Establishing feasibility and reliability of subcutaneous fat measurements by ultrasound in very preterm infants.

BACKGROUND: Regional fat distribution may be a marker of metabolic health and brain growth in preterm infants. Point of care ultrasound has been used to assess regional fat in term infants but has not been used widely in preterm infants. OBJECTIVE: To longitudinally quantify changes in body composition metrics using bedside ultrasound in very preterm infants. STUDY DESIGN: Very preterm infants (N = 69) were enrolled after birth and body composition assessments were done through 36 completed weeks' postmenstrual age (PMA). Linear mixed effects regression was used to model change in body composition assessments over time. RESULTS: There was an average increase across PMA for each body composition outcome. Biceps ultrasound subcutaneous fat (SQF) thickness increased by 0.11 mm (95% CI: 0.09, 0.13) each postmenstrual week. Triceps, subscapular, and abdominal ultrasound SQF remained constant through 28 weeks' PMA, then increased each week through 36 completed weeks' PMA. The inter-rater and intra-rater intraclass correlation coefficients for the ultrasound SQF measures ranged from 85.8 to 99.9. CONCLUSION: Use of ultrasound as a novel method to assess regional fat distribution in very preterm infants is feasible and reliable. IMPACT: Regional fat distribution may be a marker of metabolic health and brain growth in preterm infants. Gold standard body composition assessments may not be feasible in medically fragile very preterm infants. This study assesses longitudinally changes in regional adiposity development using bedside ultrasound techniques in a multicenter cohort of very preterm infants. Results of this study show that bedside ultrasound as a novel method to assess regional subcutaneous fat distribution and development in very preterm infants is both feasible and reliable.

Point-of-care human milk concentration by passive osmosis: comprehensive analysis of fresh human milk samples.

OBJECTIVE: Preterm infants need enrichment of human milk (HM) for optimal growth. This study evaluated a novel, point-of-care human milk concentration (HMC) process for water removal from fresh HM samples by passive osmotic concentration. STUDY DESIGN: Nineteen fresh HM samples were concentrated by incubation with the HMC devices for 3 h at 4 °C. Pre- and post-concentration HM samples were compared by HM properties for: pH, osmolality, macronutrients, enzyme activity, bioactive, and total cell viability. RESULTS: Passive osmotic concentration reduced HM volume by an average of 16.3% ± 3.8% without a significant effect on pH or cell viability. Ten of the 41 HM components did not differ significantly (p > 0.05) between pre- and post-concentration samples. Twenty-three increased within the expected range by volume reduction. Six increased more than expected, two less than expected, and none decreased significantly. CONCLUSION: Passive osmotic concentration of fresh HM can concentrate HM components by selective removal of water. HM osmolality and pH remained within neonatal feeding parameters.

Maternal stress and breastfeeding outcomes in the NICU couplet care experience: a prospective cohort study.

OBJECTIVE: Couplet care is an innovative approach to provide postpartum care in the neonatal intensive care unit (NICU) with little known about its impact on infant feeding outcomes and maternal stress. STUDY DESIGN: We compared breastfeeding outcomes and maternal NICU-related stress among mother-infant dyads based on exposure to couplet care in a prospective cohort study. RESULT: Among 19 couplet-care exposed (CCE) dyads and 19 traditional postpartum care dyads, CCE mothers had lower self-reported stress related to parent-infant relationship as compared to traditional care (P < 0.001). CCE infants received relatively more feeds at the breast (P < 0.001), more breastmilk feeds (P = 0.002), and fewer feeds by staff (P < 0.001). Adjusted for gestational age, marital status, and infant length of stay, couplet care was associated with being in a higher tertile of percent breastmilk feeds (aOR 7.29, 95% CI 1.45-36.65). CONCLUSION: NICU couplet care was associated with improved parental stress and breastfeeding outcomes during hospitalization.

Parent and grandparent neonatal intensive care unit visitation for preterm infants.

OBJECTIVE: Characterize family NICU visitation and examine associations with maternal health and social factors and infant health outcomes. STUDY DESIGN: Retrospective cohort study of 167 infants born ≤32 weeks at two urban NICUs 01/2019-03/2020. Average nurse-documented family member visitation and associations of visitation with maternal and infant factors and outcomes were compared. RESULTS: Mothers visited 4.4 days/week, fathers 2.6 days/week, and grandparents 0.4 days/week. Older maternal age, nulliparity, and non-English primary language were associated with more frequent family visitation. Mothers with depression or anxiety history visited less. Maternal depression and public insurance were associated with fewer father visits. Low parental visitation was associated with lower odds of feeding any maternal milk at discharge and low maternal visitation with 11.5% fewer completed infant subspecialty appointments in the year following discharge (95% CI -20.0%, -3.0%). CONCLUSION: Families with social disadvantage visited less often. Parental visitation was associated with infant feeding and follow-up.

Early brain microstructural development among preterm infants requiring caesarean section versus those delivered vaginally.

It is known that the rate of caesarean section (C-section) has been increasing among preterm births. However, the relationship between C-section and long-term neurological outcomes is unclear. In this study, we utilized diffusion tensor imaging (DTI) to characterize the association of delivery method with brain white matter (WM) microstructural integrity in preterm infants. We retrospectively analyzed the DTI scans and health records of preterm infants without neuroimaging abnormality on pre-discharge term-equivalent MRI. We applied both voxel-wise and tract-based analyses to evaluate the association between delivery method and DTI metrics across WM tracts while controlling for numerous covariates. We included 68 preterm infants in this study (23 delivered vaginally, 45 delivered via C-section). Voxel-wise and tract-based analyses revealed significantly lower fractional anisotropy values and significantly higher diffusivity values across major WM tracts in preterm infants delivered via C-section when compared to those delivered vaginally. These results may be partially, but not entirely, mediated by lower birth weight among infants delivered by C-section. Nevertheless, these infants may be at risk for delayed neurodevelopment and could benefit from close neurological follow up for early intervention and mitigation of adverse long-term outcomes.

Diabetes in Pregnancy, Neonatal Morbidities, and Early Growth in Moderate or Late Preterm Infants.

OBJECTIVES: To compare differences in short term morbidities and early growth among moderate and late preterm infants of mothers with and without diabetes (DM) in pregnancy. METHODS: In a longitudinal analysis using data from the Pediatrix Clinical Data Warehouse of preterm infants (born 32 0/7 to 36 6/7 weeks) discharged from neonatal intensive care units from 2008 to 2019, health characteristics were compared between DM exposure groups. Change in growth from birth to discharge were compared using linear mixed effects modeling. RESULTS: Among 301 499 moderate and late preterm infants in the analysis, 14% (N = 42 519) were exposed to DM in pregnancy. Incidence of congenital anomalies, hypoglycemia, and hyperbilirubinemia were higher in DM-group (P < .001), and DM-group was more likely to need respiratory support in the first postnatal days (P = .02). Percent weight change from birth differed by gestational age, such that 36-week DM-group infants remained on average 2% (95% confidence interval [CI]: 1.57 to 2.41) below birth weight on day 14, whereas 32-week DM-group infants were on average 2.1% (95% CI: 1.69 to 2.51) above birth weight on day 14. In the regression analysis, DM-group had faster weight loss in the first postnatal week when stratified by gestational age. The adjusted difference in weight velocity (g per day) from days 0 to 3 was -4.5 (95% CI: -5.1 to -3.9), -6.5 (95% CI: -7.4 to -5.7), and -7.2 (95% CI: -8.2 to -6.2) for infants born 34-, 35-, and 36-weeks, respectively. CONCLUSIONS: In moderate or late preterm infants, diabetes in pregnancy is associated with common neonatal morbidities. Examination of intensive care nutritional practices may identify reasons for observed differences in weight trajectories by gestational age and diabetes exposure.

Early brain microstructural development among preterm infants requiring caesarean section versus those delivered vaginally.

It is known that the rate of caesarean section (C-section) has been increasing among preterm births. However, the relationship between C-section and long-term neurological outcomes is unclear. In this study, we utilized diffusion tensor imaging (DTI) to characterize the association of delivery method with brain white matter (WM) microstructural integrity in preterm infants. We retrospectively analyzed the DTI scans and health records of preterm infants without neuroimaging abnormality on pre-discharge term-equivalent MRI. We applied both voxel-wise and tract-based analyses to evaluate the association between delivery method and DTI metrics across WM tracts while controlling for numerous covariates. We included 68 preterm infants in this study (23 delivered vaginally, 45 delivered via C-section). Voxel-wise and tract-based analyses revealed significantly lower fractional anisotropy values and significantly higher diffusivity values across major WM tracts in preterm infants delivered via C-section when compared to those delivered vaginally. These results may be partially, but not entirely, mediated by lower birth weight among infants delivered by C-section. Nevertheless, these infants may be at risk for delayed neurodevelopment and could benefit from close neurological follow up for early intervention and mitigation of adverse long-term outcomes.

Nutrition Management of High-Risk Neonates After Discharge.

Nutrition management of the high-risk infant after hospital discharge is complicated by the infant's dysfunctional or immature oral feeding skills, nutritional deficits, and the family's feeding plan. Although evidence is limited, available studies point to developing an individualized nutritional plan, which accounts for these factors; protects and prioritizes the family's plan for breastfeeding; and promotes an acceptable growth pattern. Further research is needed to identify the type and duration of posthospital discharge nutrition to optimize high-risk infant neurodevelopment and body composition. Attention to infant growth, lactation support, and safe feed preparation practices are critical in the transition to home.

Impact of postnatal weight gain on brain white matter maturation in very preterm infants.

BACKGROUND AND PURPOSE: Very preterm infants (VPIs, <32 weeks gestational age at birth) are prone to long-term neurological deficits. While the effects of birth weight and postnatal growth on VPIs' neurological outcome are well established, the neurobiological mechanism behind these associations remains elusive. In this study, we utilized diffusion tensor imaging (DTI) to characterize how birth weight and postnatal weight gain influence VPIs' white matter (WM) maturation. METHODS: We included VPIs with complete birth and postnatal weight data in their health record, and DTI scan as part of their predischarge Magnetic Resonance Imaging (MRI). We conducted voxel-wise general linear model and tract-based regression analyses to explore the impact of birth weight and postnatal weight gain on WM maturation. RESULTS: We included 91 VPIs in our analysis. After controlling for gestational age at birth and time between birth and scan, higher birth weight Z-scores were associated with DTI markers of more mature WM tracts, most prominently in the corpus callosum and sagittal striatum. The postnatal weight Z-score changes over the first 4 weeks of life were also associated with increased maturity in these WM tracts, when controlling for gestational age at birth, birth weight Z-score, and time between birth and scan. CONCLUSIONS: In VPIs, birth weight and post-natal weight gain are associated with markers of brain WM maturation, particularly in the corpus callosum, which can be captured on discharge MRI. These neuroimaging metrics can serve as potential biomarkers for the early effects of nutritional interventions on VPIs' brain development.

Infant factors that impact the ecology of human milk secretion and composition-a report from "Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN)" Working Group 3.

Infants drive many lactation processes and contribute to the changing composition of human milk through multiple mechanisms. This review addresses the major topics of milk removal; chemosensory ecology for the parent-infant dyad; the infant's inputs into the composition of the human milk microbiome; and the impact of disruptions in gestation on the ecology of fetal and infant phenotypes, milk composition, and lactation. Milk removal, which is essential for adequate infant intake and continued milk synthesis through multiple hormonal and autocrine/paracrine mechanisms, should be effective, efficient, and comfortable for both the lactating parent and the infant. All 3 components should be included in the evaluation of milk removal. Breastmilk "bridges" flavor experiences in utero with postweaning foods, and the flavors become familiar and preferred. Infants can detect flavor changes in human milk resulting from parental lifestyle choices, including recreational drug use, and early experiences with the sensory properties of these recreational drugs impact subsequent behavioral responses. Interactions between the infant's own developing microbiome, that of the milk, and the multiple environmental factors that are drivers-both modifiable and nonmodifiable-in the microbial ecology of human milk are explored. Disruptions in gestation, especially preterm birth and fetal growth restriction or excess, impact the milk composition and lactation processes such as the timing of secretory activation, adequacy of milk volume and milk removal, and duration of lactation. Research gaps are identified in each of these areas. To assure a sustained and robust breastfeeding ecology, these myriad infant inputs must be systematically considered.

Association of Body Mass Index and Waist Circumference With Imaging Metrics of Brain Integrity and Functional Connectivity in Children Aged 9 to 10 Years in the US, 2016-2018.

Importance: Aside from widely known cardiovascular implications, higher weight in children may have negative associations with brain microstructure and neurodevelopment. Objective: To evaluate the association of body mass index (BMI) and waist circumference with imaging metrics that approximate brain health. Design, Setting, and Participants: This cross-sectional study used data from the Adolescent Brain Cognitive Development (ABCD) study to examine the association of BMI and waist circumference with multimodal neuroimaging metrics of brain health in cross-sectional and longitudinal analyses over 2 years. From 2016 to 2018, the multicenter ABCD study recruited more than 11 000 demographically representative children aged 9 to 10 years in the US. Children without any history of neurodevelopmental or psychiatric disorders were included in this study, and a subsample of children who completed 2-year follow-up (34%) was included for longitudinal analysis. Exposures: Children's weight, height, waist circumference, age, sex, race and ethnicity, socioeconomic status, handedness, puberty status, and magnetic resonance imaging scanner device were retrieved and included in the analysis. Main Outcomes and Measures: Association of preadolescents' BMI z scores and waist circumference with neuroimaging indicators of brain health: cortical morphometry, resting-state functional connectivity, and white matter microstructure and cytostructure. Results: A total of 4576 children (2208 [48.3%] female) at a mean (SD) age of 10.0 years (7.6 months) were included in the baseline cross-sectional analysis. There were 609 (13.3%) Black, 925 (20.2%) Hispanic, and 2565 (56.1%) White participants. Of those, 1567 had complete 2-year clinical and imaging information at a mean (SD) age of 12.0 years (7.7 months). In cross-sectional analyses at both time points, higher BMI and waist circumference were associated with lower microstructural integrity and neurite density, most pronounced in the corpus callosum (fractional anisotropy for BMI and waist circumference at baseline and second year: P < .001; neurite density for BMI at baseline: P < .001; neurite density for waist circumference at baseline: P = .09; neurite density for BMI at second year: P = .002; neurite density for waist circumference at second year: P = .05), reduced functional connectivity in reward- and control-related networks (eg, within the salience network for BMI and waist circumference at baseline and second year: P < .002), and thinner brain cortex (eg, for the right rostral middle frontal for BMI and waist circumference at baseline and second year: P < .001). In longitudinal analysis, higher baseline BMI was most strongly associated with decelerated interval development of the prefrontal cortex (left rostral middle frontal: P = .003) and microstructure and cytostructure of the corpus callosum (fractional anisotropy: P = .01; neurite density: P = .02). Conclusions and Relevance: In this cross-sectional study, higher BMI and waist circumference among children aged 9 to 10 years were associated with imaging metrics of poorer brain structure and connectivity as well as hindered interval development. Future follow-up data from the ABCD study can reveal long-term neurocognitive implications of excess childhood weight. Imaging metrics that had the strongest association with BMI and waist circumference in this population-level analysis may serve as target biomarkers of brain integrity in future treatment trials of childhood obesity.

No such thing as a free lunch: The direct marginal costs of breastfeeding.

Understanding costs associated with breastfeeding is critical to developing maximally effective policy to support breastfeeding by addressing financial barriers. Breastfeeding is not without cost; direct costs include those of equipment, modified nutritional intake, and time (opportunity cost). Breastfeeding need not require more equipment than formula feeding, though maternal equipment use varies by maternal preference. Meeting increased nutritional demands requires increased spending on food and potentially dietary supplementation, the marginal cost of which depends on a mother's baseline diet. The opportunity cost of the three to four hours per day breastfeeding demands may be prohibitively high, particularly to low-income workers. These costs are relatively highest for low-income individuals, a group disproportionately comprising racial and ethnic minorities, and who demonstrate lower rates of breastfeeding than their white and higher-income peers. Acknowledging and addressing these costs and their regressive nature represents a critical component of effective breastfeeding policy and promotion.

Self-Efficacy and Outcomes in Women with Diabetes: A Prospective Comparative Study.

Background: Breastfeeding is especially beneficial to women with diabetes and their infants, yet diabetic mothers frequently experience less favorable breastfeeding outcomes. Objectives: To identify facilitators and barriers to breastfeeding for women with diabetes by comparing cognitive and social factors, health and hospital-related factors, and breastfeeding outcomes between women with and without diabetes. Design/Methods: Women with any type of diabetes (n = 28) and without diabetes (n = 29) were recruited during pregnancy. Data were collected from the electronic medical record and maternal surveys at 24-37 weeks' gestation, birth hospitalization, and 4 weeks' postbirth. We compared differences in mother's regard for breastfeeding, breastfeeding intention, and birth hospital experience by diabetes status, and estimated odds ratios for exclusive breastfeeding (EBF) and unmet intention to breastfeed. Results: Women with and without diabetes had similar breastfeeding intentions, attitudes, and self-efficacy. Women with diabetes were less likely to EBF, and more likely to have unmet intentions to EBF at hospital discharge, compared to women without diabetes. At 4 weeks' postpartum, there was no difference in breastfeeding by diabetes status, although EBF at hospital discharge was strongly associated with EBF at 4 weeks. Infant neonatal intensive care unit (NICU) admission and hypoglycemia were significantly associated with diabetes status, reduced EBF rates, and unmet breastfeeding intentions. Conclusions: Despite having a strong intent to breastfeed, women with diabetes experienced less favorable early breastfeeding outcomes and were less likely to meet their own breastfeeding goals. These differences may be driven by neonatal complications, such as infant hypoglycemia and NICU admissions, rather than maternal cognitive and social factors.

Pediatricians' Reports of Interaction with Infant Formula Companies.

Introduction: Seventy percent of countries follow the World Health Organization International Code of Marketing Breast Milk Substitutes that prohibits infant formula companies (IFC) from providing free products to health care facilities, providing gifts to health care staff, or sponsoring meetings. The United States rejects this code, which may impact breastfeeding rates in certain areas. Objective: We aimed at gathering exploratory data about interactions between IFC and pediatricians. Methods: We distributed an electronic survey to U.S. pediatricians asking about practice demographics, interactions with IFC, and breastfeeding practices. Using the zip code of the practice, we obtained additional information from the 2018 American Communities Survey, including median income, percent of mothers who had graduated college, percent of mothers working, and racial and ethnic identity. We compared demographic data for those pediatricians who had a formula company representative visit versus not and those who had a sponsored meal versus not. Results: Of 200 participants, the majority reported a formula company representative visit to their clinic (85.5%) and receiving free formula samples (90%). Representatives were more likely to visit areas with higher-income patients (median = $100K versus $60K, p < 0.001). They tended to visit and sponsor meals for pediatricians at private practices and in suburban areas. Most of the reported conferences attended (64%) were formula company-sponsored. Conclusion: Interactions between IFC and pediatricians are prevalent and occur in many forms. Future studies may reveal whether these interactions influence the advice of pediatricians or the behavior of mothers who had planned to exclusively breastfeed.

A 1-Tesla MRI system for dedicated brain imaging in the neonatal intensive care unit.

Objective: To assess the feasibility of a point-of-care 1-Tesla MRI for identification of intracranial pathologies within neonatal intensive care units (NICUs). Methods: Clinical findings and point-of-care 1-Tesla MRI imaging findings of NICU patients (1/2021 to 6/2022) were evaluated and compared with other imaging modalities when available. Results: A total of 60 infants had point-of-care 1-Tesla MRI; one scan was incompletely terminated due to motion. The average gestational age at scan time was 38.5 ± 2.3 weeks. Transcranial ultrasound (n = 46), 3-Tesla MRI (n = 3), or both (n = 4) were available for comparison in 53 (88%) infants. The most common indications for point-of-care 1-Tesla MRI were term corrected age scan for extremely preterm neonates (born at greater than 28 weeks gestation age, 42%), intraventricular hemorrhage (IVH) follow-up (33%), and suspected hypoxic injury (18%). The point-of-care 1-Tesla scan could identify ischemic lesions in two infants with suspected hypoxic injury, confirmed by follow-up 3-Tesla MRI. Using 3-Tesla MRI, two lesions were identified that were not visualized on point-of-care 1-Tesla scan: (1) punctate parenchymal injury versus microhemorrhage; and (2) small layering IVH in an incomplete point-of-care 1-Tesla MRI with only DWI/ADC series, but detectable on the follow-up 3-Tesla ADC series. However, point-of-care 1-Tesla MRI could identify parenchymal microhemorrhages, which were not visualized on ultrasound. Conclusion: Although limited by field strength, pulse sequences, and patient weight (4.5 kg)/head circumference (38 cm) restrictions, the Embrace® point-of-care 1-Tesla MRI can identify clinically relevant intracranial pathologies in infants within a NICU setting.

Dilemmas in initiation of very preterm infant enteral feeds-when, what, how?

With limited clinical evidence available to guide common nutritional decisions, significant variation exists in approaches to enteral feeding for very preterm infants, specifically when feedings are initiated, what is fed, and the method used for feedings. Preclinical studies have highlighted the benefits associated with avoiding nil per os and providing early-stage mother's own milk or colostrum. However, these recommended approaches are often mutually exclusive due to the delays in lactation associated with very preterm delivery, resulting in uncertainty regarding which approach should be prioritized. Few studies have evaluated feeding frequency in preterm infants, with limited generalizability to extremely preterm infants. Therefore, even evidence-based approaches to very preterm infant feed initiation can differ. Future research is needed to identify optimal strategies for enteral nutrition in very preterm infants, but, until then, evidence-informed approaches may vary depending on each neonatal intensive care unit's assessment of risk and benefit.

A review and guide to nutritional care of the infant with established bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) remains the most common long-term morbidity of premature birth, and the incidence of BPD is not declining despite medical advancements. Infants with BPD are at high risk for postnatal growth failure and are often treated with therapies that suppress growth. Additionally, these infants may display excess weight gain relative to linear growth. Optimal growth and nutrition are needed to promote lung growth and repair, improve long-term pulmonary function, and improve neurodevelopmental outcomes. Linear growth in particular has been associated with favorable outcomes yet can be difficult to achieve in these patients. While there has been a significant clinical and research focus regarding BPD prevention and early preterm nutrition, there is a lack of literature regarding nutritional care of the infant with established BPD. There is even less information regarding how nutritional needs change as BPD evolves from an acute to chronic disease. This article reviews the current literature regarding nutritional challenges, enteral nutrition management, and monitoring for patients with established BPD. Additionally, this article provides a practical framework for interdisciplinary nutritional care based on our clinical experience at the Comprehensive Center for Bronchopulmonary Dysplasia.

Brain injury patterns in hypoxic ischemic encephalopathy of term neonates.

BACKGROUND AND PURPOSE: Topographic patterns of brain injury in neonates can help with differentiation and prognostic categorization of hypoxic ischemic encephalopathy (HIE). In this study, we quantitatively and objectively characterized the location of hypoxic ischemic lesions in term neonates with varying severity of HIE. METHODS: We analyzed term neonates (born ≥37 postmenstrual gestational weeks) with MRI diffusion-weighted imaging (DWI) and diagnoses of HIE. Neonates' HIE was categorized into mild, moderate, and severe. The hypoxic ischemic lesions were segmented on DWI series with attention to T1- and T2-weighted images and then co-registered onto standard brain space to generate summation maps for each severity category. Applying voxel-wise general linear models, we also identified cerebral regions more likely to infarct with increasing severity of HIE, after correction for lesion volume and time-to-scan as covariates. RESULTS: We included 33 neonates: 20 with mild, eight with moderate, and five with severe HIE. Infarct volumes (p = .00052) and Appearance, Pulse, Grimace, Activity, and Respiration scores at 1 minute (p = .032) differed between HIE severity categories. Hypoxic ischemic lesions in neonates with mild and moderate HIE were predominant in subcortical and deep white matter along the border zones of arterial supply territories, while severe HIE also involved basal ganglia, hippocampus, and thalamus. In voxel-wise analysis, higher severity of HIE was associated with the presence of lesions in hippocampus, thalamus, and lentiform nucleus. CONCLUSIONS: In term neonates, mild/moderate HIE is associated with infarctions of arterial territory watershed zones, whereas severe HIE distinctively involves basal ganglia, thalami, and hippocampi.

Preterm infant nutrition: considerations for infants at risk of refeeding syndrome.

Refeeding syndrome (RS) in preterm infants is a scenario of fetal malnutrition, primarily resulting from placental insufficiency, followed by a postnatal physiologic adaptation and response to an imbalance of nutrients provided parenterally. Growth restriction and small gestational age status are common findings in infants at risk of developing RS. Adverse clinical outcomes associated with RS may be severe and life-threatening. The biochemical abnormalities that occur in RS may be mitigated through careful monitoring and adaptation of the clinical management of parenteral and enteral nutrition. This perspective reviews the physiology and metabolism in infants with RS and provides suggested approaches to their clinical monitoring and nutritional management.