Kernicterus in late preterm infants cared for as term healthy infants

Transcutaneous bilirubin levels in late preterm neonates

OBJECTIVE

To examine transcutaneous bilirubin (TcB) levels in late preterm neonates.

STUDY DESIGN

Between July 2006 and December 2009, we performed 4387 TcB measurements with a BiliCheck bilirubinometer in 793 healthy late preterm neonates at designated times up to 120 postnatal hours. TcB percentiles are presented on an hour-specific nomogram. Mean increment TcB rates and the rates of increase for different percentiles are calculated as well.

RESULTS

We present a percentile-based nomogram that reflects the natural history of TcB in late preterm neonates up to the fifth day of life. TcB levels demonstrated a different pattern of increase in neonates who developed significant hyperbilirubinemia compared with those who did not. However, the rates of TcB increase were quite similar up to age 48 hours, with a substantial overlap of TcB values between the two groups.

CONCLUSIONS

We developed of a TcB nomogram designated for hour-specific evaluation of hyperbilirubinemia in neonates born between 35(0/7) and 37(6/7) weeks' gestation.

Auditory neuropathy spectrum disorder in late preterm and term infants with severe jaundice

OBJECTIVE

To evaluate if severe jaundice is associated with acute auditory neuropathy spectrum disorder in otherwise healthy late preterm and term neonates.

METHODS

In a prospective observational study, all neonates who were admitted with severe jaundice at which exchange transfusion may be indicated as per American Academy of Pediatrics guidelines had comprehensive auditory evaluation performed before discharge to home. Neonates with infection, perinatal asphyxia, chromosomal disorders, cranio-facial malformations, or family history of childhood hearing loss were excluded. Comprehensive auditory evaluations (tympanometry, oto-acoustic emission tests, and auditory brainstem evoked responses) were performed by an audiologist unaware of the severity of jaundice. Total serum bilirubin and serum albumin were measured at the institutional chemistry laboratory using the Diazo and Bromocresol purple method, respectively.

RESULTS

A total of 13 neonates with total serum bilirubin concentration at which exchange transfusion is indicated as per American Academy of Pediatrics were admitted to the Neonatal Intensive Care Unit over 3 month period. Six out of 13 neonates (46%) had audiological findings of acute auditory neuropathy spectrum disorder. There was no significant difference in gestational age, birth weight, hemolysis, serum albumin concentration, peak total serum bilirubin concentrations, and peak bilirubin:albumin molar ratio between six neonates who developed acute auditory neuropathy and seven neonates who had normal audiological findings. Only two out of six infants with auditory neuropathy spectrum disorder had clinical signs and symptoms of acute bilirubin encephalopathy.

CONCLUSIONS

Our findings strongly suggest that auditory neuropathy spectrum disorder is a common manifestation of acute bilirubin-induced neurotoxicity in late preterm and term infants with severe jaundice. Our findings also suggest that comprehensive auditory evaluations should be routinely performed in neonates with severe jaundice irrespective of the presence of clinical findings of acute bilirubin encephalopathy.

Universal bilirubin screening for severe neonatal hyperbilirubinemia

To reduce the incidence of severe neonatal hyperbilirubinemia affecting newborns with jaundice in the United States and to prevent kernicterus, there is a need to implement proven prevention strategies for severe neonatal hyperbilirubinemia as recommended in the 2004 American Academy of Pediatrics Guidelines for newborns >35 weeks gestational age. The purpose of universal predischarge bilirubin screening is to identify infants with bilirubin levels >75th percentile for age in hours and track those with rapid rates of bilirubin rise (>0.2 mg per 100 ml per h). Early identification has been reported to predict severe hyperbilirubinemia and allow for evidence-based targeted interventions. A systems approach is likely to reduce the preventable causes of acute bilirubin encephalopathy. To do so, highest priority should be given to (i) designating extreme hyperbilirubinemia (total serum bilirubin >427 μmol l(-1) or >25 mg per 100 ml) as a reportable condition by laboratories and health-care providers through public health mandates; (ii) implementation of Joint Commission's Sentinel Report for kernicterus; (iii) nursing outreach to communities for education of prospective parents; (iv) development of clinical pathways to monitor, evaluate and track infants with extreme hyperbilirubinemia; and (v) societal awareness. These efforts should be monitored by a state and national surveillance system in order to critically improve the timeliness and completeness of notifications and to allow evaluation and interventions at the policy and individual family level.

Determinants of morbidity in late preterm infants

OBJECTIVE

To assess the effect of selected maternal medical conditions and complications of pregnancy on the risk for morbidity among late preterm neonates.

DESIGN

Prospective cohort study.

MATERIAL AND METHODS

A total of 548 late preterm neonates (34(0/7) to 36(6/7)weeks' gestation) delivered from August 2006 to July 2009, were included. Information regarding demographics, gestational age, mode of delivery, maternal age and parity, pre-existing medical conditions and complications of pregnancy were obtained and associated with neonatal morbidity, both independently and as joint exposures. Newborn morbidity was defined by combining specific diagnoses, length of hospital stay, and transfer to the Neonatal Intensive Care Unit.

RESULTS

Overall, 165 (30.1%) of the late preterm infants suffered from morbidity. The morbidity rates were 16.8% at 36 weeks' gestation, and then approximately doubled from 38.2% at 35 weeks to 59.7% at 34 weeks. The joint effect of gestational age (OR 8.43 for 34 weeks and 3.60 for 35 weeks' gestation), small for gestational age (SGA) (OR 4.18), multiple gestation (OR 3.68) and lack of antenatal steroid administration (OR 4.03), was greater than the independent effect of each of these factors, and greater than additive. Emergency caesarean section (OR 1.43) and antepartum haemorrhage (OR 3.07) were also associated with a significant impact on neonatal morbidity.

CONCLUSIONS

The risk for morbidity among late preterm infants, changes with each passing week of gestation. This risk seems to be intensified, when other exposures such as SGA, multiple gestation, emergency caesarean section, lack of antenatal steroid administration and antepartum haemorrhage, are also present.

Late preterm infants: birth outcomes and health care utilization in the first year

OBJECTIVE

To distinguish the effects of late preterm birth from the complications associated with the causes of delivery timing, this study used propensity score-matching methods on a statewide database that contains information on both mothers and infants.

METHODS

Data for this study came from Arkansas Medicaid claims data linked to state birth certificate data for the years 2001 through 2005. We excluded all multiple births, infants with birth defects, and infants at <33 weeks of gestation. Late preterm infants (LPIs) (34 to 36 weeks of gestation) were matched with term infants (37-42 weeks of gestation) according to propensity scores, on the basis of infant, maternal, and clinical characteristics.

RESULTS

A total of 5188 LPIs were matched successfully with 15303 term infants. LPIs had increased odds of poor outcomes during their birth hospitalization, including a need for mechanical ventilation (adjusted odds ratio [aOR]: 1.31 [95% confidence interval [CI]: 1.01-1.68]), respiratory distress syndrome (aOR: 2.84 [95% CI: 2.33-3.45]), and hypoglycemia (aOR: 1.60 [95% CI: 1.26-2.03]). Outpatient and inpatient Medicaid expenditures in the first year were both modestly higher (outpatient, adjusted marginal effect: $108 [95% CI: $58-$158]; inpatient, $597 [95% CI: $528-$666]) for LPIs.

CONCLUSIONS

LPIs are at increased risk of poor health-related outcomes during their birth hospitalization and of increased health care utilization during their first year.

Hyperbilirubinemia in African American neonates: clinical issues and current challenges

African American neonates evidence a low incidence of hyperbilirubinemia yet account for more than 25% of the reported kernicterus cases in the USA. Glucose-6-phosphate dehydrogenase (G6PD) deficiency accounts for approximately 60%, and late preterm gestation and ABO hemolytic disease approximately 40% of these cases. Females heterozygous for G6PD A- harbor a population of G6PD-deficient red blood cells and are at risk for hyperbilirubinemia. Pre-discharge bilirubin measurement coupled with gestational age enhances the identification of neonates at hyperbilirubinemia risk. Parental education at the time of birth hospitalization discharge combined with timely follow-up may help to reduce the risk of developing hazardous hyperbilirubinemia.

Neonatal outcomes of late-preterm birth associated or not with intrauterine growth restriction

Objective. To compare neonatal morbidity and mortality between late-preterm intrauterine growth-restricted (IUGR) and appropriate-for-gestational-age (AGA) infants of the comparable gestational ages (GAs). Methods. We retrospectively analyzed neonatal morbidity and mortality of 50 singleton pregnancies involving fetuses with IUGR delivered between 34 and 36 6/7 weeks of GA due to maternal and/or fetal indication. The control group consisted of 36 singleton pregnancies with spontaneous preterm delivery at the same GA, in which the infant was AGA. Categorical data were compared between IUGR and AGA pregnancies by X² analysis and Fisher's exact test. Ordinal measures were compared using the Kruskal-Wallis test. Results. The length of stay of newborns in the nursery, as well as the need for and duration of hospitalization in the neonatal intensive care unit, was longer in the group with IUGR. Transient tachypnea of the newborn or apnea rates did not differ significantly between the IUGR and AGA groups. IUGR infants were found to be at a higher risk of intraventricular hemorrhage. No respiratory distress syndrome, pulmonary hemorrhage or bronchopulmonary dysplasia was observed in either group. The frequency of sepsis, thrombocytopenia and hyperbilirubinemia was similar in the two groups. Hypoglycemia was more frequent in the IUGR group. No neonatal death was observed. Conclusion. Our study showed that late-preterm IUGR infants present a significantly higher risk of neonatal complications when compared to late-preterm AGA infants.

Timing of elective repeat caesarean section: maternal and neonatal morbidity and mortality

Timing of elective repeat caesarean section should take into account both fetal and maternal considerations. The percentage of caesarean deliveries has dramatically increased during the last decades. It undoubtedly leads to an increase in the number of women having multiple caesarean sections. While maternal morbidity increases with increased number of caesarean sections, when compared with their term counterparts, late pre-term infants face increased morbidity. Establishing the optimal time of delivery for both mother and child is a major challenge faced by clinicians. The aim of this review is to better understand neonatal and maternal morbidity and mortality that are associated with elective repeat caesarean section, and to provide an educated decision regarding the optimal timing for elective repeat caesarean section.

Role of the pediatric nurse practitioner in promoting breastfeeding for late preterm infants in primary care settings

The preterm birth rate has been increasing steadily during the past two decades. Up to two thirds of this increase has been attributed to the increasing rate of late preterm births (34 to < 37 gestational weeks). The advantages of breastfeeding for premature infants appear to be even greater than for term infants; however, establishing breastfeeding in late-preterm infants is frequently more problematic. Because of their immaturity, late preterm infants may have less stamina; difficulty with latch, suck, and swallow; temperature instability; increased vulnerability to infection; hyperbilirubinemia, and more respiratory problems than the full-term infant. Late preterm infants usually are treated as full term and discharged within 48 hours of birth, so pediatric nurse practitioners in primary care settings play a critical role in promoting breastfeeding through early assessment and detection of breastfeeding difficulties and by providing anticipatory guidance related to breastfeeding and follow-up. The purpose of this article is to describe the developmental and physiologic immaturity of late preterm infants and to highlight the role of pediatric nurse practitioners in primary care settings in supporting and promoting breastfeeding for late preterm infants.

Clinical characteristics of G6PD deficiency in infants with marked hyperbilirubinemia

This study analyzes the clinical features of glucose-6-phosphate dehydrogenase (G6PD) deficiency in infants with marked hyperbilirubinemia. We retrospectively assessed a cohort of 413 infants with peak total serum bilirubin (TSB) level >or=20 mg/dL from 1995 to 2007. The prevalence of G6PD deficiency was proportional to the level of peak TSB: 21.1% (81/383) in 20 mg/dL to 29.9 mg/dL, 45.5% (10/22) in 30 mg/dL to 39.9 mg/dL, and 100% (8/8) in >or=40 mg/dL. Male sex was more common in G6PD deficiency (75.8%). When compared with G6PD-normal infants, those with G6PD deficiency tended to have extreme hyperbilirubinemia (peak TSB level >or=25 mg/dL) and hemoglobin value<13 g/dL (P<0.001). Furthermore, mortality rate was significantly higher in G6PD-deficient infants (3.0%) than in the G6PD-normal counterparts (0.0%). Among 58 of the G6PD-deficient infants who were followed for more than 12 months, 4 developed the classic neurologic manifestations of kernicterus (6.6%). These findings show that G6PD deficiency is an important risk factor of extreme hyperbilirubinemia, death, and kernicterus.

Late preterm birth: how often is it avoidable?

OBJECTIVE

Our objective was to describe indications for late preterm birth (LPTB) and estimate the frequency of potentially avoidable LPTB deliveries.

STUDY DESIGN

Singleton pregnancies delivered between 34(0/7)-36(6/7) weeks over a 1-year period at a tertiary care medical center were studied. Indications for delivery were categorized as spontaneous (spontaneous preterm birth or premature rupture of membranes) or iatrogenic (elective or medically indicated). Potentially avoidable deliveries were defined as those with elective or medical stable, but high-risk indications.

RESULTS

During the study period there were 514 LPTB (spontaneous preterm birth 36.2%, preterm premature rupture of membranes 17.7%, medically indicated 37.9%, and elective 8.2%). Potentially avoidable LPTB accounted for 17% of LPTB and were associated with later gestational age (odds ratio [OR], 4.7; 95% confidence interval [CI], 2.5-8.6), nonfaculty physician status (OR, 2.8; 95% CI, 1.5-5.1), and prior cesarean delivery (OR, 1.5; 95% CI, 1.0-2.1).

CONCLUSION

At our institution, <10% of LPTB are purely elective and >80% are clearly unavoidable.

So, he's a little premature...what's the big deal?

Health care providers have recently recognized that a large segment of the morbidity associated with preterm birth is disproportionately due to the late preterm infant (LPI). One explanation is that this population is the fastest-growing sector of all preterm births. This article describes the epidemiology and etiology of the LPI, and discusses why the LPI is at an increased risk for complications, such as thermal instability, hypoglycemia, feeding difficulties, respiratory distress, hyperbilirubinemia, and sepsis. The need for emergency department visits after hospital discharge and what is currently known regarding neurodevelopmental outcomes are also presented.

Screening for severe neonatal hyperbilirubinemia

Screening for severe neonatal hyperbilirubinemia is integral to newborn care. Predischarge risk assessment relies on documentation of visual jaundice: age at onset and progression; identification of clinical risk such as late prematurity and bruising; with determination of total bilirubin (blood or transcutaneous assay) adjusted for age in hours. Along with promotion of breastfeeding, coordination between birthing hospital and medically supervised outpatient follow-up, a systems approach allows for a safer and effective means to prevent adverse effects of extreme hyperbilirubinemia.

[Late preterm infants: A population at underestimated risk]

BACKGROUND AND OBJECTIVE

There has been a gradual rise in prematurity rates recent years, almost exclusively at the expense of the late preterm (34 to 36 weeks). This population, although with less risk than smaller preterm gestational age, has a morbidity rate significantly higher than term infants. However, there is some underestimation regarding developments in the short and long term. The aim of this study was to look at the incidence of prematurity in our institution and to analyze morbidity and mortality in late preterm compared with term infants

SUBJECTS AND METHODS

We performed a retrospective review of newborns in our Hospital from January 1992 until December 31, 2008. Late preterm group was defined as between 34(0/7) and 36(6/7) weeks gestation (N=2003) and term infants from 37 to 42 weeks gestation (N=32015). We formed 2 subgroups according two time periods (1992-1998 and 2000-2008). The morbidity and mortality for each of the groups and subgroups, and the morbidity from week 34 to 42, were analysed and compared.

RESULTS

During the period studied, the prematurity rate increased from 3.9% to 9.8%, exclusively at the expense of the late preterm (79%). The rate of mortality in late preterm was 5 per thousand compared to 1.1 per thousand in the term (P <0.0001, OR 4.71, 95% CI 2.3-9.5). The incidence of admission to the Neonatal Unit, Cesarean rate, twin, respiratory disorders, need for respiratory support in the form of nasal CPAP or mechanical ventilation, incidence of apnea, jaundice requiring phototherapy, hypoglycaemia and need for parenteral nutrition were significantly higher (P<0.0001) in the late preterm group compared with term infants. The morbidity rate decreased significantly as gestational age increased, with the lowest value from 39 weeks.

CONCLUSIONS

Morbidity and mortality in late preterm infants is significantly higher than in term infants. The guidelines for these near term premature babies need to be reviewed, looking for possible causes of prematurity, and trying to reduce their impact, as well as developing a protocol for their care and close monitoring to minimize the associated morbidity. There should be long-term monitoring to find out the consequences on their psychomotor development. The obstetrics group should be made aware of the true risks of births in the near-term gestational ages.

Identification of neonates at risk for hazardous hyperbilirubinemia: emerging clinical insights

Hyperbilirubinemia is the most common condition requiring evaluation and treatment in neonates. Identifying among all newborns those few at risk to develop marked hyperbilirubinemia is a clinical challenge. Clinical, epidemiologic, and genetic risk factors associated with severe hyperbilirubinemia include late preterm gestational age, exclusive breastfeeding, glucose-6-phosphate dehydrogenase deficiency, ABO hemolytic disease, East Asian ethnicity, jaundice observed in the first 24 hours of life, cephalohematoma or significant bruising, and history of a previous sibling treated with phototherapy. It is increasingly apparent that the etiopathogenesis of severe hyperbilirubinemia is often multifactorial, and emerging evidence suggests that combining risk factor assessment with measurement of predischarge total serum or transcutaneous bilirubin levels will improve hyperbilirubinemia risk prediction.

Health issues of the late preterm infant

"Late preterm" birth is not such an unusual occurrence; in fact these infants were the first group of premature infants who pediatricians learned to treat, and did so with such remarkable success that physicians no longer consider them to be of high risk. So, why the sudden interest in this group? There is now enough evidence that this population is not as benign as previously thought. They have increased mortality when compared to term infants and are at increased risk for complications including transient tachypnea of newborn (TTN), respiratory distress syndrome (RDS), persistent pulmonary hypertension (PPHN), respiratory failure, temperature instability, jaundice, feeding difficulties and prolonged neonatal intensive care unit (NICU) stay. Evidence is currently emerging that late preterm infants make up a majority of preterm births, take up significant resources, have increased mortality/morbidity, and may even have long-term neurodevelopmental consequences secondary to their late prematurity.

Weight for gestational age affects the mortality of late preterm infants

BACKGROUND

Late preterm infant mortality is higher than that for term newborns. The association between weight for gestational age (WGA) category and late preterm mortality has not been well described.

OBJECTIVES

Our objectives for this research were as follows: (1) to compare neonatal and infant mortality rates of SGA, AGA, and LGA late preterm, early term, and term newborns; (2) to determine the relative risk of neonatal and infant death for each WGA category; and (3) to examine causes of neonatal and infant death.

METHODS

We reviewed linked birth and death certificate data for all infants from Utah born between 1999 and 2005 with a GA > or =34 weeks. We calculated neonatal and infant mortality rates for each GA/birth weight stratum and estimated mortality rate ratios using AGA term infants as the reference. International Classification of Diseases, Ninth Revision, codes were used to classify cause of death.

RESULTS

There were 343322 newborns with GA > or =34 weeks from 1999 to 2005. Late preterm SGA infants were approximately 44 times more likely than term AGA newborns to die in their first month and 22 times more likely to die in their first year. When infants dying from congenital conditions were excluded, the differences in mortality rate ratios persisted for SGA infants, especially those born in the late preterm period.

CONCLUSIONS

Being SGA substantially increases the already higher mortality of late preterm and early term newborns. This increased risk cannot be fully explained by an increased prevalence of lethal congenital conditions among SGA late preterm newborns. Clinicians caring for late preterm and early term newborns should be cognizant of their WGA category.

Numbers needed to treat with phototherapy according to American Academy of Pediatrics guidelines

OBJECTIVES

Our aims were to estimate the efficacy of hospital phototherapy for neonatal jaundice and the number needed to treat to prevent one infant from reaching the exchange transfusion level.

METHODS

From a cohort of 281 898 infants weighing > or =2000 g born at > or =35 weeks' gestation at 12 Northern California Kaiser hospitals from 1995 to 2004, we identified 22 547 who had a "qualifying total serum bilirubin level" within 3 mg/dL of the American Academy of Pediatrics 2004 guideline phototherapy threshold. We used multiple logistic regression to estimate the efficacy of hospital phototherapy within 8 hours at preventing the bilirubin level from exceeding the 2004 guideline's exchange transfusion threshold within 48 hours. We combined this efficacy estimate with other predictors of risk to estimate the numbers needed to treat at different values of covariates.

RESULTS

Of the 22 547 eligible newborns, 5251 (23%) received hospital phototherapy within 8 hours of their qualifying bilirubin level. Only 354 (1.6%) ever exceeded the guideline exchange transfusion threshold; 187 (0.8%) did so within 48 hours. Among infants who did not have a positive direct antiglobulin test, hospital phototherapy within 8 hours was highly effective (adjusted odds ratio, 0.16; 95% confidence interval, 0.07-0.34). For infants with bilirubin levels 0-0.9 mg/dL above the phototherapy threshold, the estimated number needed to treat at mean values of covariates was 222 (95% CI: 107-502) for boys and 339 (95% CI: 154-729) for girls, ranging from 10 (95% CI: 6-19) for <24-hour-old, 36-week gestation boys to 3,041 (95% CI: 888-11 096) for > or =3-day-old 41-week girls. Hospital phototherapy was less effective for infants direct antiglobulin test-positive infants (adjusted odds ratio 0.55; 95% CI: 0.21-1.45; P = 0.01 for the direct antiglobulin test x phototherapy interaction).

CONCLUSIONS

While hospital phototherapy is effective, the number needed to treat according to current guidelines varies considerably across different infant subgroups.

Early school-age outcomes of late preterm infants

OBJECTIVE

Late preterm infants represent a significant portion of preterm deliveries. Until recently, these infants have received little attention because of assumptions that they carry minimal risk for long-term morbidities. The purpose of this study was to compare prekindergarten and kindergarten outcomes among healthy late preterm infants, 34 0/7 to 36 6/7 weeks' gestation at birth, and healthy term infants, 37 0/7 to 41 6/7 weeks' gestation at birth.

METHODS

The study sample consisted of singleton infants who were born in Florida between January 1, 1996, and August 31, 1997, with a gestational age between 34 and 41 weeks (N = 161804) with a length of stay < or =72 hours. Seven early school-age outcomes were analyzed. Outcomes were adjusted for 15 potential confounding maternal and infant variables. Unadjusted and adjusted relative risk with 95% confidence interval was estimated for each outcome by using Poisson regression modeling.

RESULTS

Risk for developmental delay or disability was 36% higher among late preterm infants compared with term infants. Risk for suspension in kindergarten was 19% higher for late preterm infants. The remaining 4 outcomes, disability in prekindergarten at 3 and 4 years of age, exceptional student education, and retention in kindergarten, all carried a 10% to 13% increased risk among late preterm infants. The assessment "not ready to start school" was borderline significant.

CONCLUSIONS

This study suggests that healthy late preterm infants compared with healthy term infants face a greater risk for developmental delay and school-related problems up through the first 5 years of life.

Comparison of enrollment in interventional therapies between late-preterm and very preterm infants at 12 months' corrected age

OBJECTIVE

To determine the requirement for therapeutic services of late-preterm infants (34 to 36 weeks' gestation) and morbidities associated with their developmental delays compared with their very preterm (<32 weeks' gestation) counterparts.

METHODS

We used a retrospective cohort study of former preterm children admitted to the neonatal unit who were evaluated at the Regional Neonatal Follow-up Program of Westchester Medical Center in New York at 12 +/- 2 months' corrected age from January 2005 through October 2006. Logistic regression was used to compare odds ratios between late-preterm and very preterm children who qualified for early intervention services. Antenatal, demographic, and neonatal factors were compared between subgroups.

RESULTS

Of the 497 preterm infants evaluated at the Regional Neonatal Follow-up Program, 127 met inclusion criteria (77 very preterm and 50 late-preterm infants). Of the late-preterm infants, 30% qualified for and received early intervention services, 28% physical therapy, 16% occupational therapy, 10% speech therapy, and 6% special education. In the very preterm subgroup, 70% qualified for and received early intervention services, 66% physical therapy, 32% occupational therapy, 32% speech therapy, and 21% special education. Very preterm children were more likely to be enrolled in therapies than their late-preterm counterparts. However, when adjusting for neonatal comorbidities of prematurity, there was no difference in enrollment in early intervention services between the very preterm and late-preterm infants.

CONCLUSIONS

After controlling for comorbidities of prematurity, we found that late-preterm infants requiring admission to the neonatal unit have the same risk as very preterm infants of requiring interventional therapies. This would indicate that it is not only the degree of prematurity but also the morbidities experienced in the neonatal period in conjunction with the period of rapid brain growth that have a profound influence on neurodevelopmental outcomes. This should be considered when planning their hospital discharge and follow-up.

Breastfeeding the late preterm infant

Late preterm infants comprise the fastest growing segment of babies born prematurely. They arrive with disadvantages relative to feeding skills, stamina, and risk for conditions such as hypoglycemia, hyperbilirubinemia, and slow weight gain. Breastfeeding these babies can be difficult and frustrating. Individualized feeding plans include special considerations to compensate for immature feeding skills and inadequate breast stimulation. Breastfeeding management guidelines are described that operate within the late preterm infant's special vulnerabilities.

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.

Complications of the late preterm infant

One of the goals of Healthy People 2010 (set in 1998) was to reduce preterm birthrates from 11.6% to 7.6%. However, in 2004, the preterm birthrate of 12.5% was actually higher than the rate in 1998. Approximately 65% of this increase in prematurity rate is attributed to the increasing birthrate of the late preterm infant. Care of the late preterm infant is far more complicated than many hospital policies and clinical guidelines imply. It cannot be stressed enough to frontline clinicians that late preterm infants are not full-term infants. Their care should not be defined by the same policies and practices that govern term infants. The purpose of this article is to explore the complications that accompany late preterm birth. The following complications will be discussed: thermoregulation challenges, feeding difficulty, late neonatal sepsis, prolonged physiologic jaundice, hypoglycemia, possible neurodevelopmental differences, and respiratory problems.

Late preterm birth: a new nursing issue

Late preterm infants are those born between 34 and 36 6/7 completed weeks' gestation. In the last decade, late preterm infants have become the fastest growing subset of preterm infants and now account for 74% of all preterm births. They are at greater risk for feeding problems, dehydration, hypothermia, jaundice, and hypoglycemia and are more likely to be readmitted to the hospital in the first weeks after birth and accrue greater healthcare costs as a result. Despite the alarming growth of this population and the acknowledgment of increased risk in the literature, there is limited information available to the clinical nurse and few evidence-based guidelines to direct the care of these infants specifically. This article describes what is known to date about this issue and what nurses need to do to appropriately care for late preterm infants.

Toward understanding the connections between infant jaundice and infant feeding

Parents face a paradox when they are told: Breast is best; bottle-feeding is hazardous to health. But breast-fed babies are more likely to become severely jaundiced than bottle-fed babies, and severe jaundice can lead to brain damage. This article will explore the natural physiology of jaundice with a focus on breast-feeding-associated jaundice, primary prevention of hyperbilirubinemia, and current evidence-based recommendations about feeding jaundice breast-fed infants.

Serial brain MRI and ultrasound findings: relation to gestational age, bilirubin level, neonatal neurologic status and neurodevelopmental outcome in infants at risk of kernicterus

AIMS

To describe cranial ultrasound (cUS) and magnetic resonance imaging (MRI) findings in neonates at risk of kernicterus, in relation to gestational age (GA), total serum bilirubin (TSB), age at imaging and neurodevelopmental outcome.

PATIENTS AND METHODS

Neonates with peak TSB > 400 micromol/L and/or signs of bilirubin encephalopathy. Review of neonatal data, cUS, preterm, term and later MRI scans and neurodevelopmental outcome.

RESULTS

11 infants were studied, two < 31, four 34-36 and five 37-40 weeks GA. TSB levels: 235-583 micromol/L (preterms); 423-720 micromol/L (terms). Neonatal neurological examination was abnormal in 8/10. cUS showed increased basal ganglia (BG) in 4/9 infants and white matter (WM) echogenicity, lenticulostriate vasculopathy (LSV) and caudothalamic hyperechogencity/cysts (GLCs) in 5/9 infants. MRI showed abnormal signal intensity (SI) in the globus pallidum (GP) in 1/2 preterm, 8/9 term and 9/11 later scans. Abnormal WM SI occurred in 2 preterm, 7 term and 10/11 later scans. Seven infants developed athetoid/dystonic cerebral palsy (CP) and 6 hearing loss (HL). Adverse outcome was associated with abnormal BG on cUS (3/4 CP, 4/4 HL), with high SI in GP (7/9 CP, 6/9 HL) on late T2-weighted MRI (all GA) and on T1/T2-weighted term MRI, mainly in term-born infants. WM abnormalities, GLCs and LSV did not correlate with outcome.

CONCLUSIONS

Severe CP occurred with relatively low TSB levels in preterms but only at high levels in full-terms; HL was difficult to predict. Early scans did not reliably predict motor deficits whilst all children with CP had abnormal central grey matter on later scans. Abnormal WM was seen early suggesting primary involvement rather than change secondary to grey matter damage. Why characteristic central grey matter MRI features of kernicterus are not seen early remains unexplained.

School outcomes of late preterm infants: special needs and challenges for infants born at 32 to 36 weeks gestation

OBJECTIVE

Because limited long-term outcome data exist for infants born at 32 to 36 weeks gestation, we compared school outcomes between 32- to 33-week moderate preterm (MP), 34-36 week late preterm (LP) and full-term (FT) infants.

STUDY DESIGN

A total of 970 preterm infants and 13 671 FT control subjects were identified from the Early Childhood Longitudinal Study-Kindergarten Cohort. Test scores, teacher evaluations, and special education enrollment from kindergarten (K) to grade 5 were compared.

RESULTS

LP infants had lower reading scores than FT infants in K to first grade (P < .05). Adjusted risk for poor reading and math scores remained elevated in first grade (P < .05). Teacher evaluations of math skills from K to first grade and reading skills from K to fifth grade were worse for LP infants (P < .05). Adjusted odds for below average skills remained higher for math in K and for reading at all grades (P < .05). Special education participation was higher for LP infants at early grades (odds ratio, 1.4-2.1). MP infants had lower test and teacher evaluation scores than FT infants and twice the risk for special education at all grade levels.

CONCLUSIONS

Persistent teacher concerns through grade 5 and greater special education needs among MP and LP infants suggest a need to start follow-up, anticipatory guidance, and interventions for infants born at 32 to 36 weeks gestation.

Israel guidelines for the management of neonatal hyperbilirubinemia and prevention of kernicterus

Despite publication of guidelines for the prevention and management of hyperbilirubinemia in term and late-preterm newborn infants, kernicterus, although rare, continues to occur. Guidelines written for use in one country may not always be universally appropriate. Bearing this in mind, a committee appointed by the Israel Neonatal Society has formulated a set of guidelines, based on those of the American Academy of Pediatrics (2004), but adapted to the realities of the Israeli scene. The guidelines include methods of surveillance of jaundice, prediction of jaundice, assessment of risk factors, discharge planning and post-discharge follow-up, in addition to therapeutic guidelines including indications for phototherapy, exchange transfusion and the use of intravenous immune globulin. Availability of these guidelines to the international community may offer direction to physicians of other countries who may be setting up guidelines for use in their own communities.

The influence of obstetric practices on late prematurity

In this article, the authors review the standard management of several maternal and fetal complications of pregnancy and examine the effect these practices may have on the late preterm birth rate. Given the increasing rate of late preterm birth and the increased recognition of the morbidity and mortality associated with delivery between 34 and 37 weeks, standard obstetric practices and practice patterns leading to late preterm birth should be critically evaluated. The possibility of expectant management of some pregnancy complications in the late preterm period should be investigated. Furthermore, prospective research is warranted to investigate the role of antenatal corticosteroids beyond 34 weeks.

Management of jaundice and prevention of severe neonatal hyperbilirubinemia in infants >or=35 weeks gestation

Kernicterus is still occurring but should be largely preventable if health care personnel follow the recommendations listed in this guideline. These recommendations emphasize the importance of universal, systematic assessment of the risk of severe hyperbilirubinemia, lactation support, close follow-up, and prompt intervention when necessary. A systems-based approach to prevent severe neonatal hyperbilirubinemia should be implemented at all birthing facilities and coordinated with continuing ambulatory care. Translational research is needed to better understand the mechanisms of bilirubin neurotoxicity and potential therapeutic interventions.

An evidence-based review of hyperbilirubinemia in the late preterm infant, with implications for practice: management, follow-up, and breastfeeding support

As the incidence of late preterm births continues to rise, health care providers need to be aware of this population's unique needs. This review focuses on the additional risks late preterm infants encounter related to unconjugated hyperbilirubinemia and the importance of breastfeeding support and follow-up. Additional, population-based studies concentrating on the late preterm infant are needed to determine more clearly the incidence of hyperbilirubinemia, with specific levels documented; incidence of ED visits and rehospitalizations related to hyperbilirubinemia; and incidence of bilirubin neurotoxicity with both short- and long-term follow-up. It is also important to study these outcomes in relation to the nature and degree of risk associated with early discharge, insufficient follow-up, and breastfeeding. Future research is needed to develop evidence-based recommendations for optimal discharge timing, counseling, and postdischarge follow-up of late preterm infants, particularly those who are breastfed, to promote safe patient care.

Preventing kernicterus: a wake-up call

Perspective on the paper by Manning et al (see page 342)

Elective cesarean section and induction and their impact on late preterm births

At all gestational ages, the risks of continuing a pregnancy must be carefully balanced against the risks of delivery and the associates risk of prematurity. This concept is of increasing importance in late preterm pregnancy when medical or obstetric complications frequently warrant delivery and the risk of prematurity persists. Given that morbidity exists for infants born between 34 and 37 weeks gestations, efforts should be focused on minimizing the late preterm birth rate and at improving the outcome of these infants. Published guidelines outlining the appropriate timing of elective induction of labor and elective Cesarean section should be closely followed to avoid unintended iatrogenic prematurity. Research should continue to investigate the etiology of spontaneous preterm deliveries and aim to develop strategies of primary prevention. The incidence and etiology of iatrogenic late preterm birth should also be further investigated and alternative management strategies should be considered. To gain information about the impact of elective delivery on late preterm births, the data collected from birth records should reflect the changing obstetric practices in the United States and be revised to include specific information on elective deliveries.

Neurodevelopmental outcome of the late preterm infant

There is very limited information about the developmental outcome of the late preterm infant. The developing brain is vulnerable to injury during this very active and important stage of fetal brain development; therefore, it is important to carefully monitor the neurologic outcome of these infants. This article discusses gestational brain development and complications of late preterm birth that contribute to the overall risk of brain injury.

Hyperbilirubinemia and bilirubin toxicity in the late preterm infant

Late preterm gestation is an important risk factor for the development of severe neonatal hyperbilirubinemia and kernicterus. An exaggerated hepatic immaturity contributes to the greater prevalence, severity, and duration of neonatal jaundice in late preterm infants. Breast milk feeding is almost uniformly present and large for gestational age status, male sex, and G6PD deficiency are over-represented among that cohort of late preterm infants with kernicterus. Attention to screening measures for jaundice in the newborn nursery, the provision of lactation support, parental education, timely postdischarge follow-up, and appropriate treatment when clinically indicated should help to reduce the risk of late preterm neonates developing severe neonatal jaundice or kernicterus.

Optimizing care and outcome for late-preterm (near-term) infants: a summary of the workshop sponsored by the National Institute of Child Health and Human Development

In 2003, 12.3% of births in the United States were preterm (< 37 completed weeks of gestation). This represents a 31% increase in the preterm birth rate since 1981. The largest contribution to this increase was from births between 34 and 36 completed weeks of gestation (often called the "near term" but referred to as "late preterm" in this article). Compared with term infants, late-preterm infants have higher frequencies of respiratory distress, temperature instability, hypoglycemia, kernicterus, apnea, seizures, and feeding problems, as well as higher rates of rehospitalization. However, the magnitude of these morbidities at the national level and their public health impact have not been well studied. To address these issues, the National Institute of Child Health and Human Development of the National Institutes of Health invited a multidisciplinary team of experts to a workshop in July 2005 entitled "Optimizing Care and Outcome of the Near-Term Pregnancy and the Near-Term Newborn Infant." The participants discussed the definition and terminology, epidemiology, etiology, biology of maturation, clinical care, surveillance, and public health aspects of late-preterm infants. Knowledge gaps were identified, and research priorities were listed. This article provides a summary of the meeting.