Workshop summary: nutrition of the extremely low birth weight infant

Bolus Feeding Via Gastric Versus Oral Routes in Very Preterm Neonates

BACKGROUND

We intend to investigate the association of bolus orogastric tube (BOG) and nipple bottle (N) feedings with postnatal growth in very premature neonates (VPN: gestational age between 28 and 33 weeks).

MATERIAL AND METHODS

The days of life (DOL) to achieve full combined oral and gastric enteral nutrition (FEN) and attain body weight (BW) of 2200 g (Wt22) and the length of hospitalization (LOH) were retrospectively associated with clinical and BOG and N feeding-related variables via multivariate regression analyses. Correlations were performed to ascertain the strength of associations.

RESULTS

In a cohort of 127 VPN, FEN demonstrated negative associations with gestational age (GA) and LOH and Wt22 with birth weight (BW). FEN showed positive associations with nil by mouth and intravenous fluid-nutrition days and with DOL to start and achieve full nipple feeding. LOH was associated with days on antibiotics and DOL to start and achieve full nipple feeding. Wt22 was associated with DOL to achieve full nipple feeding. The start day of BOG feeding had no independent associations and weak, highly significant positive correlations with Wt22, LOH, and FEN.

CONCLUSION

Bolus orogastric tube feeding has no independent implications for postnatal growth, duration of hospitalization, or chronological age to attain full enteral nutrition in VPN unless combined with nipple feeding to provide enteral nutrition. Oral bottle feeding accelerates postnatal catch-up growth and full enteral nutrition acquisition while reducing hospitalization duration. Initiating nipple feeding at 32 weeks of postmenstrual age may be safe in stable VPN. Antibiotic therapy increases hospitalization duration.

High Amino Acid Intake in Early Life Is Associated With Systolic but Not Diastolic Arterial Hypertension at 5 Years of Age in Children Born Very Preterm

BACKGROUND

The life course of individuals born very premature is a topic of increasing concern. The association between high early amino acid intake and later high blood pressure (HBP) in preterm neonates is debated.

METHODS AND RESULTS

In a national, prospective, population-based birth cohort, EPIPAGE-2 (Etude Epidémiologique sur Petits Ages Gestationnels), we assessed blood pressure at 5 years. Eligible infants were those born between 24 and 29 weeks of gestation. Infants were distributed in 2 groups of 717 infants matched on propensity score on whether or not they were exposed to high amino acid intake (>3.5 g/kg per day at day 7); 455 control term infants were also enrolled. A value ≥95th percentile of reference values for age and height defined systolic or diastolic HBP. Blood pressure at 5 years of age was assessed for 389 and 385 children in the exposed and nonexposed groups, respectively. Rates (in percent) of systolic and diastolic HBP were 18.0% (95% CI, 14.5%-22.2%), 13.3% (95% CI, 10.3%-17.0%), 8.5% (95% CI, 6.5%-11.1%), and 9.0% (95% CI, 6.6%-12.3%), 10.2% (95% CI, 7.5%-13.6%), and 5.4% (95% CI, 3.8%-7.6%) in exposed, nonexposed, and term-born groups, respectively. Exposure to high early amino acid intake and maximal serum creatinine (by 50 μmol/L) between day 3 and day 7 were 2 independent risk factors for systolic HBP (adjusted odds ratio [aOR], 1.60 [95% CI, 1.05-2.43] and aOR, 1.59 [95% CI, 1.12-2.26], respectively) but not for diastolic HBP (aOR, 0.84 [95% CI, 0.50-1.39] and aOR, 1.09 [95% CI, 0.71-1.67], respectively). After adjustment for 5-year weight Z score, the aOR between high early amino acid intake and systolic HBP was 1.50 [95% CI, 0.98-2.30].

CONCLUSIONS

These results suggest that mechanisms of childhood systolic HBP involve neonatal renal challenge by high amino acid intake or dysfunction.

A predictive model for preterm babies born < 30 weeks gestational age who will not attain full oral feedings

OBJECTIVE

Develop a model to predict gastrostomy tube (GT) for feeding at discharge in infants born < 30 weeks' (w) gestational age (GA).

STUDY DESIGN

A single-center retrospective study at academic NICU. Total of 391 (78 GT, 313 non-GT) infants < 30 w GA admitted in 2015-2018 split into test (15-16) and validation (17-18) cohorts. Classification and regression tree analysis was used to identify predictive factors for GT.

RESULTS

Several factors were associated with GT requirements. Four factors included in the model were postmenstrual age (PMA) at first oral feeding, birth GA, high-frequency ventilation exposure, necrotizing enterocolitis stage II/III. Area under the receiver operator characteristic curve was 0.944 in the test cohort, 0.815 in the validation cohort. Implementation plan based on the model was developed.

CONCLUSIONS

We developed a predictive model to risk-stratify infants born < 30 w GA for failing full oral feeding. We hope implementation at 38 w PMA will result in earlier placement of needed GT and discharge.

Association Between Early Amino Acid Intake and Full-Scale IQ at Age 5 Years Among Infants Born at Less Than 30 Weeks' Gestation

IMPORTANCE

An international expert committee recently revised its recommendations on amino acid intake for very preterm infants, suggesting that more than 3.50 g/kg/d should be administered only to preterm infants in clinical trials. However, the optimal amino acid intake during the first week after birth in these infants is unknown.

OBJECTIVE

To evaluate the association between early amino acid intake and cognitive outcomes at age 5 years.

DESIGN, SETTING, AND PARTICIPANTS

Using the EPIPAGE-2 (Epidemiologic Study on Small-for-Gestational-Age Children-Follow-up at Five and a Half Years) cohort, a nationwide prospective population-based cohort study conducted at 63 neonatal intensive care units in France, a propensity score-matched analysis was performed comparing infants born at less than 30 weeks' gestation who had high amino acid intake (3.51-4.50 g/kg/d) at 7 days after birth with infants who did not. Participants were recruited between April 1 and December 31, 2011, and followed up from September 1, 2016, to December 31, 2017. Full-scale IQ (FSIQ) was assessed at age 5 years. A confirmatory analysis used neonatal intensive care unit preference for high early amino acid intake as an instrumental variable to account for unmeasured confounding. Statistical analysis was performed from January 15 to May 15, 2021.

EXPOSURES

Amino acid intake at 7 days after birth.

MAIN OUTCOMES AND MEASURES

The primary outcome was an FSIQ score greater than -1 SD (ie, ≥93 points) at age 5 years. A complementary analysis was performed to explore the association between amino acid intake at day 7 as a continuous variable and FSIQ score at age 5 years. Data from cerebral magnetic resonance imaging at term were available for a subgroup of preterm infants who participated in the EPIRMEX (Cerebral Abnormalities Detected by MRI, Realized at the Age of Term and the Emergence of Executive Functions) ancillary study.

RESULTS

Among 1789 preterm infants (929 boys [51.9%]; mean [SD] gestational age, 27.17 [1.50] weeks) with data available to determine exposure to amino acid intake of 3.51 to 4.50 g/kg/d at 7 days after birth, 938 infants were exposed, and 851 infants were not; 717 infants from each group could be paired. The primary outcome was known in 396 of 646 exposed infants and 379 of 644 nonexposed infants who were alive at age 5 years and was observed more frequently among exposed vs nonexposed infants (243 infants [61.4%] vs 206 infants [54.4%], respectively; odds ratio [OR], 1.33 [95% CI, 1.00-1.71]; absolute risk increase in events [ie, the likelihood of having an FSIQ score >-1 SD at age 5 years] per 100 infants, 7.01 [95% CI, 0.06-13.87]; P = .048). In the matched cohort, correlation was found between amino acid intake per 1.00 g/kg/d at day 7 and FSIQ score at age 5 years (n = 775; β = 2.43 per 1-point increase in FSIQ; 95% CI, 0.27-4.59; P = .03), white matter area (n = 134; β = 144 per mm2; 95% CI, 3-285 per mm2; P = .045), anisotropy of the corpus callosum (n = 50; β = 0.018; 95% CI, 0.016-0.021; P < .001), left superior longitudinal fasciculus (n = 42; β = 0.018; 95% CI, 0.010-0.025; P < .001), and right superior longitudinal fasciculus (n = 42; β = 0.014 [95% CI, 0.005-0.024; P = .003) based on magnetic resonance imaging at term. Confirmatory and sensitivity analyses confirmed these results. For example, the adjusted OR for the association between the exposure and the primary outcome was 1.30 (95% CI, 1.16-1.46) using the instrumental variable approach among 978 participants in the overall cohort, and the adjusted OR was 1.35 (95% CI, 1.05-1.75) using multiple imputations among 1290 participants in the matched cohort.

CONCLUSIONS AND RELEVANCE

In this cohort study, high amino acid intake at 7 days after birth was associated with an increased likelihood of an FSIQ score greater than -1 SD at age 5 years. Well-designed randomized studies with long-term follow-up are needed to confirm the benefit of this nutritional approach.

Poor postnatal weight growth is a late finding after sepsis in very preterm infants

OBJECTIVE

To characterise the association between sepsis and postnatal weight growth when accounting for the degree of growth restriction present at birth.

DESIGN

Retrospective matched cohort study using data from the Postnatal Growth and Retinopathy of Prematurity study. Participants were born with birth weights of <1500 g or gestational ages of <32 weeks between 2006 and 2011 at 29 neonatal centres in the USA and Canada. Sepsis was defined as a culture-confirmed bacterial or fungal infection of the blood or cerebrospinal fluid before 36 weeks' postmenstrual age (PMA). Growth was assessed as the change in weight z-score between birth and 36 weeks' PMA.

RESULTS

Of 4785 eligible infants, 813 (17%) developed sepsis and 693 (85%) were matched 1:1 to controls. Sepsis was associated with a greater decline in weight z-score (mean difference -0.09, 95% CI -0.14 to -0.03). Postnatal weight growth failure (decline in weight z- score>1) was present in 237 (34%) infants with sepsis and 179 (26%) controls (adjusted OR 1.49, 95% CI 1.12 to 1.97). Longitudinal growth trajectories showed similar initial changes in weight z-scores between infants with and without sepsis. By 3 weeks after sepsis onset, there was a greater decline in weight z-scores relative to birth values in those with sepsis than without sepsis (delta z-score -0.89 vs -0.77; mean difference -0.12, 95% CI -0.18 to -0.05). This significant difference persisted until 36 weeks or discharge.

CONCLUSION

Infants with sepsis had similar early weight growth trajectories as infants without sepsis but developed significant deficits in weight that were not apparent until several weeks after the onset of sepsis.

The impact of donor breast milk on metabolic bone disease, postnatal growth, and neurodevelopmental outcomes at 18 months' corrected age

BACKGROUND

Preterm infants are at risk for metabolic bone disease (MBD). Analysis of donor breast milk (DBM) shows lower levels of macronutrients compared with mother's own milk (MOM). The purpose of this study was to investigate the prevalence of MBD, rate of postnatal growth, and long-term neurodevelopmental outcomes in infants fed predominantly MOM vs DBM.

METHODS

Retrospective observational study of infants born <1500g and <32 weeks at New York University Langone Health or Bellevue Hospital from January 2014 to January 2018. Infants were divided into two groups: those who received >70% of feeds with either MOM or DBM by 34 weeks' corrected age (CA). MBD was assessed using alkaline phosphatase (AlkPO4) levels and radiographic findings. Data was also collected on growth, feeding tolerance, and long-term neurodevelopmental outcomes.

RESULTS

A total of 210 infants were included (MOM =156 and DBM =54). The DBM group had higher AlkPO4 levels for the first 3 weeks of life (P < .01). Growth was similar between the groups, and both groups demonstrated catch-up growth after discharge. No difference was seen in feeding intolerance, incidence of necrotizing enterocolitis, or sepsis. The DBM group had lower cognitive (odds ratio [OR], 0.93 [0.88-0.98]; P < .01) and language (OR, 0.95 [0.90-0.99]; P < .01) scores at 18 months' CA.

CONCLUSION

Infants fed predominantly DBM had elevated AlkPO4 levels suggestive of MBD but did not develop osteopenia. Despite appropriate growth and comparable short-term outcomes, infants fed DBM had lower cognitive and language scores at 18 months' CA.

Comparison of the Finger Feeding Method Versus Syringe Feeding Method in Supporting Sucking Skills of Preterm Babies

Aim: The aim of this study is to compare the efficiency of a new method called "finger feeding" with a well-known technique called syringe feeding for improving sucking skills and accelerating transition to breastfeeding in preterm infants. Materials and Methods: Totally 70 babies were included in this prospective randomized controlled study. Finger feeding method was applied in Group 1 (n = 35) and syringe feeding method was applied in Group 2 (n = 35). The COMFORTneo scale (CnS), oxygen saturation, pulse, respiratory rate, body temperature, amount of breast milk taken, and vomiting data were recorded before and after both applications. Hospitalization period and time elapsed for complete transition from both methods to breastfeeding were also recorded. Results: There was no statistical difference for birth weights, mean gestational age, and vital signs recorded before and after feeding between two groups. Predicted comfort and distress scores of Group 1 determined by the CnS were significantly lower than those of Group 2. This means that babies in the finger feeding group had better comfort than the those in Group 2 (p = 0.000). Time passed for transition to breastfeeding was significantly shorter than that in Group 2 (19.4 ± 15.0 days versus 29.7 ± 10.2 days, p = 0.000). Group 1 had lower amount of food leakage while feeding and their average weight gain at the end of 10th day was significantly higher (322.1 ± 82.3 g versus 252 ± 108.4 g, p = 0.004). They also were discharged earlier than Group 2 (25.8 ± 17.4 days versus 35.9 ± 13.0 days, p = 0.001). Conclusion: Finger feeding method is an effective way for increasing sucking abilities, accelerating transition to breastfeeding, and shortens duration of hospitalization in preterm infants.

Factors in Early Feeding Practices That May Influence Growth and the Challenges that Arise in Growth Outcomes Research

Growth in preterm infants is associated with improved outcomes during both the initial hospitalization and long-term. A single center investigation evaluated preterm infant in-hospital growth trajectory and how it related to early nutritional practices as a way to identify areas for quality improvement. Infants born <34 weeks’ gestational age and with discharge at or prior to 40 weeks’ gestational age were included and were divided into quartiles based on their change in weight z-score through hospitalization. Early nutritional factors were compared between the lowest and highest growth quartiles. Although the highest growth quartile experienced less days of parenteral nutrition and higher enteral caloric density in the first week, as the data was analyzed, potential statistical pitfalls became apparent. Therefore, the aim of this study was to investigate selection bias and cohort effect related to both the inclusion criteria for this cohort as well as the inherent challenges in comparison of preterm infant growth trajectories by standard fetal growth charts.

Effect of fortifiers on the osmolality of preterm human milk

Background: The nutritional content of preterm human milk (HM) can be increased by adding human milk fortifier (HMF). Premature formula (PF) has been used as an alternative to HMF due to the high cost of HMF in some countries. However, the osmolality of HM after fortification remains a matter of concern. Aim: To evaluate the osmolality of fortified preterm HM. Methods: This was a cross-sectional study. HM was collected from 28 mothers of infants with a gestational age of <32 weeks or birthweight <1500 g. Expressed HM was divided into (i) pure HM; (ii) HM+PF to 24 kcal/oz; (iii) HM+PF to 28 kcal/oz; and (iv) HM+HMF to 24 kcal/oz + protein powder 0.5 g/100 ml. Results: Twenty-eight samples of preterm HM were analysed. The mean (SD) osmolality of baseline HM was 297.6 (9.7) mOsm/kg. Mean osmolality of preterm HM after fortification with PF to 24 and 28 kcal/oz was 357.2 (11.1) and 419.9 (18.8) mOsm/kg, respectively. The mean osmolality after fortification with HMF plus protein powder was 464.1 (18.8) mOsm/kg. Repeated-measures ANOVA was used to compare osmolality between pure HM and HM fortified with different fortifiers. All pairwise comparisons by the Bonferroni method were statistically significant (p < 0.001). Conclusions: The osmolality of preterm HM fortified with PF up to 28 kcal/oz does not exceed the American Academy of Paediatrics recommendation of 450 mOsm/kg. The addition of extra protein to preterm HM fortified with commercial HMF must be cautiously considered due to the risk of excessively high osmolality.

Postnatal Growth Restriction Is Reduced If Birth Weight Is Used for Nutritional Calculations in ELBW Infants

Since fluid and nutrition needs and delivery in ELBW infants are calculated based on their body weights, there could be a measurable difference in fluid, nutrition, and protein intake calculations based on birth weight (BW) or current weight of the infant, especially in the first two weeks of life. Theoretically, the use of current daily weight (CW) for calculations may result in decreased fluid, nutrition, and protein delivery as well as a cumulative protein deficit (cPD) over the first two weeks of life until the infant regains birth weight. However, there have been no clinical studies comparing the clinical and nutritional impact of these two strategies is unknown. Aims. The aims of this study were to quantify the amount of protein intake and to compare growth parameters at hospital discharge (as measured by discharge weight and head circumference percentiles) when using two different methodologies (BW vesrsus current daily weight until BW is regained) for calculating fluid and protein intake in the first two weeks after birth in ELBW infants. Methods. A retrospective review of infants weighing ≤ 1kg at birth was conducted from January 2005 to December 2009 (Phase 1; P1) and January 2012 to December 2014 (Phase 2; P2) in a tertiary care NICU. At this center, in P1 (2005-09) CW was exclusively used for calculating fluid, calorie, and protein administration till BW was regained. In P2 (2012-14), BW was exclusively used for all calculations. Both P1 and P2 periods were compared and analyzed for differences in demographics, nutritional intake, comorbid conditions, and growth outcomes. Results. We studied 146 infants with 84 and 62 infants in P1 and P2 periods, respectively. The mean gestational age was lower during Phase 1 (25.74 ±1.32 vs. 26.47 ±1.82 weeks. P value =0.01). However, the birth weights were not different between the two periods. When the multiple-regression analysis was done using a discharge weight of >10^th percentile as the dependent variable, protein intake before regaining of BW (OR of 4.126 with 95^th CI of 2.03-8.36, a P value of 0.00) and AGA status at birth (OR of 8.37 with 95^th CI of 2.67-26.24) remained significant factors. Compared to P1, babies in P2 received 1g/kg/day more protein till BW was regained. In P1, 27% of babies who were appropriate for gestational age (AGA) for head circumference at birth became microcephalic by discharge, compared to 15.6% in P2 (p=0.03). Similarly, 75.3% of the babies who were AGA for weight at birth in P1 became small for gestational age (SGA) by discharge, compared to 16.7% in P2 (p=<0.0001). The number of days it took to regain BW was 9.6 days in P1 vs. 7 days in P2 (p=<0.0001). Conclusions. Basing nutrition calculations in ELBW on birth weight rather than current daily weight until the birth weight is regained resulted in significantly greater protein delivery, a significant decrease in the incidence of failure to thrive and smaller head circumference percentiles at discharge in ELBW infants.

Growth and body composition in preterm newborns with bronchopulmonary dysplasia: a cohort study

Objective To compare growth and body composition of preterm infants (gestational age <32 weeks) with and without bronchopulmonary dysplasia (BPD). Methods A prospective cohort involving three neonatal units in the public health system of the Brazilian city of Rio de Janeiro. Inclusion: newborns with gestational age <32 weeks.

EXPOSURE

BPD. Anthropometric measurements were performed at birth and at 1 month of infant corrected age. Body composition was measured using an air displacement plethysmography (ADP) (PEA POD®) at 1 month of infant corrected age. Results Ninety-five newborns were eligible, of which 67 were included, 32.8% of them with BPD. Newborns with BPD presented lower gestational age at birth, greater need for resuscitation in the delivery room, received parenteral nutrition (PN) for a longer period of time, achieved lower weights during hospital stay and required more time to reach a full enteral diet. No statistically significant differences were observed in relation to anthropometric measurements and body composition at 1 month of infant corrected age between the groups with and without BPD. Conclusion This study, unlike previous ones, has shown that children who developed BPD were able to regain growth, as measured by anthropometric measures, with no change in body composition at 1 month of infant corrected age.

Human milk enriched with human milk lyophilisate for feeding very low birth weight preterm infants: A preclinical experimental study focusing on fatty acid profile

BACKGROUND

Human milk, with essential nutrients and long chain polyunsaturated fatty acids (LC-PUFAs) such as the omega 3 and 6 fatty acids is important for development of the central nervous system and the retina in very low birth weight infants (<1,500 g). However, breast milk may not be sufficient to meet these needs. The possibility of supplementing breast milk with a lyophilisate of human milk was explored in this study. The objectives of this study were to determine the total lipid content and the lipid profile of the Human Milk on Baseline (HMB) and that of the Concentrates with the Human Milk + lyophilisate (with lyophilisate of milk in the immediate period (HMCI), at 3 months (HMC3m), and at 6 months (HMC6m) of storage).

METHODS

Fifty donors from the Human Milk Bank of Children's Hospital provided consent, and donated milk samples. Macronutrient (including total lipids) quantification was performed using the MIRIS® Human Milk Analyzer, and the fatty acid profile was determined by gas chromatography (CG-FID, SHIMADZU®).

RESULTS

There was a higher lipid concentration in HMCI relative to HMB. The concentrations of the main fatty acids (% of total) were as follows: palmitic acid (C16:0) HMB, 22.30%; HMCI, 21.46%; HMC3m, 21.54%; and HMC6m, 21.95% (p<0.01); oleic acid (C18:1n-9) HMB, 30.41%; HMCI, 30.47%; HMC3m, 30.55%; and HMC6m, 29.79% (p = 0.46); linoleic acid (C18:2n-6) HMB, 19.62%; HMCI, 19.88%; HMC3m, 19.49%; and HMC6m, 19.45% (p = 0.58); arachidonic acid (C20:4n-6) HMB, 0.35%; HMCI, 0.16%; HMC3m, 0.13%; and HMC6m, 0.15% (p<0.01); α-linolenic acid (C18:3n-3) HMB,1.32%; HMCI, 1.37%; HMC3m, 1.34%; and 1.34% HMC6m (p = 0.14); docosahexaenoic acid (C22:6n-3) HMB, 0.10%; HMCI, 0.06%; HMC3m, 0.05%; and HMC6m, 0.06% (p<0.01). There were no significant changes in the lipid profile when stored. There was no evidence of peroxidation during storage.

CONCLUSIONS

Freeze-dried human milk fortified with a human milk concentrate brings potential benefits to newborns, mainly by preserving the essential nutrients present only in breast milk; however, further clinical studies are required to evaluate the safety and efficacy of the concentrate as a standard nutritional food option for very low birth weight infants.

Feeding Imprinting: The Extreme Test Case of Premature Infants Born With Very Low Birth Weight

Feeding imprinting, considered a survival-enabling process, is not well understood. Infants born very preterm, who first feed passively, are an effective model for studying feeding imprinting. Retrospective analysis of neonatal intensive care unit (NICU) records of 255 infants (M_{gestational age}  = 29.98 ± 1.64) enabled exploring the notion that direct breastfeeding (DBF) during NICU stay leads to consumption of more mother's milk and earlier NICU discharge. Results showed that DBF before the first bottle feeding is related to shorter transition into oral feeding, a younger age of full oral feeding accomplishment and earlier discharge. Furthermore, the number of DBF meals before first bottle feeding predicts more maternal milk consumption and improved NICU outcomes. Improved performance in response to initial exposure to DBF at the age of budding feeding abilities supports a feeding imprinting hypothesis.

Does High Protein Intake During First Week of Life Improve Growth and Neurodevelopmental Outcome at 18 months Corrected Age in Extremely Preterm Infants?

OBJECTIVE

To examine whether high protein intake during the first week of life alters the growth and neurodevelopmental outcomes at 18 mo corrected age (CA) in preterm infants born < 29 wk.

METHODS

This was a retrospective cohort study of preterm infants (<29 wk) before and after introduction of nutritional policy targeting higher protein intake during the first week of life. The authors compared the growth and neurodevelopmental outcomes at 18 mo CA between infants born before (epoch 1) and after (epoch 2) the introduction of nutrition policy.

RESULTS

Of 171 eligible infants who completed follow-up at 18 mo CA, 87 (51 %) were in post intervention group (epoch 2). The mean (± SD) gestational age (26.3 ± 1.49 wk vs. 26.2 ± 1.48 wk) and birth weight (947 ± 220 g vs. 924 ± 225 g) were similar between the two groups. At 18 mo CA, there were no significant differences in the growth and neurodevelopmental impairment rates between the two groups. Logistic regression analysis revealed that high protein intake (>3.5 g/kg/d) was not associated with improved neurodevelopmental outcome (OR 1.49, 95 % CI 0.52-4.26).

CONCLUSIONS

High protein intake during the first week of age was not associated with better growth or neurodevelopmental outcome at 18 mo CA in preterm infants.

hPSC-derived lung and intestinal organoids as models of human fetal tissue

In vitro human pluripotent stem cell (hPSC) derived tissues are excellent models to study certain aspects of normal human development. Current research in the field of hPSC derived tissues reveals these models to be inherently fetal-like on both a morphological and gene expression level. In this review we briefly discuss current methods for differentiating lung and intestinal tissue from hPSCs into individual 3-dimensional units called organoids. We discuss how these methods mirror what is known about in vivo signaling pathways of the developing embryo. Additionally, we will review how the inherent immaturity of these models lends them to be particularly valuable in the study of immature human tissues in the clinical setting of premature birth. Human lung organoids (HLOs) and human intestinal organoids (HIOs) not only model normal development, but can also be utilized to study several important diseases of prematurity such as respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), and necrotizing enterocolitis (NEC).

Effects of breast-feeding compared with formula-feeding on preterm infant body composition: a systematic review and meta-analysis

We conducted a systematic review and meta-analysis to compare the effect of breast-feeding and formula-feeding on body composition of preterm infants. We searched the literature using PubMed, Cochrane Central Library Issue, Ovid (Medline), Embase and other resources such as Google Scholar, electronic databases and bibliographies of relevant articles; two reviewers collected and extracted data independently. All the authors assessed risk of bias independently using the Newcastle-Ottawa Scale (NOS). A fixed-effects meta-analysis was undertaken with RevMan 5 software (The Cochrane Collaboration) using the inverse variance method (P≥0·05; χ 2 test). In contrast, a random-effects meta-analysis was carried out. Altogether, 630 articles were identified using search strategy, and the references within retrieved articles were also assessed. A total of six studies were included in this systematic review. In formula-fed infants, fat mass was higher at term (mean difference 0·24 (95 % CI 0·17, 0·31) kg), fat-free mass was higher at 36 weeks of gestational (mean difference 0·12 (95 % CI 0·04, 0·21) kg) and the percentage of fat mass was higher at 36 weeks of gestation (mean difference 3·70 (95 % CI 1·81, 5·59) kg) compared with breast-fed infants. Compared with breast-feeding, formula-feeding is associated with altered body composition from birth to term in preterm infants. The effects of formula-feeding on preterm infant body composition from term to 12-month corrected age are inconclusive in our study. Well-designed studies are required in the future to explore the effects of formula-feeding compared with breast-feeding.

Influence of gestational age and birth weight in neonatal cholesterol response to total parenteral nutrition

BACKGROUND

Premature and critically ill infants receiving total parenteral nutrition (TPN) are at risk for dyslipidemia, and altered cholesterol levels in early life may contribute to later cardiovascular risk. Data regarding plasma cholesterol response to TPN in young infants are lacking.

OBJECTIVE

To determine the changes in plasma cholesterol levels during the first week of life in infants receiving TPN and a comparison group of infants who did not receive TPN during routine care.

METHODS

In a prospective, pilot cohort study, 38 neonates (30 TPN vs. 8 No-TPN) underwent serial blood sampling during the first week of life. Gas chromatography-mass spectrometry was used to measure cholesterol in plasma and TPN administered to study participants.

RESULTS

Baseline cholesterol level was similar between groups. In contrast to infants who did not receive TPN, cholesterol levels during the first week of life were significantly higher than baseline in infants receiving TPN (maximum cholesterol response 34% vs. 103% change from baseline, No-TPN vs. TPN, respectively, P = .036). After adjusting for cumulative cholesterol received by infants receiving TPN, maximum cholesterol response remained inversely related to gestational age and birth weight (P < .05).

CONCLUSION

Plasma cholesterol significantly increases during the first week of life in neonates receiving TPN. A higher cholesterol response was induced by TPN in infants of lower gestational age and birth weight.

The ProVIDe study: the impact of protein intravenous nutrition on development in extremely low birthweight babies

BACKGROUND

Preterm birth and very small size at birth have long-term effects on neurodevelopment and growth. A relatively small percentage of extremely low birthweight babies suffer from severe neurological disability; however, up to 50% experience some neurodevelopmental or learning disability in childhood. Current international consensus is that increased protein intake in the neonatal period improves both neurodevelopment and growth, but the quantum of protein required is not known. This trial aims to assess whether providing an extra 1 to 2 g.kg(-1).d(-1) protein in the first 5 days after birth will improve neurodevelopmental outcomes and growth in extremely low birthweight babies.

METHODS/DESIGN

The ProVIDe study is a multicentre, two-arm, double-blind, parallel, randomised, controlled trial. In addition to standard intravenous nutrition, 430 babies with a birthweight of less than 1000 g who have an umbilical arterial line in situ will be randomised in 1:1 ratio to receive either an amino acid solution (TrophAmine®) or placebo (saline) administered through the umbilical arterial catheter for the first 5 days. Exclusion criteria are admission to neonatal intensive care more than 24 h after birth; multiple births of more than 2 babies; known chromosomal or genetic abnormality, or congenital disorder affecting growth; inborn error of metabolism, and in danger of imminent death.

PRIMARY OUTCOME

Survival free from neurodevelopmental disability at 2 years' corrected age, where neurodevelopmental disability is defined as cerebral palsy, blindness, deafness, developmental delay (standardised score more than 1 SD below the mean on the cognitive, language or motor subscales of the Bayley Scales of Infant Development Edition 3), or Gross Motor Function Classification System score ≥ 1.

SECONDARY OUTCOMES

Growth, from birth to 36 weeks' corrected gestational age, at neonatal intensive care discharge and at 2 years' corrected age; body composition at 36 to 42 weeks' corrected postmenstrual age and at 2 years' corrected age; neonatal morbidity, including length of stay; nutritional intake.

DISCUSSION

This trial will provide the first direct evidence of the effects of giving preterm babies a higher intake of intravenous protein in the first week after birth on neurodevelopmental outcomes at 2 years corrected age.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12612001084875.

Prevention of postnatal growth restriction by the implementation of an evidence-based premature infant feeding bundle

OBJECTIVE

To develop an evidence-based feeding bundle to safely decrease the rate of PNGR in VLBW infants.

STUDY DESIGN

The bundle was developed and implemented in January 2010, followed by 3 years of monitoring bundle compliance and infant outcomes (days to first feed (FD), days to reach full feeds (FF), and birth-discharge growth trajectories (delta z-score)).

RESULTS

Data were collected on 482 infants (119 pre-bundle). PNGR decreased from 35% to 19% (P<0.01) and weight delta z-score improved from -0.82 to -0.45 (P<0.001). Percentage of infants with head circumference (HC) below 10th percentile at discharge decreased from 21% to 9% (P<0.01) and HC delta z-score improved from -0.65 to -0.17 (P<0.001). FD and FF also decreased significantly. Rates of necrotizing enterocolitis, peak alkaline phosphatase and peak direct bilirubin levels all trended downward.

CONCLUSIONS

An evidence-based, standardized feeding bundle was safe and effective in reducing the rate of PNGR and in improving head growth in VLBW infants.

Kinetics of phytosterol metabolism in neonates receiving parenteral nutrition

BACKGROUND

Phytosterols in soybean oil (SO) lipids likely contribute to parenteral nutrition-associated liver disease (PNALD) in infants. No characterization of phytosterol metabolism has been done in infants receiving SO lipids.

METHODS

In a prospective cohort study, 45 neonates (36 SO lipid vs. 9 control) underwent serial blood sample measurements of sitosterol, campesterol, and stigmasterol. Mathematical modeling was used to determine pharmacokinetic parameters of phytosterol metabolism and phytosterol exposure.

RESULTS

Compared to controls, SO lipid-exposed infants had significantly higher levels of sitosterol and campesterol (P < 0.01). During SO lipid infusion, sitosterol and campesterol reached half of steady-state plasma levels within 1.5 and 0.8 d, respectively. Steady-state level was highest for sitosterol (1.68 mg/dl), followed by campesterol (0.98 mg/dl), and lowest for stigmasterol (0.01 mg/dl). Infants born < 28 wk gestational age had higher sitosterol steady-state levels (P = 0.03) and higher area under the curve for sitosterol (P = 0.03) during the first 5 d of SO lipid (AUC5) than infants born ≥ 28 wk gestational age.

CONCLUSION

Phytosterols in SO lipid accumulate rapidly in neonates. Very preterm infants receiving SO lipid have higher sitosterol exposure, and may have poorly developed mechanisms of eliminating phytosterols that may contribute to their vulnerability to PNALD.

Optimum feeding and growth in preterm neonates

Approximately 10% of all babies worldwide are born preterm, and preterm birth is the leading cause of perinatal mortality in developed countries. Although preterm birth is associated with adverse short- and long-term health outcomes, it is not yet clear whether this relationship is causal. Rather, there is evidence that reduced foetal growth, preterm birth and the long-term health effects of both of these may all arise from a suboptimal intrauterine environment. Further, most infants born preterm also experience suboptimal postnatal growth, with potential adverse effects on long-term health and development. A number of interventions are used widely in the neonatal period to optimise postnatal growth and development. These commonly include supplementation with macronutrients and/or micronutrients, all of which have potential short-term risks and benefits for the preterm infant, whereas the long-term health consequences are largely unknown. Importantly, more rapid postnatal growth trajectory (and the interventions required to achieve this) may result in improved neurological outcomes at the expense of increased cardiovascular risk in later life.

Enteral zinc supplementation and growth in extremely-low-birth-weight infants with chronic lung disease

OBJECTIVE

Zinc deficiency causes growth deficits. Extremely-low-birth-weight (ELBW) infants with chronic lung disease (CLD), also known as bronchopulmonary dysplasia, experience growth failure and are at risk for zinc deficiency. We hypothesized that enteral zinc supplementation would increase weight gain and linear growth.

METHODS

A cohort of infants was examined retrospectively at a single center between January 2008 and December 2011. CLD was defined as the need for oxygen at 36 weeks postmenstrual age. Zinc supplementation was started in infants who had poor weight gain. Infants' weight gain and linear growth were compared before and after zinc supplementation using the paired t test.

RESULTS

A total of 52 ELBW infants with CLD met entry criteria. Mean birth weight was 682 ± 183 g, and gestational age was 25.3 ± 2 weeks. Zinc supplementation started at postmenstrual age 33 ± 2 weeks. Most infants received fortified human milk. Weight gain increased from 10.9 before supplementation to 19.9 g · kg(-1) · day(-1) after supplementation (P < 0.0001). Linear growth increased from 0.7 to 1.1 cm/week (P = 0.001).

CONCLUSIONS

Zinc supplementation improved growth in ELBW infants with CLD receiving human milk. Further investigation is warranted to reevaluate zinc requirements, markers, and balance.

Review of macronutrients in parenteral nutrition for neonatal intensive care population

Parenteral nutrition (PN) has become essential in the management of sick and growing newborn populations in the NICU. In the past few decades, PN has become fundamental in the nutritional management of the very low birth weight infant (<1,500 g).1 Although the components in PN are commonly determined and ordered by the physician or neonatal nurse practitioner provider, the NICU nurse is responsible for confirming the components in the daily PN prior to infusion and is responsible for maintaining the infusion of PN. Nurses should understand the nutritional components of PN as well as the indications, side effects, and infusion limitations of each component. The purpose of this article is to review the macronutrients in PN, including carbohydrates, protein, and fat. A subsequent article will review the micronutrients in PN, including electrolytes, minerals, and vitamins.

Safety and efficacy of early parenteral lipid and high-dose amino acid administration to very low birth weight infants

OBJECTIVE

To assess the efficacy and safety of early parenteral lipid and high-dose amino acid (AA) administration from birth onwards in very low birth weight (VLBW, birth weight <1500 g) infants.

STUDY DESIGN

VLBW infants (n = 144; birth weight 862 ± 218 g; gestational age 27.4 ± 2.2 weeks) were randomized to receive 2.4 g of AA kg(-1) · d(-1) (control group), or 2.4 g AA kg(-1) · d(-1) plus 2-3 g lipids kg(-1) · d(-1) (AA + lipid group), or 3.6 g AA kg(-1) · d(-1) plus 2-3 g lipids kg(-1) · d(-1) (high AA + lipid group) from birth onwards. The primary outcome was nitrogen balance. The secondary outcomes were biochemical variables, urea rate of appearance, growth rates, and clinical outcome.

RESULTS

The nitrogen balance on day 2 was significantly greater in both intervention groups compared with the control group. Greater amounts of AA administration did not further improve nitrogen balance compared with standard AA dose plus lipids and was associated with high plasma urea concentrations and high rates of urea appearance. No differences in other biochemical variables, growth, or clinical outcomes were observed.

CONCLUSIONS

In VLBW infants, the administration of parenteral AA combined with lipids from birth onwards improved conditions for anabolism and growth, as shown by improved nitrogen balance. Greater levels of AA administration did not further improve the nitrogen balance but led to increased AA oxidation. Early lipid initiation and high-dose AA were well tolerated.

Three-dimensional digital capture of head size in neonates - a method evaluation

Introduction

The quality of neonatal care is mainly determined by long-term neurodevelopmental outcome. The neurodevelopment of preterm infants is related to postnatal head growth and depends on medical interventions such as nutritional support. Head circumference (HC) is currently used as a two-dimensional measure of head growth. Since head deformities are frequently found in preterm infants, HC may not always adequately reflect head growth. Laser aided head shape digitizers offer semiautomatic acquisition of HC and cranial volume (CrV) and could thus be useful in describing head size more precisely.

Aims

1) To evaluate reproducibility of a 3D digital capture system in newborns. 2) To compare manual and digital HC measurements in a neonatal cohort. 3) To determine correlation of HC and CrV and predictive value of HC.

Methods

Within a twelve-month period data of head scans with a laser shape digitizer were analysed. Repeated measures were used for method evaluation. Manually and digitally acquired HC was compared. Regression analysis of HC and CrV was performed.

Results

Interobserver reliability was excellent for HC (bias-0.005%, 95% Limits of Agreement (LoA) −0.39–0.39%) and CrV (bias1.5%, 95%LoA-0.8–3.6%). Method comparison data was acquired from 282 infants. It revealed interchangeability of the methods (bias-0.45%; 95%LoA-4.55–3.65%) and no significant systematic or proportional differences. HC and CrV correlated (r² = 0.859, p<0.001), performance of HC predicting CrV was poor (RSD ±24 ml). Correlation was worse in infants with lower postmenstrual age (r² = 0.745) compared to older infants (r² = 0.843).

Discussion

The current practice of measuring HC for describing head growth in preterm infants could be misleading since it does not represent a 3D approach. CrV can vary substantially in infants of equal HC. The 3D laser scanner represents a new and promising method to provide reproducible data of CrV and HC. Since it does not provide data on cerebral structures, additional imaging is required.

Enterale Ernährung von Frühgeborenen

Unmittelbar postnatal ist bei Frühgeborenen der rasche Beginn einer vollständigen parenteralen Ernährung zur Fortsetzung des physiologischen intrauterinen umbilikalen Nährstofftransports notwendig, da die Energiereserven gering sind, Katabolismus verhindert werden soll und die Entwicklung des Gehirns nicht beeinträchtigt werden darf (Huppi 2008). Bei einem 1000 g schweren Frühgeborenen beträgt die zirkulierende Glukosemenge ca. 0,15 g und ist nach ca. 8 min verbraucht; der Glykogenspeicher beträgt 5 g und reicht etwa 5 h.

Nutritional strategies and growth in extremely low birth weight infants with bronchopulmonary dysplasia over the past 10 years

OBJECTIVE

Changes in nutritional strategies over the past decade have been shown to improve postnatal growth in extremely low birth weight (ELBW) infants. We showed 10 years ago that the majority of these ELBW infants with bronchopulmonary dysplasia (BPD) suffer postnatal growth failure. We theorized that recent changes in nutritional support strategies would positively affect growth outcomes in ELBW infants with BPD.

STUDY DESIGN

A retrospective study of 88 ELBW infants with BPD. Nutritional data, postnatal growth and BPD severity were compared across three cohorts: (1) weight gain ≤14 g kg(-1) per day, (2) 14.1 to 16 g kg(-1) per day and (3) ≥16 g kg(-1) per day from return to birth weight through discharge. We also compared these to a historical cohort.

RESULT

In all, 73% of current subjects grew at or above fetal rates. There was less extrauterine growth restriction (EUGR) by weight and head circumference for those ELBW infants with BPD receiving higher amounts of protein. Aggressive early TPN and receipt of caloric-dense milk seemed to be the 'new' nutritional strategies improving growth for current ELBW infants with BPD compared with those 10 years ago.

CONCLUSION

Despite a diagnosis of BPD, improved nutritional strategies have enhanced postnatal growth in infants at high risk for EUGR.

Modeling the glucose regulatory system in extreme preterm infants

BACKGROUND

Premature infants represent a significant proportion of the neonatal intensive care population. Blood glucose homeostasis in this group is often disturbed by immaturity of endogenous regulatory systems and the stress of their condition. Hypo- and hyperglycemia are frequently reported in very low birth weight infants, and more mature infants often experience low levels of glycemia. A model capturing the unique fundamental dynamics of the neonatal glucose regulatory system could be used to develop better blood glucose control methods.

METHODS

A metabolic system model is adapted from adult critical care to the unique physiological case of the neonate. Integral-based fitting methods were used to identify time-varying insulin sensitivity and non-insulin mediated glucose uptake profiles. The clinically important predictive ability of the model was assessed by assuming insulin sensitivity was constant over prediction intervals of 1, 2 and 4h forward and comparing model-simulated versus actual clinical glucose values for all recorded interventions. The clinical data included 1091 glucose measurements over 3567 total patient hours, along with all associated insulin and nutritional infusion data, for N=25 total cases. Ethics approval was obtained from the Upper South A Regional Ethics Committee for this study.

RESULTS

The identified model had a median absolute percentage error of 2.4% [IQR: 0.9-4.8%] between model-fitted and clinical glucose values. Median absolute prediction errors at 1-, 2- and 4-h intervals were 5.2% [IQR: 2.5-10.3%], 9.4% [IQR: 4.5-18.4%] and 13.6% [IQR: 6.3-27.6%] respectively.

CONCLUSIONS

The model accurately captures and predicts the fundamental dynamic behaviors of the neonatal metabolism well enough for effective clinical decision support in glycemic control. The adaptation from adult to a neonatal case is based on the data from the literature. Low prediction errors and very low fitting errors indicate that the fundamental dynamics of glucose metabolism in both premature neonates and critical care adults can be described by similar mathematical models.

Standard fortification of preterm human milk fails to meet recommended protein intake: Bedside evaluation by Near-Infrared-Reflectance-Analysis

BACKGROUND

Protein content of preterm human milk (HM) is relatively low and extremely variable among mothers: thus, recommended protein intake is rarely met.

OBJECTIVES

To evaluate in a NICU setting if HM protein content after standard fortification meets the recommended intake, and also to check the effect of fortification on the osmolality of HM, as an index of feeding intolerance.

METHODS

Protein content of 34 preterm HM samples was evaluated by a bedside technique (Near-Infrared-Reflectance-Analysis - NIRA); osmolality was also checked. Seventeen samples were fortified with Aptamil BMF, Milupa (Group A) and 17 with FM85, Nestlé (Group B). Fortification was performed as recommended by the manufacturer ("full fortification [FF]") and also with a lower amount of fortifier ("low-dose fortification [LF]"). After fortification, actual protein content was calculated and compared to that needed to meet recommended intake (2.33-3g/dl), and osmolality was measured.

RESULTS

After FF, protein content was above 3g/dl in none of the samples, and below 2.33 g/dl in 16/34 samples (11 in Group A, 5 in Group B). After LF, protein content was above 3g/dl in none of the samples and below 2.33 g/dl in 32/34 samples (15 in Group A, 17 in Group B). Osmolality exceeded 400 mOsm/kg in 19 samples after FF (10 in Group A, 9 in Group B) and in 2/34 samples after LF (1 in each group).

CONCLUSION

HM protein content after standard fortification fails to meet the recommended intake for preterm infants in approximately half of the cases.

Growth and body composition in very young SGA children

Infants with a very low birth weight are at risk of a reduced number of nephrons predisposing to kidney disorder, hypertension, and metabolic syndrome. Approximately 3% of infants are born small for gestational age (SGA), defined as birth weight and/or length at least 2 SD below the mean for gestational age (GA), independently of whether these children are born prematurely or at term. About 10% of these children do not show postnatal catch-up growth and remain of short stature during childhood. Most of these infants are not growth hormone (GH)-deficient, but may have GH resistance. Although GH-resistant, the majority of patients benefit from GH therapy, normalize height during childhood, maintain a normal growth velocity during puberty, and attain a normal adult height. To date, GH has been shown to be safe and no significant adverse effects have been demonstrated. Children with congenital chronic kidney disease (CKD) are born with subnormal birth weight and length and about 25% are born SGA. Shortness and need for GH treatment is highly correlated with weight at birth and gestational age. Primary renal disorders modify the response to GH treatment. Analysis of whether SGA is an additional risk factor for CKD regarding the development of hypertension, metabolic syndrome and cardiovascular complications is required.

Protein content and fortification of human milk influence gastroesophageal reflux in preterm infants

OBJECTIVES

: Preterm human milk (HM) may provide insufficient energy and nutrients and thus may need to be fortified. Our aim was to determine whether fat content, protein content, and osmolality of HM before and after fortification may affect gastroesophageal reflux (GER) in symptomatic preterm infants.

METHODS

: Gastroesophageal reflux was evaluated in 17 symptomatic preterm newborns fed naïve and fortified HM by combined pH/intraluminal-impedance monitoring (pH-MII). Human milk fat and protein content was analysed by a near-infrared reflectance analysis. Human milk osmolality was tested before and after fortification. Gastroesophageal reflux indexes measured before and after fortification were compared and were also related to HM fat and protein content and osmolality before and after fortification.

RESULTS

: An inverse correlation was found between naïve HM protein content and acid reflux index (RIpH: P = 0.041, rho =-0.501). After fortification, osmolality often exceeded the values recommended for infant feeds; furthermore, a statistically significant (P < 0.05) increase in nonacid reflux indexes was observed.

CONCLUSIONS

: Protein content of naïve HM may influence acid GER in preterm infants. A standard fortification of HM may worsen nonacid GER indexes and, due to the extreme variability in HM composition, may overcome both recommended protein intake and HM osmolality. Thus, an individualised fortification, based on the analysis of the composition of naïve HM, could optimise both nutrient intake and feeding tolerance.

Initial nutritional management of the preterm infant

Postnatal nutrition has a large impact on long-term outcome of preterm infants. Evidence is accumulating showing even a relationship between nutrient supply in the first week of life and later cognitive development in extremely low birth weight infants. Since enteral nutrition is often not tolerated following birth, parenteral nutrition is necessary. Yet, optimal parenteral intakes of both energy and amino acids are not well established. Subsequently, many preterm infants fail to grow well, with long-term consequences. Early and high dose amino acid administration has been shown to be effective and safe in very low birth weight infants, but the effect of additional lipid administration needs to be defined.

Blood glucose controller for neonatal intensive care: virtual trials development and first clinical trials

BACKGROUND

Premature neonates often experience hyperglycemia, which has been linked to worsened outcomes. Insulin therapy can assist in controlling blood glucose (BG) levels. However, a reliable, robust control protocol is required to avoid hypoglycemia and to ensure that clinically important nutrition goals are met.

METHODS

This study presents an adaptive, model-based predictive controller designed to incorporate the unique metabolic state of the neonate. Controller performance was tested and refined in virtual trials on a 25-patient retrospective cohort. The effects of measurement frequency and BG sensor error were evaluated. A stochastic model of insulin sensitivity was used in control to provide a guaranteed maximum 4% risk of BG < 72 mg/dl to protect against hypoglycemia as well as account for patient variability over 1-3 h intervals when determining the intervention. The resulting controller is demonstrated in two 24 h clinical neonatal pilot trials at Christchurch Women's Hospital.

RESULTS

Time in the 72-126 mg/dl BG band was increased by 103-161% compared to retrospective clinical control for virtual trials of the controller, with fewer hypoglycemic measurements. Controllers were robust to BG sensor errors. The model-based controller maintained glycemia to a tight target control range and accounted for interpatient variability in patient glycemic response despite using more insulin than the retrospective case, illustrating a further measure of controller robustness. Pilot clinical trials demonstrated initial safety and efficacy of the control method.

CONCLUSIONS

A controller was developed that made optimum use of the very limited available BG measurements in the neonatal intensive care unit and provided robustness against BG sensor error and longer BG measurement intervals. It used more insulin than typical sliding scale approaches or retrospective hospital control. The potential advantages of a model-based approach demonstrated in simulation were applied to initial clinical trials.

Nutritional practices and growth velocity in the first month of life in extremely premature infants

OBJECTIVES

The goals of this study were to describe nutritional practices in the first month of life for a large cohort of extremely low gestational age newborns and to determine the impact of these nutritional practices on growth velocity (GV) over the same period.

METHODS

The sample included 1187 infants born at 23 to 27 weeks of gestation, at 14 institutions, between 2002 and 2004. Inclusion criteria included survival until day 28 and weight information for days 7 and 28. GV, expressed as grams per kilogram per day, was calculated for the interval between days 7 and 28. Nutritional practices during the first week and on days 14, 21, and 28 were compared with current nutritional guidelines in the literature. Multivariable logistic regression models estimated the contribution of limited nutrition to limited GV.

RESULTS

Protein and fat delivery approximated current nutritional recommendations, whereas carbohydrate and total energy intake delivery did not. Despite this, GV of our study infants exceeded the current guideline of 15 g/kg per day. Nevertheless, we found extrauterine growth restriction (ie, weight for gestational age below the 10th centile) in 75% of the infants at 28 days, compared with only 18% at birth. A GV of 20 to 30 g/kg per day was associated with infants' maintaining or exceeding their birth weight z score, with rates in the upper range for the gestationally youngest infants. Early (day 7) nutritional practices were positively associated with GV measured between days 7 and 28.

CONCLUSION

The early provision of nutrients is an important determinant of postnatal growth. Extrauterine growth restriction remains high in extremely premature infants even when they achieve a GV rate within current guidelines.

Optimizing growth in the preterm infant

Most very low birth weight preterm infants experience postnatal growth failure in the neonatal ICU. In an attempt to minimize this phenomenon, the nutritional support of these infants has tended to become more aggressive in recent years and has become a focus of much study. Despite this attention, many questions remain unresolved. This article examines several of these issues, including the controversies regarding optimal postnatal growth velocity, early aggressive nutritional support, and the transition to enteral nutrition in preterm infants.

Extrauterine growth restriction: a review of the literature

Extrauterine growth restriction (EUGR) is a common condition in very low birth weight (VLBW) preterm infants (< or = 1,500 g). Most affected infants have a birth weight that is average for gestational age, but by the time of hospital discharge have a weight that is less than the tenth percentile for corrected gestational age. EUGR is the most frequent morbidity among VLBW survivors at their time of discharge from the hospital. Studies to elucidate the causes of EUGR have been inconclusive. Recent research has found an association between EUGR, developmental outcomes, and long-term morbidity. Low birth weight has also been associated with chronic diseases later in life. These findings emphasize the critical nature of understanding the phenomenon of EUGR and ways it can be prevented.

Insulin infusion for the treatment of hyperglycemia in low birth weight infants: examining the evidence

FORTY TO 80 PERCENT OF VERY LOW birth weight (VLBW) (infants <1,500 g) and extremely low birth weight (ELBW) (infants <1,000 g) infants will develop hyperglycemia when provided with glucose infusions adequate to meet basal metabolic needs.1,2 Avoiding hyperglycemia while providing adequate nutrition to promote growth and development is a major challenge for health care providers in the NICU. Some health care providers suggest that the judious use of continuous insulin infusion (CII) may provide the opportunity for increasing nutritional support while maintaining euglycemia. A systematic review of the literature is presented to evaluate the evidence supporting this practice.

Nutrient composition of hindmilk produced by mothers of very low birth weight infants born at less than 28 weeks' gestation

The objectives of this study were to describe and compare retinol, alpha-tocopherol and gamma-tocopherol, fat, energy, and nitrogen concentrations between the foremilk and hindmilk fractions of 24-hour milk collected by 24 mothers of very preterm (< 28 weeks' gestation) infants and to relate milk vitamins A and E content to maternal vitamin intake. Concentrations of retinol were significantly higher in hindmilk than in foremilk (1.6-fold), as were concentrations of alpha-tocopherol (1.6-fold), gamma-tocopherol (1.5-fold), fat (1.7-fold), energy (1.3-fold), and nitrogen (1.05-fold). Retinol, alpha-tocopherol, and gamma-tocopherol were positively related (P < .05) to milk fat and energy but not to maternal intake. Estimates of vitamins A and E intakes of infants fed hindmilk with added human milk fortifier surpassed current recommended upper level of intakes. The higher fat-soluble vitamin content of hindmilk produced by mothers of very low birth weight infants needs to be considered in the design and recommendations for use of human milk fortifier.

Fluid regimens in the first week of life may increase risk of patent ductus arteriosus in extremely low birth weight infants

BACKGROUND

High fluid volumes may increase neonatal morbidity. However, evidence supporting fluid restriction is inconclusive and restricting fluids may restrict caloric intake.

OBJECTIVE

To determine if higher fluid intake was associated with increased risk of patent ductus arteriosus (PDA) or bronchopulmonary dysplasia (BPD) in extremely low birth weight (ELBW) infants.

STUDY DESIGN

A total of 204 ELBW (<or=32 weeks, <or=1250 g) infant survivors were grouped into low-, intermediate- and high-fluid groups. chi2 analyzed proportions of subjects with and without morbidities across groups. Logistic regression quantified increased risk of PDA or BPD associated with fluid intake while controlling for confounders. Analysis of variance compared differences in caloric intake across groups.

RESULT

After controlling for gestational age, severity of illness and weight change, fluid intake on day 2 (odds ratio (OR) 1.014; confidence interval (CI) 1.001 to 1.028) and day 3 (OR 1.022; CI 1.004 to 1.040) was associated with increased risk of PDA.

CONCLUSION

High fluid intake (>170 ml kg(-1) day(-1)) in the first days of life is associated with increased risk of PDA.

Growth of low birth weight preterm children

Very low birth weight premature (VLBWPT) infants demonstrate growth patterns in the early years of life which differ from those of term and large low birth weight preterm (LBWPT) peers. Optimal post natal growth of VLBWPT children is associated with more positive later health and neurodevelopmental outcomes. The neonatologist engaged in the follow of care of VLBWPT infants after discharge from the Neonatal Intensive Care Unit should monitor over time the velocity of weight, length, head circumference and weight/length ratio utilizing appropriate growth references. VLBW children who demonstrate atypically low weight gain in the early years of life have a higher probability of less than optimal cognitive development over time, while those with excessive weight gain have a greater likelihood of later childhood and adult obesity, cardiovascular disease, and diabetes. Nutritional planning should provide adequate calories for gradual normalization in all growth variables, while attempting to avoid atypically low or excessive weight gain. This nutritional planning should take into account the child's genetic growth potential, small for gestational age (SGA) or at gestational age (AGA), and clinical issues such as the presence of diseases like gastroesophageal (GE) reflux or chronic lung disease. Whatever nutritional approach is used, the neonatologist in follow up should track weight, length, head circumference, and weight/length ratio and adjust the nutrition plan and caloric intake to assure gradual return to normal in all growth variables while avoiding excessive weight gain.

Evaluation of postnatal weight growth in very low birth weight infants

There is general agreement about the need for longitudinal studies of very low birth weight infants (VLBWI) to evaluate their postnatal growth and to generate distance and velocity charts that allow neonatologists and pediatricians to detect earlier whether a child is not growing adequately. There are no satisfactory growth charts for VLBWI. We analyzed the weight growth of 262 VLBWIs from birth to 2 years of corrected age. Individual growth profiles were fitted with a 7-constant exponential-logistic function suitable for modelling weight growth pattern. After a postnatal weight loss, all VLBWIs showed a late neonatal peak of velocity between the seventh and 21st weeks; the large majority of them also experienced an early neonatal peak between the second and the sixth weeks. Small-for-gestational-age VLBWIs with major morbidities grew less than reference appropriate-for-gestational-age VLBWIs without major morbidities: at 2 years, the difference in weight was about 860 g. The more severe growth impairment in VLBWIs with major morbidities was almost entirely due to the reduced height of the late neonatal peak of velocity. The mathematical function used in this study is expected to be a useful tool to trace model-based longitudinal distance and velocity charts specific for VLBWIs. Moreover, this function also could be used to evaluate to what extent different pathological conditions or nutritional and medical care protocols affect growth kinetics.

Postnatal growth failure in preterm infants: ascertainment and relation to long-term outcome

OBJECTIVE

Traditional measure of postnatal growth failure assessment has poor discriminatory power for long-term outcomes. Our objective was to identify measure of postnatal growth failure associated with long-term outcome in preterm infants born at < 28 weeks' gestation.

PATIENTS AND METHODS

Four measures of defining postnatal growth failure at 36 weeks corrected gestational age: (1) weight < 10(th) centile, (2) weight < 3(rd) centile, (3) z score difference from birth > 1 and, (4) z score difference from birth > 2; were compared for their predictive values and strength of association with adverse neurodevelopmental outcomes at 18-24 months.

RESULTS

Postnatal growth failure defined as a decrease in z score of > 2 between birth and 36 weeks corrected gestational age had the best predictive values compared to other postnatal growth failure measures, however, it was significantly associated with psychomotor developmental (P=0.006) but not with mental developmental indices (P=0.379).

CONCLUSION

Postnatal growth failure defined by z score change influenced psychomotor but not mental tasks in this cohort. This method of ascertainment could be useful to identify infants who might benefit from nutritional interventions.