Accuracy of neonatal transcutaneous bilirubin measurement in the outpatient setting

Transcutaneous Bilirubin Accuracy Before, During, and After Phototherapy: A Meta-Analysis

CONTEXT

Transcutaneous bilirubinometry (TcB) is used as a valid screening to identify neonates requiring measurement of total serum bilirubin (TSB) before phototherapy. Its use during and after phototherapy is not advised yet because of unknown reliability.

OBJECTIVES

To determine the agreement of TcB and TSB measurements before, during, and after phototherapy.

DATA SOURCES

PubMed Medline, Cochrane Library, and references of eligible studies were searched.

STUDY SELECTION

Prospective and retrospective cohort and cross-sectional studies reporting Bland-Altman statistics of paired TcB and TSB measurements in term and preterm newborns.

DATA EXTRACTION

Meta-analysis was performed using the Mantel-Haenszel weighted approach. The agreement between TcB and TSB in μmol/L was described by pooled mean differences (MDs) and limits of agreement (LoA).

RESULTS

Fifty-four studies were included. The pooled MD before phototherapy is 2.5 μmol/L (LoA -38.3 to 43.3). The pooled MD during phototherapy is -0.3 μmol/L (LoA -34.8 to 34.2) on covered skin and -28.6 μmol/L (LoA -105.7 to 48.5) on uncovered skin. The pooled MD after phototherapy is -34.3 μmol/L (LoA -86.7 to 18.1) on covered skin and -21.1 μmol/L (LoA -88.6 to 46.4) on uncovered skin. Subgroup analysis revealed the best agreement at the forehead. We did not find any difference in agreement between term and preterm neonates.

LIMITATIONS

Language restriction.

CONCLUSIONS

TcB measurements before and during phototherapy on covered skin show good agreement compared with TSB in term and preterm newborns. More studies are needed to evaluate the accuracy after phototherapy.

Transcutaneous bilirubinometry versus total serum bilirubin measurement for newborns

BACKGROUND

Jaundice is a very common condition in newborns, affecting up to 60% of term newborns and 80% of preterm newborns in the first week of life. Jaundice is caused by increased bilirubin in the blood from the breakdown of red blood cells. The gold standard for measuring bilirubin levels is obtaining a blood sample and processing it in a laboratory. However, noninvasive transcutaneous bilirubin (TcB) measurement devices are widely available and used in many settings to estimate total serum bilirubin (TSB) levels.

OBJECTIVES

To determine the diagnostic accuracy of transcutaneous bilirubin measurement for detecting hyperbilirubinaemia in newborns.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL and trial registries up to 18 August 2022. We also checked the reference lists of all included studies and relevant systematic reviews for other potentially eligible studies.

SELECTION CRITERIA

We included cross-sectional and prospective cohort studies that evaluated the accuracy of any TcB device compared to TSB measurement in term or preterm newborn infants (0 to 28 days postnatal age). All included studies provided sufficient data and information to create a 2 × 2 table for the calculation of measures of diagnostic accuracy, including sensitivities and specificities. We excluded studies that only reported correlation coefficients.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the eligibility criteria to all citations from the search and extracted data from the included studies using a standard data extraction form. We summarised the available results narratively and, where possible, we combined study data in a meta-analysis.

MAIN RESULTS

We included 23 studies, involving 5058 participants. All studies had low risk of bias as measured by the QUADAS 2 tool. The studies were conducted in different countries and settings, included newborns of different gestational and postnatal ages, compared various TcB devices (including the JM 101, JM 102, JM 103, BiliChek, Bilitest and JH20-1C) and used different cutoff values for a positive result. In most studies, the TcB measurement was taken from the forehead, sternum, or both. The sensitivity of various TcB cutoff values to detect significant hyperbilirubinaemia ranged from 74% to 100%, and specificity ranged from 18% to 89%.

AUTHORS' CONCLUSIONS

The high sensitivity of TcB to detect hyperbilirubinaemia suggests that TcB devices are reliable screening tests for ruling out hyperbilirubinaemia in newborn infants. Positive test results would require confirmation through serum bilirubin measurement.

The accuracy of transcutaneous bilirubin to identify hyperbilirubinemia in jaundiced neonates

OBJECTIVE

To compare transcutaneous bilirubin (TcB) to total serum bilirubin (TSB) in jaundiced neonates by using a JM-103 bilirubinometer.

METHODS

We conducted a retrospective study in jaundiced infants ≥35 weeks' gestation. Infants' and maternal information, TcB measurements, and TSB levels were collected. The correlation and consistency between TcB and TSB were analyzed by Pearson's correlation analysis and the Bland-Altman plot. Multivariate regression analysis was used to identify characteristics associated with the difference between TcB and TSB, underestimation by TcB and overestimation by TcB.

RESULTS

A total of 787 paired samples were collected. There was a strong correlation between TcB and TSB with a Pearson correlation coefficient of 0.708 (p < .001). In preterm infants, outpatients and infants with high TSB levels, the TcB measurements were less precise. The TcB-TSB difference was significantly associated with gender, maternal hypertension disease, ABO hemolytic disease, and outpatient setting (p < .05). Only the outpatient setting had statistical significance in the underestimation of TSB ≥2 mg/dL.

CONCLUSIONS

Generally, TcB by a JM-103 bilirubinometer had a good correlation and consistency with the TSB values. However, small for gestational age, postnatal age of hour, ABO hemolytic disease, and outpatient setting may lead to inconsistencies between the TcB and TSB.

Reducing Outpatient Infant Blood Draws with Transcutaneous Measurement of Bilirubin

Introduction:

Newborn jaundice is a common outpatient problem. Transcutaneous bilirubin (TcB) measurements correlate well with total serum bilirubin (SB) measurements below 15 mg/dl and are efficient and noninvasive. Some concern exists that TcB measurement may subsequently lead to an increase in the number of SB measurements performed in the outpatient setting. We aimed to implement the use of a TcB device in an outpatient clinic. By doing so, we sought to increase the number of newborns screened solely by TcB as opposed to SB, by 30%, within 12 months.

Methods:

We conducted plan-do-study-act cycles with targeted interventions to promote the use of TcB in an outpatient clinic for eligible newborns older than 35 weeks gestational age, aged 1–20 days, and without a history of transfusion, phototherapy, extensive bruising, or risk of hemolysis. We used statistical process control methods to measure proportions of newborns evaluated with TcB (run chart) and patients-between SB measurements (G-chart) over time in the outpatient clinic.

Results:

We collected preintervention data for 18-months and intervention data for 12 months. For newborns attending the outpatient clinic, the proportion of TcB measurements increased after implementation of the use of TcB measurement. There was an increase in patients-between SB measurements. At project inception, SB was drawn for every 8 eligible patients. By the end of the project, there were 98 eligible newborns between instances of SB testing.

Conclusion:

Implementation of a quality-improvement initiative to measure TcB in the outpatient clinic was feasible and reduced the number of SB tests.

Accuracy of the Bilicare™ transcutaneous bilirubinometer as the predischarge screening tool for significant hyperbilirubinemia in healthy term and late preterm neonates

Background: The Bilicare™ is a new device that measures transcutaneous bilirubin (TcB) level at the ear pinna. There are only few studies which have evaluated its accuracy in clinical practice.Objective: This study aims to determine the accuracy of Bilicare™ as a predischarge screening tool in late preterm and term neonates and to define the optimal cutoff point for determining the need to measure total serum bilirubin (TSB).Methods: The 35 weeks' gestation or more and healthy neonates who underwent predischarge TSB measurement were enrolled. Bilicare™ TcB was measured within 30 minutes of blood sampling. Paired TcB and TSB data were analyzed.Results: We collected 214 paired samples. Mean age (SD) at TcB measurement was 57.17 (7.47) hours. Mean TSB (SD) was 9.79 (2.83) mg/dL. TcB showed a significant correlation with TSB (r = 0.84, r² = 0.7). The mean difference (SD) between TcB and TSB was 0.7 (0.21) mg/dL (95%CI 0.49-0.91). TcB tended to overestimate TSB level at the TSB values of <12 mg/dL but underestimate at the higher TSB level. The accuracy of using TcB values to detect neonates who required phototherapy was 92.5%. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 78.3, 94.2, 62.1, and 97.3%, respectively. If TcB +3 mg/dL was applied as a cutoff point, the sensitivity, specificity, PPV, and NPV were 100, 53.9, 20.7, and 100%, respectively.Conclusions: Bilicare™ TcB and TSB measurements were well correlated. The TcB level +3 mg/dL could detect all neonates who had significant hyperbilirubinemia requiring phototherapy during their birth hospitalization.

Defining the limitations of transcutaneous bilirubin measurement in late preterm newborns

OBJECTIVE

The objective of this study is to determine the impact of postnatal age on the bias between transcutaneous (TcB) and total serum bilirubin (TSB), and evaluate a TcB screening protocol.

STUDY DESIGN

Preterm and term infants had paired TcB and TSB performed on days 1 to 3 of life; a subset of preterm infants had measurements on days 4 to 7. Sensitivity and specificity of TcB (plotted on an age-specific TSB nomogram) for prediction of high-intermediate (HIR) or high-risk TSB were calculated.

RESULTS

Median TcB bias was 2.6 and 2.5 mg dl^-1 for term and preterm infants in the first 3 days of life, respectively. However, median bias was 2.2 mg dl^-1 for preterm infants at 4 to 7 days of life. TcB in preterm infants predicted HIR or high-risk TSB with 94% sensitivity and 56% specificity.

CONCLUSION

TcB screening protocols developed for term infants can be used for late preterm infants in the first 3 days of life.