Acute management of extreme neonatal jaundice--the potential benefits of intensified phototherapy and interruption of enterohepatic bilirubin circulation

Can exchange transfusion be replaced by double-LED phototherapy?

Phototherapy is a conventional treatment for neonatal jaundice and widely considered as a safe procedure. Recent developments in light-emitting diode (LED) phototherapy devices have made more effective treatments possible. Exchange transfusion (ET) is typically applied for cases of refractory severe hyperbilirubinemia despite its risk of various complications. Since the therapeutic effect of phototherapy is correlated with its irradiance, ET may be avoided by performing phototherapy with higher irradiation. Recently, we adopted double-LED phototherapy as a bridging treatment to ET to treat a case of severe hyperbilirubinemia. In this case, the continual increase of bilirubin levels was suppressed immediately after its administration, and ET was not required. Throughout the treatment, no complications or increase in oxidative stress was observed. In addition, neurodevelopment was appropriate for the patient’s age at the 1-year follow-up, and no findings of kernicterus, including physical and magnetic resonance imaging findings, were observed. We hypothesized that double-LED phototherapy may be a good treatment strategy to replace ET for infants with severe hyperbilirubinemia; however, further investigations regarding safety issues including acute and long-term complications are needed before clinical adaptation.

Home phototherapy for hyperbilirubinemia in term neonates-an unblinded multicentre randomized controlled trial

The aim of this study was to assess whether home phototherapy was feasible and safe in a cohort of otherwise healthy term-born neonates who fulfilled the criteria for in-hospital phototherapy. This was a randomized controlled trial in which term newborns with a total serum bilirubin of 18-24 mg/dL (300-400 μmol) were randomized to either home phototherapy or conventional in-hospital phototherapy. The primary outcome measurements were safety and efficacy, length of stay and the number of failed treatments. The secondary outcomes were the number of blood samples and weight gain during treatment. One hundred forty-seven patients were recruited, 69 patients randomized to conventional phototherapy and 78 to home phototherapy. The results showed that no patients needed blood exchange and only 4% of the patients allocated to home phototherapy were admitted to the hospital. The duration of phototherapy, length of stay, amount of blood tests and weight change showed no statically significant differences.Conclusion: Home phototherapy could be a safe alternative to inpatient phototherapy for otherwise healthy newborns with hyperbilirubinemia if daily checkups and 24/7 telephone support can be provided. The parents should be informed to contact the hospital immediately if they fail to perform the treatment at home.Trial registration: Clinicaltrials.gov NCT03536078 What is Known: • Phototherapy in the hospital is a safe and effective treatment without major side effects. • Fibre optic equipment has made the choice of home phototherapy possible. What is New: • This is the first randomized controlled trial comparing home phototherapy with hospital phototherapy. • Results indicate that home phototherapy could be considered as a safe and feasible alternative when performed according to instructions given, to hospital treatment for otherwise healthy term newborns.

Efficacy of oral agar in management of indirect hyperbilirubinemia in full-term neonates

Aim: This prospective randomized case control study aimed to investigate effect of oral agar administration in reducing total serum bilirubin (TSB) levels in full-term neonates with jaundice in comparison with control.Materials and methods: One hundred sixty full-term neonates were enrolled with TSB 10-19 mg/dl at first week of age from Assiut University Children's Hospital. Neonates were divided according to TSB into outpatient group (n = 100) (TSB 10-15 mg/dl) and admitted group (n = 60) (TSB > 15-19 mg/dl). Outpatients group were subdivided into agar group received oral agar and control group received placebo. Admitted group were subdivided into agar group received oral agar plus phototherapy combination and control group received phototherapy alone. Neonates in the agar supplementation received oral agar 600 mg/kg/day dissolved in 10 ml distilled water twice daily till TSB decreased to 7 mg/dl. Daily weight, stool frequency and side effects of treatment were observed for each group. TSB was determined pretreatment then serially every 48 h until TSB level reaching ≤7 mg/dl.Results: Agar fed was effective in lowering TSB in neonates with TSB 10-15 mg/dl. TSB percentage changes were not significantly lower in agar-fed newborn with TSB >15-19 mg/dl compared with control groups after 24 h and 7 days. Age fed shortened the time required to decrease TSB and increased stooling frequency.Conclusions: Oral agar supplemented feeding at 600 mg/kg/day is safe for full-term neonates and useful in decreasing TSB and phototherapy duration. The efficacy of phototherapy in decreasing TSB level in neonatal hyperbilirubinemia can be augmented with oral agar usage.

Extreme neonatal hyperbilirubinemia and kernicterus spectrum disorder in Denmark during the years 2000-2015

OBJECTIVE

To determine the incidence and etiology of extreme neonatal hyperbilirubinemia, defined as total serum bilirubin (TSB) ≥450 µmol/L, and kernicterus spectrum disorder (KSD) in Denmark between 2000 and 2015.

STUDY DESIGN

We identified all infants born between 01.01.2000 and 31.12.2015 with TSB ≥450 µmol/L, ratio of conjugated to TSB <0.30, gestational age ≥35 weeks, and postnatal age ≤4 weeks, using Danish hospitals' laboratory databases.

RESULT

We included 408 infants. The incidence of extreme neonatal hyperbilirubinemia among infants with gestational age ≥35 weeks was 42/100,000 during the study period with a seemingly decreasing incidence between 2005 and 2015. Twelve of the 408 infants developed KSD, (incidence 1.2/100,000) Blood type ABO isohemolytic disease was the most common explanatory etiology.

CONCLUSIONS

Our study stresses the importance of a systematic approach to neonatal jaundice and ongoing surveillance of extreme neonatal hyperbilirubinemia and KSD.

Review of bilirubin neurotoxicity II: preventing and treating acute bilirubin encephalopathy and kernicterus spectrum disorders

Previously in Part I of this two-part review, we discussed the current and recent advances in the understanding of the molecular biology and neuropathology of bilirubin neurotoxicity (BNTx). Here in Part II, we summarize current treatment options available to treat the severely jaundiced infants to prevent significant brain damage and improve clinical outcomes. In addition, we review potential novel therapies that are in various stages of research and development. We will emphasize treatments for both prevention and treatment of both acute bilirubin encephalopathy (ABE) and kernicterus spectrum disorders (KSDs), highlighting the treatment of the most disabling neurological sequelae of children with mild-to-severe KSDs whose "rare disease" status often means they are overlooked by the clinical research community at large. As with other secondary dystonias, treatment of the dystonic motor symptoms in kernicterus is the greatest clinical challenge.

Rates of Extreme Neonatal Hyperbilirubinemia and Kernicterus in Children and Adherence to National Guidelines for Screening, Diagnosis, and Treatment in Sweden

IMPORTANCE

Neonatal hyperbilirubinemia can cause lifelong neurodevelopmental impairment (kernicterus) even in high-resource settings. A better understanding of the incidence and processes leading to kernicterus may help in the design of preventive measures.

OBJECTIVES

To determine incidence rates of hazardous hyperbilirubinemia and kernicterus among near-term to term newborns and to evaluate health care professional adherence to best practices.

DESIGN, SETTING, AND PARTICIPANTS

This population-based nationwide cohort study used prospectively collected data on the highest serum bilirubin level for all infants born alive at 35 weeks' gestation or longer and admitted to neonatal care at all 46 delivery and 37 neonatal units in Sweden from 2008 to 2016. Medical records for newborns with hazardous hyperbilirubinemia were evaluated for best neonatal practices and for a diagnosis of kernicterus up to 2 years of age. Data analyses were performed between September 2017 and February 2018.

EXPOSURES

Extreme (serum bilirubin levels, 25.0-29.9 mg/dL [425-509 μmol/L]) and hazardous (serum bilirubin levels, ≥30.0 mg/dL [≥510 μmol/L]) neonatal hyperbilirubinemia.

MAIN OUTCOMES AND MEASURES

The primary outcome was kernicterus, defined as hazardous neonatal hyperbilirubinemia followed by cerebral palsy, sensorineural hearing loss, gaze paralysis, or neurodevelopmental retardation. Secondary outcomes were health care professional adherence to national guidelines using a predefined protocol with 10 key performance indicators for diagnosis and treatment as well as assessment of whether bilirubin-associated brain damage might have been avoidable.

RESULTS

Among 992 378 live-born infants (958 051 term births and 34 327 near-term births), 494 (320 boys; mean [SD] birth weight, 3505 [527] g) developed extreme hyperbilirubinemia (50 per 100 000 infants), 6.8 per 100 000 infants developed hazardous hyperbilirubinemia, and 1.3 per 100 000 infants developed kernicterus. Among 13 children developing kernicterus, brain injury was assessed as potentially avoidable for 11 children based on the presence of 1 or several of the following possible causes: untimely or lack of predischarge bilirubin screening (n = 6), misinterpretation of bilirubin values (n = 2), untimely or delayed initiation of treatment with intensive phototherapy (n = 1), untimely or no treatment with exchange transfusion (n = 6), or lack of repeated exchange transfusions despite indication (n = 1).

CONCLUSIONS AND RELEVANCE

Hazardous hyperbilirubinemia in near-term or term newborns still occurs in Sweden and was associated with disabling brain damage in 13 per million births. For most of these cases, health care professional noncompliance with best practices was identified, suggesting that a substantial proportion of these cases might have been avoided.

Bilirubin binding in jaundiced newborns: from bench to bedside?

BACKGROUND

Bilirubin-induced neurologic dysfunction (BIND) is a spectrum of preventable neurological sequelae in jaundiced newborns. Current total plasma bilirubin (B_T) concentration thresholds for phototherapy and/or exchange transfusion poorly predict BIND.

METHODS

The unbound (free) bilirubin (B_f) measured at these B_T thresholds provides additional information about the risk for BIND. B_f can be readily adapted to clinical use by determining B_f population parameters at current B_T thresholds. These parameters can be established using a plasma bilirubin binding panel (BBP) consisting of B_T, B_f, and two empiric constants, the maximum B_T (B_Tmax) and the corresponding equilibrium association bilirubin constant (K).

RESULTS

B_Tmax and K provide the variables needed to accurately estimate B_f at B_T < B_Tmax to obtain B_f at threshold B_T in patient samples. Once B_f population parameters are known, the BBP in a newborn can be used to identify poor bilirubin binding (higher B_f at the threshold B_T compared with the population) and increased risk of BIND.

CONCLUSION

The BBP can also be used in jaundice screening to better identify the actual B_T at which intervention would be prudent. The BBP is used with current B_T thresholds to better identify the risk of BIND and whether and when to intervene.

Extreme neonatal hyperbilirubinemia, acute bilirubin encephalopathy, and kernicterus spectrum disorder in children with galactosemia

BACKGROUND

Galactosemia has not been recognized as a cause of extreme neonatal hyperbilirubinemia, although growing evidence supports this association.

METHODS

In a retrospective cohort study, we identified children with galactosemia due to GALT deficiency using the Danish Metabolic Laboratory Database. Among these, we identified children with extreme neonatal hyperbilirubinemia or symptoms of ABE. Extreme neonatal hyperbilirubinemia was defined as maximum total serum bilirubin (TSB_max)) level ≥450 µmol/L and a ratio of conjugated serum bilirubin/TSB <0.30.

RESULTS

We identified 21 children with galactosemia (incidence:1:48,000). Seven children developed extreme neonatal hyperbilirubinemia (median [range] TSB_max level: 491 [456-756] µmol/L), accounting for 1.7% of all extreme neonatal hyperbilirubinemia cases. During the first 10 days of life, hyperbilirubinemia was predominantly of unconjugated type. Four children developed symptoms of intermediate/advanced ABE. One additional child had symptoms of intermediate/advanced ABE without having extreme neonatal hyperbilirubinemia. On follow-up, one child had KSD.

CONCLUSIONS

Galactosemia is a potential cause of extreme neonatal hyperbilirubinemia, ABE, and KSD. It is crucial that putative galactosemic children are treated aggressively with phototherapy to prevent ABE and KSD. Thus it is important that galactosemia is part of the work up for unconjugated hyperbilirubinemia.

The Bilirubin Binding Panel: A Henderson-Hasselbalch Approach to Neonatal Hyperbilirubinemia

Poor plasma bilirubin binding increases the risk of bilirubin neurotoxicity in newborns with hyperbilirubinemia. New laboratory tests may soon make it possible to obtain a complete bilirubin binding panel when evaluating these babies. The 3 measured components of the panel are the plasma total bilirubin concentration (B_Total), which is currently used to guide clinical care; the bilirubin binding capacity (BBC); and the concentration of non-albumin bound or free bilirubin (B_Free). The fourth component is the bilirubin-albumin equilibrium dissociation constant, K_D, which is calculated from B_Total, BBC, and B_Free The bilirubin binding panel is comparable to the panel of components used in the Henderson-Hasselbalch approach to acid-base assessment. Bilirubin binding population parameters (not prospective studies to determine whether the new bilirubin binding panel components are better predictors of bilirubin neurotoxicity than B_Total) are needed to expedite the clinical use of bilirubin binding. At any B_Total, the B_Free and the relative risk of bilirubin neurotoxicity increase as the K_D/BBC ratio increases (ie, bilirubin binding worsens). Comparing the K_D/BBC ratio of newborns with B_Total of concern with that typical for the population helps determine whether the risk of bilirubin neurotoxicity varies significantly from the inherent risk at that B_Total Furthermore, the bilirubin binding panel individualizes care because it helps to determine how aggressive intervention should be at any B_Total, irrespective of whether it is above or below established B_Total guidelines. The bilirubin binding panel may reduce anxiety, costs, unnecessary treatment, and the likelihood of undetected bilirubin neurotoxicity.

A Randomized Trial of Phototherapy with Filtered Sunlight in African Neonates

BACKGROUND

Sequelae of severe neonatal hyperbilirubinemia constitute a substantial disease burden in areas where effective conventional phototherapy is unavailable. We previously found that the use of filtered sunlight for the purpose of phototherapy is a safe and efficacious method for reducing total bilirubin. However, its relative safety and efficacy as compared with conventional phototherapy are unknown.

METHODS

We conducted a randomized, controlled noninferiority trial in which filtered sunlight was compared with conventional phototherapy for the treatment of hyperbilirubinemia in term and late-preterm neonates in a large, urban Nigerian maternity hospital. The primary end point was efficacy, which was defined as a rate of increase in total serum bilirubin of less than 0.2 mg per deciliter per hour for infants up to 72 hours of age or a decrease in total serum bilirubin for infants older than 72 hours of age who received at least 5 hours of phototherapy; we prespecified a noninferiority margin of 10% for the difference in efficacy rates between groups. The need for an exchange transfusion was a secondary end point. We also assessed safety, which was defined as the absence of the need to withdraw therapy because of hyperthermia, hypothermia, dehydration, or sunburn.

RESULTS

We enrolled 447 infants and randomly assigned 224 to filtered sunlight and 223 to conventional phototherapy. Filtered sunlight was efficacious on 93% of treatment days that could be evaluated, as compared with 90% for conventional phototherapy, and had a higher mean level of irradiance (40 vs. 17 μW per square centimeter per nanometer, P<0.001). Temperatures higher than 38.0°C occurred in 5% of the infants receiving filtered sunlight and in 1% of those receiving conventional phototherapy (P<0.001), but no infant met the criteria for withdrawal from the study for reasons of safety or required an exchange transfusion.

CONCLUSIONS

Filtered sunlight was noninferior to conventional phototherapy for the treatment of neonatal hyperbilirubinemia and did not result in any study withdrawals for reasons of safety. (Funded by the Thrasher Research Fund, Salt Lake City, and the National Center for Advancing Translational Sciences of the National Institutes of Health; Clinical Trials.gov number, NCT01434810.).

Outcome of exchange blood transfusions done for neonatal jaundice in abakaliki, South eastern Nigeria

Background:

Neonatal jaundice (NNJ) is a major cause of morbidity and mortality among neonates in Nigeria and exchange blood transfusion (EBT) is a common modality of its treatment in Ebonyi State University Teaching Hospital (EBSUTH), Abakaliki. This communication aims to audit this service.

Materials and Methods:

A 3-year retrospective review of the case files of all neonates that had EBT for NNJ at the new born special care unit of EBSUTH.

Result:

Two hundred and thirty seven (17.25%) out of 1374 neonatal admissions had NNJ. EBT was performed for 40 (16.9%) of them. The commonest indications for EBT were low birth weight/prematurity, ABO blood group incompatibility, sepsis and glucose 6 phosphate deficiencies. The mean serum bilirubin at which EBT was done was 28.3 mg/dl. The EBT was uneventful in 36 cases while in four (10%) cases there were reported adverse events. Seven neonates (17.5%) died after the procedure and documented causes of death include bilirubin encephalopathy, respiratory failure, and septic shock and disseminated intravascular coagulopathy.

Conclusion:

There is high rate of EBT use in the management of severe neonatal hyperbilirubinemia with significant morbidity and mortality in this study site. There is need to review the contribution of factors such as late presentation in the hospital to this and proffer solutions to it.

Fundamentals of phototherapy for neonatal jaundice

Phototherapy is the use of visible light for the treatment of hyperbilirubinemia in the newborn. This relatively common therapy lowers the serum bilirubin level by transforming bilirubin into water-soluble isomers that can be eliminated without conjugation in the liver. The dose of phototherapy is a key factor in how quickly it works; dose in turn is determined by the wavelength of the light, the intensity of the light (irradiance), the distance between the light and the baby, and the body surface area exposed to the light. Commercially available phototherapy systems include those that deliver light via fluorescent bulbs, halogen quartz lamps, light-emitting diodes, and fiberoptic mattresses. Proper nursing care enhances the effectiveness of phototherapy and minimizes complications. Caregiver responsibilities include ensuring effective irradiance delivery, maximizing skin exposure, providing eye protection and eye care, careful attention to thermoregulation, maintaining adequate hydration, promoting elimination, and supporting parent-infant interaction.

Prevention of neurodevelopmental sequelae of jaundice in the newborn

Although its cause, jaundice in the newborn, is extremely common, the disabling neurological disorder kernicterus is very rare. Kernicterus may be prevented by selecting those infants who are at risk of extreme jaundice or who may be particularly vulnerable to bilirubin neurotoxicity. Because the tools for achieving that goal are inadequate, a secondary strategy is needed. This involves a plan for emergency treatment of severely jaundiced infants, in particular those who present with neurological symptoms. In this paper I review the strategies for preventing extreme jaundice, and for reversing neurotoxicity in those infants for whom the principal strategies fail. Briefly, the tools for prevention include measurement of bilirubin while the infant is staying in the maternity unit, plotting the value on an hour-specific chart, assessing other risk factors for jaundice, and educating the parents. Emergency treatment should include immediate, high-irradiance phototherapy, consideration of intravenous immune globulin, and preparation for an exchange transfusion.

The role of phototherapy in the crash-cart approach to extreme neonatal jaundice

Extreme neonatal jaundice occurs infrequently but carries a high risk of permanent sequelae (kernicterus) when it does. Rapid therapeutic intervention has the potential to reduce this risk in some infants. Several case reports of infants with acute intermediate to advanced bilirubin encephalopathy shows that reversal may be possible. Phototherapy can be instituted at the flip of a switch, whereas other therapeutic measures necessarily involve delays. Therefore, high-intensity phototherapy must be regarded as an emergency measure in infants presenting with extreme jaundice and even more so in the presence of neurological symptoms. The principal and well-described effect of phototherapy involves conversion of bilirubin IXα (z, z) to more polar isomers, which are excreted in bile and urine. When care is taken to maximize the spectral power of phototherapy lights, and whenever possible with measures added to reduce the enterohepatic circulation of bilirubin, very rapid reductions in total serum bilirubin levels are possible. A hypothesis has been advanced that conversion of bilirubin to more polar photoisomers, which can reach relative concentrations of 20%-25% of total serum bilirubin within 1-2 hours, might have a direct neuroprotective effect. This theory posits that because polar molecules generally require a transporter to cross the blood-brain barrier, bilirubin photoisomers should be less prone to enter the brain. Although this theory has some support in in vitro toxicity studies, the evidence is controversial. Until further experimental support can be gained, photoconversion of bilirubin does not constitute a viable argument against instituting further measures against bilirubin neurotoxicity, such as intravenous immune globulin (when indicated) and exchange transfusion. Conversely, neither is the state of evidence an argument against immediate and effective phototherapy in the medical emergency of extreme neonatal jaundice.

High-intensity phototherapy for the treatment of severe nonhaemolytic neonatal hyperbilirubinemia

AIM

To describe the clinical approach to term and near-term newborn infants with severe hyperbilirubinaemia and to analyse the effect of high-intensity phototherapy on total serum bilirubin (TSB) levels.

METHODS

We analysed a cohort of 116 newborn infants with severe nonhaemolytic hyperbilirubinaemia (TSB ≥20 mg/dL/342 μmol/L). All patients were treated with high-intensity phototherapy. The main outcomes were reduction in TSB levels in the first 24 h of phototherapy, incidence of exchange transfusion, pathological brainstem auditory evoked responses and pathological findings on neurological examination at discharge.

RESULTS

The mean birth weight and gestational age were 3161±466 g and 37.8±1.6 weeks. Mean initial TSB concentration was 22.4±2.4 mg/dL. Per cent decreases in TSB after 2, 4, 6, 12, 18 and 24 h of phototherapy were 9.4%, 16%, 23%, 40%, 44% and 50%, respectively. No infant was treated with exchange transfusion. Brainstem evoked response audiometry (BAER) was performed in 100% of the patients, and in three of them, this examination was altered. However, when repeated 3 months later, these BAER examinations were normal. Neurological examination was normal in all patients.

CONCLUSIONS

High-intensity phototherapy significantly reduces TSB in nonhaemolytic severe hyperbilirubinaemia and decreases the need for exchange transfusion.

Phototherapy for neonatal jaundice--therapeutic effects on more than one level?

Phototherapy for jaundice is a common treatment in neonatal medicine and is used to prevent the neurotoxic effects of bilirubin. Studies have assessed the optimal wavelength of phototherapy light, the importance of irradiance and spectral power, and the types of light source, including the use of single versus multiple light sources. Outcome measures have been duration of need for phototherapy or rate of reduction of serum bilirubin over a given time. An apparent resurgence of kernicterus in recent years has forced us to focus on the emergency management of severely jaundiced infants. Several studies have shown that very rapid reductions of total serum bilirubin levels are possible. The speed with which photoisomers are formed appears to be important both from this perspective and theoretically may also be neuroprotective because of the more polar nature of the photoisomers. This work reviews the evidence concerning the speed of photoisomer formation, as well as the evidence regarding the relative neurotoxicity of bilirubin isomers.

Early isomerization of bilirubin in phototherapy of neonatal jaundice

Neonatal jaundice is usually treated with phototherapy that converts bilirubin to more polar stereoisomers. These should theoretically be less able to cross the blood-brain barrier. The rates of photoisomer formation and concentrations accumulating in the circulation may have a bearing on the risk of kernicterus. The purpose of this study was to determine the rate of appearance of the major 4Z, 15E photoisomer of bilirubin during the early stages of phototherapy. Twenty jaundiced neonates were treated with phototherapy, and blood samples were drawn before and at approximately 15, 30, 60, and 120 min (10 infants) or at approximately 15, 60, 120, and 240 min (10 infants) after beginning phototherapy. Blood samples were analyzed for total serum bilirubin (TSB) and the 4Z, 15E photoisomer of bilirubin. Significant (p<0.0001) formation of the 4Z, 15E photoisomer was detectable within 15 min. The change in TSB from time 0 was insignificant at 120 min but reached significance at 240 min (p<0.001). The 4Z, 15E bilirubin constituted up to 20-25% of TSB at 2 h and may not have peaked by 4 h. Further studies are needed to determine whether this early shift in balance between bilirubin isomers with different polarities may impact the risk of bilirubin encephalopathy even before TSB starts to fall.

Reversibility of acute intermediate phase bilirubin encephalopathy

AIM

To show the potential for reversing acute intermediate to advanced phase bilirubin encephalopathy.

METHODS

Case studies.

RESULTS

Six extremely jaundiced infants had symptoms of intermediate to advanced phase acute bilirubin encephalopathy. The infants were treated aggressively. Two patients had brain magnetic resonance imaging showing increased signals in the globus pallidus. On follow-up, all infants are neurologically normal.

CONCLUSIONS

Intermediate-to-advanced stage acute bilirubin encephalopathy may occasionally be reversible. These cases provide a strong argument in favour of rapid and aggressive intervention in infants presenting with extreme jaundice and neurological symptoms.

Why we are still doing so many exchange blood transfusion for neonatal jaundice in Nigeria

BACKGROUND

Since exchange blood transfusion (EBT) is associated with serious complications, phototherapy has been made more powerful to reduce the need for EBT in the developed world. This study was undertaken to determine the indications for EBT in neonatal jaundice (NNJ) at our unit and what proportion of EBTs was possibly avoidable.

METHODS

All the babies who had EBT for hyperbilirubinemia over a three-year period were included. Age, sex, weight, place of delivery, blood group of baby and mother, other investigations, management, and the outcome of the babies were recorded.

RESULTS

Of the 1686 babies admitted to the neonatal unit, 90 (5.3%) had EBT. Fourteen (15.6%) were inborn while 76 (84.4%) were out-born babies. Fifty-six (62.2%) babies were admitted primarily for NNJ while 34 (37.8%) developed NNJ during admission. Thirty-six (40.0%) of the babies had phototherapy for more than 24 hours prior to EBT either because they were of very low birthweight or NNJ was detected very early and therapy was so commenced. Sixty-eight (75.6%) babies had single EBT while the remaining 22 (24.4%) had two sessions of EBT. Factors associated with severe NNJ in babies requiring EBT included low birthweight (<2500 g, 44.4%), ABO incompatibility (30.0%), glucose-6-phosphate dehydrogenase deficiency (34.4%) and septicemia (26.1%). Twenty-seven (30.0%) of the neonates developed features of kernicterus: 26 before admission while 1 during admission; all except one were delivered outside the hospital.

CONCLUSIONS

The EBT rate in our center was high. With more effective phototherapy, EBT could be avoided in most of the babies who initially had phototherapy for more than 24 hours before EBT and repeated EBT sessions. Health education of the population at risk, especially pregnant women, and early referral at the primary health care level will reduce the burden of severe NNJ.

Clinical report from the pilot USA Kernicterus Registry (1992 to 2004)

To identify antecedent clinical and health services events in infants (>/=35 weeks gestational age (GA)) who were discharged as healthy from their place of birth and subsequently sustained kernicterus. We conducted a root-cause analysis of a convenience sample of 125 infants >/=35 weeks GA cared for in US healthcare facilities (including off-shore US military bases). These cases were voluntarily reported to the Pilot USA Kernicterus Registry (1992 to 2004) and met the eligibility criteria of acute bilirubin encephalopathy (ABE) and/or post-icteric sequelae. Multiple providers at multiple sites managed this cohort of infants for their newborn jaundice and progressive hyperbilirubinemia. Clinical signs of ABE, verbalized by parents, were often inadequately elicited or recorded and often not recognized as an emergency. Clinical signs of ABE were reported in 7 of 125 infants with a subsequent diagnosis of kernicterus who were not re-evaluated or treated for hyperbilirubinemia, although jaundice was noted at outpatient visits. The remaining infants (n=118) had total serum bilirubin (TSB) levels >20 mg per 100 ml (342 micromol l(-1); range: 20.7 to 59.9 mg per 100 ml). No specific TSB threshold coincided with onset of ABE. Of infants <37 weeks GA with kernicterus, 34.9% were LGA (large for gestational age) as compared with 24.7% of term infants (>37 weeks GA). Although >90% mothers initiated breast-feeding, assessment of milk transfer and lactation support was suboptimal in most. Mortality was 4% (5 of 125) in infants readmitted at age </=1 week. Along with a rapid rise of TSB (>0.2 mg per 100 ml per hour), contributing factors, alone or in combination, included undiagnosed hemolytic disease, excessive bilirubin production related to extra-vascular hemolysis and delayed bilirubin elimination (including increased enterohepatic circulation, diagnosed and undiagnosed genetic disorders) in the context of known late prematurity (<37 weeks), glucose 6-phosphate-dehydrogenase deficiency, infection and dehydration. Readmission was at age </=5 days in 81 of 118 (69%) infants and <10 days in 101 of 118 (86%) infants. TSB levels were </=35 mg per 100 ml (598 micromol l(-1)) in 46 (39%) infants, of whom one died before exchange transfusion, one was untreated and one was lost to follow-up. Timely and efficacious bilirubin reduction interventions defined by 'crash-cart' initiation of immediate intensive phototherapy and urgent exchange transfusion were accomplished in 11 of 43 infants, which were compared with 12 of 43 infants in whom a timely exchange sometimes could not be accomplished. No overt sequelae were found in 8 of 11 infants (73%) treated with a 'crash-cart' approach compared with none without sequelae when exchange was delayed by pre-admission delays, technical factors or need to transfer to a tertiary facility. None of the remaining 20 of 43 infants treated only with phototherapy escaped sequelae. Regardless of age at readmission and intervention, infants with peak measured TSB >35 mg per 100 ml had post-icteric sequelae (n=73). There was a narrow margin of safety between birthing hospital discharge or home birth and readmission to a tertiary neonatal/pediatric facility. Progression of hyperbilirubinemia to hazardous levels and onset of neurological signs were often not identified as infant's care and medical supervision transitioned during the first week after birth. The major underlying root cause for kernicterus was systems failure of services by multiple providers at multiple sites and inability to identify the at-risk infant and manage severe hyperbilirubinemia in a timely manner.

Fundamentals of phototherapy for neonatal jaundice

Phototherapy is the use of visible light for the treatment of hyperbilirubinemia in the newborn. This relatively common therapy lowers the serum bilirubin level by transforming bilirubin into water-soluble isomers that can be eliminated without conjugation in the liver. The dose of phototherapy largely determines how quickly it works; the dose, in turn, is determined by the wavelength of the light, the intensity of the light (irradiance), the distance between the light and the infant, and the body surface area exposed to the light. Commercially available phototherapy systems include those that deliver light via fluorescent bulbs, halogen quartz lamps, light-emitting diodes, and fiberoptic mattresses. Proper nursing care enhances the effectiveness of phototherapy and minimizes complications. Caregiver responsibilities include ensuring effective irradiance delivery, maximizing skin exposure, providing eye protection and eye care, carefully monitoring thermoregulation, maintaining adequate hydration, promoting elimination, and supporting parent-infant interaction.

Early recognition of neonatal hyperbilirubinemia and its emergent management

Hyperbilirubinemia and kernicterus are re-emerging as prominent clinical concerns and have been hypothesized to be secondary to increased breast-feeding rates, early hospital discharges and overall lack of concern for the potential impact of severe hyperbilirubinemia on healthy term newborns. Although the clinical symptoms can be non-specific and vague, they could be early, insidious and heralding signs of acute bilirubin encephalopathy (ABE) or acute stage kernicterus. Because it is highly prevalent, evaluation of a jaundiced neonate requires detailed questions about specific signs, review of birth and postnatal histories, evaluation of predischarge data, and possibly an emergency clinical evaluation of the neurological status of the infant. Medical urgency to evaluate, investigate and monitor such a newborn ensues from the possibility of rapid progression that might lead to permanent sequelae of bilirubin-induced neurologic dysfunction (BIND). Early recognition of the urgency and rapid transition to treatment seem to be the major barriers leading to delay in therapy. However, because there is a well-established and relatively safe treatment for neonatal jaundice, there should be zero tolerance for kernicterus, and BIND prevention has become a national priority in the USA. This paper reviews the clinical signs and epidemiology of ABE and BIND and presents a system-based strategy for preventing their occurrence, focusing particularly on the transition from recognition of clinical jaundice to actual treatment. A novel emergency-room-based protocol is presented as an example of how to expedite and facilitate rapid progression to treatment.

A randomized controlled trial of fluid supplementation in term neonates with severe hyperbilirubinemia

OBJECTIVE

To evaluate the effectiveness of fluid supplementation in decreasing the rate of exchange transfusion and the duration of phototherapy in term neonates with severe nonhemolytic hyperbilirubinemia.

STUDY DESIGN

This was a randomized controlled trial conducted in a tertiary care referral unit in northern India. Seventy-four term neonates with severe nonhemolytic hyperbilirubinemia (total serum bilirubin > 18 mg/dL [308 micromol/L] to < 25 mg/dL [427 micromol/L]). The subjects were randomized to an "extra fluids" group (intravenous fluid supplementation for 8 hours and oral supplementation for the duration of phototherapy; n = 37) or a control group (n = 37).

RESULTS

At inclusion, 54 infants (73%) had high serum osmolality, including 28 (75%) in the extra fluids group and 26 (70%) in the control group. The proportion of infants who underwent exchange transfusion was lower in the extra fluids group than in the control group: 6 (16%) versus 20 (54%)(P = .001; relative risk = 0.30; 95% confidence interval = 0.14 to 0.66). The duration of phototherapy was also shorter in the extra fluids group: 52 +/- 18 hours versus 73 +/- 31 hours (P = .004).

CONCLUSION

Fluid supplementation in term neonates presenting with severe hyperbilirubinemia decreased the rate of exchange transfusion and duration of phototherapy.

Recent advances in the pharmacotherapy for hyperbilirubinaemia in the neonate

Jaundice is a common cause for diagnostic works-up and therapeutic intervention in neonates. This is motivated by the risk for severe neurological sequelae (kernicterus). The mainstays of treatment for the past decades have been exchange transfusion and phototherapy. Exchange transfusion is now becoming rare due to immune prophylaxis in Rhesus-negative women, and treatment of sensitised infants with intravenous immunoglobulin. Several different pharmacological approaches have been studied as far as the treatment of neonatal jaundice. Of these, the focus of attention in recent years has been on the haem oxygenase inhibitors (metal meso- and protoporphyrins). These are effective inhibitors of bilirubin production and have been shown to significantly reduce peak serum bilirubin levels in several clinical trials, both when used prophylactically and therapeutically. However, questions remain regarding long-term safety, as well as the advisability of whole-scale inhibition of bilirubin production. Nevertheless, in selected infants with a high risk of severe jaundice, the use of haem oxygenase inhibitors may be acceptable. Pharmacotherapy in jaundiced infants is fraught with risks, as many drugs may increase the entry of bilirubin into the brain and presumably, the risk for neurotoxicity. Both the displacement of bilirubin from its albumin binding and interference with the function of phosphoglycoprotein in the blood-brain barrier are documented mechanisms in this respect.

In vitro and in vivo efficacy of new blue light emitting diode phototherapy compared to conventional halogen quartz phototherapy for neonatal jaundice

High intensity light emitting diodes (LEDs) are being studied as possible light sources for the phototherapy of neonatal jaundice, as they can emit high intensity light of narrow wavelength band in the blue region of the visible light spectrum corresponding to the spectrum of maximal bilirubin absorption. We developed a prototype blue gallium nitride LED phototherapy unit with high intensity, and compared its efficacy to commercially used halogen quartz phototherapy device by measuring both in vitro and in vivo bilirubin photodegradation. The prototype device with two focused arrays, each with 500 blue LEDs, generated greater irradiance than the conventional device tested. The LED device showed a significantly higher efficacy of bilirubin photodegradation than the conventional phototherapy in both in vitro experiment using microhematocrit tubes (44+/-7% vs. 35+/-2%) and in vivo experiment using Gunn rats (30+/-9% vs. 16+/-8%). We conclude that high intensity blue LED device was much more effective than conventional phototherapy of both in vitro and in vivo bilirubin photodegradation. Further studies will be necessary to prove its clinical efficacy.

Phototherapy: current methods and future directions

Phototherapy is the most common therapeutic intervention used for the treatment of hyperbilirubinemia. Although it has become a mainstay since its introduction in 1958, a better understanding of the photobiology of bilirubin, characteristics of the phototherapy devices, the efficacy and safety considerations of phototherapy applications, and improvements in spectroradiometers and phototherapy devices are necessary for more predictable and improved clinical practices and outcomes. A step forward in instituting consistent, uniform, and effective use of phototherapy is the recent American Academy of Pediatrics clinical guideline on the management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation, which outlines a clinical strategy for the diagnosis of hyperbilirubinemia and contains direct recommendations for the application of phototherapy. This article reviews the parameters that determine the efficacy of phototherapy, briefly discusses current devices and methods used to deliver phototherapy, and speculates on future directions and studies that are still needed to complement our presently incomplete knowledge of the facets of this common mode of therapy.

Management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation

Jaundice occurs in most newborn infants. Most jaundice is benign, but because of the potential toxicity of bilirubin, newborn infants must be monitored to identify those who might develop severe hyperbilirubinemia and, in rare cases, acute bilirubin encephalopathy or kernicterus. The focus of this guideline is to reduce the incidence of severe hyperbilirubinemia and bilirubin encephalopathy while minimizing the risks of unintended harm such as maternal anxiety, decreased breastfeeding, and unnecessary costs or treatment. Although kernicterus should almost always be preventable, cases continue to occur. These guidelines provide a framework for the prevention and management of hyperbilirubinemia in newborn infants of 35 or more weeks of gestation. In every infant, we recommend that clinicians 1) promote and support successful breastfeeding; 2) perform a systematic assessment before discharge for the risk of severe hyperbilirubinemia; 3) provide early and focused follow-up based on the risk assessment; and 4) when indicated, treat newborns with phototherapy or exchange transfusion to prevent the development of severe hyperbilirubinemia and, possibly, bilirubin encephalopathy (kernicterus).

Effects of phototherapy in neonates on circadian sleep-wake and saliva cortisol level rhythms

The influence of phototherapy treatment during the neonatal period on sleep-wake rhythm, and its long-term effects on biological rhythms, was evaluated in preterm and full-term infants. Forty-three infants treated with phototherapy during the neonatal period and 47 untreated infants were examined for entrainment of sleep-wake rhythms between 16 and 52 weeks and for sleep-wake and saliva cortisol rhythms at 2.5 years of age. The age of sleep-wake rhythm entrainment was not significantly different between the 2 groups. No correlations between duration of exposure to phototherapy and corrected age of entrainment of sleep-wake rhythm were observed. At follow-up, no significant differences in sleep-wake and saliva cortisol rhythms were observed between the 2 groups, indicating that circadian variations were similar to those in adults.

Infants with bilirubin levels of 30 mg/dL or more in a large managed care organization

OBJECTIVE

To describe the incidence, etiology, treatment, and outcome of newborns with total serum bilirubin (TSB) levels >or=30 mg/dL (513 micro mol/L).

DESIGN

Population-based case series.

SETTING

Eleven Northern California Kaiser Permanente Medical Care Program hospitals and 1 affiliated hospital.

PATIENTS

Eleven infants with TSB levels of >or=30 mg/dL in the first 30 days after birth, identified using computer databases from a cohort of 111,009 infants born 1995-1998.

OUTCOME MEASURES

Clinical data from the birth hospitalization, rehospitalization, and outpatient visits in all infants; psychometric testing at age 5 (N = 3), neurologic examinations by child neurologists at age 5 (N = 3), or primary care providers (N = 7; mean age: 2.2 years); Parent Evaluation of Developmental Status (N = 8; mean age: 4.2 years).

RESULTS

Maximum TSB levels of the 11 infants ranged from 30.7 to 45.5 mg/dL (525 micro mol/L to 778 micro mol/L; mean: 34.9 mg/dL [597 micro mol/L]). Four were born at 35 to 36 weeks gestation, and 7 were exclusively breastfed. Two had apparent isoimmunization; the etiology for the other 9 remained obscure, although only 4 were tested for glucose-6-phosphate dehydrogenase deficiency and 1 was bacteremic. None had acute neurologic symptoms. All received phototherapy and 5 received exchange transfusions. One infant died of sudden infant death syndrome; there was no kernicterus at autopsy. Two were lost to follow-up but were neurologically normal when last seen for checkups at 18 and 43 months. One child was receiving speech therapy at age 3. There were no significant parental concerns or abnormalities in the other children.

CONCLUSIONS

In this setting, TSB levels >or=30 mg/dL were rare and generally unaccompanied by acute symptoms. Although we did not observe serious neurodevelopmental sequelae in this small sample, additional studies are required to quantify the known, significant risk of kernicterus in infants with very high TSB levels.

Effect of acidosis on bilirubin-induced toxicity to human erythrocytes

Unconjugated bilirubin binds to erythrocytes, eliciting crenation, lipid elution and hemolysis. The present work attempts to establish the role of acidosis on bilirubin-induced toxicity to human erythrocytes. To this end, pH values ranging from 7.0-8.0 were used to induce a different representation of acid and anionic bilirubin species, respectively. Erythrocytes from healthy donors were incubated with bilirubin and albumin (3:1, molar ratio), during 4 h. Erythrocyte-bound bilirubin was evaluated by albumin or chloroform extraction in an attempt to assess either mono- and dianion bilirubin adsorbed on the cell surface or colloidal aggregates, respectively. Cytotoxicity indicators, such as the morphological index, and the extent of phospholipids and hemoglobin release were also determined. The results showed that as pH drops from 8.0-7.0, less bilirubin is removed by albumin and more become recovered by chloroform. The data corroborate the predominance of anionic and non-aggregated bilirubin species at pH 8.0 with dimers and precipitates occurring at 7.0. In accordance, crenation and cell lysis were four times increased at acidic pH. In contrast, elution of phospholipids was 1.5 times less evident at the same pH, thus suggesting that formation of bilirubin complexes with membrane phospholipids may have contributed to prevent their release. In conclusion, both anionic and acid bilirubin species interact with human erythrocytes leading to cytotoxic alterations that may determine definitive lesions. Nevertheless, increased vulnerability to crenation and hemolysis are more likely to occur in acidic conditions pointing to the bilirubin precipitates as the main candidates of bilirubin-induced toxicity to erythrocytes.

Mechanisms of bilirubin toxicity: clinical implications

The basic mechanism of kernicterus and bilirubin encephalopathy has not been unequivocally determined. Much knowledge has been gained about phenomena that contribute to bilirubin neurotoxicity, and this knowledge has implications for clinical practice. Conditions that impact on blood-brain barrier function, increase brain blood flow, or impact on bilirubin metabolism, including its transport in serum, should be avoided, if possible. Such conditions include drugs and drug stabilizers that compete with bilirubin binding to albumin, or that inhibit P-glycoprotein in the blood-brain barrier, prematurity/immaturity, and clinically significant illness in the infant that involves hemolysis, respiratory and metabolic acidosis, infection, asphyxia, hypoxia and (perhaps) hyperoxia, and hyperosmolality. If these conditions are not avoidable then there should be a more aggressive approach to the treatment of hyperbilirubinemia. The limits of tolerance for hyperbilirubinemia varies among neonates and there are no tools to determine with certainty when a particular infant is approaching the danger zone. Neurological symptoms in a jaundiced infant require extreme vigilance, and, in most cases, immediate intervention.

Kernicterus: an international perspective

Kernicterus occurs in all parts of the world. The risk is increased in countries where glucose-6-phosphate dehydrogenase-deficiency is common. In the 1990's more case reports of infants who developed kernicterus were published than in the previous decades. A combination of reduced concern for jaundice in newborns, early discharge with inadequate follow-up and a decreased awareness of the signs that may herald serious toxicity may have contributed to the apparent increase in the incidence of kernicterus. Although most jaundiced newborns do not need aggressive evaluation or treatment, physicians who deal with such infants still need to be vigilant. We lack the necessary tools to distinguish infants who may be particularly vulnerable to the effects of bilirubin on the brain from those who may tolerate high serum bilirubin levels without harm. Therefore it is imperative that each infant with significant jaundice be conscientiously evaluated and a plan for testing and, if necessary, therapy be formulated. Transcutaneous measurement of bilirubin is a simple tool that significantly reduces the need for invasive tests. Signs of possible neurotoxicity must never be disregarded or neglected. Any jaundiced infant who shows signs of possible neurotoxicity should receive intensive phototherapy as an emergency procedure while further evaluation continues. Further studies regarding bilirubin toxicity and neonatal jaundice are needed, both in the basic science as well as in the clinical arena.

Phototherapy--traditional and nontraditional

An observation by an English nurse in 1956 led to the discovery that visible light could lower serum bilirubin levels in newborn infants, and subsequent research showed how photons of light energy are absorbed by the bilirubin molecule converting it into isomers that are readily excreted by the liver and the kidney. Understanding the dose-response effect and other factors that influence the way light works to lower bilirubin levels has led to the effective use of phototherapy and has eliminated the need for exchange transfusion in almost all jaundiced infants.

Assessment of bilirubin toxicity to erythrocytes. Implication in neonatal jaundice management

BACKGROUND

Neonatal hyperbilirubinaemia remains one of the most common clinical conditions requiring therapeutic intervention. Nevertheless, reliable indicators of bilirubin toxicity are still missing. This prompted us to investigate (a) the progression of cytotoxic events produced by increasing concentrations of bilirubin; (b) the relevance of the membrane lipid package on bilirubin binding to erythrocytes; and (c) the reliability of chloroform extraction compared with albumin extraction to evaluate erythrocyte-bound bilirubin and cytotoxicity.

MATERIALS AND METHODS

Morphological alterations, free bilirubin, erythrocyte-bound bilirubin (albumin- and chloroform-extractable), haemolysis and membrane-released lipids, were determined in human erythrocytes at 4 degrees C or 37 degrees C, after 4 h incubation at pH 7.4, with increasing molar ratios of bilirubin to albumin (0.5-5). The reversibility of cytotoxicity by albumin washing was assessed by morphological analysis.

RESULTS

Decreased free bilirubin, lower erythrocyte-bound bilirubin concentration by albumin extraction (superficial/non-aggregated bilirubin) and higher values by chloroform extraction (deep/aggregated bilirubin) were observed for 37 degrees C vs. 4 degrees C, at molar ratios > 1. Echinocytosis increased with bilirubin concentration and temperature and was not fully reversed by albumin washing. Haemolysis was already significant at a molar ratio of 1, and was enhanced by temperature at molar ratios 3 and 5 (P < 0.01). The loss of membrane lipids was remarkable at molar ratios > or = 0.5, both at 4 degrees C and 37 degrees C (P < 0.01), although correlation with bilirubin concentration was only significant at 37 degrees C (r = 0.971; P < 0.01).

CONCLUSIONS

These results suggest that increased lipid fluidity and high bilirubin concentrations promote membrane bilirubin translocation and toxicity. They also show that albumin is not able to displace the bilirubin located deeply or aggregated within the membrane, which in turn is removed by chloroform. Accordingly, chloroform-extractable rather than albumin-extractable bilirubin is a more accurate parameter to assess erythrocyte-bound bilirubin during severe hyperbilirubinaemia.

[Management of hyperbilirubinemia of the term newborn in maternity wards]

Jaundice is a frequent clinical sign among healthy term newborns. A rigorous clinical assessment is crucial in order to recognise haemolytic, infectious and metabolic diseases. The use of the transcutaneous jaundice-meter in decision-making, and the phototherapy principles and applications, are discussed. Intensive phototherapy allows a rapid decrease in plasma bilirubin levels, so that it may used to treat even severe hyperbilirubinemia in the maternity ward.