Nutritional therapies in the neonatal intensive care unit and post-natal growth outcomes of preterm very low birthweight Asian infants

Birth anthropometry among three Asian racial groups in Singapore: proposed new growth charts

OBJECTIVE

We analysed birth anthropometry of babies of Chinese, Malay and Indian ancestry living in Singapore with an aim to develop gestational age (GA) and gender-specific birth anthropometry charts and compare these with the widely used Fenton charts.

DESIGN

Retrospective observational study.

SETTING

Department of Neonatology, National University Hospital, Singapore.

POPULATION

We report data from 52 220 infants, born between 1991-1997 and 2010-2017 in Singapore.

METHODS

Anthropometry charts were built using smoothened centile curves and compared with Fenton's using binomial test. Birth weight (BW), crown-heel length and head circumference (HC) were each modelled with maternal exposures using general additive model.

MAIN OUTCOME MEASURES

BW, crown-heel length and HC.

RESULTS

There were 22 248 Chinese (43%), 16 006 Malay (31%) and 8543 Indian (16%) babies. Mean BW was 3103 g (95% CI 3096 to 3109), 3075 g (95% CI 3067 to 3083) and 3052 g (95% CI 3041 to 3062) for Chinese, Malays and Indians, respectively. When exposed to a uniform socioeconomic environment, intrauterine growth and birth anthropometry of studied races were almost identical. From our GA-specific anthropometric charts until about late prematurity, Asian growth curves mirrored that of Fenton's; thereafter, Asian babies showed a reduction in growth velocity.

CONCLUSIONS

These findings suggest that Asian babies living in relatively uniform socioeconomic strata exhibit similar growth patterns. There is a slowing of growth among Asian babies towards term, prompting review of existing birth anthropometry charts. The proposed charts will increase accuracy of identification of true fetal growth restriction as well as true postnatal growth failure in preterm infants when applied to the appropriate population.

Neonatal morbidities and postnatal growth failure in very low birth weight, very preterm infants

AIM

To assess postnatal growth in infants with and without major neonatal morbidities.

METHODS

This study is based on analysis of data collected by the Israel Neonatal Network on VLBW infants (≤1500 g) born in Israel from 2009 to 2018. Postnatal growth was assessed in two 5 years epochs: 2009-2013 (n = 4583) and 2014-2018 (n = 4558). Outcome was considered as severe, mild and no postnatal growth failure (PNGF). Morbidities included respiratory distress syndrome, bronchopulmonary dysplasia, necrotising enterocolitis, patent ductus arteriosus and grades 3-4 intraventricular haemorrhage. Multinomial logistic regression analyses with the generalised estimating equation approach were applied.

RESULTS

The study population composed 9141 infants. Of them, 2089 had at least one major morbidity and 7052 infants had none. In infants with no morbidities, 2.1% had severe PNGF, 23.7% mild PNGF and 74.2% had no PNGF, as compared to 13.6%, 43.9% and 42.5%, respectively, in infants with any major neonatal morbidity (p < 0.0001).

CONCLUSION

Despite enormous advances in neonatal care, postnatal growth remains a challenge in VLBW infants, particularly in infants with major neonatal morbidities. Along with efforts to decrease morbidity, a more personalised plan and follow-up may be required in infants with major morbidities, given their high risk for diminished growth and potentially, adverse neurodevelopmental outcomes.

A Systematic Review and Meta-Analysis of Human Milk Feeding and Short-Term Growth in Preterm and Very Low Birth Weight Infants

Human milk (HM) is the gold standard for feeding infants but has been associated with slower growth in preterm infants compared with preterm formula. This systematic review and meta-analysis summarises the post-1990 literature to examine the effect of HM feeding on growth during the neonatal admission of preterm infants with birth weight ≤1500 g and/or born ≤28 weeks’ gestation. Medline, PubMed, CINAHL, and Scopus were searched, and comparisons were grouped as exclusive human milk (EHM) vs. exclusive preterm formula (EPTF), any HM vs. EPTF, and higher vs. lower doses of HM. We selected studies that used fortified HM and compared that with a PTF; studies comparing unfortified HM and term formula were excluded. Experimental and observational studies were pooled separately. The GRADE system was used to evaluate risk of bias and certainty of evidence. Forty-four studies were included with 37 (n = 9963 infants) included in the meta-analyses. In general, due to poor quality studies, evidence of the effect of any HM feeds or higher versus lower doses of HM was inconclusive. There was a possible effect that lower doses of HM compared with higher doses of HM improved weight gain during the hospital admission, and separately, a possible effect of increased head circumference growth in infants fed EPTF vs. any HM. The clinical significance of this is unclear. There was insufficient evidence to determine the effects of an exclusive HM diet on any outcomes.

High versus standard volume enteral feeds to promote growth in preterm or low birth weight infants

BACKGROUND

Human milk is the best enteral nutrition for preterm infants. However, human milk, given at standard recommended volumes, is not adequate to meet the protein, energy, and other nutrient requirements of preterm or low birth weight infants. One strategy that may be used to address the potential nutrient deficits is to give a higher volume of enteral feeds. High volume feeds may improve nutrient accretion and growth, and in turn may improve neurodevelopmental outcomes. However, there are concerns that high volume feeds may cause feed intolerance, necrotising enterocolitis, or complications related to fluid overload such as patent ductus arteriosus and chronic lung disease. This is an update of a review published in 2017.

OBJECTIVES

To assess the effect on growth and safety of high versus standard volume enteral feeds in preterm or low birth weight infants. In infants who were fed fortified human milk or preterm formula, high and standard volume feeds were defined as > 180 mL/kg/day and ≤ 180 mL/kg/day, respectively. In infants who were fed unfortified human milk or term formula, high and standard volume feeds were defined as > 200 mL/kg/day and ≤ 200 mL/kg/day, respectively.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search Cochrane Central Register of Controlled Trials (CENTRAL; 2020 Issue 6) in the Cochrane Library; Ovid MEDLINE (1946 to June 2020); Embase (1974 to June 2020); and CINAHL (inception to June 2020); Maternity & Infant Care Database (MIDIRS) (1971 to April 2020); as well as previous reviews, and trial registries.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared high versus standard volume enteral feeds for preterm or low birth weight infants.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trial eligibility and risk of bias and independently extracted data. We analysed treatment effects in individual trials and reported risk ratio (RR) and risk difference for dichotomous data, and mean difference (MD) for continuous data, with respective 95% confidence intervals (CIs). We used the GRADE approach to assess the certainty of evidence. The primary outcomes were weight gain, linear and head growth during hospital stay, and extrauterine growth restriction at discharge.

MAIN RESULTS

We included two new RCTs (283 infants) in this update. In total, we included three trials (347 infants) in this updated review. High versus standard volume feeds with fortified human milk or preterm formula Two trials (283 infants) met the inclusion criteria for this comparison. Both were of good methodological quality, except for lack of masking. Both trials were performed in infants born at < 32 weeks' gestation. Meta-analysis of data from both trials showed high volume feeds probably improves weight gain during hospital stay (MD 2.58 g/kg/day, 95% CI 1.41 to 3.76; participants = 271; moderate-certainty evidence). High volume feeds may have little or no effect on linear growth (MD 0.05 cm/week, 95% CI -0.02 to 0.13; participants = 271; low-certainty evidence), head growth (MD 0.02 cm/week, 95% CI -0.04 to 0.09; participants = 271; low-certainty evidence), and extrauterine growth restriction at discharge (RR 0.71, 95% CI 0.50 to 1.02; participants = 271; low-certainty evidence). We are uncertain of the effect of high volume feeds with fortified human milk or preterm formula on the risk of necrotising enterocolitis (RR 0.74, 95% CI 0.12 to 4.51; participants = 283; very-low certainty evidence). High versus standard volume feeds with unfortified human milk or term formula One trial with 64 very low birth weight infants met the inclusion criteria for this comparison. This trial was unmasked but otherwise of good methodological quality. High volume feeds probably improves weight gain during hospital stay (MD 6.2 g/kg/day, 95% CI 2.71 to 9.69; participants = 61; moderate-certainty evidence). The trial did not provide data on linear and head growth, and extrauterine growth restriction at discharge. We are uncertain as to the effect of high volume feeds with unfortified human milk or term formula on the risk of necrotising enterocolitis (RR 1.03, 95% CI 0.07 to 15.78; participants = 61; very low-certainty evidence).

AUTHORS' CONCLUSIONS

High volume feeds (≥ 180 mL/kg/day of fortified human milk or preterm formula, or ≥ 200 mL/kg/day of unfortified human milk or term formula) probably improves weight gain during hospital stay. The available data is inadequate to draw conclusions on the effect of high volume feeds on other growth and clinical outcomes. A large RCT is needed to provide data of sufficient quality and precision to inform policy and practice.

Nutritional practices and growth of preterm infants in two neonatal units in the UK and Malaysia: a prospective exploratory study

OBJECTIVE

To explore differences in nutritional practices and growth outcomes among preterm infants in neonatal units in Malaysia and the UK.

DESIGN

Prospective exploratory study of infants born at <34 weeks gestational age (GA).

SETTING

Two neonatal units, one in Malaysia and one in the UK (May 2019 to March 2020).

METHODS

Data collected from birth until discharge and compared between units.

RESULTS

From 100 infants included, median GA (IQR) was 31 (30-33) and mean±SD birth weight was 1549±444 g. There were more small-for-gestational age infants in Malaysian unit: 12/50 (24%) vs UK: 3/50 (6%), p=0.012 and more morbidities. More Malaysian infants received breast milk (Malaysia: 49 (98%) vs UK: 38 (76%), p=0.001), fortified breast milk (Malaysia: 43 (86%) vs UK: 13 (26%), p<0.001) and exclusive breast milk at discharge (Malaysia: 26 (52%) vs UK: 16 (32%), p=0.043). There was higher parenteral nutrition use among Malaysian infants (40/50 (80%)) vs UK (19/50 (38%)) (p<0.001) with higher protein intake (mean±SD Malaysia: 3.0±0.5 vs UK: 2.7±0.6 g/kg/d, p=0.004) in weeks 1-4 and smaller cumulative protein deficits (mean±SD Malaysia: 11.4±6.1 vs UK: 15.4±8.0 g/kg, p=0.006). There were no significant differences in short-term growth between units and more than half of the infants in both units had ≥1.28 changes in weight-for-age Z-score at discharge (p=0.841).

CONCLUSIONS

An exploratory comparison of practices showed differences in patient characteristics and nutritional practices which impacted growth. Future studies with larger sample sizes and detailed analysis of maternal characteristics and infants' outcomes are needed for improving care of preterm infants in all settings.