Physiological-based cord clamping in very preterm infants: the Aeration, Breathing, Clamping 3 (ABC3) trial-statistical analysis plan for a multicenter randomized controlled trial

BACKGROUND

Mortality, cerebral injury, and necrotizing enterocolitis (NEC) are common complications of very preterm birth. An important risk factor for these complications is hemodynamic instability. Pre-clinical studies suggest that the timing of umbilical cord clamping affects hemodynamic stability during transition. Standard care is time-based cord clamping (TBCC), with clamping irrespective of lung aeration. It is unknown whether delaying cord clamping until lung aeration and ventilation have been established (physiological-based cord clamping, PBCC) is more beneficial. This document describes the statistical analyses for the ABC3 trial, which aims to assess the efficacy and safety of PBCC, compared to TBCC.

METHODS

The ABC3 trial is a multicenter, randomized trial investigating PBCC (intervention) versus TBCC (control) in very preterm infants. The trial is ethically approved. Preterm infants born before 30 weeks of gestation are randomized after parental informed consent. The primary outcome is intact survival, defined as the composite of survival without major cerebral injury and/or NEC. Secondary short-term outcomes are co-morbidities and adverse events assessed during NICU admission, parental reported outcomes, and long-term neurodevelopmental outcomes assessed at a corrected age of 2 years. To test the hypothesis that PBCC increases intact survival, a logistic regression model will be estimated using generalized estimating equations (accounting for correlation between siblings and observations in the same center) with treatment and gestational age as predictors. This plan is written and submitted without knowledge of the data.

DISCUSSION

The findings of this trial will provide evidence for future clinical guidelines on optimal cord clamping management at birth.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03808051. Registered on 17 January 2019.

Ischemia modified albumin as a marker of hypoxia in preterm infants in the first week after birth

BACKGROUND

Tissue hypoxia remains a leading cause of morbidity and mortality in preterm infants. Current biomarkers often detect irreversible hypoxic cellular injury (i.e. lactate) and are non-specific. A new biomarker is needed which detects tissue hypoxia before irreversible damage occurs.

AIMS

To investigate the relation between serum ischemia modified albumin (IMA), a marker of hypoxia; and analytic variables, patient related variables and conditions associated with hypoxia, in preterm infants.

STUDY DESIGN

Retrospective cohort study.

SUBJECTS

Infants with a gestational age < 30 weeks and/or birth weight < 1000 g.

OUTCOME MEASURES

We collected two remnant blood samples in the first week after birth and measured IMA. IMA/albumin ratio (IMAR) was used to adjust for albumin. We assessed correlations between IMA(R) and analytic variables (albumin, lipemia- and haemolysis index); mean-2 h SpO2; mean-2 h variability of regional splanchnic oxygen saturation (rsSO2), measured using near-infrared spectroscopy; and patent ductus arteriosus (PDA).

RESULTS

Sixty-five infants were included. Albumin, the lipemia- and haemolysis index correlated negatively with IMA (r:-0.620, P<0.001; r:-0.458, P<0.001; and r:-0.337, P=0.002). IMAR correlated negatively with SpO2 (rho:-0.614, P<0.001). Lower rsSO2 variability correlated with higher IMAR values (rho:-0.785, n=14, P=0.001 and rho:-0.773, n=11, P=0.005). Infants with a hemodynamic significant PDA (hsPDA) had higher IMAR values than infants without PDA (0.13 [0.11-0.28], n=16 vs. 0.11 [0.08-0.20], n=29, P=0.005 and 0.11 [0.09-0.18], n=13 vs. 0.09 [0.06-0.17], n=37, P=0.026).

CONCLUSIONS

When adjusted for albumin, the lipemia- and haemolysis index, IMAR has potential value as a marker for systemic hypoxia in preterm infants, considering the associations with SpO2, variability of rsSO2, and hsPDA.

Two-Year Outcomes After Minimally Invasive Surfactant Therapy in Preterm Infants: Follow-Up of the OPTIMIST-A Randomized Clinical Trial

Importance

The long-term effects of surfactant administration via a thin catheter (minimally invasive surfactant therapy [MIST]) in preterm infants with respiratory distress syndrome remain to be definitively clarified.

Objective

To examine the effect of MIST on death or neurodevelopmental disability (NDD) at 2 years' corrected age.

Design, Setting, and Participants

Follow-up study of a randomized clinical trial with blinding of clinicians and outcome assessors conducted in 33 tertiary-level neonatal intensive care units in 11 countries. The trial included 486 infants with a gestational age of 25 to 28 weeks supported with continuous positive airway pressure (CPAP). Collection of follow-up data at 2 years' corrected age was completed on December 9, 2022.

Interventions

Infants assigned to MIST (n = 242) received exogenous surfactant (200 mg/kg poractant alfa) via a thin catheter; those assigned to the control group (n = 244) received sham treatment.

Main Outcomes and Measures

The key secondary outcome of death or moderate to severe NDD was assessed at 2 years' corrected age. Other secondary outcomes included components of this composite outcome, as well as hospitalizations for respiratory illness and parent-reported wheezing or breathing difficulty in the first 2 years.

Results

Among the 486 infants randomized, 453 had follow-up data available (median gestation, 27.3 weeks; 228 females [50.3%]); data on the key secondary outcome were available in 434 infants. Death or NDD occurred in 78 infants (36.3%) in the MIST group and 79 (36.1%) in the control group (risk difference, 0% [95% CI, -7.6% to 7.7%]; relative risk [RR], 1.0 [95% CI, 0.81-1.24]); components of this outcome did not differ significantly between groups. Secondary respiratory outcomes favored the MIST group. Hospitalization with respiratory illness occurred in 49 infants (25.1%) in the MIST group vs 78 (38.2%) in the control group (RR, 0.66 [95% CI, 0.54-0.81]) and parent-reported wheezing or breathing difficulty in 73 (40.6%) vs 104 (53.6%), respectively (RR, 0.76 [95% CI, 0.63-0.90]).

Conclusions and Relevance

In this follow-up study of a randomized clinical trial of preterm infants with respiratory distress syndrome supported with CPAP, MIST compared with sham treatment did not reduce the incidence of death or NDD by 2 years of age. However, infants who received MIST had lower rates of adverse respiratory outcomes during their first 2 years of life.

Trial Registration

anzctr.org.au Identifier: ACTRN12611000916943.

Diagnostic Accuracy of Portable, Handheld Point-of-Care Tests vs Laboratory-Based Bilirubin Quantification in Neonates: A Systematic Review and Meta-analysis

Importance

Quantification of bilirubin in blood is essential for early diagnosis and timely treatment of neonatal hyperbilirubinemia. Handheld point-of-care (POC) devices may overcome the current issues with conventional laboratory-based bilirubin (LBB) quantification.

Objective

To systematically evaluate the reported diagnostic accuracy of POC devices compared with LBB quantification.

Data Sources

A systematic literature search was conducted in 6 electronic databases (Ovid MEDLINE, Embase, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, CINAHL, and Google Scholar) up to December 5, 2022.

Study Selection

Studies were included in this systematic review and meta-analysis if they had a prospective cohort, retrospective cohort, or cross-sectional design and reported on the comparison between POC device(s) and LBB quantification in neonates aged 0 to 28 days. Point-of-care devices needed the following characteristics: portable, handheld, and able to provide a result within 30 minutes. This study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline.

Data Extraction and Synthesis

Data extraction was performed by 2 independent reviewers into a prespecified, customized form. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Meta-analysis was performed of multiple Bland-Altman studies using the Tipton and Shuster method for the main outcome.

Main Outcomes and Measures

The main outcome was mean difference and limits of agreement in bilirubin levels between POC device and LBB quantification. Secondary outcomes were (1) turnaround time (TAT), (2) blood volumes, and (3) percentage of failed quantifications.

Results

Ten studies met the inclusion criteria (9 cross-sectional studies and 1 prospective cohort study), representing 3122 neonates. Three studies were considered to have a high risk of bias. The Bilistick was evaluated as the index test in 8 studies and the BiliSpec in 2. A total of 3122 paired measurements showed a pooled mean difference in total bilirubin levels of -14 μmol/L, with pooled 95% CBs of -106 to 78 μmol/L. For the Bilistick, the pooled mean difference was -17 μmol/L (95% CBs, -114 to 80 μmol/L). Point-of-care devices were faster in returning results compared with LBB quantification, whereas blood volume needed was less. The Bilistick was more likely to have a failed quantification compared with LBB.

Conclusions and Relevance

Despite the advantages that handheld POC devices offer, these findings suggest that the imprecision for measurement of neonatal bilirubin needs improvement to tailor neonatal jaundice management.

Fecal Volatile Metabolomics Predict Gram-Negative Late-Onset Sepsis in Preterm Infants: A Nationwide Case-Control Study

Early detection of late-onset sepsis (LOS) in preterm infants is crucial since timely treatment initiation is a key prognostic factor. We hypothesized that fecal volatile organic compounds (VOCs), reflecting microbiota composition and function, could serve as a non-invasive biomarker for preclinical pathogen-specific LOS detection. Fecal samples and clinical data of all preterm infants (≤30 weeks’ gestation) admitted at nine neonatal intensive care units in the Netherlands and Belgium were collected daily. Samples from one to three days before LOS onset were analyzed by gas chromatography—ion mobility spectrometry (GC-IMS), a technique based on pattern recognition, and gas chromatography—time of flight—mass spectrometry (GC-TOF-MS), to identify unique metabolites. Fecal VOC profiles and metabolites from infants with LOS were compared with matched controls. Samples from 121 LOS infants and 121 matched controls were analyzed using GC-IMS, and from 34 LOS infants and 34 matched controls using GC-TOF-MS. Differences in fecal VOCs were most profound one and two days preceding Escherichia coli LOS (Area Under Curve; p-value: 0.73; p = 0.02, 0.83; p < 0.002, respectively) and two and three days before gram-negative LOS (0.81; p < 0.001, 0.85; p < 0.001, respectively). GC-TOF-MS identified pathogen-specific discriminative metabolites for LOS. This study underlines the potential for VOCs as a non-invasive preclinical diagnostic LOS biomarker.

Better assessment of neonatal jaundice at home (BEAT Jaundice @home): protocol for a prospective, multicentre diagnostic study

INTRODUCTION

Severe neonatal hyperbilirubinaemia can place a neonate at risk for acute bilirubin encephalopathy and kernicterus spectrum disorder. Early diagnosis is essential to prevent these deleterious sequelae. Currently, screening by visual inspection followed by laboratory-based bilirubin (LBB) quantification is used to identify hyperbilirubinaemia in neonates cared for at home in the Netherlands. However, the reliability of visual inspection is limited. We aim to evaluate the effectiveness of universal transcutaneous bilirubin (TcB) screening as compared with visual inspection to: (1) increase the detection of hyperbilirubinaemia necessitating treatment, and (2) reduce the need for heel pricks to quantify bilirubin levels. In parallel, we will evaluate a smartphone app (Picterus), and a point-of-care device for quantifying total bilirubin (Bilistick) as compared with LBB.

METHODS AND ANALYSIS

We will undertake a multicentre prospective cohort study in nine midwifery practices across the Netherlands. Neonates born at a gestational age of 35 weeks or more are eligible if they: (1) are at home at any time between days 2 and 8 of life; (2) have their first midwife visit prior to postnatal day 6 and (3) did not previously receive phototherapy. TcB and the Picterus app will be used after visual inspection. When LBB is deemed necessary based on visual inspection and/or TcB reading, Bilistick will be used in parallel. The coprimary endpoints of the study are: (1) hyperbilirubinaemia necessitating treatment; (2) the number of heel pricks performed to quantify LBB. We aim to include 2310 neonates in a 2-year period. Using a decision tree model, a cost-effectiveness analysis will be performed.

ETHICS AND DISSEMINATION

This study has been approved by the Medical Research Ethical Committee of the Erasmus MC Rotterdam, Netherlands (MEC-2020-0618). Parents will provide written informed consent. The results of this study will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

Dutch Trial Register (NL9545).

Physiological-based cord clamping in very preterm infants: the Aeration, Breathing, Clamping 3 (ABC3) trial-study protocol for a multicentre randomised controlled trial

BACKGROUND

International guidelines recommend delayed umbilical cord clamping (DCC) up to 1 min in preterm infants, unless the condition of the infant requires immediate resuscitation. However, clamping the cord prior to lung aeration may severely limit circulatory adaptation resulting in a reduction in cardiac output and hypoxia. Delaying cord clamping until lung aeration and ventilation have been established (physiological-based cord clamping, PBCC) allows for an adequately established pulmonary circulation and results in a more stable circulatory transition. The decline in cardiac output following time-based delayed cord clamping (TBCC) may thus be avoided. We hypothesise that PBCC, compared to TBCC, results in a more stable transition in very preterm infants, leading to improved clinical outcomes. The primary objective is to compare the effect of PBCC on intact survival with TBCC.

METHODS

The Aeriation, Breathing, Clamping 3 (ABC3) trial is a multicentre randomised controlled clinical trial. In the interventional PBCC group, the umbilical cord is clamped after the infant is stabilised, defined as reaching heart rate > 100 bpm and SpO₂ > 85% while using supplemental oxygen < 40%. In the control TBCC group, cord clamping is time based at 30-60 s. The primary outcome is survival without major cerebral and/or intestinal injury. Preterm infants born before 30 weeks of gestation are included after prenatal parental informed consent. The required sample size is 660 infants.

DISCUSSION

The findings of this trial will provide evidence for future clinical guidelines on optimal cord clamping management in very preterm infants at birth.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03808051. First registered on January 17, 2019.

Severe neonatal hyperbilirubinaemia: lessons learnt from a national perinatal audit

OBJECTIVES

To describe characteristics of neonates with severe neonatal hyperbilirubinaemia (SNH) and to gain more insight in improvable factors that may have contributed to the development of SNH.

DESIGN AND SETTING

Descriptive study, based on national Dutch perinatal audit data on SNH from 2017 to 2019.

PATIENTS

Neonates, born ≥35 weeks of gestation and without antenatally known severe blood group incompatibility, who developed hyperbilirubinaemia above the exchange transfusion threshold.

MAIN OUTCOME MEASURES

Characteristics of neonates having SNH and corresponding improvable factors.

RESULTS

During the 3-year period, 109 neonates met the eligibility criteria. ABO antagonism was the most frequent cause (43%). All neonates received intensive phototherapy and 30 neonates (28%) received an exchange transfusion. Improvable factors were mainly related to lack of knowledge, poor adherence to the national hyperbilirubinaemia guideline, and to incomplete documentation and insufficient communication of the a priori hyperbilirubinaemia risk assessment among healthcare providers. A priori risk assessment, a key recommendation in the national hyperbilirubinaemia guideline, was documented in only six neonates (6%).

CONCLUSIONS

SNH remains a serious threat to neonatal health in the Netherlands. ABO antagonism frequently underlies SNH. Lack of compliance to the national guideline including insufficient a priori hyperbilirubinaemia risk assessment, and communication among healthcare providers are important improvable factors. Implementation of universal bilirubin screening and better documentation of the risk of hyperbilirubinaemia may enhance early recognition of potentially dangerous neonatal jaundice.

Irradiance footprint of phototherapy devices: a comparative study

BACKGROUND

Phototherapy (PT) is the standard treatment of neonatal unconjugated hyperbilirubinemia. The irradiance footprint, i.e., the illuminated area by the PT device with sufficient spectral irradiance, is essential for PT to be effective. Irradiance footprint measurements are not performed in current clinical practice. We describe a user-friendly method to systematically evaluate the high spectral irradiance (HSI) footprint (illuminated area with spectral irradiance of ≥30 μW cm^-2 nm^-1) of PT devices in clinical practice.

MATERIALS AND METHODS

Six commercially available LED-based overhead PT devices were evaluated in overhead configuration with an incubator. Spectral irradiance (µW cm^-2 nm^-1) and HSI footprint were measured with a radiospectrometer (BiliBlanket Meter II).

RESULTS

The average measured spectral irradiance ranged between 27 and 52 μW cm^-2 nm^-1 and HSI footprint ranged between 67 and 1465 cm², respectively. Three, two, and one PT devices out of six covered the average BSA of an infant born at 22, 26-32, and 40 weeks of gestation, respectively.

CONCLUSION

Spectral irradiance of LED-based overhead PT devices is often lower than manufacturer's specifications, and HSI footprints not always cover the average BSA of a newborn infant. The proposed measurement method will contribute to awareness of the importance of irradiance level as well as footprint measurements in the management of neonatal jaundice.

IMPACT

While a sufficient spectral irradiance footprint is essential for PT to be effective, some PT devices have spectral irradiance footprints that are too small to cover the entire body surface area (BSA) of a newborn infant. This study introduces a user-friendly, accessible method to systematically evaluate the spectral irradiance level and footprint of PT devices. This study supports awareness on the role of the spectral irradiance footprint in the efficacy of PT devices. Irradiance footprint can be easily measured during phototherapy with the proposed method.

Effect of Minimally Invasive Surfactant Therapy vs Sham Treatment on Death or Bronchopulmonary Dysplasia in Preterm Infants With Respiratory Distress Syndrome: The OPTIMIST-A Randomized Clinical Trial

IMPORTANCE

The benefits of surfactant administration via a thin catheter (minimally invasive surfactant therapy [MIST]) in preterm infants with respiratory distress syndrome are uncertain.

OBJECTIVE

To examine the effect of selective application of MIST at a low fraction of inspired oxygen threshold on survival without bronchopulmonary dysplasia (BPD).

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial including 485 preterm infants with a gestational age of 25 to 28 weeks who were supported with continuous positive airway pressure (CPAP) and required a fraction of inspired oxygen of 0.30 or greater within 6 hours of birth. The trial was conducted at 33 tertiary-level neonatal intensive care units around the world, with blinding of the clinicians and outcome assessors. Enrollment took place between December 16, 2011, and March 26, 2020; follow-up was completed on December 2, 2020.

INTERVENTIONS

Infants were randomized to the MIST group (n = 241) and received exogenous surfactant (200 mg/kg of poractant alfa) via a thin catheter or to the control group (n = 244) and received a sham (control) treatment; CPAP was continued thereafter in both groups unless specified intubation criteria were met.

MAIN OUTCOMES AND MEASURES

The primary outcome was the composite of death or physiological BPD assessed at 36 weeks' postmenstrual age. The components of the primary outcome (death prior to 36 weeks' postmenstrual age and BPD at 36 weeks' postmenstrual age) also were considered separately.

RESULTS

Among the 485 infants randomized (median gestational age, 27.3 weeks; 241 [49.7%] female), all completed follow-up. Death or BPD occurred in 105 infants (43.6%) in the MIST group and 121 (49.6%) in the control group (risk difference [RD], -6.3% [95% CI, -14.2% to 1.6%]; relative risk [RR], 0.87 [95% CI, 0.74 to 1.03]; P = .10). Incidence of death before 36 weeks' postmenstrual age did not differ significantly between groups (24 [10.0%] in MIST vs 19 [7.8%] in control; RD, 2.1% [95% CI, -3.6% to 7.8%]; RR, 1.27 [95% CI, 0.63 to 2.57]; P = .51), but incidence of BPD in survivors to 36 weeks' postmenstrual age was lower in the MIST group (81/217 [37.3%] vs 102/225 [45.3%] in the control group; RD, -7.8% [95% CI, -14.9% to -0.7%]; RR, 0.83 [95% CI, 0.70 to 0.98]; P = .03). Serious adverse events occurred in 10.3% of infants in the MIST group and 11.1% in the control group.

CONCLUSIONS AND RELEVANCE

Among preterm infants with respiratory distress syndrome supported with CPAP, minimally invasive surfactant therapy compared with sham (control) treatment did not significantly reduce the incidence of the composite outcome of death or bronchopulmonary dysplasia at 36 weeks' postmenstrual age. However, given the statistical uncertainty reflected in the 95% CI, a clinically important effect cannot be excluded.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12611000916943.

Profound Pathogen-Specific Alterations in Intestinal Microbiota Composition Precede Late-Onset Sepsis in Preterm Infants: A Longitudinal, Multicenter, Case-Control Study

BACKGROUND

The role of intestinal microbiota in the pathogenesis of late-onset sepsis (LOS) in preterm infants is largely unexplored but could provide opportunities for microbiota-targeted preventive and therapeutic strategies. We hypothesized that microbiota composition changes before the onset of sepsis, with causative bacteria that are isolated later in blood culture.

METHODS

This multicenter case-control study included preterm infants born under 30 weeks of gestation. Fecal samples collected from the 5 days preceding LOS diagnosis were analyzed using a molecular microbiota detection technique. LOS cases were subdivided into 3 groups: gram-negative, gram-positive, and coagulase-negative Staphylococci (CoNS).

RESULTS

Forty LOS cases and 40 matched controls were included. In gram-negative LOS, the causative pathogen could be identified in at least 1 of the fecal samples collected 3 days prior to LOS onset in all cases, whereas in all matched controls, this pathogen was absent (P = .015). The abundance of these pathogens increased from 3 days before clinical onset. In gram-negative and gram-positive LOS (except CoNS) combined, the causative pathogen could be identified in at least 1 fecal sample collected 3 days prior to LOS onset in 92% of the fecal samples, whereas these pathogens were present in 33% of the control samples (P = .004). Overall, LOS (expect CoNS) could be predicted 1 day prior to clinical onset with an area under the curve of 0.78.

CONCLUSIONS

Profound preclinical microbial alterations underline that gut microbiota is involved in the pathogenesis of LOS and has the potential as an early noninvasive biomarker.

The knowledge of Indonesian pediatric residents on hyperbilirubinemia management

Hyperbilirubinemia in the newborn occurs more frequently in Indonesia. Therefore, it is important that pediatric residents in Indonesia acquire adequate knowledge of hyperbilirubinemia management. This study aims to determine the pediatric residents' knowledge on hyperbilirubinemia management, whether they follow recommended guidelines, and whether differences exist between five large Indonesian teaching hospitals. We handed out a 25-question questionnaire on hyperbilirubinemia management to pediatric residents at five teaching hospitals. A total of 250 questionnaires were filled in completely, ranging from 14 to 113 respondents per hospital. Approximately 76% of the respondents used the Kramer score to recognize neonatal jaundice. Twenty-four percent correctly plotted the total serum bilirubin levels (TSB) on the phototherapy (PT) nomograms provided by the American Academy of Pediatrics (AAP) and the National Institute for Health and Care Excellence (NICE) for full-term and nearly full-term infants. Regarding preterm infants <35 weeks' gestational age, 66% of the respondents plotted TSB levels on the AAP nomogram, although this nomogram doesn't apply to this category of infants. Seventy percent of residents knew when to perform an exchange transfusion whereas 27% used a fixed bilirubin cut-off value of 20 mg/dL. Besides PT, 25% reported using additional pharmaceutical treatments, included albumin, phenobarbitone, ursodeoxycholic acid and immunoglobulins, while 47% of the respondents used sunlight therapy, as alternative treatment. The limited knowledge of the pediatric residents could be one factor for the higher incidence of severe hyperbilirubinemia and its sequelae. The limited knowledge of the residents raises doubts about the knowledge of the supervisors and the training of the residents since pediatric residents receive training from their supervisors.

Neonatal donation: are newborns too young to be recognized?

Neonatal organ and tissue donation is not common practice in the Netherlands. At the same time, there is a transplant waiting list for small size-matched organs and tissues. Multiple factors may contribute to low neonatal donation rates, including a lack of awareness of this option. This study provides insight into potential neonatal organ and tissue donors and reports on how many donors were actually reported to the procurement organization. We performed a retrospective analysis of the mortality database and medical records of two largest neonatal intensive care units (NICUs) in the Netherlands. This study reviewed records of neonates with a gestational age >37 weeks and weight >3000g who died in the period from January 1, 2005 through December 31, 2016. During the study period, 259 term-born neonates died in the two NICUs. In total, 132 neonates with general contra-indications for donation were excluded. The medical records of 127 neonates were examined for donation suitability. We identified five neonates with documented brain death who were not recognized as potential organ and/or tissue donors. Of the remaining neonates, 27 were found suitable for tissue donation. One potential tissue donor had been reported to the procurement organization. In three cases, the possibility of donation was brought up by parents.Conclusion: A low proportion (2%) of neonates who died in the NICUs were found suitable for organ donation, and a higher proportion (12%) were found suitable for tissue donation. We suggest that increased awareness concerning the possibility of neonatal donation would likely increase the identification of potential neonatal donors. What is Known: • There is an urgent need for very small organs and tissues from neonatal donors What is New: • A number of neonates who died in the NICU were suitable organ or/and tissue donors but were not recognized as donors. • Knowledge on neonatal donation possibilities is also important for proper counseling of parents who sometimes inquire for the possibility of organ and tissue donation.

Predictive factors for surgical treatment in preterm neonates with necrotizing enterocolitis: a multicenter case-control study

Necrotizing enterocolitis (NEC) is one of the most common and lethal gastrointestinal diseases in preterm infants. Early recognition of infants in need for surgical intervention might enable early intervention. In this multicenter case-control study, performed in nine neonatal intensive care units, preterm born infants (< 30 weeks of gestation) diagnosed with NEC (stage ≥ IIA) between October 2014 and August 2017 were divided into two groups: (1) medical (conservative treatment) and (2) surgical NEC (sNEC). Perinatal, clinical, and laboratory parameters were collected daily up to clinical onset of NEC. Univariate and multivariate logistic regression analyses were applied to identify potential predictors for sNEC. In total, 73 preterm infants with NEC (41 surgical and 32 medical NEC) were included. A low gestational age (p value, adjusted odds ratio [95%CI]; 0.001, 0.91 [0.86-0.96]), no maternal corticosteroid administration (0.025, 0.19 [0.04-0.82]), early onset of NEC (0.003, 0.85 [0.77-0.95]), low serum bicarbonate (0.009, 0.85 [0.76-0.96]), and a hemodynamically significant patent ductus arteriosus for which ibuprofen was administered (0.003, 7.60 [2.03-28.47]) were identified as independent risk factors for sNEC.Conclusions: Our findings may support the clinician to identify infants with increased risk for sNEC, which may facilitate early decisive management and consequently could result in improved prognosis. What is Known: • In 27-52% of the infants with NEC, a surgical intervention is indicated during its disease course. • Absolute indication for surgical intervention is bowel perforation, whereas fixed bowel loop or clinical deterioration highly suggestive of bowel perforation or necrosi, is a relative indication. What is New: • Lower gestational age, early clinical onset, and no maternal corticosteroids administration are predictors for surgical NEC. • Low serum bicarbonate in the 3 days prior clinical onset and patent ductus arteriosus for which ibuprofen was administered predict surgical NEC.

Diagnostic Properties of a Portable Point-of-Care Method to Measure Bilirubin and a Transcutaneous Bilirubinometer

BACKGROUND

Recently, the Bilistick®, a point-of-care instrument to measure bilirubin levels, has been developed. It is fast and cheaper than transcutaneous bilirubin (TCB)-measuring devices, but data on diagnostic properties are scarce.

OBJECTIVE

This study aimed to compare the performance of the Bilistick® (BM-BS 1.0 - FW version 2.0.1) and the JM-105 bilirubinometer for measuring bilirubin.

METHOD

This is a prospective study in infants born after ≥32 weeks' gestation, and/or a birth weight of ≥1,500 g, and a postnatal age ≤14 days in Surabaya, Indonesia. Bilirubin was measured with the Bilistick® System (BM-BS 1.0 - FW version 2.0.1), transcutaneously (TCB) with the JM-105 bilirubinometer, and in serum (TSB) with a routine laboratory technique. Mean differences and 95% limits of agreement (LOA) and correlations were calculated.

RESULT

We enrolled 149 neonates and 126 had paired measurements of Bilistick® bilirubin, TCB, and TSB. Bilistick® failed in 16 (10.7%) infants. Mean Bilistick® bilirubin-TSB difference was -11 µmol/L (95% LOA: -101 to 79 µmol/L) and r = 0.738 (p < 0.001). Mean TCB-TSB difference was 26 μmol/L (95% LOA: -33 to 88) and r = 0.785 (p < 0.001). The sensitivity, specificity, PPV, and NPV for Bilistick® bilirubin for a TSB above treatment thresholds were 0.74, 0.84, 0.67, and 0.88, respectively, and for TCB 0.92, 0.64, 0.54, and 0.95, respectively.

CONCLUSION

The Bilistick® System (BM-BS 1.0 - FW version 2.0.1) underestimates TSB, whereas TCB overestimates TSB in jaundiced Indonesian infants. Further improvement of Bilistick®'s diagnostic accuracy with less false-negative readings is essential to increase its use.

Blue LED phototherapy in preterm infants: effects on an oxidative marker of DNA damage

BACKGROUND

Phototherapy is used on the majority of preterm infants with unconjugated hyperbilirubinaemia. The use of fluorescent tube phototherapy is known to induce oxidative DNA damage in infants and has largely been replaced by blue light-emitting diode phototherapy (BLP). To date, it is unknown whether BLP also induces oxidative DNA damage in preterm infants.

OBJECTIVE

To determine whether BLP in preterm infants induces oxidative DNA damage as indicated by 8-hydroxy-2'deoxyguanosine (8-OHdG).

DESIGN

Observational cohort study.

METHODS

Urine samples (n=481) were collected in a cohort of 40 preterm infants (24-32 weeks' gestational age) during the first week after birth. Urine was analysed for the oxidative marker of DNA damage 8-OHdG and for creatinine, and the 8-OHdG/creatinine ratio was calculated. Durations of phototherapy and levels of irradiance were monitored as well as total serum bilirubin concentrations.

RESULTS

BLP did not alter urinary 8-OHdG/creatinine ratios (B=0.2, 95% CI -6.2 to 6.6) at either low (10-30 µW/cm²/nm) or high (>30 µW/cm²/nm) irradiance: (B=2.3, 95% CI -5.7 to 10.2 and B=-3.0, 95% CI -11.7 to 5.6, respectively). Also, the 8-OHdG/creatinine ratios were independent on phototherapy duration (B=-0.1, 95% CI -0.3 to 0.1).

CONCLUSIONS

BLP at irradiances up to 35 µW/cm²/nm given to preterm infants ≤32 weeks' gestation does not affect 8-OHdG, an oxidative marker of DNA damage.

A homozygous variant in growth and differentiation factor 2 (GDF2) may cause lymphatic dysplasia with hydrothorax and nonimmune hydrops fetalis

The etiology of nonimmune hydrops fetalis is extensive and includes genetic disorders. We describe a term-born female neonate with late onset extensive nonimmune hydrops, that is, polyhydramnios, edema, and congenital bilateral chylothorax. This newborn was successfully treated with repetitive thoracocentesis, total parenteral feeding, octreotide intravenously and finally surgical pleurodesis and corticosteroids. A genetic cause seemed plausible as the maternal history revealed a fatal nonimmune hydrops fetalis. A homozygous truncating variant in GDF2 (c.451C>T, p.(Arg151*)) was detected with exome sequencing. Genetic analysis of tissue obtained from the deceased fetal sibling revealed the same homozygous variant. The parents and two healthy siblings were heterozygous for the GDF2 variant. Skin and lung biopsies in the index patient, as well as the revised lung biopsy of the deceased fetal sibling, showed lymphatic dysplasia and lymphangiectasia. To the best of our knowledge, this is the first report of an association between a homozygous variant in GDF2 with lymphatic dysplasia, hydrothorax and nonimmune hydrops fetalis.

Should transcutaneous bilirubin be measured in preterm infants receiving phototherapy? The relationship between transcutaneous and total serum bilirubin in preterm infants with and without phototherapy

Our objective was to analyze the relationship between transcutaneous bilirubin (TcB) measured on an unexposed area of skin and total serum bilirubin (TSB) in preterm infants before, during, and after phototherapy (PT). For this purpose paired TSB and TcB levels were measured daily during the first ten days after birth in preterm infants of less than 32 weeks’ gestation. TcB was measured with a Dräger Jaundice Meter JM-103 on the covered hipbone. Agreement between TSB and TcB levels was assessed before, during, and after PT. True negative and corresponding false negative percentages were calculated using different TcB cut-off levels. Data are presented as mean (±SD). We obtained 856 paired TcB and TSB levels in 109 preterm infants (66 boys, gestational age 29.4 ± 1.6 weeks and birth weight 1282 g ± 316 g). We found that the difference between TSB and TcB before PT was significantly lower, 44 (±36) μmol/L, than the difference during and after PT, 61 (±29) μmol/L and 63 (±25) μmol/L, respectively; P < 0.01. Blood sampling could be reduced by 42%, with 2% false negatives, when 50 μmol/L was added to the TcB level at 70% of the PT threshold. Our conclusion is that phototherapy enhances underestimation of TSB by TcB in preterms, even if measured on unexposed skin. The use of specific TcB cut-off levels substantially reduces the need for TSB measurements.

Current phototherapy practice on Java, Indonesia

Background

In Indonesia, the burden of severe hyperbilirubinemia is higher compared to other countries. Whether this is related to ineffective phototherapy (PT) is unknown. The aim of this study is to investigate the performance of phototherapy devices in hospitals on Java, Indonesia.

Methods

In 17 hospitals we measured 77 combinations of 20 different phototherapy devices, with and without curtains drawn around the incubator/crib. With a model to mimic the silhouette of an infant, we measured the irradiance levels with an Ohmeda BiliBlanket Meter II, recorded the distance between device and model, and compared these to manufacturers’ specifications.

Results

In nine hospitals the irradiance levels were less than required for standard PT: < 10 μW/cm²/nm and in eight hospitals irradiance failed to reach the levels for intensive phototherapy: 30 μW/cm²/nm. Three hospitals provided very high irradiance levels: > 50 μW/cm²/nm. Half of the distances between device and model were greater than recommended. Distance was inversely correlated with irradiance levels (R² = 0.1838; P < 0.05). The effect of curtains on irradiance levels was highly variable, ranging from − 6.15 to + 15.4 μW/cm2/nm, with a mean difference (SD) of 1.82 (3.81) μW/cm2/nm (P = 0.486).

Conclusions

In half of the hospitals that we studied on Java the levels of irradiance are too low and, in some cases, too high. Given the risks of insufficient phototherapy or adverse effects, we recommend that manufacturers provide radiometers so hospitals can optimize the performance of their phototherapy devices.

Electronic supplementary material

The online version of this article (10.1186/s12887-019-1552-1) contains supplementary material, which is available to authorized users.

Early cerebral and intestinal oxygenation in the risk assessment of necrotizing enterocolitis in preterm infants

BACKGROUND AND AIM

Predicting necrotizing enterocolitis (NEC) might help in preventing its devastating consequences. We aimed to investigate whether early cerebral and intestinal tissue oxygen saturation (rSO₂) and fractional tissue oxygen extraction (FTOE) predict the onset of NEC.

STUDY DESIGN

Prospective observational case-control study.

SUBJECTS

Infants with gestational age (GA) <32 weeks were included. For every NEC case we matched two controls based on GA, birth weight (BW), and a patent ductus arteriosus.

OUTCOME MEASURES

Cerebral oxygenation and intestinal oxygenation were prospectively monitored two-hours daily during the first five days after birth and once a week thereafter until five weeks after birth or until NEC developed. We used Kaplan-Meier analyses to determine the ability of near-infrared spectroscopy (NIRS) measurements, including their variability, to predict the development of NEC.

RESULTS

We included ten infants (median (range) GA 27.1 (24.6-29.4) weeks, BW 903 (560-1630) grams) who developed NEC at median postnatal day 13 (range: 4-43 days), and 20 matched controls. Infants with cerebral rSO₂ <70% within the first 48 h after birth developed NEC significantly more often than infants with cerebral rSO₂ ≥70% (odds ratio 9.00 (95% CI 1.33-61.14). Intestinal FTOE was higher in infants who developed NEC compared to controls during the last NIRS measurement at median 2 days (range: 1-7) before NEC onset (median 0.65 vs. 0.44).

CONCLUSIONS

Cerebral oxygenation monitoring early after birth might be valuable in the risk assessment of NEC development. Additionally, our results suggest that intestinal oxygenation is impaired before the onset of clinical NEC.

Dynamic prediction of bleeding risk in thrombocytopenic preterm neonates

Over 75% of severely thrombocytopenic neonates receive platelet transfusions, though little evidence supports this practice, and only 10% develop major bleeding. In a recent randomized trial, giving platelet transfusions at a threshold platelet count of 50x10⁹/L compared to a threshold of 25x10⁹/L was associated with an increased risk of major bleeding or mortality. This finding highlights the need for improved and individualized guidelines on neonatal platelet transfusion, which require accurate prediction of bleeding risk. Therefore, the objective of this study was to develop a dynamic prediction model for major bleeding in thrombocytopenic preterm neonates. This model allows for calculation of bleeding risk at any time-point during the first week after the onset of severe thrombocytopenia. In this multicenter cohort study, we included neonates with a gestational age <34 weeks, admitted to a neonatal intensive care unit, who developed severe thrombocytopenia (platelet count <50x10⁹/L). The study endpoint was major bleeding. We obtained predictions of bleeding risk using a proportional baselines landmark supermodel. Of 640 included neonates, 71 (11%) had a major bleed. We included the variables gestational age, postnatal age, intrauterine growth retardation, necrotizing enterocolitis, sepsis, platelet count and mechanical ventilation in the model. The median cross-validated c-index was 0.74 (interquartile range, 0.69-0.82). This is a promising dynamic prediction model for bleeding in this population that should be explored further in clinical studies as a potential instrument for supporting clinical decisions. The study was registered at www.clinicaltrials.gov (NCT03110887).

Risk Factors for Late-Onset Sepsis in Preterm Infants: A Multicenter Case-Control Study

BACKGROUND

Late-onset sepsis (LOS) in preterm infants is a leading cause of mortality and morbidity. Timely recognition and initiation of antibiotics are important factors for improved outcomes. Identification of risk factors could allow selection of infants at an increased risk for LOS.

OBJECTIVES

The aim was to identify risk factors for LOS.

METHODS

In this multicenter case-control study, preterm infants born at ≤30 weeks of gestation were included at 9 neonatal intensive care units. Detailed demographical and clinical data were collected daily up to day 28 postnatally. Clinical and demographic risk factors were identified using univariate and multivariate regression analyses in a 1: 1 matched case-control cohort.

RESULTS

In total, 755 infants were included, including 194 LOS cases (41 gram-negative cases, 152 gram-positive cases, and 1 fungus). In the case-control cohort, every additional day of parenteral feeding increased the risk for LOS (adjusted OR = 1.29; 95% CI 1.07-1.55; p = 0.006), whereas antibiotics administration decreased this risk (OR = 0.08; 95% CI 0.01-0.88; p = 0.039). These findings could largely be attributed to specific LOS-causative pathogens, since these predictive factors could be identified for gram-positive, but not for gram-negative, LOS cases. Specifically cephalosporins administration prior to clinical onset was inversely related to coagulase-negative staphylococcus LOS (CoNS-LOS) development. Formula feeding was an independent risk factor for development of CoNS-LOS (OR = 3.779; 95% CI 1.257-11.363; p = 0.018).

CONCLUSION

The length of parenteral feeding was associated with LOS, whereas breastmilk administration was protective against CoNS-LOS. A rapid advancement of enteral feeding, preferably with breastmilk, may proportionally reduce the number of parenteral feeding days and consequently the risk for LOS.

Adherence to hyperbilirubinemia guidelines by midwives, general practitioners, and pediatricians in Indonesia

Severe hyperbilirubinemia, which may result in kernicterus, is seen more frequently in low and middle-income countries, such as Indonesia, than in high-income countries. In Indonesia midwives, general practitioners (GPs), and pediatricians are involved in the care of jaundiced newborn infants. It is unknown whether the high incidence of severe hyperbilirubinemia in this country is related to a lack of awareness of existing hyperbilirubinemia guidelines issued by, for example, the World Health Organization, the American Academy of Pediatrics, or the Indonesian Health Ministry, or to a lack of adherence to such guidelines. The aim of this questionnaire study was to assess health professionals’ awareness of existing guidelines and their adherence to these guidelines in daily practice. We handed out a ten-question questionnaire to midwives, GPs, and pediatricians that included questions about the professionals themselves as well as clinical questions. The midwives completed 291 questionnaires, the GPs 206, and the pediatricians 154, all of which we used for our analysis. Almost 30% of the midwives and 23% of the GPs were either unaware of any existing guidelines or they did not adhere to them. Only 54% of the midwives recognized the warning signs of severe hyperbilirubinemia correctly, compared to 68% of the GPs and 89% of the pediatricians. Twenty-eight percent of the midwives and 31% of the GPs indicated that their first follow-up visit was after 72 hours, while 90% of them discharged infants after less than 48 hours after birth. The awareness of and adherence to guidelines for preventing and treating hyperbilirubinemia is low amongst the midwives and GPs in Indonesia. This may be an important contributing factor in the high incidence of severe hyperbilirubinemia in Indonesia.

Fecal Bile Salts and the Development of Necrotizing Enterocolitis in Preterm Infants

Background

Intestinal bile salts (BSs) may be implicated in NEC development. We hypothesized that fecal BS levels are higher in preterm infants at risk for NEC.

Methods

We compared the composition and concentration of fecal BSs in ten preterm infants who developed NEC (Bell’s Stage ≥ II) with twenty matched control infants without NEC. Conjugated and unconjugated fecal BSs were measured after birth (T1) and twice prior to NEC (T2, T3). Data are presented as medians and interquartile ranges.

Results

GA and BW were similar in all preterms: ~27⁺⁴ weeks and ~1010 g. Age of NEC onset was day 10 (8–24). T1 was collected 2 (1–3) days after birth. T2 and T3 were collected 5 (5–6) days and 1 (0–2) day before NEC or at corresponding postnatal ages in controls. The composition of conjugated BSs did not differ between the two groups. Total unconjugated BSs were 3-fold higher before NEC compared to controls at corresponding ages (0.41 μmol/g feces (0.21–0.74) versus 0.14 μmol/g feces (0.06–0.46), p < 0.05).

Conclusion

Fecal BS concentrations are higher in preterm infants who develop NEC compared to infants without NEC. Further study is needed to determine the predictive value of fecal BSs in the development of NEC.

The relation between splanchnic ischaemia and intestinal damage in necrotising enterocolitis

OBJECTIVES

The underlying pathophysiology of necrotising enterocolitis (NEC) remains incompletely understood, particularly the role of intestinal perfusion. We aimed to determine the relation between cerebral and splanchnic fractional tissue oxygen extraction (FTOE), a marker for tissue underperfusion, with intestinal fatty acid-binding protein in plasma (I-FABPp), a marker for intestinal damage, in infants with NEC. Furthermore, we investigated the combined courses of cerebral and splanchnic FTOE values and I-FABPp levels in uncomplicated (conservative treatment) and complicated NEC (surgery or death).

DESIGN

This study was part of a prospective observational cohort study.

PATIENTS

We included 19 preterm infants with NEC (9 uncomplicated, 10 complicated).

INTERVENTIONS

Using near-infrared spectroscopy, we measured regional cerebral and splanchnic tissue oxygen saturations continuously for 48 h after NEC onset. We measured I-FABPp levels simultaneously.

MAIN OUTCOME MEASURES

We used Spearman correlation tests to calculate correlation coefficients between FTOE values and I-FABPp levels in uncomplicated and complicated NEC.

RESULTS

Median (range) gestational age was 28 (25-36) weeks and median (range) birth weight was 1290 (740-2400) g. Cerebral and splanchnic FTOE values correlated strongly with I-FABPp levels (rho between .745 and 0.900; p<0.001-0.037) during the first 16 h after NEC onset. Thereafter, in uncomplicated NEC, splanchnic FTOE values increased while I-FABPp levels decreased concomitantly. In complicated NEC both splanchnic FTOE values and I-FABPp levels decreased.

CONCLUSIONS

Combining cerebral and splanchnic FTOE values with I-FABPp levels, gives insight in the pathological chain of events resulting in progression or recovery of intestinal ischaemia in NEC.

TRIAL REGISTRATION NUMBER

NTR3239.

The Ages and Stages Questionnaire and Neurodevelopmental Impairment in Two-Year-Old Preterm-Born Children

Objective

To test the ability of the Ages and Stages Questionnaire, Third Edition (ASQ3) to help identify or exclude neurodevelopmental impairment (NDI) in very preterm-born children at the corrected age of two.

Methods

We studied the test results of 224 children, born at <32 postmenstrual weeks, who had scores on ASQ3 and Bayley Scales of Infant and Toddler Development, Third Edition (BSIDIII) and neurological examination at 22–26 months’ corrected age. We defined NDI as a score of <70 on the cognitive—or motor composite scale of BSIDIII, or impairment on neurological examination or audiovisual screening. We compared NDI with abnormal ASQ3 scores, i.e., < -2SDs on any domain, and with ASQ3 total scores. To correct for possible overestimation of BSIDIII, we also analyzed the adjusted BSIDIII thresholds for NDI, i.e., scores <80 and <85.

Results

We found 61 (27%) children with abnormal ASQ3 scores, and 10 (4.5%) children who had NDI with original BSIDIII thresholds (<70). Twelve children had NDI at BSIDIII thresholds at <80, and 15 had <85. None of the 163 (73%) children who passed ASQ3 had NDI. The sensitivity of ASQ3 to detect NDI was excellent (100%), its specificity was acceptable (76%), and its negative predictive value (NPV) was 100%. Sensitivity and NPV remained high with the adjusted BSIDIII thresholds.

Conclusion

The Ages and Stages Questionnaire is a simple, valid and cost-effective screening tool to help identify and exclude NDI in very preterm-born children at the corrected age of two years.

Cerebral oxygenation is associated with neurodevelopmental outcome of preterm children at age 2 to 3 years

AIM

The aim of the study was to determine whether regional cerebral tissue oxygen saturation (r(c)SO2) and fractional tissue oxygen extraction (FTOE), using near-infrared spectroscopy, are associated with neurodevelopmental outcome of preterm infants.

METHOD

We measured rc SO2 on days 1, 2, 3, 4, 5, 8, and 15 after birth in 83 preterm infants (<32wks gestational age), and calculated FTOE=(SpO2 -r(c)SO2)/SpO2. Cognitive, motor, neurological, and behavioural outcomes were determined at 2 to 3 years using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III), an age-specific neurological examination, and the Child Behavior Checklist (CBCL) respectively. Multiple linear regression analyses were used to determine whether r(c)SO2 and FTOE contributed to outcome.

RESULTS

We followed up 67 infants. The lower quartile (P(25-50)) and highest quartile (P(75-100)) of r(c)SO2 on day 1 were associated with poorer cognitive outcome (p=0.044 and p=0.008 respectively). A lower area under the curve (AUC; over 15d) of r(c)SO2 was associated with poorer cognitive outcome (p=0.014). The lower quartile (P(25-50)) AUC of r(c)SO2 was associated with poorer fine motor outcome (p=0.004). The amount of time r(c)SO2 <50% on day 1 was negatively associated with gross motor outcome (p=0.002). The highest quartile of FTOE on day 1 was associated with poorer total motor outcome (p=0.041).

INTERPRETATION

Cerebral oxygen saturation during the first 2 weeks after birth is associated with neurodevelopmental outcome of preterm infants at 2 to 3 years. High and low r(c)SO2 on day 1 were associated with poorer neurodevelopmental outcome.

Intestinal fatty acid-binding protein as a diagnostic marker for complicated and uncomplicated necrotizing enterocolitis: a prospective cohort study

Background

Early NEC symptoms are non-specific and diagnostic tests lack discriminative power. Intestinal fatty acid-binding protein (I-FABP), mainly located in small bowel enterocytes, is released into the blood following NEC-associated enterocyte disruption. Aim of this prospective cohort trial was to determine the diagnostic value of I-FABP measured in plasma (I-FABPp) and urine (I-FABPu) for the presence of NEC, to evaluate I-FABP levels during NEC development, and to assess its prognostic value for the progression from suspected to complicated disease.

Methods

Between 2010 and 2012 we prospectively enrolled neonates with suspected NEC. We measured I-FABP levels eight-hourly from onset of suspected NEC for at least 48 hours, or until surgery. NEC diagnosis was confirmed radiologically or during operation. We defined NEC as complicated if it resulted in surgery and/or death. We determined disease course and diagnostic I-FABP cut-off points.

Results

The study comprised 37 neonates (24M, 13F), gestational age 28 (24–36) weeks, birth weight 1190 (570–2,400) grams. We found significantly higher I-FABPp and I-FABPu levels in NEC patients (n = 22) than in patients with other diagnoses (n = 15). Cut-off values for diagnosing NEC were 9 ng/mL I-FABPp and 218 ng/mL I-FABPu, with corresponding likelihood ratios (LRs) of 5.6 (95% CI 0.89–35) and 5.1 (95% CI 0.73–36), respectively. I-FABP levels were highest in the first eight hours after symptom onset and gradually decreased over time. Cut-off values for complicated disease were 19 ng/mL I-FABPp and 232 ng/mL I-FABPu, with LRs of 10 (95% CI 1.6–70) and 11 (95% CI 1.6–81), respectively.

Conclusions

Both plasma and urinary I-FABP levels specifically identify NEC in preterm infants prior to appearance of diagnostic radiological signs suggestive for NEC. Moreover, serial I-FABP measurements accurately predict development of complicated disease.

Bilirubin-albumin binding, bilirubin/albumin ratios, and free bilirubin levels: where do we stand?

Treatment for unconjugated hyperbilirubinemia is predominantly based on one parameter, i.e., total serum bilirubin (TSB) levels. Yet, overt kernicterus has been reported in preterm infants at relatively low TSB levels, and it has been repeatedly shown that free unconjugated bilirubin (freeUCB) levels, or bilirubin/albumin (B/A) ratios for that matter, are more closely associated with bilirubin neurotoxicity. In this article, we review bilirubin-albumin binding, UCBfree levels, and B/A ratios in addition to TSB levels to individualize and optimize treatment especially in preterm infants. Methods to measure bilirubin-albumin binding or UCBfree are neither routinely performed in Western clinical laboratories nor incorporated in current management guidelines on unconjugated hyperbilirubinemia. For bilirubin-albumin binding, this seems justified because several of these methods have been challenged, and sufficiently powered prospective trials on the clinical benefits are lacking. Technological advances in the measurement of UCBfree may provide a convenient means for integrating UCBfree measurements into routine clinical management of jaundiced infants. A point-of-care method, as well as determination of UCBfree levels in various newborn populations, is desirable to learn more about variations in time and how various clinical pathophysiological conditions affect UCBfree levels. This will improve the estimation of approximate UCBfree levels associated with neurotoxicity. To delineate the role of UCBfree in the management of jaundiced (preterm) infants, trials are needed using UCBfree as treatment parameter. The additional use of the B/A ratio in jaundiced preterms has been evaluated in the Bilirubin Albumin Ratio Trial (BARTrial; Clinical Trials: ISRCTN74465643) but failed to demonstrate better neurodevelopmental outcome in preterm infants <32 weeks assigned to the study group. Awaiting a study in which infants are assigned to be managed solely on the basis of their B/A ratio (with TSB excluded ) versus TSB levels alone-and determining which group does better-the additional use of the B/A ratio in the management of hyperbilirubinemia in preterms is not advised. In conjunction with TSB levels, other parameters possibly allow for more accurate prediction of bilirubin toxicity. Yet, different methodologies for estimating these parameters exist, and sufficiently powered, prospective clinical trials supporting their clinical benefit, i.e., reduced bilirubin neurotoxicity when using these parameters, are lacking. Their use in addition to TSB needs to be prospectively evaluated, especially in preterm neonates, and preferentially in randomized clinical trials, which include specific risk factors and assessment of clinical relevant outcome measures for detecting those infants at risk of bilirubin toxicity.

Cytokines patterns in newborn infants with late onset sepsis

BACKGROUND

Cytokines might be helpful to diagnose late onset sepsis (LOS) in newborn infants. Many studies on cytokines did not discriminate culture-proven from clinically-suspected sepsis; however, such differentiation is clinically useful.

OBJECTIVES

To evaluate the feasibility to differentiate among culture-proven LOS, clinical LOS and controls using a battery of cytokines.

STUDY DESIGN

This prospective study was conducted at the NICU of Harapan-Kita Women and Children's Hospital, Jakarta-Indonesia. Three groups of infants with postnatal age >72 hours of age were enrolled in the study: culture-proven sepsis group (PS) (n = 18), clinical sepsis group (CS) (n = 25) and control group (n = 34). A battery of 25 cytokines was measured in each infant five times: at enrollment, after 4 hrs, 12 hrs, 24 hrs, and 48 hrs using Invitrogen-immunoassays-Luminex™100.

RESULTS

There were no significant differences in gestational age or mode of delivery among the three groups. IL-1β, IL-2r, IL-6, IL-8, IL-10 and MIP-1a were significantly higher at all measurement points in group PS compared to controls. IL-13 was lower at all measurement moments in group CS compared to controls, IL-12 was lower and IP-10 higher between 0 and 24 hrs. IL-1Ra, IL-6, IL-8, IL-13, IL-15, TNFα, MIP-1a and MIP-1b were higher at all the measurement moments in group PS compared to group CS. The ROC curves show that IL-6, IL-8, IL-15, MIP-1a, MIP-1b and TNFα have a sensitivity and specificity between 80 and 85% during the first 24-48 hours after the onset of infection. IL-6, IL-15, MIP-1a, MIP-1b and TNFα showed the best likelihood ratios.

CONCLUSIONS

IL-6, IL8, IL 15, MIP-1a, MIP-1b and TNFα are potentially good markers for detecting a proven LOS. In case these cytokines are not elevated in sick infants, other causes than an infection have to be identified.

The bilirubin albumin ratio in the management of hyperbilirubinemia in preterm infants to improve neurodevelopmental outcome: a randomized controlled trial--BARTrial

Background and Objective

High bilirubin/albumin (B/A) ratios increase the risk of bilirubin neurotoxicity. The B/A ratio may be a valuable measure, in addition to the total serum bilirubin (TSB), in the management of hyperbilirubinemia. We aimed to assess whether the additional use of B/A ratios in the management of hyperbilirubinemia in preterm infants improved neurodevelopmental outcome.

Methods

In a prospective, randomized controlled trial, 615 preterm infants of 32 weeks' gestation or less were randomly assigned to treatment based on either B/A ratio and TSB thresholds (consensus-based), whichever threshold was crossed first, or on the TSB thresholds only. The primary outcome was neurodevelopment at 18 to 24 months' corrected age as assessed with the Bayley Scales of Infant Development III by investigators unaware of treatment allocation. Secondary outcomes included complications of preterm birth and death.

Results

Composite motor (100±13 vs. 101±12) and cognitive (101±12 vs. 101±11) scores did not differ between the B/A ratio and TSB groups. Demographic characteristics, maximal TSB levels, B/A ratios, and other secondary outcomes were similar. The rates of death and/or severe neurodevelopmental impairment for the B/A ratio versus TSB groups were 15.4% versus 15.5% (P = 1.0) and 2.8% versus 1.4% (P = 0.62) for birth weights ≤1000 g and 1.8% versus 5.8% (P = 0.03) and 4.1% versus 2.0% (P = 0.26) for birth weights of >1000 g.

Conclusions

The additional use of B/A ratio in the management of hyperbilirubinemia in preterm infants did not improve their neurodevelopmental outcome.

Trial Registration

Controlled-Trials.com ISRCTN74465643

Clinical importance of a fixed bowel loop in the treatment of necrotizing enterocolitis

BACKGROUND

The need for surgical treatment in neonates with necrotizing enterocolitis (NEC) is associated with high mortality. Although pneumoperitoneum and progressive disease are generally accepted indications for surgery, it is unclear whether a fixed bowel loop (FBL) should prompt surgery.

OBJECTIVE

To determine the relationship between an FBL, type of treatment, and death in the management of NEC.

METHODS

Retrospective analysis (January 2000-December 2011) of all neonates with definite NEC in a tertiary neonatal intensive care unit. FBL was defined as a persistent (i.e. >24 h) dilated intestinal segment present on serial abdominal X-rays.

RESULTS

NEC was diagnosed in 141 neonates (median gestational age 30 weeks; median birth weight 1,340 g). An FBL was reported in 38 (27%) patients, of whom 18 were treated surgically. Mortality among FBL patients was independent of the type of treatment (surgical versus conservative): 8/18 and 7/20, respectively (p = 0.55). Of the 103 patients without FBL, 37 (36%) were treated surgically, which is comparable to the FBL group. Again, mortality was not related to the type of treatment (surgical versus conservative): 5/37 and 6/66, respectively (p = 0.49). The presence of an FBL was associated with mortality: more patients with an FBL (15/38, 39%) died than without an FBL (11/103, 11%; odds ratio 5.45, 95% confidence interval 2.21-13.45; p < 0.01).

CONCLUSIONS

In NEC patients, an FBL is associated with increased mortality. On its own it has moderate significance to guide treatment. Nevertheless, because it reflects disease severity, early recognition is important and prompt (surgical) treatment should be considered.

Intestinal fatty acid-binding protein in neonates with imminent necrotizing enterocolitis

BACKGROUND

Intestinal fatty acid-binding protein (I-FABP) is a promising marker for necrotizing enterocolitis (NEC). It can be measured in plasma (I-FABPp) and urine (I-FABPu). Data on the best way to measure I-FABP (in plasma or urine) and the necessity of simultaneous measurement of the urinary creatinine concentration to correct for physiological variations in urine concentration are not available. This holds also true for the reciprocal relation between I-FABPp, I-FABPu and other more conventional laboratory parameters.

OBJECTIVES

To evaluate the above-mentioned correlations of I-FABP measurements in neonates with suspected NEC.

METHODS

All neonates with suspected NEC were prospectively included. I-FABPp and I-FABPu were analyzed at regular intervals during the first 24 h after onset of symptoms. Correlation and agreement were assessed between these and other parameters (i.e., IL-6, WBC, platelet count, CRP, pH and lactate).

RESULTS

Included were 24 boys, 13 girls [median (range) GA 28 weeks (24-36), median birth weight 1,190 g (570-2,400)]. I-FABPu correlated strongly with I-FABPp (r 0.80, p < 0.001) with an adequate agreement. A very strong correlation between I-FABPu and I-FABPu/urine creatinine ratio (r 0.98, p < 0.001) existed. Correlations between I-FABPp/u and conventional parameters were moderate to strong until 8 h after onset of symptoms.

CONCLUSION

In neonates with suspected NEC, I-FABPu correlates strongly with I-FABPp, offering an opportunity to choose the most appropriate way of measuring I-FABP. Calculating urinary IFABP/creatinine ratio seems redundant. Moderately strong correlations between I-FABPu and IL-6, WBC and lactate were found.

Levels of 25 cytokines in the first seven days of life in newborn infants

BACKGROUND

Novel methods for cytokine analysis allow for the simultaneous measurement of 25 cytokines in 50 μL serum or plasma. Data on values of most of these cytokines in non-infected newborn infants are lacking. We analyzed levels of 25 cytokines in the first week of life in non-infected preterm and term infants and related them to gestational age.

FINDINGS

During the first week after birth, no trend over time was found in any of the cytokines, except for IL-1Ra and IL-6 where higher values were found in the first four hours. Between 24 and 72 hrs levels of IL-1Ra, IL-2, IL-8, IL-12, IL-13, IL-15, IL-17, IFNγ, MIP-1a, MCP-1, TNFα were lower in infants born after 30-32 wks compared to infants ≥ 36 wks; levels of IL-6, IL-10, IP-10 were lower in preterm infants of both 30-32 and 33-36 weeks. No difference between groups for any of the levels was found for IL-1b, IL-2r, IL-4, IL-5, IL-7, IFNa, MIP-1b, GM-CSF, Eotaxin and RANTES.

CONCLUSIONS

Levels of 25 interleukines are stable in the first week of life in non-infected infants. Infants born after 30-32 wks showed lower levels of fourteen cytokines compared to infants born after more then 36 wks. This indicates a lower stimulation or activation of Th-1 cells, monocytes and dendritic cells in these infants.

Optimizing exchange transfusion for severe unconjugated hyperbilirubinemia: studies in the Gunn rat

Background

Severe unconjugated hyperbilirubinemia carries the risk of neurotoxicity. Phototherapy (PT) and exchange transfusion (ET) are cornerstones in the treatment of unconjugated hyperbilirubinemia. Studies to improve ET efficacy have been hampered by the low application of ET in humans and by the lack of an in vivo model. The absence of an appropriate animal model has also prevented to determine the efficacy of adjunct or alternative treatment options such as albumin (Alb) administration.

Aim

To establish an in vivo model for ET and to determine the most effective treatment (combination) of ET, PT and Alb administration.

Methods

Gunn rats received either PT, PT+Alb, ET, ET+PT, ET+PT+Alb or sham operation (each n = 7). ET was performed via the right jugular vein in ∼20 min. PT (18 µW/cm²/nm) was started after ET or at T₀. Albumin i.p. injections (2.5 g/kg) were given after ET or before starting PT. Plasma unconjugated bilirubin (UCB), plasma free bilirubin (Bf), and brain bilirubin concentrations were determined.

Results

We performed ET in 21 Gunn rats with 100% survival. At T₁, ET was profoundly more effective in decreasing both UCB −44%, p<0.01) and Bf −81%, p<0.05) than either PT or PT+Alb. After 48 h, the combination of ET+PT+Alb showed the strongest hypobilirubinemic effect (−54% compared to ET).

Conclusions

We optimized ET for severe unconjugated hyperbilirubinemia in the Gunn rat model. Our data indicate that ET is the most effective treatment option, in the acute as well as the follow-up situation.

Evaluation of treatment thresholds for unconjugated hyperbilirubinemia in preterm infants: effects on serum bilirubin and on hearing loss?

Background

Severe unconjugated hyperbilirubinemia may cause deafness. In the Netherlands, 25% lower total serum bilirubin (TSB) treatment thresholds were recently implemented for preterm infants.

Objective

To determine the rate of hearing loss in jaundiced preterms treated at high or at low TSB thresholds.

Design/Methods

In this retrospective study conducted at two neonatal intensive care units in the Netherlands, we included preterms (gestational age <32 weeks) treated for unconjugated hyperbilirubinemia at high or low TSB thresholds. Infants with major congenital malformations, syndromes, chromosomal abnormalities or toxoplasmosis, rubella, cytomegalovirus, herpes, syphilis, and human immunodeficiency infections were excluded. We analyzed clinical characteristics and TSB levels during the first ten postnatal days. After two failed automated Auditory Brainstem Response (ABR) tests we used the results of the diagnostic ABR examination to define normal, unilateral, and bilateral hearing loss (>35 dB).

Results

There were 479 patients in the high and 144 in the low threshold group. Both groups had similar gestational ages (29.5 weeks) and birth weights (1300 g). Mean and mean peak TSB levels were significantly lower after the implementation of the novel thresholds: 152±43 µmol/L and 212±52 µmol/L versus 131±37 µmol/L and 188±46 µmol/L for the high versus low thresholds, respectively (P<0.001). The incidence of hearing loss was 2.7% (13/479) in the high and 0.7% (1/144) in the low TSB threshold group (NNT = 50, 95% CI, 25–3302).

Conclusions

Implementation of lower treatment thresholds resulted in reduced mean and peak TSB levels. The incidence of hearing impairment in preterms with a gestational age <32 weeks treated at low TSB thresholds was substantially lower compared to preterms treated at high TSB thresholds. Further research with larger sample sizes and power is needed to determine if this effect is statistically significant.

High variability and low irradiance of phototherapy devices in Dutch NICUs

OBJECTIVE

To evaluate phototherapy practices by measuring the irradiance levels of phototherapy (PT) devices.

DESIGN

Prospective study.

SETTING

Tertiary neonatal intensive care units.

PATIENTS

None.

INTERVENTIONS

Irradiance levels of PT devices used in the 10 Dutch Neonatal Intensive Care Units (NICUs) were measured according to the local PT practice patterns. The irradiance levels of all overhead and fibre-optic PT devices were measured with a radiometer using an infant silhouette model.

RESULTS

Eight different PT devices were used in the 10 NICUs; five were overhead devices and three fibre-optic pads. The median (range) irradiance level for overhead PT devices was 9.7 (4.3-32.6) µW/cm(2)/nm and for fibre-optic pads 6.8 (0.8-15.6) µW/cm(2)/nm. Approximately 50% of PT devices failed to meet the minimal recommended irradiance level of 10 µW/cm(2)/nm. Maximal irradiance levels for overhead PT spot lights were inversely related to the distance between device and infant model (R2=0.33). The distances ranged from 37 cm to 65 cm.

CONCLUSIONS

PT devices in the Dutch NICUs show considerable variability with often too low irradiance levels. These results indicate that suboptimal PT is frequently applied and may even be ineffective towards reducing total serum bilirubin levels. These results underline the need for greater awareness among all healthcare workers towards the requirements for effective PT including measurements of irradiance and distance.

Beyond plasma bilirubin: the effects of phototherapy and albumin on brain bilirubin levels in Gunn rats

BACKGROUND & AIMS

Severe unconjugated hyperbilirubinemia, as occurs in Crigler-Najjar disease and neonatal jaundice, carries the risk of neurotoxicity. This neurotoxicity is related to the increased passage of free bilirubin (UCB(free)), the fraction of bilirubin that is not bound to plasma proteins, into the brain. We hypothesized that albumin treatment would lower the UCB(free) fraction, and thus decrease bilirubin accumulation in the brain.

METHODS

We treated chronic (e.g., as a model for Crigler-Najjar disease) and acute hemolytic (e.g., as a model for neonatal jaundice) moderate hyperbilirubinemic Gunn rats with phototherapy, human serum albumin (HSA) or phototherapy+HSA.

RESULTS

In the chronic model, adjunct HSA increased the efficacy of phototherapy; it decreased plasma UCB(free) and brain bilirubin by 88% and 67%, respectively (p<0.001). In the acute model, adjunct HSA also increased the efficacy of phototherapy; it decreased plasma UCB(free) by 76% (p<0.001) and completely prevented the hemolysis-induced deposition of bilirubin in the brain. Phototherapy alone failed to prevent the deposition of bilirubin in the brain during acute hemolytic jaundice.

CONCLUSIONS

We showed that adjunct HSA treatment decreases brain bilirubin levels in phototherapy-treated Gunn rats. We hypothesize that HSA decreases these levels by lowering UCB(free) in the plasma. Our results support the feasibility of adjunct albumin treatment in patients with Crigler-Najjar disease or neonatal jaundice.

Severe neonatal hyperbilirubinemia in the Netherlands

BACKGROUND

The occurrence of severe neonatal hyperbilirubinemia (SH) is partly attributed to nonhospitalized perinatal care. The Netherlands have a high frequency of home births and nonhospitalized perinatal care, and the incidence of SH is unknown.

OBJECTIVE

To assess the effects of home births and early hospital discharge on the incidence of SH in term-born infants in the Netherlands.

METHODS

In this nationwide prospective surveillance study between 2005 and 2009, infants (≥37 weeks GA) were included if total serum bilirubin (TSB) was ≥500 µmol/l or if they received an exchange transfusion when TSB was ≥340 µmol/l.

RESULTS

Seventy-one infants had SH (incidence 10.4/100,000); 43 had a TSB ≥500 μmol/l (incidence 6.3/100,000) and 45 (63%) underwent an exchange transfusion. 26% of the infants with SH were born at home, which is similar to 22% of all term infants who are born at home in the Netherlands (p = 0.41). Maximum TSB levels were similar in infants born at home (523 ± 114 μmol/l) and infants born in hospital (510 ± 123 μmol/l; p = 0.70). Of the 51 infants born in hospital, 33 were discharged and readmitted with SH, with maximal TSB levels (567 ± 114 μmol/l), which were higher than in infants who remained hospitalized (406 ± 47 μmol/l; p = 0.0001).

CONCLUSION

The incidence of severe hyperbilirubinemia in term-born infants in the Netherlands is 10.4 per 100,000, which is similar to other developed countries. Home birth and early hospital discharge do not necessarily lead to a higher incidence of SH, provided that perinatal home care is well organized.

Thrombocytopaenia and intraventricular haemorrhage in very premature infants: a tale of two cities

OBJECTIVE

To study whether the incidence of intraventricular haemorrhage (IVH) in very premature infants (<32 weeks gestation) with thrombocytopaenia is lower when using a liberal platelet-transfusion guideline compared with a restrictive guideline.

STUDY DESIGN

A retrospective cohort study comparing the incidence of IVH in very premature infants with thrombocytopaenia (platelet count <150×10(9)/l) admitted between 2007 and 2008 to two neonatal intensive care unit in The Netherlands. The restrictive platelet-transfusion unit (N=353 infants <32 weeks gestation) transfused only in case of active haemorrhage and a platelet count <50×10(9)/l. The liberal-transfusion unit (N=326 infants <32 weeks gestation) transfused according to predefined platelet count thresholds. Primary outcome was the incidence and severity of IVH in infants with thrombocytopaenia in both units.

RESULTS

The number of infants with thrombocytopaenia that received a platelet transfusion was significantly lower in the restrictive-transfusion unit compared with the liberal-transfusion unit, 15% (21/145) versus 31% (41/141), (p<0.001). The incidence of IVH in infants with thrombocytopaenia in the restrictive-transfusion and liberal-transfusion units was 30% (44/145) and 29% (41/141), respectively (p=0.81). The incidence of severe IVH (grade 3 or 4) in the restrictive-transfusion and liberal-transfusion units was 8% (12/145) and 11% (16/141), respectively (p=0.38).

CONCLUSION

In the restrictive-transfusion unit, the rate of platelet transfusions was significantly lower, but the incidence and severity of IVH was similar to the liberal-transfusion unit.

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.

Moderate unconjugated hyperbilirubinemia causes a transient but delayed suppression of amplitude-integrated electroencephalographic activity in preterm infants

BACKGROUND

Unconjugated hyperbilirubinemia occurs frequently in preterm infants and may result in bilirubin encephalopathy. Amplitude-integrated electroencephalography (aEEG) is used to evaluate brain function in newborns.

OBJECTIVES

To investigate the influence of total serum bilirubin (TSB) on the aEEG amplitude of preterm infants and to evaluate aEEG as a noninvasive method to identify acute bilirubin encephalopathy.

METHODS

We performed a prospective observational study of 34 infants with a gestational age (GA) of 26-31 6/7 weeks. Infants had aEEG recordings on the 1st-5th, 8th and 15th day after birth. Infants with asphyxia, intraventricular hemorrhage >grade I or circulatory insufficiency were excluded. aEEG was evaluated by calculating the mean 5th, 50th and 95th centiles of the aEEG amplitudes.

RESULTS

TSB peaked on the 4th day after birth. There was no synchronous relationship between TSB and aEEG amplitudes. The 5th, 50th, and 95th aEEG amplitude centiles on the 8th day correlated negatively with the TSB peak value (r = -0.37, p = 0.048; r = -0.60, p = 0.001; r = -0.44, p = 0.017, respectively), irrespective of GA. The 5th and 50th aEEG amplitude centiles increased with increasing GA (r = 0.45, p < 0.001, and r = 0.26, p < 0.001, respectively) and postnatal age (r = 0.25, p < 0.001, and r = 0.16, p = 0.023, respectively).

CONCLUSIONS

TSB had no direct effect on aEEG amplitudes in preterm infants. There is, however, a delayed effect on electrocerebral activity in the 2nd week after birth.

Early corticosteroid treatment does not affect severity of unconjugated hyperbilirubinemia in extreme low birth weight preterm infants

AIM

To determine the relationship between early postnatal dexamethasone (DXM) treatment and the severity of hyperbilirubinemia in extreme low birth weight (ELBW) preterm infants.

METHODS

In 54 ELBW preterm infants, total serum bilirubin concentrations (TSB) and phototherapy (PT) data during the first 10 days were evaluated retrospectively. ELBW infants had participated in a randomized controlled trial of early DXM treatment which aimed to assess effects on chronic lung disease. Infants had been treated with DXM (0.25 mg/kg twice daily at postnatal day 1 and 2) or with placebo (normal saline). Analysis was performed on an intention to treat basis.

RESULTS

Twenty-five Infants had been randomized into the DXM group; 29 into the placebo group. Mean (±SD) TSB [120 (±19) μmol/L vs. 123 (±28) μmol/L, DXM versus placebo, respectively] and maximum TSB [178 (±23) μmol/L vs. 176 (±48), DXM versus placebo, respectively] concentrations were similar. TSB concentrations peaked 30 h earlier in the DXM group (p ≤ 0.05). The need for PT as well as the duration of PT was similar in both groups.

CONCLUSIONS

Early DXM treatment does not affect the severity of neonatal hyperbilirubinemia in ELBW preterm infants. Our results seem compatible with the concept that factors other than bilirubin conjugation capacity are important for the pathophysiology of neonatal jaundice in ELBW preterm infants.

Measurements of neonatal bilirubin and albumin concentrations: a need for improvement and quality control

Accurate and precise bilirubin and albumin measurements are essential for proper management of jaundiced neonates. Data hereon are lacking for Dutch laboratories. We aimed to determine variability of measurements of bilirubin and albumin concentrations typical for (preterm) neonates. Aqueous, human serum albumin-based samples with different concentrations of bilirubin (100, 200, 300, 400, and 500 μmol/L) and albumin (0, 10, 15, 20, 25, and 30 g/L) were sent to laboratories of all Dutch neonatal intensive care units (n = 10). Bilirubin and albumin recoveries of the specimens were measured using locally available routine analytical methods. The mean, standard deviation, and coefficients of variations (CV) were calculated per sample. Bilirubin concentrations were underestimated in the absence of albumin (maximal CV 26.0%). When the albumin concentration was 10 or 20 g/L, the bilirubin concentrations of the samples were overestimated (maximal CV 14.1% and 9.2%, respectively). Variability increased with higher weighed-in bilirubin concentrations. Measured albumin levels were ~10% lower than albumin levels of manufactured samples. Bilirubin concentration did not influence albumin measurements. The maximal CV was 6.8%. In conclusion, interlaboratory variability of bilirubin and albumin measurements is high. Recalibration and introduction of a specific quality assessment scheme for neonatal samples is recommended to ensure exchangeability of bilirubin and albumin measurements among laboratories and to control the observed large variability.

[Uniform intervention criteria for jaundice in hyperbilirubinemia in preterm infants]

OBJECTIVE

To compare the guidelines of the 10 Dutch neonatal intensive care units (NICUs) for the treatment of preterm infants with hyperbilirubinemia, in order to develop uniform threshold levels for the total serum concentration of bilirubin (TSB) above which treatment with phototherapy or exchange transfusion is indicated.

DESIGN

Survey.

METHODS

Guidelines for hyperbilirubinemia in preterm infants (gestational age < 32 weeks) from all 10 Dutch NICUs were obtained and compared with each other and with international guidelines.

RESULTS

All 10 NICUs used intervention criteria based on TSB. 9 NICUs used TSB thresholds based on birth weight (1 used gestational age) with 2, 3 or 5 categories. 6 NICUs used age-specific TSB thresholds and 4 NICUs used a constant TSB threshold. The maximum range in TSB thresholds was 170 micromol/l for phototherapy and 125 micromol/l for exchange transfusion. Acidosis, sepsis, asphyxia, active haemolysis and intraventricular haemorrhage were the risk factors most frequently used. During a consensus meeting with representatives of the 10 NICUs, a guideline was agreed upon that will now be used for all neonates with a gestational age < 35 weeks.

CONCLUSION

There was considerable variation in the TSB thresholds used to date by the 10 NICUs. Now in the Netherlands, in addition to guideline 'Hyperbilirubinemia' for children with a gestational age >or= 35 weeks, 'uniform yellow thresholds' shall be used for jaundiced preterm infants with a gestational age < 35 weeks.

Usefulness of the bilirubin/albumin ratio for predicting bilirubin-induced neurotoxicity in premature infants

Unconjugated hyperbilirubinaemia occurs in almost all premature infants and is potentially neurotoxic. Treatment is based on total serum bilirubin (TSB), but treatment thresholds are not evidence based. Free bilirubin (Bf)-that is, not bound to albumin, seems a better parameter for bilirubin neurotoxicity, but measurements of Bf are not available in clinical practice. The bilirubin/albumin (B/A) ratio is considered a surrogate parameter for Bf and an interesting additional parameter in the management of hyperbilirubinaemia. This paper reviewed the evidence supporting the use of B/A ratios for predicting bilirubin-induced neurological dysfunction (BIND) including neurodevelopmental delay in jaundiced premature infants (gestational age less than 32 weeks). A literature search was performed and six publications reviewed regarding B/A ratios in the management and outcome of jaundiced premature infants. No prospective clinical trials had been undertaken to show whether bilirubin-induced neurotoxicity is reduced or whether unnecessary treatment is avoided by using the B/A ratio in addition to TSB. Recently, a randomised controlled trial evaluating the effect of the additional use of the B/A ratio on neurodevelopmental outcome in jaundiced premature infants has been initiated. Based on the prevailing evidence many authorities suggest that the additional use of the B/A ratio may be valuable when evaluating jaundiced premature infants.