Transcutaneous Bilirubin Meter Research Articles

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

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. 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). 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. 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. 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. 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.

Demystifying non-invasive approaches for screening jaundice in low resource settings: a review.

All national and international pediatric guidelines universally prescribe meticulous bilirubin screening for neonates as a critical measure to mitigate the incidence of acute bilirubin encephalopathy (ABE) and Kernicterus. The prevailing gold standard for jaundice detection in neonates necessitates invasive blood collection, followed by subsequent biochemical testing. While the invasive procedure provides dependable bilirubin measurements and continues to be the sole gold standard diagnostic method for assessing bilirubin concentration. There exists a pressing need to innovate non-invasive screening tools that alleviate the sampling stress endured by newborns, mitigate iatrogenic anemia, and expedite the turnaround time for obtaining results. The exploration of non-invasive modalities for bilirubin measurements is gaining momentum, driven by the overarching goal of minimizing the number of pricks inflicted upon neonates, thereby rendering screening a swift, efficient, comfortable, and dependable process. This comprehensive review article delves extensively into the array of non-invasive approaches and digital solutions that have been proposed, implemented, and utilized for neonatal bilirubin screening, with a particular emphasis on their application in low-resource settings. Within this context, the review sheds light on the existing methodologies and their practical applications, with a specific focus on transcutaneous bilirubin meters. Moreover, it underscores the prevailing open challenges in this domain and outlines potential directions for future research endeavors. Notably, the review underscores the imperative need for robust educational programs targeted at both families and healthcare personnel to expedite the process of seeking timely care for neonatal jaundice. Additionally, it underscores the necessity for the development of enhanced screening and diagnostic tools that can offer greater accuracy in clinical practice.

How accurate is transcutaneous bilirubin testing in newborns with darker skin tones?

Fairly accurate. Photometric transcutaneous bilirubin (TcB) testing may overestimate total serum bilirubin (TSB) in neonates with darker skin tones by a mean of 0.68 to > 2 mg/dL (strength of recommendation [SOR]: C, diagnostic cohort studies with differing reference standards).Overall, TcB meters retain accept able accuracy in infants of all skin tones across a range of bilirubin levels, despite being more likely to underestimate lighter skin tones and overestimate darker ones (SOR: C, diagnostic cohort studies with differing reference standards). It is unclear if the higher readings prompt an increase in blood draws or otherwise alter care.

Refining interpretation of transcutaneous bilirubin measurement in newborns born late preterm.

Transcutaneous bilirubin (TCB) monitoring is widely used for jaundice screening in the newborn period. Limited data exists on adjusting TCB for bias in late preterm infants. The objective of this study was to determine the median bias between transcutaneous bilirubin and total serum bilirubin levels in newborns born at 35-36 weeks' gestation. This was a retrospective cohort study of late preterm infants born at 35-0/7 to 36-6/7 weeks' gestation who were admitted to a level III neonatal intensive care unit from May 2018 to February 2020. Transcutaneous and total serum bilirubin levels were assessed within 2h of each other during the first 60h of life. Bland-Altman plots were used to evaluate transcutaneous bilirubin bias. Bilirubin risk stratification based on age (in hours) was done using an adaptation of the Bhutani nomogram for transcutaneous, adjusted transcutaneous, and total serum bilirubin measurements. The median bias between transcutaneous and total serum bilirubin bias was 2.4mg/dL (IQR 1.7-3.4, 95% CI 2.2-2.7). The kappa statistic demonstrated slight agreement between the unadjusted transcutaneous bilirubin and total serum bilirubin (k=0.033, p=0.194. The kappa statistic demonstrated fair agreement between an adjusted transcutaneous bilirubin (subtract 1mg/dL) and total serum bilirubin (k=0.298, p<0.0001) and moderate agreement between another adjusted transcutaneous bilirubin (subtract 2mg/dL) and total serum bilirubin (k=0.430, p<0.0001). In a single center study of late preterm infants, transcutaneous bilirubin systematically overestimated the total serum bilirubin level. Subtracting 1mg/dL from the transcutaneous bilirubin identified infants with total serum bilirubin levels in the high or high intermediate risk range. Adjusting the transcutaneous bilirubin prior to risk stratification may reduce unnecessary blood draws for total serum bilirubin. Studies of racially and ethnically diverse newborns using various transcutaneous bilirubin meters are needed prior to broad application of the adjusted transcutaneous bilirubin approach.

Self-Powered Wearable Biosensor in a Baby Diaper for Monitoring Neonatal Jaundice through a Hydrovoltaic-Biosensing Coupling Effect of ZnO Nanoarray.

Neonatal jaundice refers to the abnormality of bilirubin metabolism for newborns, and wearable transcutaneous bilirubin meters for real-time measuring the bilirubin concentration is an insistent demand for the babies’ parents and doctors. In this paper, a self-powered wearable biosensor in a baby diaper for real-time monitoring neonatal jaundice has been realized by the hydrovoltaic-biosensing coupling effect of ZnO nanoarray. Without external power supply, the system can work independently, and the hydrovoltaic output can be treated as both the power source and biosensing signal. The working mechanism is that the hydrovoltaic output arises from the urine flowing on ZnO nanoarray and the enzymatic reaction on the surface can influence the output. The sensing information can be transmitted through a wireless transmitter, and thus the parents and doctors can treat the neonatal jaundice of babies in time. This work can potentially promote the development of next generation of biosensors and physiological monitoring system, and expand the scope of self-powered technique and smart healthcare area.

Implementation of a Neonatal Hyperbilirubinemia Clinical Pathway in a Pediatric Emergency Department

<h3>Category/Date</h3> Practice Innovation Poster presented at NAPNAP's 42nd National Conference on Pediatric Health Care, March 24th, 2021. https://napnap21.org/community/#/home <h3>Problem Statement</h3> Within the Pediatric Emergency Department, no protocol exists for the management of neonatal hyperbilirubinemia. Currently the management of infants with hyperbilirubinemia varies widely between providers. This practice gap leads to inconsistent delivery of care in the ED and variations in treatment timing with phototherapy. Within the department the median time from arrival to initiation of phototherapy is 103 minutes and the goal is to start phototherapy within 60 minutes of arrival. <h3>Purpose of Project & Goals</h3> The purpose of this QI project is to implement an evidenced based neonatal hyperbilirubinemia clinical pathway in pediatric ED. The goal is to decrease the time from arrival to initiation of phototherapy and thus decrease length of stay in the emergency department. <h3>Methods</h3> Development of a nurse-initiated Hyperbilirubinemia Clinical Pathway and associated nursing order set allows nursing staff to obtain a neonatal bilirubin blood panel and initiate phototherapy. This allows for the evaluation and treatment of infants with known or suspected hyperbilirubinemia to begin prior to provider assessment. The Clinical Pathway was approved by the hospital's medical executive committee and department of nursing. <h3>Results</h3> After pathway implementation time to phototherapy decreased from an average of 103 minutes to 27 minutes. There was also an associated decrease in the number of patients who received an intravenous catheter in the ED. <h3>Discussion</h3> After implementation of a nurse-initiated hyperbilirubinemia clinical pathway, the time from arrival to phototherapy was reduced by 74%, ED length of stay decreased from 240 minutes to 179 minutes and IV catheter placement was reduced by 27%. Based upon the literature these results were expected because early initiation of phototherapy and standardization of hyperbilirubinemia management is associated with improved outcomes. <h3>Conclusions</h3> The pathway can be modified and implemented in community EDs in order to improve care of neonates with hyperbilirubinemia. Further research is needed regarding the use of transcutaneous bilirubin meter in the ED setting and the utility of its addition to the clinical pathway <h3>IRB Approval</h3> The project was reviewed by the hospitals and the university IRB committee and demeaned non research, quality improvement <h3>Funding</h3> No funding was obtained for this project

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

The study aimed to evaluate the validity of transcutaneous bilirubin (TcB) measurements at three sites in premature infants born at 230/7 to 346/7 weeks' gestational age (GA) compared with total serum bilirubin (TSB) measurements. 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 230/7 to 286/7 weeks' GA and Cohort B contained subjects 290/7 to 346/7 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. 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. 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. · 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..

Covered Skin Bilirubin Measurement during Phototherapy, in Comparison with Total Serum Bilirubin in Full Term Neonates

Background Jaundice is a prevalent problem among neonates. Patients undergoing phototherapy need a close follow-up of their serum bilirubin levels to determine the treatment response. To make a comparison between transcutaneous bilirubin measurements (TcB) from covered skin areas during phototherapy and total serum bilirubin (TSB) levels.Methods This prospective observational study was conducted on 30 full-term neonates with indirect hyperbilirubinemia requiring phototherapy. Some parts of the skin (forehead and sternum) were covered in each neonate using the BiliEclipsephoto opaque patch and this covered site was used to measure TcB during phototherapy and compare it with TSB. Both TSB and TcB estimation were performed on icteric newborns before, as well as 24 and 48 h of exposure to phototherapy.Results As demonstrated by the obtained results, TSB was not significantly different from TcB measured at forehead and sternum before phototherapy. Moreover, no significant difference was detected between TSB and TcB from the covered forehead and sternum in 24 and 48 h of phototherapy initiation. There was a highly significant positive correlation between TSB and covered forehead/sternum TcB during phototherapy. There was no significant difference in both covered forehead and sternum TcB according to different used TcB devices.Conclusion Measurement of TcB from the covered area of the skin during phototherapy using transcutaneous bilirubin meters is a reliable method to assess TSB in full-term neonates and could lead to a reduction in blood sampling and its complications.

Improving quality of transcutaneous bilirubin measurements: Value of in-house developed quality control

ObjectivesQuality assurance (QA) plays an integral role in Point of Care Testing (POCT) programs. Quality control (QC) is an important QA program component to ensure high quality results and enhanced patient care. The measurement of transcutaneous bilirubin (TcB) in the POCT setting is an essential part of newborn care in Alberta, Canada. However, there is currently no available commercial QC material for TcB meters. An in-house developed QC material has been in use within a single TcB POCT program within Alberta. The objective of this study was to determine the performance of this QC material by other POCT staff and clinical end-users to assess whether its use could be expanded. Design and methodsTwo levels of QC material were measured by POCT staff and clinical end-users across 12 different sites using the Dräger Jaundice Meter JM-103® and JM-105® meters. ResultsThe performance of the QC material was acceptable when tested by POCT staff, was stable and reliable over time, and had an acceptable CV (≤8%). However, the data does not support use of the QC material by clinical end-users. ConclusionsThe use of the QC material could be expanded into other TcB settings for use by POCT staff. Additional training and experience with the QC material by end-users is needed to facilitate QC use in the clinical setting.

Inter-device reproducibility of transcutaneous bilirubin meters

BackgroundTranscutaneous bilirubinometry is a widely used screening method for neonatal hyperbilirubinemia. Deviation of the transcutaneous bilirubin concentration (TcB) from the total serum bilirubin concentration (TSB) is often ascribed to biological variation between patients, but variations between TcB meters may also have a role. This study aims to provide a systematic evaluation of the inter-device reproducibility of TcB meters.Materials and MethodsThirteen commercially available TcB meters (JM-105 and JM-103) were evaluated in vitro on phantoms that optically mimic neonatal skin. The mimicked TcB was varied within the clinical range (0.5–181.3 μmol/L).ResultsAbsolute differences between TcB meter outcomes increased with the measured TcB, from a difference of 5.0 μmol/L (TcB = 0.5 μmol/L phantom) up to 65.0 μmol/L (TcB = 181.3 μmol/L phantom).ConclusionThe inter-device reproducibility of the examined TcB meters is substantial and exceeds the specified accuracy of the device (±25.5 μmol/L), as well as the clinically used TcB safety margins (>50 µmol/L below phototherapy threshold). Healthcare providers should be well aware of this additional uncertainty in the TcB determination, especially when multiple TcB meters are employed in the same clinic. We strongly advise using a single TcB meter per patient to evaluate the TcB over time.ImpactKey message: The inter-device reproducibility of TcB meters is substantial and exceeds the clinically used TcB safety margins.What this study adds to existing literature: The inter-device reproducibility of transcutaneous bilirubin (TcB) meters has not been reported in the existing literature. This in vitro study systematically evaluates this inter-device reproducibility.Impact: This study aids in a better interpretation of the measured TcB value from a patient and is of particular importance during patient monitoring when using multiple TcB meters within the same clinical department. We strongly advise using a single TcB meter per patient to evaluate the TcB over time.

How skin anatomy influences transcutaneous bilirubin determinations: an in vitro evaluation

BackgroundTranscutaneous bilirubinometry is an effective screening method for neonatal hyperbilirubinemia. Current transcutaneous bilirubin (TcB) meters are designed for the “standard” situation of TcB determinations on the forehead or sternum of term newborns. We hypothesize that skin anatomy can considerably influence TcB determinations in non-standard situations—e.g., on preterm newborns or alternative body locations.MethodsA commercially available TcB meter (JM-105) was evaluated in vitro on phantoms that accurately mimic neonatal skin. We varied the mimicked cutaneous hemoglobin content (0–2.5 g/L), bone depth (0.26–5.26 mm), and skin maturity-related light scattering (1.36–2.27 mm−1) within the clinical range and investigated their influence on the TcB determination. To obtain a reference frame for bone depth at the forehead, magnetic resonance head scans of 46 newborns were evaluated.ResultsThe TcB meter adequately corrected for mimicked hemoglobin content. However, TcB determinations were influenced considerably by clinically realistic variations in mimicked bone depth and light scattering (deviations up to 72 µmol/L). This greatly exceeds the specified accuracy of the device (±25.5 µmol/L).ConclusionAs bone depth and light scattering vary with gestational maturity and body location, caretakers should be cautious when interpreting TcB measurements on premature newborns and non-standard body locations.

A pilot study demonstrating the efficacy of transcutaneous bilirubin meters to quantitatively differentiate contusions from Congenital Dermal Melanocytosis

ObjectiveCongenital Dermal Melanocytosis (CDM) can be difficult to differentiate from contusions. The need for a prompt and accurate diagnosis is best illustrated in cases where child abuse and maltreatment is of concern. Transcutaneous bilirubin (TCB) spectrophotometry has been well established to measure bilirubin under the skin for jaundice in infants. The use of TCB spectrometry has not been used to identify or differentiate contusions from CDM. We hypothesized that bilirubin, a degradation product of hemoglobin, would be elevated in contusions but not in CDM thus demonstrating the efficacy of a novel diagnostic technique to compliment or improve on physical assessment alone. MethodsPilot study with thirty-seven infants and children noted to have CDM and fifty-six infants, children and adults with contusions underwent measurement of their lesion with TCB spectrometry. In each patient, the affected skin was scanned along with the adjacent unaffected native skin allowing an internal control for individual pigment variation. ResultsTCB measurements of CDM resulted in lower transcutaneous bilirubin values that were not significantly different from adjacent native skin pigmentation. This was in contrast to cutaneous contusions, which resulted in a higher measured value (mean 5.01 mg/dL) compared to adjacent native tissue (1.24 mg/dL) demonstrating a four-fold increase in measurement at the lesion site (P < 0.001). Direct comparison of a ΔTCB value (lesion measurement minus the adjacent tissue) demonstrated a significantly higher value in contusions compared to CDM with a mean value of 3.77 and 0.12 mg/dL, respectively (P < 0.001). ConclusionsTCB Spectrometry as a novel diagnostic technique has the potential to discern contusions from CDM and may therefore have the ability to compliment the use of physical assessment alone.

Transcutaneous Bilirubin Assessment for Screening of Hyperbilirubinemia in Term and Near-Term Neonates with Jaundice, a Comparative Study

Introduction: Hyperbilirubinemia is a common condition in neonates. In this study, we aimed to investigate the association of total serum bilirubin (TSB) with sternum transcutaneous bilirubin (TcB) level obtained by KJ-8000 Transcutaneous bilirubin meter (KEJIAN medical apparatus). Methods: Eighty newborns were enrolled in the present prospective cross-sectional study. At first, blood sampling was performed for determination of TSB, and immediately after that, TcB levels were recorded at the sternum skin by KJ-8000 device. Data was analyzed by statistical software SPSS version 21.0. Results: The mean gestational age of the infants was 38.2±1.5 weeks. The mean level of TSB was 13.52±4 mg/dL, while the mean value of TcB was 13.71±3.53 mg/dL. Pearson correlation analysis showed a correlation coefficient of r=0.770 between sternum TcB recorded by KJ-8000 device and TSB. Conclusion: Given a strong correlation between TcB and TSB levels, it is advised the transcutaneous bilirubinometery be considered as the screening method in infant jaundice.

Accuracy of transcutaneous bilirubinometer in assessing jaundice in newborns in Indian context

Background: Jaundice is a very common problem in newborns. Though measuring serum bilirubin is considered the gold standard method for estimating jaundice, Transcutaneous Bilirubin (TCB) measurement by TCB meter is now used in various centers. The accuracy of TCB meter is affected by many factors, skin colour being one of them. Aim: To analyze the accuracy of TCB meter in comparison to serum bilirubin for assessing jaundice in babies with different skin colours, in a tertiary care centre in South India. Methods: The study was performed in 200 babies in a medical college, in South India over a period of five months from august 2016 to December 2016. Term babies upto 7th post natal day without any complications were analyzed. Babies were categorized based on their skin colour into 6 groups using the Fitz Patrick’s colour scale. Jaundice was quantified in these babies by TCB meter and by measuring serum bilirubin at the same time and the values were compared. Results: Out of 200 babies, 6 babies were in group 2, 100 in group 3, 83 in group 4 and 11 in group 5. Though the Pearson correlation was linear in all the groups, it was lesser in the dark skinned babies. So we concluded that assessment of jaundice by TCB meter is not accurate in dark skinned babies. Hence serum bilirubin must be done in these babies before intervention. Conclusion: TCB is not accurate in assessing jaundice in dark skinned babies. Still it can be used as a valid screening tool.

Effect of phototherapy on the diagnostic accuracy of transcutaneous bilirubin in preterm infants

Objectives: The objective of this study was to evaluate the diagnostic accuracy of JM-103 transcutaneous bilirubinmeter (TcB) in preterm infants during phototherapy (PT) and in post-PT phase. Methods: This was a prospective cohort study. Infants born between 28 and 35 weeks of gestation and at <28 days of postnatal age were eligible if they required bilirubin estimation during the NICU stay. TcB was measured within 30 minutes of the blood sampling for serum bilirubin, at forehead and sternum. Mean difference (±standard deviation [SD]) and 95% limits of agreement between TcB and total serum bilirubin (TSB) were calculated by analyzing Bland–Altman difference plots. We also calculated correlation coefficients. Results: Ninety infants were enrolled. During PT, the difference plots revealed a wide TcB-TSB disagreement; 95% agreement limits of data indicated that TcB could underestimate bilirubin levels by up to 132 μmol/L at forehead and 157 μmol/L at sternum (Mean difference ± SD of −52.4 mmol/L ± 40.7 at forehead and −69.2 mmol/L ± 42.5 at sternum) and a poor TcB-TSB correlation (r = 0.72 at forehead and 0.51 at sternum). In post-PT phase, correlation coefficients improved significantly and were equivalent to the estimates before the onset of PT (r = 0.88 at forehead and 0.87 at sternum). The analyses of difference plots revealed that TcB could underestimate bilirubin levels up to 88 μmol/L in this phase (Mean difference ± SD of −28.8 mmol/L ± 30.5 at forehead and −19.6 mmol/L ± 34.7 at sternum). Conclusions: JM-103 device is unreliable for estimating bilirubin during PT. However, TcB-TSB agreement improved substantially in the post-PT phase such that use of the TcB device could lead to a reduction in blood sampling during this phase.

Validation of a transcutaneous bilirubin meter in Mongolian neonates: comparison with total serum bilirubin

BackgroundNeonatal hyperbilirubinemia, especially kernicterus, can be prevented by screening for neonatal jaundice. The transcutaneous bilirubin (TcB) meter is a non-invasive medical device for screening neonates. The study aimed to investigate the validity of a TcB meter in a resource-limited setting such as Mongolia.MethodsTerm and late preterm neonates from the National Center for Maternal and Child Health of Ulaanbaatar in Mongolia who met the inclusion criteria (gestational age ≥35 weeks, birth weight ≥2000 g, postnatal age ≤ 1 month) were enrolled in the study. We used a TcB meter, JM-103 to screen for neonatal jaundice. TcB measurements at the infant’s forehead and midsternum were performed within 3 h of obtaining samples for total serum bilirubin (TSB) measurement. We analyzed the correlation between TcB measurements and TSB measurements to validate the meter.ResultsA total of 47 term and six late preterm neonates were included in the study. TcB measured by the meter at both the forehead and the midsternum showed a strong correlation with TSB measured in the laboratory. The correlation equations were TSB = 1.409+0.8655 × TcB (R2=0.78871) at the forehead, and TSB = 0.7555+0.8974 × TcB (R2=0.78488) at the midsternum. Bland-Altman plots and the Bradley-Blackwood test showed no significant differences between the two methods at all measured ranges of bilirubin. The mean areas under the curves of TcB at the forehead and midsternum at three TSB levels (>10 mg/dL, >13 mg/dL, >15 mg/dL) of TcB were greater than 0.9, and all had high sensitivity and specificity.ConclusionsThis study established the validity of the JM-103 meter as a screening tool for neonatal jaundice in term and late preterm infants in Mongolia. Future studies are needed, including the establishment of a TcB hour-specific nomogram, for more effective clinical practice to prevent severe hyperbilirubinemia.

Is measuring the wavelengths for transcutaneous bilirubin meter sufficient to detect instrument malfunction?

Is measuring the wavelengths for transcutaneous bilirubin meter sufficient to detect instrument malfunction?

BiliChek transcutaneous bilirubin meter overestimates serum bilirubin as measured by the Doumas reference method

Objectives To determine the relationship between BiliChek TcB (Respironics, Marietta GA) and Doumas reference serum or plasma total bilirubin (TSB). Design and methods Pooled samples with values assigned by the Doumas reference method were used to establish the relationship between a local laboratory and reference Doumas TSB. We then established the relationship between TcB and TSB in the 3 months before and after reassignment of calibrator setpoints undertaken to match the local laboratory to Doumas reference bilirubin values. Results Before calibrator setpoint reassignment TSB as measured in our laboratory overestimated Doumas reference bilirubin. After calibrator adjustment laboratory TSB was within 1.7–6.8 µmol/L (0.1–0.4 mg/dL) of Doumas reference values. Mean bias between BiliChek TcB and TSB was 42.8 ± 22.2 µmol/L (2.5 ± 1.3 mg/dL) ( n = 94) before and 49.6 ± 22.2 µmol/L (2.9 ± 1.3 mg/dL) ( n = 115) after calibration adjustment. Conclusions BiliChek TcB significantly overestimates TSB as measured by the Doumas reference method.

Transcutaneous Bilirubinometry Interinstrumental Variability of TcB Instruments

We studied the interinstrumental variability of the transcutaneous bilirubin meter (TcB) in 35 high risk neonates, using eight commercially available TcB instruments. Our study showed that commercially available TcB instruments were stable and had little interinstrumental variability for repeated TcB measurements at the forehead, chest, and sternum.

Transcutaneous Bilirubin Measurements: Variation in Meter Response

The transcutaneous bilirubin meter has been shown to be a useful screening device for the identification of significant neonatal jaundice in full-term infants.1-3 Investigators have, nevertheless, emphasized the necessity for each institution to establish the relationship between the transcutaneous bilirubin index, as measured with a particular instrument, and the serum bilirubin determination obtained from the institution's laboratory. 3 This is important, because of the known variation between laboratories in the measurement of serum bilirubin concentration4 and because no information has been published regarding the potential variation in the response of different transcutaneous bilirubin meters.