A randomised controlled trial of high vs low volume initiation and rapid vs slow advancement of milk feeds in infants with birthweights ≤ 1000 g in a resource-limited setting

The Practice of Enteral Nutrition: Clinical Evidence for Feeding Protocols

Establishing full enteral nutrition in critically ill preterm infants with immature gastrointestinal function is challenging. In this article, we will summarize emerging clinical evidence from randomized clinical trials suggesting the feasibility and efficacy of feeding interventions targeting the early establishment of full enteral nutrition. We will also examine trial outcomes of higher volume feedings after the establishment of full enteral nutrition. Only data from randomized clinical trials will be discussed extensively. Future opportunities for clinical research will also be presented.

Trend and Predictors of Breastmilk Feeding among Very-Low-Birth-Weight Infants in NICU and at Discharge

Mothers' own milk (MOM) for premature babies is considered a life-saving drug for its proven protective action against the complications of prematurity and for effects on outcome in the short and long term, especially neurological ones. We studied the use of MOM for infants weighing <1500 g for a period of 5 years, evaluating the trend over time and the impact of some variables on human milk feeding performance. Statistical comparisons concerned the rate of feeding with breast milk during a stay in an NICU and at discharge with respect to two types of variables: (1) maternal and neonatal characteristics (gestational age, birth weight, type of pregnancy (whether single or twin), maternal age) and (2) feeding characteristics (time of the start of minimal enteral feeding and availability of MOM, days until the achievement of full enteral feeding). Group comparisons were performed using ANOVA or t-test for continuous variables and Pearson chi-squared test or Fisher exact test for categorical variables. We observed an increase, between 2017 and 2021, in MOM use (p = 0.003). The availability of the own mothers' milk occurred, on average, on the fourth day of life and improved over the years. The start of minimal enteral feeding (MEF) with human milk averaged 1.78 days, and 54.3% of VLBWs received MEF with donor milk on the first day of life. The average percentage of feeding with the mothers' milk at discharge was 47.6%, with 36.1% of exclusive MOM and an increase from 45.8% in 2017 (33.3% exclusive) to 58.82% (41.18% exclusive) in 2021. The mean average daily growth of the weight improved (p < 0.001) during this period, and there was no statistical difference between infants fed with maternal milk and those fed with bank milk. Older maternal age, early-start feeding with maternal milk and low gestational age had a statistically significant impact on feeding with MOM at discharge.

Fast Feed Advancement for Preterm and Low Birth Weight Infants: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Fast feed advancement may reduce hospital stay and infection but may increase adverse outcomes in preterm and low birth weight infants. The objective of this study was to assess effects of fast feed advancement (≥30 ml/kg per day) compared with slow feed advancement (<30 ml/kg per day) in preterm and low birth weight infants.

METHODS

Data sources include Medline, Scopus, Web of Science, CINAHL, and Index Medicus through June 30, 2021. Randomized trials were selected. Primary outcomes were mortality, morbidity, growth, and neurodevelopment. Data were extracted and pooled using random-effects models. The Cochrane Risk of Bias 2 tool was used.

RESULTS

A total of 12 RCTs with 4291 participants were included. At discharge, there was moderate certainty evidence that fast advancement likely slightly reduces the risk of: mortality (relative risk [RR] 0.93, 95% confidence interval [95% CI] 0.73 to 1.18, I2 = 18%, 11 trials, 4132 participants); necrotizing enterocolitis (RR 0.89, 95% CI 0.68 to 1.15, I2 = 0%, 12 trials, 4291 participants); sepsis (RR 0.92, 95% CI 0.83 to 1.03, I2 = 0%, 9 trials, 3648 participants); and feed intolerance (RR 0.92, 95% CI 0.77 to 1.10, I2 = 0%, 8 trials, 1114 participants). Fast feed advancement may also reduce the risk of apnea (RR 0.72, 95% CI 0.47 to 1.12, I2 = 0%, low certainty, 2 trials, 153 participants). Fast feed advancement decreases time to regain birth weight (mean difference [MD] -3.69 days, 95% CI -4.44 to -2.95, I2 = 70%, high certainty, 6 trials, 993 participants,) and likely reduces the duration of hospitalization (MD -3.08 days, 95% CI -4.34 to -1.81, I2 = 77%, moderate certainty, 7 trials, 3864 participants). Limitations include heterogeneity between studies and small sample sizes.

CONCLUSIONS

Fast feed advancement reduces time to regain birth weight and likely reduces the length of hospital stay; it also likely reduces the risk of neonatal morbidity and mortality slightly. However, it may increase the risk of neurodevelopmental disability slightly. More studies are needed to understand the long-term effects of fast feed advancement.

Commentary on "compatibility of rapid enteral feeding advances and noninvasive ventilation in preterm infants-an observational study"

Nutritional support is essential in the critical care of the very preterm infant, however, the study of the potential role of nutrition in the multifactorial pathogenesis of bronchopulmonary dysplasia (BPD) is limited. Achievement of full enteral feeding faster has not been shown to be harmful and may be of benefit in extremely preterm infants. This commentary discusses the studied risk and potential benefits of more rapid enteral feeding advancement in extremely preterm infants.

Enteral Feeding Practices for Very Preterm and Very Low Birth Weight Infants in Nigeria and Kenya

Background

Optimizing nutrition in very preterm (28-32 weeks gestation) and very low birth weight (VLBW; 1,000 g to <1,500 g) infants has potential to improve their survival, growth, and long-term health outcomes.

Aim

To assess feeding practices in Nigeria and Kenya for very preterm and VLBW newborn infants.

Methods

This was a cross-sectional study where convenience sampling was used. A standard questionnaire was sent to doctors working in neonatal units in Nigeria and Kenya.

Results

Of 50 respondents, 37 (74.0%) were from Nigeria and 13 (26.0%) from Kenya. All initiated enteral feeds with breastmilk, with 24 (48.0%) initiating within 24 h. Only 28 (56.0%) used written feeding guidelines. Starting volumes ranged between 10 and 80 ml/kg/day. Median volume advancement of feeds was 20 ml/kg/day (IQR 10-20) with infants reaching full feeds in 8 days (IQR 6-12). 26 (52.0%) of the units fed the infants 2 hourly. Breastmilk fortification was practiced in 7 (14.0%) units, while folate, iron, calcium, and phosphorus were prescribed in 42 (84.0%), 36 (72.0%), 22 (44.0%), 5 (10.0%) of these units, respectively. No unit had access to donor breastmilk, and only 18 (36.0%) had storage facilities for expressed breastmilk. Twelve (24.0%) used wet nurses whilst 30 (60.0%) used formula feeds.

Conclusion

Feeding practices for very preterm and VLBW infants vary widely within Nigeria and Kenya, likely because of lack of locally generated evidence. High quality research that informs the feeding of these infants in the context of limited human resources, technology, and consumables, is urgently needed.

Slow advancement of enteral feed volumes to prevent necrotising enterocolitis in very low birth weight infants

BACKGROUND

Early enteral feeding practices are potentially modifiable risk factors for necrotising enterocolitis (NEC) in very preterm or very low birth weight (VLBW) infants. Observational studies suggest that conservative feeding regimens, including slowly advancing enteral feed volumes, reduce the risk of NEC. However, it is unclear whether slow feed advancement may delay establishment of full enteral feeding, and if it could be associated with infectious morbidities secondary to prolonged exposure to parenteral nutrition.

OBJECTIVES

To determine the effects of slow rates of enteral feed advancement on the risk of NEC, mortality, and other morbidities in very preterm or VLBW infants.

SEARCH METHODS

We searched CENTRAL (2020, Issue 10), Ovid MEDLINE (1946 to October 2020), Embase via Ovid (1974 to October 2020), Maternity and Infant Care database (MIDIRS) (1971 to October 2020), CINAHL (1982 to October 2020), and clinical trials databases and reference lists of retrieved articles for eligible trials.

SELECTION CRITERIA

We included randomised or quasi-randomised controlled trials that assessed effects of slow (up to 24 mL/kg/d) versus faster rates of advancement of enteral feed volumes on the risk of NEC in very preterm or VLBW infants.

DATA COLLECTION AND ANALYSIS

Two review authors separately evaluated trial risk of bias, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference. We used the GRADE approach to assess the certainty of evidence. Outcomes of interest were NEC, all-cause mortality, feed intolerance, and invasive infection.

MAIN RESULTS

We included 14 trials involving a total of 4033 infants (2804 infants participated in one large trial). None of the trials masked parents, caregivers, or investigators. Risk of bias was otherwise low. Most infants were stable very preterm or VLBW infants of birth weight appropriate for gestation. About one-third of all infants were extremely preterm or extremely low birth weight (ELBW), and about one-fifth were small for gestational age, growth-restricted, or compromised as indicated by absent or reversed end-diastolic flow velocity in the foetal umbilical artery. Trials typically defined slow advancement as daily increments of 15 to 24 mL/kg, and faster advancement as daily increments of 30 to 40 mL/kg. Meta-analyses showed that slow advancement of enteral feed volumes probably has little or no effect on the risk of NEC (RR 1.06, 95% confidence interval (CI) 0.83 to 1.37; RD 0.00, 95% CI -0.01 to 0.02; 14 trials, 4026 infants; moderate-certainty evidence) or all-cause mortality prior to hospital discharge (RR 1.13, 95% CI 0.91 to 1.39; RD 0.01, 95% CI -0.01 to 0.02; 13 trials, 3860 infants; moderate-certainty evidence). Meta-analyses suggested that slow advancement may slightly increase feed intolerance (RR 1.18, 95% CI 0.95 to 1.46; RD 0.05, 95% CI -0.02 to 0.12; 9 trials, 719 infants; low-certainty evidence) and may slightly increase the risk of invasive infection (RR 1.14, 95% CI 0.99 to 1.31; RD 0.02, 95% CI -0.00 to 0.05; 11 trials, 3583 infants; low-certainty evidence).

AUTHORS' CONCLUSIONS

The available trial data indicate that advancing enteral feed volumes slowly (daily increments up to 24 mL/kg) compared with faster rates probably does not reduce the risk of NEC, death, or feed intolerance in very preterm or VLBW infants. Advancing the volume of enteral feeds at a slow rate may slightly increase the risk of invasive infection.

Enteral Feeding Strategies in Preterm Neonates ≤32 weeks Gestational Age: A Systematic Review and Network Meta-Analysis

INTRODUCTION

Critical aspects of time of feed initiation, advancement, and volume of feed increment in preterm neonates remain largely unanswered.

METHODS

Medline , Embase, CENTRAL and CINAHL were searched from inception until 25th September 2020. Network meta-analysis with the Bayesian approach was used. Randomized controlled trials (RCTs) evaluating preterm neonates ≤32 weeks were included. Feeding regimens were divided based on the following categories: initiation day: early (<72 h), moderately early (72 h-7 days), and late (>7 days); advancement day: early (<72 h), moderately early (72 h-7 days), and late (>7 days); increment volume: small volume (SV) (<20 mL/kg/day), moderate volume (MoV) (20-< 30 mL/kg/day), and large volume (≥30 mL/kg/day); and full enteral feeding from the first day. Sixteen regimens were evaluated. Combined outcome of necrotizing enterocolitis (NEC) stage ≥ II or mortality before discharge was the primary outcome.

RESULTS

A total of 39 studies enrolled around 6,982 neonates. Early initiation (EI) with moderately early or late advancement using MoV increment enteral feeding regimens appeared to be most efficacious in decreasing the risk of NEC or mortality when compared to EI and early advancement with SV increment (risk ratio [95% credible interval]: 0.39 [0.12, 0.95]; 0.34 [0.10, 0.86]) (GRADE-very low).

CONCLUSIONS

Early initiated, moderately early, or late advanced with MoV increment feeding regimens might be most appropriate in decreasing the risk of NEC stage ≥II or mortality. In view of the certainty of evidence being very low, adequately powered RCTs evaluating these 2 strategies are warranted.

Two speeds of increasing milk feeds for very preterm or very low-birthweight infants: the SIFT RCT

BACKGROUND

Observational data suggest that slowly advancing enteral feeds in preterm infants may reduce necrotising enterocolitis but increase late-onset sepsis. The Speed of Increasing milk Feeds Trial (SIFT) compared two rates of feed advancement.

OBJECTIVE

To determine if faster (30 ml/kg/day) or slower (18 ml/kg/day) daily feed increments improve survival without moderate or severe disability and other morbidities in very preterm or very low-birthweight infants.

DESIGN

This was a multicentre, two-arm, parallel-group, randomised controlled trial. Randomisation was via a web-hosted minimisation algorithm. It was not possible to safely and completely blind caregivers and parents.

SETTING

The setting was 55 UK neonatal units, from May 2013 to June 2015.

PARTICIPANTS

The participants were infants born at < 32 weeks' gestation or a weight of < 1500 g, who were receiving < 30 ml/kg/day of milk at trial enrolment.

INTERVENTIONS

When clinicians were ready to start advancing feed volumes, the infant was randomised to receive daily feed increments of either 30 ml/kg/day or 18 ml/kg/day. In total, 1400 infants were allocated to fast feeds and 1404 infants were allocated to slow feeds.

MAIN OUTCOME MEASURES

The primary outcome was survival without moderate or severe neurodevelopmental disability at 24 months of age, corrected for gestational age. The secondary outcomes were mortality; moderate or severe neurodevelopmental disability at 24 months corrected for gestational age; death before discharge home; microbiologically confirmed or clinically suspected late-onset sepsis; necrotising enterocolitis (Bell's stage 2 or 3); time taken to reach full milk feeds (tolerating 150 ml/kg/day for 3 consecutive days); growth from birth to discharge; duration of parenteral feeding; time in intensive care; duration of hospital stay; diagnosis of cerebral palsy by a doctor or other health professional; and individual components of the definition of moderate or severe neurodevelopmental disability.

RESULTS

The results showed that survival without moderate or severe neurodevelopmental disability at 24 months occurred in 802 out of 1224 (65.5%) infants allocated to faster increments and 848 out of 1246 (68.1%) infants allocated to slower increments (adjusted risk ratio 0.96, 95% confidence interval 0.92 to 1.01). There was no significant difference between groups in the risk of the individual components of the primary outcome or in the important hospital outcomes: late-onset sepsis (adjusted risk ratio 0.96, 95% confidence interval 0.86 to 1.07) or necrotising enterocolitis (adjusted risk ratio 0.88, 95% confidence interval 0.68 to 1.16). Cost-consequence analysis showed that the faster feed increment rate was less costly but also less effective than the slower rate in terms of achieving the primary outcome, so was therefore found to not be cost-effective. Four unexpected serious adverse events were reported, two in each group. None was assessed as being causally related to the intervention.

LIMITATIONS

The study could not be blinded, so care may have been affected by knowledge of allocation. Although well powered for comparisons of all infants, subgroup comparisons were underpowered.

CONCLUSIONS

No clear advantage was identified for the important outcomes in very preterm or very low-birthweight infants when milk feeds were advanced in daily volume increments of 30 ml/kg/day or 18 ml/kg/day. In terms of future work, the interaction of different milk types with increments merits further examination, as may different increments in infants at the extremes of gestation or birthweight.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN76463425.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 18. See the NIHR Journals Library website for further project information.

Early enteral feeding in preterm infants

Early enteral feeding is a potentially modifiable risk factor for necrotising enterocolitis (NEC) and late onset sepsis (LOS), however enteral feeding practices for preterm infants are highly variable. High-quality evidence is increasingly available to guide early feeding in preterm infants. Meta-analyses of randomised trials indicate that early trophic feeding within 48 h after birth and introduction of progressive enteral feeding before 4 days of life at an advancement rate above 24 ml/kg/day can be achieved in clinically stable very preterm and very low birthweight (VLBW) infants, without higher mortality or incidence of NEC. This finding may not be generalisable to high risk infants such as those born small for gestational age (SGA) or following absent/reversed end diastolic flow velocity (AREDFV) detected antenatally on placental Doppler studies, due to the small number of such infants in existing trials. Trials targeting such high-risk preterm infants have demonstrated that progressive enteral feeding started in the first 4 days is safe and does not lead to higher NEC or mortality; however, there is a paucity of data to guide feeding advancement in such infants. There is little trial evidence to support bolus or continuous gavage feeding as being superior in clinically stable preterm infants. Trials that examine enteral feeding are commonly unblinded for technical and practical reasons, which increases the risk of bias in such trials, specifically when considering potentially subjective outcome such as NEC and LOS; future clinical trials should focus on objective, primary outcome measures such as all-cause mortality, long term growth and neurodevelopment. Alternatively, important short-term outcomes such as NEC could be used with blinded assessment.

Controlled Trial of Two Incremental Milk-Feeding Rates in Preterm Infants

BACKGROUND

Observational data have shown that slow advancement of enteral feeding volumes in preterm infants is associated with a reduced risk of necrotizing enterocolitis but an increased risk of late-onset sepsis. However, data from randomized trials are limited.

METHODS

We randomly assigned very preterm or very-low-birth-weight infants to daily milk increments of 30 ml per kilogram of body weight (faster increment) or 18 ml per kilogram (slower increment) until reaching full feeding volumes. The primary outcome was survival without moderate or severe neurodevelopmental disability at 24 months. Secondary outcomes included components of the primary outcome, confirmed or suspected late-onset sepsis, necrotizing enterocolitis, and cerebral palsy.

RESULTS

Among 2804 infants who underwent randomization, the primary outcome could be assessed in 1224 (87.4%) assigned to the faster increment and 1246 (88.7%) assigned to the slower increment. Survival without moderate or severe neurodevelopmental disability at 24 months occurred in 802 of 1224 infants (65.5%) assigned to the faster increment and 848 of 1246 (68.1%) assigned to the slower increment (adjusted risk ratio, 0.96; 95% confidence interval [CI], 0.92 to 1.01; P = 0.16). Late-onset sepsis occurred in 414 of 1389 infants (29.8%) in the faster-increment group and 434 of 1397 (31.1%) in the slower-increment group (adjusted risk ratio, 0.96; 95% CI, 0.86 to 1.07). Necrotizing enterocolitis occurred in 70 of 1394 infants (5.0%) in the faster-increment group and 78 of 1399 (5.6%) in the slower-increment group (adjusted risk ratio, 0.88; 95% CI, 0.68 to 1.16).

CONCLUSIONS

There was no significant difference in survival without moderate or severe neurodevelopmental disability at 24 months in very preterm or very-low-birth-weight infants with a strategy of advancing milk feeding volumes in daily increments of 30 ml per kilogram as compared with 18 ml per kilogram. (Funded by the Health Technology Assessment Programme of the National Institute for Health Research; SIFT Current Controlled Trials number, ISRCTN76463425.).