Zinc and copper requirements in preterm infants: an examination of the current literature

The Influence of Early Nutrition on Neurodevelopmental Outcomes in Preterm Infants

Premature infants, given their limited reserves, heightened energy requirements, and susceptibility to nutritional deficits, require specialized care.

AIM

To examine the complex interplay between nutrition and neurodevelopment in premature infants, underscoring the critical need for tailored nutritional approaches to support optimal brain growth and function.

DATA SOURCES

PubMed and MeSH and keywords: preterm, early nutrition, macronutrients, micronutrients, human milk, human milk oligosaccharides, probiotics AND neurodevelopment or neurodevelopment outcomes. Recent articles were selected according to the authors' judgment of their relevance. Specific nutrients, including macro (amino acids, glucose, and lipids) and micronutrients, play an important role in promoting neurodevelopment. Early and aggressive nutrition has shown promise, as has recognizing glucose as the primary energy source for the developing brain. Long-chain polyunsaturated fatty acids, such as DHA, contribute to brain maturation, while the benefits of human milk, human milk oligosaccharides, and probiotics on neurodevelopment via the gut-brain axis are explored. This intricate interplay between the gut microbiota and the central nervous system highlights human milk oligosaccharides' role in early brain maturation.

CONCLUSIONS

Individualized nutritional approaches and comprehensive nutrient strategies are paramount to enhancing neurodevelopment in premature infants, underscoring human milk's potential as the gold standard of nutrition for preterm infants.

Effects of early introduction of solid foods on nutrient intake in preterm infants during their 1st year of life: a secondary outcome analysis of a prospective, randomized intervention study

Very low birth weight (VLBW) infants have higher nutritional needs even after hospital discharge. However, data concerning current nutrient intakes at different time points after the introduction of solid foods and whether dietary reference values are being met are scarce. To adress this issue, this secondary analysis of a prospective, two-arm interventional study in 177 VLBW infants 21 investigates dietary intake comparing early and late (early: 10-12 weeks corrected for gestational age, late: 16-18 weeks corrected for gestational age) introduction of standardized complementary food during the first year of life. Nutritional intake was assessed using self-reported monthly 3-day dietary records from 3 until 12 months, corrected for gestational age. The time point of the introduction of solid foods did not influence nutrient intake, but the early introduction of solids tended toward a higher proportional intake of protein and carbohydrates and a lower intake of fat as a percentage of total energy) during the 1st year of life, corrected for gestational age. The results of this study indicate that this standardized feeding concept was sufficient for zinc, calcium, and phosphorus intake. However, dietary iron and vitamin D intakes did not meet the recommendations. Thus, prolonged iron supplementation should be considered beyond the introduction of meat and vitamin D supplementation at least until 12 months, corrected for gestational age.

Trial registration number

ClinicalTrials.gov: NCT01809548.

The Trace Element Concentrations and Oxidative Stress Parameters in Afterbirths from Women with Multiple Pregnancies

The aim of this study was to evaluate the intensity of oxidative stress by measuring the concentrations of lipid peroxidation products (LPO) in fetal membrane, umbilical cord, and placenta samples obtained from women with multiple pregnancies. Additionally, the effectiveness of protection against oxidative stress was assessed by measuring the activity of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR). Due to the role of iron (Fe), copper (Cu), and zinc (Zn) as cofactors for antioxidant enzymes, the concentrations of these elements were also analyzed in the studied afterbirths. The obtained data were compared with newborn parameters, selected environmental factors, and the health status of women during pregnancy to determine the relationship between oxidative stress and the health of women and their offspring during pregnancy. The study involved women (n = 22) with multiple pregnancies and their newborns (n = 45). The Fe, Zn, and Cu levels in the placenta, umbilical cord, and fetal membrane were determined using inductively coupled plasma atomic emission spectroscopy (ICP-OES) using an ICAP 7400 Duo system. Commercial assays were used to determine SOD, GPx, GR, CAT, and LPO activity levels. The determinations were made spectrophotometrically. The present study also investigated the relationships between trace element concentrations in fetal membrane, placenta, and umbilical cord samples and various maternal and infant parameters in women. Notably, a strong positive correlation was observed between Cu and Zn concentrations in the fetal membrane (p = 0.66) and between Zn and Fe concentrations in the placenta (p = 0.61). The fetal membrane Zn concentration exhibited a negative correlation with shoulder width (p = -0.35), while the placenta Cu concentration was positively correlated with placenta weight (p = 0.46) and shoulder width (p = 0.36). The umbilical cord Cu level was positively correlated with head circumference (p = 0.36) and birth weight (p = 0.35), while the placenta Fe concentration was positively correlated with placenta weight (p = 0.33). Furthermore, correlations were determined between the parameters of antioxidative stress (GPx, GR, CAT, SOD) and oxidative stress (LPO) and the parameters of infants and maternal characteristics. A negative correlation was observed between Fe and LPO product concentrations in the fetal membrane (p = -0.50) and placenta (p = -0.58), while the Cu concentration positively correlated with SOD activity in the umbilical cord (p = 0.55). Given that multiple pregnancies are associated with various complications, such as preterm birth, gestational hypertension, gestational diabetes, and placental and umbilical cord abnormalities, research in this area is crucial for preventing obstetric failures. Our results could serve as comparative data for future studies. However, we advise caution when interpreting our results, despite achieving statistical significance.

Association of serum and erythrocyte zinc levels with breastfeeding and complementary feeding in preterm and term infants

Zinc is an important nutrient involved in cell division, physical growth, and immune system function. Most studies evaluating the nutritional status related to zinc and prematurity were conducted with hospitalized preterm infants. These studies show controversial results regarding the prevalence of deficiency, clinical implications, and the effect of zinc supplementation on mortality, infectious diseases, and growth in these groups. This study aimed to compare serum and erythrocyte zinc levels in a group of preterm and full-term infants after 9 months of age, and related the zinc levels to dietary intake and anthropometric indicators in both groups. This cross-sectional study compared 43 preterm infants (24 to 33 weeks) aged 9-24 months to 47 full-term healthy infants. Outcome measures: anthropometric indicators and dietary intake. Blood sample for serum and erythrocyte zinc levels (ICP-MS, Inductively Coupled Plasma Mass Spectrometry). There was no difference between the groups regarding the mean of serum and erythrocyte zinc. Variables associated with higher serum zinc levels were breastfeeding at evaluation (β = 20.11 µg/dL, 95% CI 9.62-30.60, p < 0.001) and the later introduction of solid foods (β = 6.6 µg/dL, 95% CI 5.3-11.4, p < 0.001). Breastfeeding was also associated with higher erythrocyte zinc levels. The zinc levels were adequate in both groups, there was no association with anthropometric indicators or dietary intake and were slightly influenced by breastfeeding and time of solid food introduction.

Effect of enteral zinc supplementation on growth and neurodevelopment of preterm infants: a systematic review and meta-analysis

OBJECTIVE

To evaluate effect of enteral zinc supplementation on growth and neurodevelopmental outcomes of preterm infants.

STUDY DESIGN

A systematic review and meta-analysis of randomized-controlled trials (RCTs) examining growth and neurodevelopmental outcomes after zinc supplementation in preterm infants.

RESULTS

Of eight RCTs involving 742 infants included, seven reported growth anthropometrics at 3-6 months corrected age (CA) and two reported neurodevelopmental outcomes at 6-12 months CA. Zinc supplementation was associated with increased weight z-score (weighted mean difference (WMD) = 0.50; 95% CI 0.23-0.76, heterogeneity I2 = 89.1%; P < 0.01), length z-score (WMD = 1.12; 95% CI 0.63-1.61, heterogeneity I2 = 96.0%; P < 0.01) and motor developmental score (WMD = 9.54; 95% CI 6.6-12.4 heterogeneity I2 = 0%; P = 0.52). There was no effect on head circumference and total developmental score. Evidence is "moderate" certainty for weight and length and "very low" certainty for neurodevelopment.

CONCLUSION

Zinc supplementation may enhance weight gain and linear growth in preterm infants. There is a lack of data about relationship between zinc supplementation and neurodevelopment.

Review of Preterm Human-Milk Nutrient Composition

BACKGROUND

The human milk-fed preterm infant is at risk for growth failure, micronutrient deficiencies, and neurocognitive delay. Although protective and better tolerated than formula, human milk alone cannot meet the high nutrient requirements of this population, and fortification is necessary. Clinicians use assumptions of preterm human-milk composition to determine the type and quantity of fortification.

OBJECTIVES

The objectives of this review were to identify evidence of macronutrient and micronutrient concentration in preterm human milk and to identify knowledge gaps regarding composition.

METHODS

PubMed and the Cumulative Index to Nursing and Allied Health Literature were used to identify original articles published between January 1950 and December 2019.

RESULTS

Twenty-seven articles were found containing original data on macronutrients and micronutrients. Most (67%) of the studies published after 2011 measured the macronutrients and included gestational ages from 28 to 36 weeks. Milk collection methods, experimental design, and analytical methods varied between studies. There are 15 countries represented in this review; all of the American studies (n = 7) were published from 1980 to 1984.

CONCLUSIONS

African American women, or women delivering before 28 weeks' gestation are not represented in the literature. Accurate and targeted human-milk fortification depends on comprehensive, complete, and representative human-milk nutrient data. We have aggregated all available preterm human-milk macronutrient and micronutrient data and reported trends associated with lactation stage and gestational age. This report can aid in the design of feeding plans that are appropriate for the gestational age of the preterm infant and the lactation stage of the breastmilk.

Copper and Zinc Content in Infant Milk Formulae Available on the Polish Market and Contribution to Dietary Intake

The inappropriate concentration of copper (Cu) and zinc (Zn) in formulae for infants can lead to abnormal micronutrient intake and adverse health outcomes. This study aimed to determine the concentration of Cu and Zn in different formulae and evaluate the Cu/Zn ratio. Besides, the daily intake (DI) of both micronutrients was estimated. Cu and Zn concentration in 103 formulae for infants, available in the Polish market, were assessed using atomic absorption spectrometry. The estimated DI was calculated from the average energy requirements for the 0-6 months aged infants. The microelement content of formulae was mostly in good agreement with that declared by the manufacturer (5-10% variations compared to the labeled values). The Cu/Zn ratio ranged from 1:8 to 1:25. The estimated DI of Cu was in the range of 0.14-1.11 mg/day. Six (6.7%) of the formulae did not meet the recommended range of Cu intake, especially during the first month of life and in the case of formulae for special medical purposes. The estimated DI of Zn varied from 2.27-11.25 mg/day. In most cases, the concentration of Cu and Zn in infant formulae was within the recommended range. It would be advisable to consider monitoring the DI of Cu and reconsider the Cu content in formulae for infants in proportion to its expected consumption.

Role of zinc in neonatal growth and brain growth: review and scoping review

This manuscript includes (1) a narrative review of Zinc as an essential nutrient for fetal and neonatal growth and brain growth and development and (2) a scoping review of studies assessing the effects of Zinc supplementation on survival, growth, brain growth, and neurodevelopment in neonates. Very preterm infants and small for gestational age infants are at risk for Zinc deficiency. Zinc deficiency can cause several complications including periorificial lesions, delayed wound healing, hair loss, diarrhea, immune deficiency, growth failure with stunting, and brain atrophy and dysfunction. Zinc is considered essential for oligodendrogenesis, neurogenesis, neuronal differentiation, white matter growth, and multiple biological and physiological roles in neurobiology. Data support the possibility that the critical period of Zinc delivery for brain growth in the mouse starts at 18 days of a 20-21-day pregnancy and extends during lactation and in human may start at 26 weeks of gestation and extend until at least 44 weeks of postmenstrual age. Studies are needed to better elucidate Zinc requirement in extremely low gestational age neonates to minimize morbidity, optimize growth, and brain growth, prevent periventricular leukomalacia and optimize neurodevelopment. IMPACT: Zinc is essential for growth and brain growth and development. In the USA, very preterm small for gestational age infants are at risk for Zinc deficiency. Data support the possibility that the critical period of Zinc delivery for brain growth in the mouse starts at 18 days of a 20-21-day pregnancy and extends during lactation and in human may start at 26 weeks' gestation and extend until at least 44 weeks of postmenstrual age. Several randomized trials of Zinc supplementation in neonates have shown improvement in growth when using high enough dose, for long duration in patients likely to or proven to have a Zinc deficiency. Studies are needed to better elucidate Zinc requirement in extremely low gestational age neonates to minimize morbidity, optimize growth and brain growth, prevent periventricular leukomalacia and optimize neurodevelopment.

Overview of Important Micronutrients Supplementation in Preterm Infants after Discharge: A Call for Consensus

Preterm infants have a lower level of nutrient body stores and immature body systems, resulting in a higher risk of malnutrition. Imbalanced complementary feeding could lead to further risk of nutritional deficits and excesses. However, evidence on their nutritional requirements following hospital discharge is limited. When planning complementary feeding, appropriate micronutrient intake should be considered for their critical role in supporting various body functions. This narrative review summarizes the need for iron, zinc, vitamin D, calcium, phosphate and long-chain polyunsaturated fatty acids (LCPUFAs) supplementation in preterm infants during complementary feeding. Regarding iron and vitamin D, the scientific community is reaching an agreement on supplementation in some categories of prematures. On the contrary, there is still not enough evidence to detail possible recommendations for LCPUFAs, zinc, calcium and phosphorus supplementation. However, these micronutrients are paramount for preterms' health: LCPUFAs can promote retinal and brain development while calcium and phosphorus supplementation is essential to prevent preterms' metabolic bone disease (MBD). Waiting for a consensus on these micronutrients, it is clear how the knowledge of the heterogeneity of the prematures population can help adjust the nutritional planning regarding the growth rate, comorbidities and comprehensive clinical history of the preterm infant.

Cord levels of zinc and copper in relation to maternal serum levels in different gestational ages

Background

A few published data on maternal and cord levels of zinc and copper with conflicting results were reported. We aimed to measure zinc and copper levels in the maternal blood and cord blood of newborns and correlate their levels with the gestational age and anthropometric measurements. This cross-sectional study included 75 full-term and preterm neonates and their mothers. These neonates were divided into 2 groups according to their gestational age. Serum levels of copper and zinc were estimated for the mothers of the studied neonates as well as their cord samples. This was done using atomic absorption spectrophotometry.

Results

The mean cord serum zinc in full term was 0.88 ± 0.18 μg/ml whereas in preterms was 0.73 ± 0.13 μg/ml. The mean cord copper in full term was 1.37 ± 0.26 μg/ml, whereas in preterms was 0.75 ± 0.28 μg/ml. Comparison between cord zinc and copper levels and maternal levels were statistically significant (p < 0.001). A significant positive correlation was found between zinc levels in neonates and their mothers (r 0.644; p < 0.000) and a similar positive correlation was found between copper levels in neonates and their mothers (r 0.625; p 0.000). A highly significant positive correlation was found between cord zinc and copper and anthropometric measurements.

Conclusion

The present work draws our attention to the significant correlation between trace elements in pregnant mothers and fetal development. Also, prematurity adversely influences zinc and copper levels in neonates.

Enteral zinc supplementation for prevention of morbidity and mortality in preterm neonates

BACKGROUND

Preterm and low birth weight infants are born with low stores in zinc, which is a vital trace element for growth, cell differentiation and immune function. Preterm infants are at risk of zinc deficiency during the postnatal period of rapid growth. Systematic reviews in the older paediatric population have previously shown that zinc supplementation potentially improves growth and positively influences the course of infectious diseases. In paediatric reviews, the effect of zinc supplementation was most pronounced in those with low nutritional status, which is why the intervention could also benefit preterm infants typically born with low zinc stores and decreased immunity.

OBJECTIVES

To determine whether enteral zinc supplementation, compared with placebo or no supplementation, affects important outcomes in preterm infants, including death, neurodevelopment, common morbidities and growth.

SEARCH METHODS

Our searches are up-to-date to 20 February 2020. For the first search, we used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 8), MEDLINE via PubMed (1966 to 29 September 2017), Embase (1980 to 29 September 2017), and CINAHL (1982 to 29 September 2017). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs. We ran an updated search from 1 January 2017 to 20 February 2020 in the following databases: CENTRAL via CRS Web, MEDLINE via Ovid, and CINAHL via EBSCOhost.

SELECTION CRITERIA

We included RCTs and quasi-RCTs that compared enteral zinc supplementation versus placebo or no supplementation in preterm infants (gestational age < 37 weeks), and low birth weight babies (birth weight < 2500 grams), at any time during their hospital admission after birth. We included zinc supplementation in any formulation, regimen, or dose administered via the enteral route. We excluded infants who underwent gastrointestinal (GI) surgery during their initial hospital stay, or had a GI malformation or another condition accompanied by abnormal losses of GI juices, which contain high levels of zinc (including, but not limited to, stomas, fistulas, and malabsorptive diarrhoea).

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal. Two review authors separately screened abstracts, evaluated trial quality and extracted data. We synthesised effect estimates using risk ratios (RR), risk differences (RD), and standardised mean differences (SMD). Our primary outcomes of interest were all-cause mortality and neurodevelopmental disability. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included five trials with a total of 482 preterm infants; there was one ongoing trial. The five included trials were generally small, but of good methodological quality. Enteral zinc supplementation compared to no zinc supplementation Enteral zinc supplementation started in hospitalised preterm infants may decrease all-cause mortality (between start of intervention and end of follow-up period) (RR 0.55, 95% CI 0.31 to 0.97; 3 studies, 345 infants; low-certainty evidence). No data were available on long-term neurodevelopmental outcomes at 18 to 24 months of (post-term) age. Enteral zinc supplementation may have little or no effect on common morbidities such as bronchopulmonary dysplasia (RR 0.66, 95% CI 0.31 to 1.40, 1 study, 193 infants; low-certainty evidence), retinopathy of prematurity (RR 0.14, 95% CI 0.01 to 2.70, 1 study, 193 infants; low-certainty evidence), bacterial sepsis (RR 1.11, 95% CI 0.60 to 2.04, 2 studies, 293 infants; moderate-certainty evidence), or necrotising enterocolitis (RR 0.08, 95% CI 0.00 to 1.33, 1 study, 193 infants; low-certainty evidence). The intervention probably improves weight gain (SMD 0.46, 95% CI 0.28 to 0.64; 5 studies, 481 infants; moderate-certainty evidence); and may slightly improve linear growth (SMD 0.75, 95% CI 0.36 to 1.14, 3 studies, 289 infants; low-certainty evidence), but may have little or no effect on head growth (SMD 0.21, 95% CI -0.02 to 0.44, 3 studies, 289 infants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Enteral supplementation of zinc in preterm infants compared to no supplementation or placebo may moderately decrease mortality and probably improve short-term weight gain and linear growth, but may have little or no effect on common morbidities of prematurity. There are no data to assess the effect of zinc supplementation on long-term neurodevelopment.

Zinc deficiency limiting head growth to discharge in extremely low gestational age infants with insufficient linear growth: a cohort study

OBJECTIVE

To assess the relationship of size for age with zinc deficiency in extremely low gestational age (GA) infants (23-28 weeks, ELGANs) who had insufficient linear growth despite optimizing other nutrients and to analyze changes in fronto-occipital circumference (FOC), weight and length with zinc supplementation.

STUDY DESIGN

Retrospective cohort study.

RESULTS

Among 302 ELGANs, a serum zinc concentration was obtained in 52 with insufficient linear growth (17%). Zinc deficiency (serum concentration <0.74 mcg/ml) was diagnosed in 8 of 24 (33%) small for GA (SGA) compared to 35 of 278 (13%) non-SGA infants (P = 0.01). Zinc supplementation for >2 weeks improved FOC growth to discharge or 50 weeks postmenstrual age in infants with Zn deficiency. However, neither linear growth nor weight gain improved with Zn supplementation.

CONCLUSION

Zinc deficiency was diagnosed in 14% ELGANs in this cohort. Zinc supplementation for >2 weeks improved FOC growth but not linear growth or weight gain.

The Role of Zinc in Copper Homeostasis of Aspergillus fumigatus

Copper is an essential metal ion that performs many physiological functions in living organisms. Deletion of Afmac1, which is a copper-responsive transcriptional activator in A. fumigatus, results in a growth defect on aspergillus minimal medium (AMM). Interestingly, we found that zinc starvation suppressed the growth defect of the Δafmac1 strain on AMM. In addition, the growth defect of the Δafmac1 strain was recovered by copper supplementation or introduction of the CtrC gene into the Δafmac1 strain. However, chelation of copper by addition of BCS to AMM failed to recover the growth defect of the Δafmac1 strain. Through Northern blot analysis, we found that zinc starvation upregulated CtrC and CtrA2, which encode membrane copper transporters. Interestingly, we found that the conserved ZafA binding motif 5'-CAA(G)GGT-3' was present in the upstream region of CtrC and CtrA2 and that mutation of the binding motif led to failure of ZafA binding to the upstream region of CtrC and upregulation of CtrC expression under zinc starvation. Furthermore, the binding activity of ZafA to the upstream region of CtrC was inversely proportional to the zinc concentration, and copper inhibited the binding of ZafA to the upstream region of CtrC under a low zinc concentration. Taken together, these results suggest that ZafA upregulates copper metabolism by binding to the ZafA binding motif in the CtrC promoter region under low zinc concentration, thus regulating copper homeostasis. Furthermore, we found that copper and zinc interact in cells to maintain metal homeostasis.

NICU Diet, Physical Growth and Nutrient Accretion, and Preterm Infant Brain Development

Half of very preterm infants experience neurodevelopmental impairments after NICU discharge. These adverse outcomes result in part from abnormal brain development and injury that occur during the NICU hospitalization. Although many factors influence infant brain development, nutritional determinants are of particular interest because they are highly modifiable within clinical care. Physical growth of preterm infants in the NICU continues to lag behind the reference fetus, suggesting reduced nutrient accretion during a critical period for brain development. Nutrient accretion is driven by intake of specific nutrients such as macro- and micronutrients as well as non-nutritional factors such as systemic inflammation. Most often, anthropometric indicators, such as weight, length, and head circumference, are used as proxies for nutrient accretion. A limitation of weight is that it does not differentiate the healthy growth of specific organs and tissues from excess fat accumulation. Body length provides information about skeletal growth, and linear growth stunting predicts neurodevelopmental impairment. Head circumference is only a crude proxy for brain size. More recently, application of new technologies such as air displacement plethysmography and magnetic resonance imaging has allowed the direct estimation of lean tissue accretion and brain growth in the NICU. These newer techniques can facilitate research to improve our understanding of the links among the NICU diet, inflammation, physical growth, and brain development. These new measures may also be relevant within clinical care to identify infants who may benefit from specific interventions to enhance nutrient accretion and brain development.

Dysmaturation of Premature Brain: Importance, Cellular Mechanisms, and Potential Interventions

Prematurity, especially preterm birth (less than 32 weeks' gestation), is common and associated with high rates of both survival and neurodevelopmental disability, especially apparent in cognitive spheres. The neuropathological substrate of this disability is now recognized to be related to a variety of dysmaturational disturbances of the brain. These disturbances follow initial brain injury, particularly cerebral white matter injury, and involve many of the extraordinary array of developmental events active in cerebral white and gray matter structures during the premature period. This review delineates these developmental events and the dysmaturational disturbances that occur in premature infants. The cellular mechanisms involved in the genesis of the dysmaturation are emphasized, with particular focus on the preoligodendrocyte. A central role for the diffusely distributed activated microglia and reactive astrocytes in the dysmaturation is now apparent. As these dysmaturational cellular mechanisms appear to occur over a relatively long time window, interventions to prevent or ameliorate the dysmaturation, that is, neurorestorative interventions, seem possible. Such interventions include pharmacologic agents, especially erythropoietin, and particular attention has also been paid to such nutritional factors as quality and source of milk, breastfeeding, polyunsaturated fatty acids, iron, and zinc. Recent studies also suggest a potent role for interventions directed at various experiential factors in the neonatal period and infancy, i.e., provision of optimal auditory and visual exposures, minimization of pain and stress, and a variety of other means of environmental behavioral enrichment, in enhancing brain development.

Evaluation of Key Factors Impacting Feeding Safety in the Neonatal Intensive Care Unit: A Systematic Review

BACKGROUND

Individualized feeding care plans and safe handling of milk (human or formula) are critical in promoting growth, immune function, and neurodevelopment in the preterm infant. Feeding errors and disruptions or limitations to feeding processes in the neonatal intensive care unit (NICU) are associated with negative safety events. Feeding errors include contamination of milk and delivery of incorrect or expired milk and may result in adverse gastrointestinal illnesses.

PURPOSE

The purpose of this review was to evaluate the effect(s) of centralized milk preparation, use of trained technicians, use of bar code-scanning software, and collaboration between registered dietitians and registered nurses on feeding safety in the NICU.

METHODS/SEARCH STRATEGY

A systematic review of the literature was completed, and 12 articles were selected as relevant to search criteria. Study quality was evaluated using the Downs and Black scoring tool.

FINDINGS/RESULTS

An evaluation of human studies indicated that the use of centralized milk preparation, trained technicians, bar code-scanning software, and possible registered dietitian involvement decreased feeding-associated error in the NICU.

IMPLICATIONS FOR PRACTICE

A state-of-the-art NICU includes a centralized milk preparation area staffed by trained technicians, care supported by bar code-scanning software, and utilization of a registered dietitian to improve patient safety. These resources will provide nurses more time to focus on nursing-specific neonatal care.

IMPLICATIONS FOR RESEARCH

Further research is needed to evaluate the impact of factors related to feeding safety in the NICU as well as potential financial benefits of these quality improvement opportunities.

Turkish Neonatal Society guideline on enteral feeding of the preterm infant

Early initiation of enteral feeding with the own mother's milk and prevention of postnatal growth failure is the target of nutrition in preterm infants. Together with total parenteral nutrition, mouth care and minimal enteral nutrition is started with colostrum in the very early hours of life in small preterm infants. Expressed mother's milk is given via a gastric tube and gradually increased in accordance with the gestational age/birth weight and the risk factors. For infants born heavier than 1 000 grams, the aim is to reach total enteral feeding at the end of first week, and at the end of the second week for infants weighing less than 1000 grams. Supporting mothers in milk expression and kangaroo mother care, promoting non-nutritive feeding, appropriate fortification of mother' milk, and initiating and advancing breastfeeding as soon as the infant is ready are all crucial. Donor mother milk, and as a second choice, preterm formula is advised if the mother's milk is not available. Individualized post-discharge nutrition decisions can be taken in accordance with the actual growth at the time of discharge. The goal is optimal neurodevelopmental achievement together with the prevention of long-term metabolic problems. Late preterm infants, which constitute the majority of preterm infants, also need close nutritional attention and follow-up.

Association of zinc and copper with clinical parameters in the preterm newborn

BACKGROUND

Given that preterm infants are born at a time of rapid fetal growth, they are at risk of deficiency of essential nutrients for brain development, including zinc (Zn) and copper (Cu). This study evaluate the relationship between serum Cu or Zn, gestational age (GA) and anthropometric parameters at birth in preterm infants.

METHODS

This was a retrospective study of infants <35 weeks' GA from January 2010 to August 2012. We collected the data from medical records of 59 preterm infants at birth with regard to GA, anthropometric parameters, and serum Cu and Zn levels. Correlation of Cu, Zn, and GA with anthropometric parameters at birth was then done.

RESULTS

Zn was inversely correlated with GA, bodyweight (BW), body length (BL), and head circumference (HC), and Cu was inversely correlated with the standard deviation (SD) score for BW, BL, and HC. On stepwise multiple regression analysis, GA was a significant independent predictor of Zn level, and HC SD score was a significant independent predictor of Cu level.

CONCLUSIONS

Prematurity influences Zn, and intrauterine head growth restriction influences Cu at birth in preterm infants. Further research is needed to evaluate the relationship between intrauterine growth restriction and brain Cu metabolism.

Serum copper concentrations in hospitalized newborns

BACKGROUND

Low serum Cu and ceruloplasmin (Cp) concentrations in newborns can be the first indication of a severe Cu deficient intake or, alternatively, of genetic diseases affecting Cu metabolism. However, Cu and Cp concentrations can also be influenced by other variables that render their quantitative results difficult to interpret. Therefore, it is necessary to identify these variables and stratify Cu and Cp concentrations according to these altering factors.

METHODS

Serum Cu and Cp concentrations for 564 hospitalized newborns (0-12days of life) are stratified according to their age, prematurity (birth weight or gestational age), type of feeding and inflammatory state (assessed by the serum high sensitivity C-reactive protein (hs-CRP) level) to identify potential correlations.

RESULTS

Serum Cu and Cp concentrations are influenced by all four variables analyzed, although inflammation is the most significant: the greater the hs-CRP concentration, the greater the serum Cu and Cp concentrations. Prematurity is also an important factor and preterm infants often show very low Cu and Cp concentrations. Age of life and type of feeding have in turn a more modest effect on these magnitudes, being slightly greater at 3-5days of age in breastfed newborns.

CONCLUSIONS

Inflammation and prematurity are the main variables affecting serum Cu and Cp concentrations in newborns. Therefore, hs-CRP should always be assayed in parallel to Cu status. When there is an inflammatory state proper interpretation of these concentrations can be challenging.

Zinc and infant nutrition

Zinc is essential for a wide variety of cellular processes in all cells. It is a critical dietary nutrient, particularly in the early stages of life. In the early neonatal period, adequate sources of zinc can be obtained from breast milk. In rare circumstances, the mammary gland produces zinc deficient milk that is potentially lethal for exclusively breast-fed infants. This can be overcome by zinc supplementation to the infant. Alterations to key zinc transporters provide insights into the mechanisms of cellular zinc homeostasis. The bioavailability of zinc in food depends on the presence of constituents that may complex zinc. In many countries, zinc deficiency is a major health issue due to poor nourishment. Young children are particularly affected. Zinc deficiency can impair immune function and contributes to the global burden of infectious diseases including diarrhoea, pneumonia and malaria. Furthermore, zinc deficiency may extend its influence across generations by inducing epigenetic effects that alter the expression of genes. This review discusses the significance of adequate zinc nutrition in infants, factors that influence zinc nutrition, the consequences of zinc deficiency, including its contribution to the global burden of disease, and addresses some of the knowledge gaps in zinc biology.

[Nutrition in the preterm hospitalized newborn. Recommendations of the Chilean Neonatology Branch, Chilean Pediatric Society]

Recommendations based on current publications are presented for postnatal preterm nutrition, depending on birth weight: less 1000g, between 1000 and 1500g, and above 1500g, as well for the development periods: adaptation, stabilisation, and growth. A review is also presented on the nutritional management of morbidities that affect or may affect nutrition, such as: osteopenia, bronchopulmonary dysplasia, patent ductus arteriosus, red cell transfusion, and short bowel syndrome.

Working group reports: evaluation of the evidence to support practice guidelines for nutritional care of preterm infants-the Pre-B Project

The "Evaluation of the Evidence to Support Practice Guidelines for the Nutritional Care of Preterm Infants: The Pre-B Project" is the first phase in a process to present the current state of knowledge and to support the development of evidence-informed guidance for the nutritional care of preterm and high-risk newborn infants. The future systematic reviews that will ultimately provide the underpinning for guideline development will be conducted by the Academy of Nutrition and Dietetics' Evidence Analysis Library (EAL). To accomplish the objectives of this first phase, the Pre-B Project organizers established 4 working groups (WGs) to address the following themes: 1) nutrient specifications for preterm infants, 2) clinical and practical issues in enteral feeding of preterm infants, 3) gastrointestinal and surgical issues, and 4) current standards of infant feeding. Each WG was asked to 1) develop a series of topics relevant to their respective themes, 2) identify questions for which there is sufficient evidence to support a systematic review process conducted by the EAL, and 3) develop a research agenda to address priority gaps in our understanding of the role of nutrition in health and development of preterm/neonatal intensive care unit infants. This article is a summary of the reports from the 4 Pre-B WGs.

A longitudinal study of human milk composition in the second year postpartum: implications for human milk banking

While the composition of human milk has been studied extensively in the first year of lactation, there is a paucity of data regarding human milk composition beyond one year postpartum. Policies vary at milk banks around the world regarding how long lactating women are eligible to donate their milk. The primary purpose of this study is to describe longitudinal changes in human milk composition in the second year postpartum to support the development of evidence based guidelines regarding how long lactating women can donate human milk to a milk bank. Nineteen lactating women in North Carolina provided monthly milk samples from 11 months to 17 months postpartum (N = 131), and two non-profit milk banks provided (N = 33) pooled, unpasteurized milk samples from 51 approved donors less than one year postpartum. There was a significant increase (P < 0.05) in the concentration of total protein, lactoferrin, lysozyme, Immunoglobulin A, oligosaccharides and sodium in longitudinal samples of mother's milk between 11 and 17 months postpartum, while zinc and calcium concentrations declined, and no changes were observed in lactose, fat, iron and potassium. Human milk in the second year postpartum contained significantly higher concentrations of total protein, lactoferrin, lysozyme and Immunoglobulin A, than milk bank samples, and significantly lower concentrations of zinc, calcium, iron and oligosaccharides. Accepting milk bank donations beyond one year postpartum is a potential strategy for increasing the supply of donor milk, but may require mineral fortification.

Zinc in Early Life: A Key Element in the Fetus and Preterm Neonate

Zinc is a key element for growth and development. In this narrative review, we focus on the role of dietary zinc in early life (including embryo, fetus and preterm neonate), analyzing consequences of zinc deficiency and adequacy of current recommendations on dietary zinc. We performed a systematic search of articles on the role of zinc in early life. We selected and analyzed 81 studies. Results of this analysis showed that preservation of zinc balance is of critical importance for the avoidance of possible consequences of low zinc levels on pre- and post-natal life. Insufficient quantities of zinc during embryogenesis may influence the final phenotype of all organs. Maternal zinc restriction during pregnancy influences fetal growth, while adequate zinc supplementation during pregnancy may result in a reduction of the risk of preterm birth. Preterm neonates are at particular risk to develop zinc deficiency due to a combination of different factors: (i) low body stores due to reduced time for placental transfer of zinc; (ii) increased endogenous losses; and (iii) marginal intake. Early diagnosis of zinc deficiency, through the measurement of serum zinc concentrations, may be essential to avoid severe prenatal and postnatal consequences in these patients. Typical clinical manifestations of zinc deficiency are growth impairment and dermatitis. Increasing data suggest that moderate zinc deficiency may have significant subclinical effects, increasing the risk of several complications typical of preterm neonates (i.e., necrotizing enterocolitis, chronic lung disease, and retinopathy), and that current recommended intakes should be revised to meet zinc requirements of extremely preterm neonates. Future studies evaluating the adequacy of current recommendations are advocated.

Review of trace mineral requirements for preterm infants: what are the current recommendations for clinical practice?

Inadequate nutrient stores at birth are an inevitable consequence of being born prematurely. Preterm infants also have high nutrient requirements, which increase with earlier gestational ages. As a result, early nutrition intervention is required to prevent further deficits that, if not corrected, can affect growth and long-term outcomes. Preterm infants often require several weeks of parenteral nutrition (PN) support, which includes trace mineral supplementation. Trace minerals are considered essential nutrients, unable to be synthesized in the human body. Deficiencies of trace minerals have been reported, yet evidence-based guidelines for assessment and supplementation have not been clearly defined. Food and Drug Administration-approved parenteral trace mineral intake guidelines are more than 30 years old. In an effort to more clearly define trace mineral supplementation and monitoring guidelines for preterm infants, a review of literature was performed with the purpose to (1) summarize trace mineral roles in preterm infants, (2) describe clinical signs of deficiency and toxicity, and (3) present intake recommendations and considerations for preterm infants based on current available literature. Review of literature was completed using PubMed and Cochrane databases to find relevant studies specific to trace mineral requirements for preterm infants, trace mineral supplementation of PN, human milk fortifiers, and preterm infant formulas. Review of literature supports that trace mineral depletion can lead to clinical compromise in preterm infants; therefore, suggesting that every effort be made to ensure adequate provision of trace minerals is given to preterm infants. Practical considerations for the clinical nutrition management of preterm infants were also identified in this review.