONS FOR PRACTICE

TcB may allow for a reduction in blood sampling, which would reduce painful procedures, reduce the risk of infection and anemia resulting from repeated blood sampling. It also acts as a more time and cost-efficient measurement tool.

IMPLICATIONS FOR RESEARCH

Larger scaled quantitative studies on the accuracy of TcB in preterm infants receiving phototherapy are needed to provide more evidence-based data and guide clinical practice on this topic.

Comparison of transcutaneous and serum bilirubin before, under, and after phototherapy in term and late-preterm infants

This study aimed to determine the correlation of transcutaneous bilirubin (TcB) with total serum bilirubin (TSB) in infants receiving phototherapy and the accuracy of TcB for deciding the time to discontinue phototherapy. Paired TcB and TSB levels were assessed in 52 term and 56 late-preterm infants receiving phototherapy. TcB was measured in the unexposed skin of the middle forehead using a noninvasive bilirubin analyzer, BiliChek. TSB was measured every morning, and TcB was measured 2 hours after TSB measurements. Bland-Altman plots, linear regression, multivariate pair wise correlation, and receiver operating characteristic curve (ROC) analyses were performed. Bland-Altman plots before, under, and 24 hours after phototherapy in term and late-preterm infants revealed that TcB and TSB have higher consistency. TcB and TSB showed positive linear correlation before, under, and after phototherapy in both infant groups. In the multivariate pair wise correlations, differences between TcB and TSB were negatively correlated with phototherapy duration in term (correlation coefficient = -0.233, P value = .001) and late-preterm (correlation coefficient = -0.198, P value = .002) infants. Cutoff levels of TcB for discontinuing phototherapy based on the ROC analysis were 13.8 (sensitivity of 90%, specificity of 84%, area under the curve [AUC] 0.94) and 11.8 mg/dL (sensitivity of 84%, specificity of 88%, AUC 0.92) in term and late-preterm infants, respectively. TcB and TSB before, under, and after phototherapy in both term and late-preterm infants showed good correlation and higher consistency with jaundice. To reduce repetitive blood sampling for TSB, TcB measurement may be a reliable method for term and late-preterm infants undergoing phototherapy.

Comparison of Diagnostic Accuracy of Different Sites for Transcutaneous Bilirubin Measurement in Early Preterm Infants

OBJECTIVE

To evaluate correlation of transcutaneous bilirubin (TcB) measured at different body sites with serum total bilirubin (TSB) in early preterm infants.

METHODS

This hospital based prospective comparative study was carried out in the Department of Pediatrics, SMS Medical College, Jaipur between April 2015 to March 2016. Early preterm infants with gestational age ≤ 34 weeks in whom clinical jaundice was significant mandating TSB measurement were included in the study. Study subjects who met the inclusion criteria were chosen consecutively. Neonates in whom phototherapy was already initiated and those with poor perfusion (capillary refill time > 3 s) were excluded from the study. All the measurements were carried out within first postnatal week. Transcutaneous bilirubin was measured from three sites: forehead, sternum and interscapular region and within 15 min of TcB measurement, blood samples were taken and serum bilirubin level was calculated.

RESULTS

Correlation coefficients of transcutaneous bilirubin measured from forehead, sternum and interscapular sites were 0.82, 0.84 and 0.86 respectively. TcB measured from all the three sites correlated significantly with serum bilirubin (p < 0.001), but the correlation was best at interscapular site. Sensitivity, specificity and false negative rates were calculated with respect to starting phototherapy. Interscapular site had the highest sensitivity and lowest false negative rate (87.6 and 12.4% respectively) as compared to forehead (79.2 and 20.8% respectively) and sternum (87.1 and 12.9% respectively).

CONCLUSIONS

Transcutaneous bilirubin measurement is an acceptable method for identification of hyperbilirubinemia requiring treatment in early preterm newborns. The authors recommend interscapular region as a reliable site in infants of gestational age ≤34 wk for measuring transcutaneous bilirubin.

Comparison of Transcutaneous and Serum Bilirubin Measurements in Neonates 30 to 34 Weeks' Gestation Before, During, and After Phototherapy

BACKGROUND

The use of noninvasive, transcutaneous bilirubin monitoring (TcB) as a jaundice screen in full-term infants is well established; however, there is a paucity of research evaluating the use of TcB in premature infants.

PURPOSE

To compare agreement and consistency of transcutaneous and serum bilirubin measurements in a multiracial premature infant population ranging from 30 to 34(Equation is included in full-text article.)weeks' gestation before, during, and after phototherapy.

METHODS

Forty-five neonates, 30 to 34(Equation is included in full-text article.)weeks' gestation, were enrolled in this prospective, correlational study over a 12-month period. One set of paired transcutaneous and serum bilirubin measurements, per neonate, was obtained before phototherapy, during therapy, and after phototherapy. Exclusion criteria included neonates with positive direct coombs test or evidence of hemolytic disease, major congenital anomalies, hydrops fetalis, and those not expected to survive.

RESULTS

There was a strong, positive correlation between TcB and total serum monitoring (TSB) measurements obtained pretherapy (r = 0.797, P < .001). A moderate correlation was noted between TcB and TSB measurements obtained during therapy (r = 0.588, P < .001). A strong correlation was noted between TcB and TSB measurements obtained posttherapy (r = 0.869, P < .001). There were no significant differences between paired samples across time (F = 0.891, P = .41, partial η = 0.01). The TSB measurements were consistently lower than TcB pretherapy, during, and posttherapy.

IMPLICATIONS FOR PRACTICE

The TcB measurements provide a reliable estimation, generally within 2 to 3 mg/dL of TSB levels, in premature infants 30 to 34(Equation is included in full-text article.)weeks' gestation.

IMPLICATIONS FOR RESEARCH

Investigation of consumption of time and nursing personnel required to perform TcB testing, compared with TSB testing, is indicated. Cost analyses comparing TcB-driven screening protocols and interval TSB measurements, among premature infants, are indicated. As newer generations of TcB devices are approved for use, additional studies using mixed-race populations of premature infants will be necessary to continue to evaluate the reliability and validity of this screening tool within the everyday neonatal intensive care unit.

Evaluation of BiliCare™ transcutaneous bilirubin device in Japanese newborns

BACKGROUND

Non-invasive transcutaneous bilirubin (TcB) monitoring has been widely used to screen for hyperbilirubinemia. TcB measured using the recently developed BiliCare™ system, however, has not been fully evaluated.

METHODS

One hundred and seven TcB measurements were obtained from 82 Japanese newborns ≥35 weeks' gestational age within 2 weeks after birth. Measurements were taken at the scaphoid fossa, conchal cavity, and lobe of the ear using BiliCare. BiliCare TcB were compared with total serum bilirubin (TB) and TcB obtained using another bilirubinometer (JM-105™).

RESULTS

Transcutaneous bilirubin measured at all three sites significantly correlated with TB (r = 0.91, 0.93, and 0.93 at the scaphoid fossa, conchal cavity, and lobe, respectively). The mean differences were 0.1, -0.3, and 3.6 at the scaphoid fossa, conchal cavity, and lobe, respectively. BiliCare TcB at the scaphoid fossa significantly correlated with that using the JM-105 (r = 0.91). The mean difference was 0.0. BiliCare, however, produced a significantly higher and lower TcB than the JM-105 for TB <7 and ≥15 mg/dL, respectively.

CONCLUSIONS

Transcutaneous bilirubin measurements taken at the scaphoid fossa or conchal cavity using BiliCare were more reliable than those at the earlobe. BiliCare TcB differed from those of the JM-105, for TB <7 or ≥15 mg/dL.