Neurodevelopmental outcome of late-preterm infants: Literature review

Postnatal functional integrity of the brainstem auditory pathway in late preterm infants born of small-for-gestation age: how different from those born of appropriate-for-gestation

It is unclear whether there is any postnatal abnormality in brainstem auditory function in late preterm small-for-gestational-age (SGA) infants. We investigated the functional integrity of the brainstem auditory pathway at 4 months after term in late preterm SGA infants and defined differences from appropriate-for-gestational age (AGA) infants. The maximum length sequence brainstem evoked response (MLS BAER) was recorded and analyzed in 24 SGA (birthweight < 3rd centile) infants and 28 AGA infants (birthweight > 10th centile). All infants were born at 33-36-week gestation without major perinatal and postnatal problems. We found that I-V interval in SGA infants was shorter than in AGA infants at higher click rates and significantly shorter at the highest rate of 910/s. Of the two smaller intervals, I-III interval was significantly shorter in SGA infants than in AGA infants at higher click rates of 455 and 910/s clicks, whereas III-V interval was similar in the two groups. The III-V/I-III interval ratio in SGA infants tended to be greater than in AGA infants at all rates and was significantly greater at 455 and 910/s clicks. The slope of I-III interval-rate functions in SGA infants was moderately smaller than in AGA infants.  Conclusions: The main and fundamental difference between late preterm SGA and AGA infants was a significant shortening in the MLS BAER I-III interval in SGA infants at higher click rates, suggesting moderately faster neural conduction in the caudal brainstem regions. Postnatal neural maturation in the caudal brainstem regions is moderately accelerated in late preterm SGA infants. What is Known: • At 40 weeks of postconceptional age, late preterm SGA infants manifested a mild delay in neural conduction in the auditory brainstem. What is New: • At 56 weeks of postconceptional age, late preterm SGA infants manifested moderately faster neural conduction in the caudal brainstem regions. • Postnatal neural maturation is moderately accelerated in the caudal brainstem regions of late preterm SGA infants.

Process and Outcome Measures for Infants Born Moderate and Late Preterm in Tertiary Canadian Neonatal Intensive Care Units

OBJECTIVE

To describe the prevalence of and between-center variations in care practices and clinical outcomes of moderate and late preterm infants (MLPIs) admitted to tertiary Canadian neonatal intensive care units (NICUs).

STUDY DESIGN

This was a retrospective cohort study including infants born at 320/7 through 366/7 weeks of gestation and admitted to 25 NICUs participating in the Canadian Neonatal Network between 2015 and 2020. Patient characteristics, process measures represented by care practices, and outcome measures represented by clinical in-hospital and discharge outcomes were reported by gestational age weeks. NICUs were compared using indirect standardization after adjustment for patient characteristics.

RESULTS

Among 25 669 infants (17% of MLPIs born in Canada during the study period) included, 45% received deferred cord clamping, 7% had admission hypothermia, 47% received noninvasive respiratory support, 11% received mechanical ventilation, 8% received surfactant, 40% received antibiotics in the first 3 days, 4% did not receive feeding in the first 2 days, and 77% had vascular access. Mortality, early-onset sepsis, late-onset sepsis, or necrotizing enterocolitis occurred in <1% of the study cohort. Median (IQR) length of stay was 14 (9-21) days among infants discharged home from the admission hospital and 5 (3-9) days among infants transferred to community hospitals. Among infants discharged home, 33% were discharged on exclusive breastmilk and 75% on any breastmilk. There were significant variations between NICUs in all process and outcome measures.

CONCLUSIONS

Care practices and outcomes of MLPIs varied significantly between Canadian NICUs. Standardization of process and outcome quality measures for this population will enable benchmarking and research, facilitating systemwide improvements.

A comparison of the effect of procedural pain on cerebral oxygen saturation between late preterm and term infants

OBJECTIVES

We prospectively compared cerebral oxygen saturation (CrSO2) and pain score changes during procedures in late preterm (LPT) versus term infants.

METHODS

Near-infrared spectroscopy, pulse oximetry, Neonatal Infant Pain Scale (NIPS) and Premature Infant Pain Profile-Revised (PIPP-R) scores were assessed and CrSO2 data analyzed.

RESULTS

Thirty infants in each group were evaluated. LPT infants displayed a milder significant drop in Minimum post-procedural CrSO2 and smaller Maximum-Minimum post-procedural CrSO2 disparity. CrSO2 minute changes between the groups were non-significant. Moderate correlations were observed in both groups between NIPS and Minimum post-procedural CrSO2, and a moderate correlation was found in the Maximum-Minimum post-procedural CrSO2 difference in LPT infants. No correlation between PIPP-R and CrSO2 values was noted.

CONCLUSION

LPT and term infants demonstrated decreased CrSO2 in response to painful procedures. Correlations between CrSO2 and PIPP-R or NIPS scores were poor to moderate, reflecting the complex nature of these associations relative to gestational age.

Suboptimal postnatal function of brainstem auditory pathway in late preterm infants who do not have major perinatal and postnatal complications

OBJECTIVES

To examine postnatal functional status of the brainstem auditory pathway in late preterm infants and detect any postnatal auditory abnormality.

METHODS

Thirty preterm infants born at 33-36 weeks gestation were studied three months after term. None had major perinatal and postnatal complications to minimize confounding effects. Brainstem auditory evoked responses were recorded with 21-91/s clicks.

RESULTS

Compared with postnatal age-matched normal term infants, the late preterm infants did not manifest any major abnormalities in brainstem auditory evoked responses at conventionally used 21/s clicks. At higher click rates, however, the late preterm infants manifested a moderate prolongation in BAER wave V latency. All interpeak intervals tended to be prolonged at higher click rates. The I-V interval was significantly prolonged at 51/s and particularly at 91/s clicks. Both the I-III and III-V intervals were significantly prolonged at 91/s. The late preterm infants also manifested reduced amplitudes of BAER waves III and V at most click rates.

CONCLUSION

The central components of the brainstem auditory evoked responses were abnormal at higher click rates three months after term in the late preterm infants. Postnatal brainstem auditory function is suboptimal in late preterm infants without major complications. This suboptimal brainstem auditory function may not be clearly shown at term or an earlier stage, but can be shown later. Late preterm infants, although they may not have major complications, should be followed for later auditory development, providing valuable information for improving postnatal care.

Cortisol reactivity and negative affect among preterm infants at 12 months during a mother-infant interaction task

The purpose of this study was to investigate correlates of preterm (PT) infant's cortisol reactivity and the association to infant negative affect, during a mother-infant interaction procedure. Participants included 48 infants born prematurely (gestational age < 37 weeks) and their mothers, assessed when infants were 12 months old corrected for prematurity. The examined variables comprised both neonatal and environmental dimensions including maternal interactive behavior. Infant negative affect and maternal interactive behavior were assessed with a standardized mother-infant interaction task. A baseline infant saliva sample was collected before the interaction began, and a second sample after the interaction episodes ended. Results revealed that decrease of infant's cortisol concentration was significantly associated with the exposure to more sensitive, and less intrusive maternal behaviors. However, once controlled for neonatal risk, family SES and maternal psychological distress, the associations were rendered non-significant. Although the association between cortisol reactivity and negative affect trended toward significance, maternal intrusiveness was the only significant predictor of observed infant negative affect. Findings suggest the importance of primary relational experiences on PT infants' early regulatory competencies.

Feasibility and Safety of Continuous Glucose Monitoring in Infants at Risk of Hypoglycemia in a Rooming-in Setting

Background:Screening of neonatal hypoglycemia uses currently intermittent blood sampling. Continuous glucose monitoring (CGM) allows for tighter glucose control and better comfort for newborns and parents. CGM has previously been used in intensive care setting or blinded to clinicians. Our pilot study uses CGM in real time in rooming-in setting. Methods: CGM was attached within first two hours of life. Low glucose readings were verified to prevent overtreatment. Pairs of sensor readings and corresponding blood glucose measurements were assessed retrospectively. Neurodevelopmental evaluation was performed at 24 months. Results: 44 infants were enrolled. Three had verified hypoglycemia found due to CGM. No patient was below 2 standard deviations in any components of Bayley scales. Median scores were: Cognitive 100, language 86, motor 94. Conclusion: Use of CGM in a rooming-in environment is safe from clinical and neurodevelopmental point of view. Randomized trials are needed to evaluate superiority in longer term outcomes.

Supporting Feeding of Late Preterm Infants in the Hospital: A Quality Improvement Project

BACKGROUND

Feeding difficulty is the most common cause of delayed hospital discharge and readmission of late preterm infants. Frequent and adequate feedings from birth are protective against dehydration, hypoglycemia, and jaundice. The National Perinatal Association's feeding guidelines provide the foundation for late preterm infant standards of care. Feeding at least every 3 hours promotes nutritional status and neurologic development. One feeding assessment every 12 hours during the hospital stay can ensure quality of infant feeding.

PROBLEM

At a large urban hospital, medical record reviews were completed to evaluate nursing care practices consistent with the hospital's late preterm infant care standard policy. Feeding frequency and nurse assessment of feeding effectiveness were far below acceptable targets. A quality improvement team was formed to address inconsistency with expected practice.

METHODS

The project included an investigation using the define, design, implement, and sustain method of quality improvement. Parent education, nurse education, and visual cues were developed to sustain enhanced nursing practice.

RESULTS

Late preterm infants who received feedings at least every 3 hours increased from 2.5% (1 of 40) to 27% (11 of 40); (M = 0.275, SD = 0.446), p = 0.001. Documented breastfeeding assessments increased from 2% (5 of 264) to 8% (10 of 126), p = 0.001. Documented bottle-feeding assessments increased from 15% (39 of 264) to 31% (53 of 172), p < 0.001. Intervention time was cut short due to reprioritization of efforts in response to the COVID-19 pandemic.

CONCLUSION

Interventions and implementation of this process improvement is easy to replicate through attainable and sustainable goals directed toward improved outcomes for late preterm infants.

Prediction Effect of Amplitude-Integrated EEG on the Brain Damage and Long-Term Nervous System Development of Late Preterm Infants

In order to explore the prediction effect of amplitude-integrated EEG on the brain damage and long-term nervous system development of late preterm infants, this paper uses the hospital's late preterm infants as the research object and analyzes the prediction effect of amplitude-integrated EEG on the brain damage and long-term nervous system development of late preterm infants through controlled trials. Among them, the test group used amplitude-integrated EEG for prediction analysis, and the control group used traditional clinical prediction methods. Furthermore, the real-time monitoring and short-term prediction effects of amplitude-integrated EEG on brain damage in late preterm babies and the prediction impact on long-term nervous system development are evaluated in this study. It incorporates statistical techniques to evaluate the findings statistically. In addition, a nonparametric rank-sum test is used in this work, and a chi-square test is used to compare enumeration data across groups. Through experimental research, it can be seen that the amplitude-integrated EEG has a pronounced prediction effect on the brain damage and long-term nervous system development of late preterm infants, and the effect is higher than that of the traditional clinical prediction methods.

Growth and neurodevelopment in low birth weight versus normal birth weight infants from birth to 24 months, born in an obstetric emergency hospital in Haiti, a prospective cohort study

BACKGROUND

Low birthweight (LBW) infants are at higher risk of mortality and morbidity (growth, chronic disease and neurological problems) during their life. Due to the high incidence of (pre-) eclampsia in Haiti, LBW infants are common. We assessed the anthropometric growth (weight and length) and neurodevelopmental delay in LBW and normal birthweight (NBW) infants born at an obstetric emergency hospital in Port au Prince, Haiti, between 2014 and 2017.

METHODS

Infants were followed at discharge and 3, 6, 12, 15, 18, 21 and 24 months of corrected gestational age. At each visit they underwent a physical checkup (weight, length, physical abnormalities, identification of morbidities). At 6, 12, 18 and 24 months they underwent a neurodevelopmental assessment using the Bayley Scale III (motor, cognitive and communication skills). We modelled the trajectories between birth and 24 months of age of NBW compared to LBW infants for weight, length, and raw scores for Bayley III assessments using mixed linear models.

RESULTS

In total 500 LBW and 210 NBW infants were recruited of which 333 (46.7%) were followed up for 24 months (127 NBW; 60.5% and 206 LBW; 41.2%) and 150 died (LBW = 137 and NBW = 13). LBW and NBW babies gained a mean 15.8 g and 11.4 g per kg of weight from discharge per day respectively. The speed of weight gain decreased rapidly after 3 months in both groups. Both groups grow rapidly up to 6 months of age. LBW grew more than the NBW group during this period (22.8 cm vs. 21.1 cm). Both groups had WHZ scores <- 2 up to 15 months. At 24 months NBW babies scored significantly higher on the Bayley scales for gross motor, cognitive and receptive and expressive communication skills. There was no difference between the groups for fine motor skills.

CONCLUSION

LBW babies that survive neonatal care in urban Haiti and live up to 24 months of age, perform similar to their NBW for weight, length and fine motor skills. LBW babies are delayed in gross motor, cognitive and communication skills development. Further research on the clinical significance of these findings and long term implications of this neurodevelopmental delay is needed.

Progesterone for prevention of preterm birth in women with short cervical length: 2-year infant outcomes

OBJECTIVE

To evaluate the long-term outcomes of children born to women with a short cervix and otherwise low risk for preterm birth, after antenatal exposure to vaginal progesterone vs placebo.

METHODS

This was a follow-up study of the Triple P trial, which randomized 80 low-risk women with a short cervix (≤ 30 mm) at 18-22 weeks' gestation to progesterone (n = 41) or placebo (n = 39). At 2 years of corrected age, children were invited for a neurodevelopmental assessment, using the Bayley Scales of Infant and Toddler Development, third edition (BSID-III), and a neurological and physical examination by an assessor blinded to the allocated treatment. Parents filled out the Ages and Stages Questionnaire, the Child Behavior Checklist (CBCL) and a general-health questionnaire. The main outcome of interest was mean BSID-III cognitive and motor scores. Additionally, a composite score of mortality and abnormal developmental outcome, including BSID-III ≤-1 SD, CBCL score in the clinical range and/or parental reported physical problems (at least two operations or at least two hospital admissions in the previous 2 years), was evaluated. Our sample size, dictated by the original sample of the Triple P trial, provided 80% power to detect a mean difference (MD) of 15 points (1 SD) between groups for the BSID-III tests.

RESULTS

Of the 80 children born to the randomized women, one in the progesterone group and two in the placebo group died in the neonatal period. Follow-up data were obtained for 59/77 (77%) children and BSID-III outcomes in 57 children (n = 28 in the progesterone group and n = 29 in the placebo group) born at a median gestational age of 38 + 6 weeks (interquartile range (IQR), 37 + 3 to 40 + 1 weeks) with a median birth weight of 3240 g (IQR, 2785-3620 g). In the progesterone vs placebo groups, mean BSID-III cognitive development scores were 101.6 vs 105.0 (MD, -3.4 (95% CI, -9.3 to 2.6); P = 0.29) while mean motor scores were 102.4 vs 107.3 (MD, -4.9 (95% CI, -11.2 to 1.4); P = 0.13). No differences were seen between the two groups in physical (including genital and neurological examination), behavioral and health-related outcomes.

CONCLUSION

In this sample of children born to low-risk women with a short cervix at screening, no relevant differences in neurodevelopmental, behavioral, health-related and physical outcomes were found between offspring exposed to vaginal progesterone and those exposed to placebo. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Early Neurological Assessment and Long-Term Neuromotor Outcomes in Late Preterm Infants: A Critical Review

Background and Objectives: Late preterm (LP) infants (born between 34 and 36 weeks of gestational age) are considered at higher risk of neonatal morbidities, mortality, and neurological impairments than full-term born infants (FT). The aim of this study was to provide a critical review of the literature outlining the different aspects of neurological function reported both in the neonatal period and in the follow up of late preterm infants. Materials and Methods: A comprehensive search of the MEDLINE, Embase, PsycINFO, and CINAHL electronic databases was made, using the following search terms: ‘Late preterm infants’, ‘Near term infants’, ‘neurological assessment’, ‘neurological outcome’, ‘neuromotor outcome’, cerebral palsy’, ‘CP’, ‘motor impairment’, including all the studies reporting clinical neurological assessment of LP (including both neonatal period and subsequent ages). Results: A total of 35 articles, comprising 301,495 children, were included as fulfilling the inclusion criteria: ten reported neonatal neurological findings, seven reported data about the first two years after birth, eighteen reported data about incidence of CP and motor disorder during the infancy. Results showed a more immature neurological profile, explored with structured neurological assessments, in LP infants compared with FT infants. The LP population also had a higher risk of developing cerebral palsy, motor delay, and coordination disorder. Conclusion: LP had a higher risk of neurological impairments than FT infants, due to a brain immaturity and an increased vulnerability to injury, as the last weeks of gestational age are crucial for the development of the brain.

Maternal dietary intake of fish and PUFAs and child neurodevelopment at 6 months and 1 year of age: a nationwide birth cohort-the Japan Environment and Children's Study (JECS)

BACKGROUND

Although emerging evidence indicates a relation between maternal intake of fish and improved child neurodevelopment, the results are inconsistent.

OBJECTIVES

This study investigated whether dietary consumption of fish during pregnancy is associated with offspring neurodevelopment at age 6 mo and 1 y. As exploratory research, we also examined the association between consumption of PUFAs and neurodevelopment at the same time points.

METHODS

After exclusion and multiple imputation from a dataset comprising 104,065 records from the Japan Environment and Children's Study, we evaluated 81,697 and 77,751 mother-child pairs at age 6 mo and 1 y, respectively.

RESULTS

Maternal fish intake during pregnancy was independently associated with reduced risk of delay in problem-solving at age 6 mo (lowest compared with highest quintile OR = 0.88; 95% CI: 0.79, 0.99; P-trend = 0.01) and in fine motor skills (highest quintile OR = 0.90; 95% CI: 0.81, 0.99; P-trend = 0.02) and problem-solving (fourth quintile OR = 0.89; 95% CI: 0.81, 0.98; and highest quintile OR = 0.90; 95% CI: 0.81, 0.99; P-trend = 0.005) at age 1 y. Dietary intake of total n-3 PUFAs was associated with reduced risk of delay in fine motor skills at 6 mo, and in fine motor skills and problem-solving at 1 y. Dietary intake of total n-6 PUFAs was associated with reduced risk of delay in communication and fine motor skills at 6 mo, and in gross motor skills, fine motor skills, and problem-solving at 1 y. In contrast, the dietary n-6/n-3 ratio was positively associated with increased risk of delay in problem-solving at 1 y.

CONCLUSIONS

The results of this study suggest there might be beneficial effects of fish intake during pregnancy on some domains of child psychomotor development and this effect might be partially explained by PUFA intake from fish. Trial registration: UMIN000030786.

[Neuropsychological development of late preterm infants and early term infants at the age of 1 year: a follow-up study]

OBJECTIVE

To study the level of neuropsychological development in late preterm infants and early term infants at the age of 1 year.

METHODS

A total of 1 257 children with a corrected age of 1 year were enrolled as subjects. According to gestational age at birth, they were divided into an early preterm group (28-33⁺⁶ weeks), a late preterm group (34-36⁺⁶ weeks), an early term group (37-38⁺⁶ weeks), and a full-term group (39-41⁺⁶ weeks). Gesell Developmental Schedules were used to assess the neuropsychological development of the children, and the groups were compared in terms of neuropsychological development at the age of 1 year.

RESULTS

There were significant differences in the developmental quotients of the five functional areas (adaptability, gross motor, fine motor, language and social ability) between the four groups at the age of 1 year (P<0.05), and the full-term infants had the highest development quotients, followed by the early term infants, the late preterm infants, and the early preterm infants (P<0.05). The full-term infants had the lowest rate of developmental delay in each functional area, while the early preterm infants had the highest rate (P<0.05). Compared with the full-term infants, the early term infants had a higher risk of developmental delay in adaptability (OR=1.796, P<0.05), and the late preterm infants had a higher risk of developmental delay in adaptability (OR=2.651, P<0.05) and fine motor (OR=2.679, P<0.05), while the early preterm infants had a higher risk of developmental delay in adaptability (OR=4.069, P<0.05), fine motor (OR=3.710, P<0.05), and social ability (OR=3.515, P<0.05).

CONCLUSIONS

The risk of neuropsychological developmental delay decreases with the increase in gestational age in children at the age of 1 year, with a dose-response effect. There are varying degrees of developmental delay in early term infants and late preterm infants, and health care follow-up for early term infants and late preterm infants should be taken seriously.