Continuous nasogastric milk feeding versus intermittent bolus milk feeding for premature infants less than 1500 grams

Continuous nasogastric milk feeding versus intermittent bolus milk feeding for preterm infants less than 1500 grams

BACKGROUND

Milk feedings can be given via nasogastric tube either intermittently, typically over 10 to 20 minutes every two or three hours, or continuously, using an infusion pump. Although the theoretical benefits and risks of each method have been proposed, their effects on clinically important outcomes remain uncertain.  OBJECTIVES: To examine the evidence regarding the effectiveness of continuous versus intermittent bolus tube feeding of milk in preterm infants less than 1500 grams.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to run comprehensive searches in the Cochrane Central Register of Controlled Trials (CENTRAL 2020, Issue 7) in the Cochrane Library; Ovid MEDLINE and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions; and CINAHL (Cumulative Index to Nursing and Allied Health Literature) on 17 July 2020. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs.

SELECTION CRITERIA

We included RCTs and quasi-RCTs comparing continuous versus intermittent bolus nasogastric milk feeding in preterm infants less than 1500 grams.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all trials for relevance and risk of bias. We used the standard methods of Cochrane Neonatal to extract data. We used the GRADE approach to assess the certainty of evidence. Primary outcomes were: age at full enteral feedings; feeding intolerance; days to regain birth weight; rate of gain in weight, length and head circumference; and risk of necrotising enterocolitis (NEC).

MAIN RESULTS

We included nine randomised trials (919 infants) in this updated Cochrane Review. One study is awaiting classification. Seven of the nine included trials reported data from infants with a maximum weight of between 1000 grams and 1400 grams. Two of the nine trials included infants weighing up to 1500 grams. Type(s) of milk feeds varied, including human milk (either mother's own milk or pasteurised donor human milk), preterm formula, or mixed feeding regimens. In some instances, preterm formula was initially diluted. Earlier studies also used water to initiate feedings. We judged six trials as unclear or high risk of bias for random sequence generation. We judged four trials as unclear for allocation concealment. We judged all trials as high risk of bias for blinding of care givers, and seven as unclear or high risk of bias for blinding of outcome assessors. We downgraded the certainty of evidence for imprecision, due to low numbers of participants in the trials, and/or wide 95% confidence intervals, and/or for risk of bias. Continuous compared to intermittent bolus (nasogastric and orogastric tube) milk feeding Babies receiving continuous feeding may reach full enteral feeding almost one day later than babies receiving intermittent feeding (mean difference (MD) 0.84 days, 95% confidence interval (CI) -0.13 to 1.81; 7 studies, 628 infants; low-certainty evidence).  It is uncertain if there is any difference between continuous feeding and intermittent feeding in terms of number of days of feeding interruptions (MD -3.00 days, 95% CI -9.50 to 3.50; 1 study, 171 infants; very low-certainty evidence). It is uncertain if continuous feeding has any effect on days to regain birth weight (MD -0.38 days, 95% CI -1.16 to 0.41; 6 studies, 610 infants; low-certainty evidence). The certainty of evidence is low and the 95% confidence interval is consistent with possible benefit and possible harm. It is uncertain if continuous feeding has any effect on rate of gain in weight compared with intermittent feeding (standardised mean difference (SMD) 0.09, 95% CI -0.27 to 0.46; 5 studies, 433 infants; very low-certainty evidence). Continuous feeding may result in little to no difference in rate of gain in length compared with intermittent feeding (MD 0.02 cm/week, 95% CI -0.04 to 0.08; 5 studies, 433 infants; low-certainty evidence). Continuous feeding may result in little to no difference in rate of gain in head circumference compared with intermittent feeding (MD 0.01 cm/week, 95% CI -0.03 to 0.05; 5 studies, 433 infants; low-certainty evidence). It is uncertain if continuous feeding has any effect on the risk of NEC compared with intermittent feeding (RR 1.19, 95% CI 0.67 to 2.11; 4 studies, 372 infants; low-certainty evidence). The certainty of evidence is low and the 95% confidence interval is consistent with possible benefit and possible harm.

AUTHORS' CONCLUSIONS

Although babies receiving continuous feeding may reach full enteral feeding slightly later than babies receiving intermittent feeding, the evidence is of low certainty. However, the clinical risks and benefits of continuous and intermittent nasogastric tube milk feeding cannot be reliably discerned from current available randomised trials. Further research is needed to determine if either feeding method is more appropriate for the initiation of feeds. A rigorous methodology should be adopted, defining feeding protocols and feeding intolerance consistently for all infants. Infants should be stratified according to birth weight and gestation, and possibly according to illness.

Continuous feeding versus intermittent bolus feeding for premature infants with low birth weight: a meta-analysis of randomized controlled trials

Background/objectives

Clinical risks and advantages of both continuous feeding and intermittent feeding for preterm infants have been presented in previous studies. To determine the most appropriate feeding method for low-birth-weight infants, a meta-analysis was conducted.

Subjects/methods

Articles related to this topic were searched in PubMed, EMBASE, and Cochrane Library electronic database from the onset to May 2019. Heterogeneity analysis was performed with Chi-square and I² test. Pooled analysis was based on fixed effects model, if heterogeneity between the eligible studies was negligible (I² < 50%, P > 0.05). In contrast, a random effects model was carried out. The quality of including studies were evaluated by Cochrane assessment tool.

Results

A total of 1030 articles identified. Altogether, eight articles including 707 infants were included in final analysis based on eligibility criteria. In continuous feeding infants, time to achieving full feeds was longer (weight mean difference 0.98 (95% CI 0.26–1.71, P = 0.008) days) compared with intermittent feeding infants. Pooled analysis indicated there were no significant difference in other variables such as feeding intolerance, duration of hospitalization, days to regain birth weight, days to first successful oral feeding, duration of parenteral feeding, weight growth, length increment, head circumference growth, proven necrotizing enterocolitis, and probable necrotizing enterocolitis. In subgroup analysis for birth weight (<1000 g and >1000 g), we did not identify significant difference in time to full feeds, time to regain birth weight, and duration of hospitalization.

Conclusions

Intermittent feeding may be more beneficial for low-birth weight infants, However, well-designed studies and evidenced-based clinical practice are required to determine the most appropriate feeding method for premature infants with low birth weight.

Anabolic signaling and protein deposition are enhanced by intermittent compared with continuous feeding in skeletal muscle of neonates

Orogastric tube feeding is indicated for neonates with impaired ability to ingest and can be administered by intermittent bolus or continuous schedule. Our aim was to determine whether feeding modalities affect muscle protein deposition and to identify mechanisms involved. Neonatal pigs were overnight fasted (FAS) or fed the same amount of food continuously (CON) or intermittently (INT; 7 × 4 h meals) for 29 h. For 8 h, between hours 20 and 28, pigs were infused with [(2)H(5)]phenylalanine and [(2)H(2)]tyrosine, and amino acid (AA) net balances were measured across the hindquarters. Insulin, branched-chain AA, phenylalanine, and tyrosine arterial concentrations and whole body phenylalanine and tyrosine fluxes were greater for INT after the meal than for CON or FAS. The activation of signaling proteins leading to initiation of mRNA translation, including eukaryotic initiation factor (eIF)4E·eIF4G complex formation in muscle, was enhanced by INT compared with CON feeding or FAS. Signaling proteins of protein degradation were not affected by feeding modalities except for microtubule-associated protein light chain 3-II, which was highest in the FAS. Across the hindquarters, AA net removal increased for INT but not for CON or FAS, with protein deposition greater for INT. This was because protein synthesis increased following feeding for INT but remained unchanged for CON and FAS, whereas there was no change in protein degradation across any dietary treatment. These results suggest that muscle protein accretion in neonates is enhanced with intermittent bolus to a greater extent than continuous feeding, mainly by increased protein synthesis.

Gastric lactobezoar - a rare disorder?

Gastric lactobezoar, a pathological conglomeration of milk and mucus in the stomach of milk-fed infants often causing gastric outlet obstruction, is a rarely reported disorder (96 cases since its first description in 1959). While most patients were described 1975-1985 only 26 children have been published since 1986. Clinically, gastric lactobezoars frequently manifest as acute abdomen with abdominal distension (61.0% of 96 patients), vomiting (54.2%), diarrhea (21.9%), and/or a palpable abdominal mass (19.8%). Respiratory (23.0%) and cardiocirculatory (16.7%) symptoms are not uncommon. The pathogenesis of lactobezoar formation is multifactorial: exogenous influences such as high casein content (54.2%), medium chain triglycerides (54.2%) or enhanced caloric density (65.6%) of infant milk as well as endogenous factors including immature gastrointestinal functions (66.0%), dehydration (27.5%) and many other mechanisms have been suggested. Diagnosis is easy if the potential presence of a gastric lactobezoar is thought of, and is based on a history of inappropriate milk feeding, signs of acute abdomen and characteristic features of diagnostic imaging. Previously, plain and/or air-, clear fluid- or opaque contrast medium radiography techniques were used to demonstrate a mass free-floating in the lumen of the stomach. This feature differentiates a gastric lactobezoar from intussusception or an abdominal neoplasm. Currently, abdominal ultrasound, showing highly echogenic intrabezoaric air trapping, is the diagnostic method of choice. However, identifying a gastric lactobezoar requires an investigator experienced in gastrointestinal problems of infancy as can be appreciated from the results of our review which show that in not even a single patient gastric lactobezoar was initially considered as a possible differential diagnosis. Furthermore, in over 30% of plain radiographs reported, diagnosis was initially missed although a lactobezoar was clearly demonstrable on repeat evaluation of the same X-ray films. Enhanced diagnostic sensitivity would be most rewarding since management consisting of cessation of oral feedings combined with administration of intravenous fluids and gastric lavage is easy and resolves over 85% of gastric lactobezoars. In conclusion, gastric lactobezoar is a disorder of unknown prevalence and is nowadays very rarely published, possibly because of inadequate diagnostic sensitivity and/or not yet identified but beneficial modifications of patient management.

Continuous nasogastric milk feeding versus intermittent bolus milk feeding for premature infants less than 1500 grams

BACKGROUND

Milk feedings can be given via nasogastric tube either intermittently, typically over 10 to 20 minutes every two or three hours, or continuously, using an infusion pump. Although theoretical benefits and risks of each method have been proposed, effects on clinically important outcomes remain uncertain.

OBJECTIVES

To examine the evidence regarding the effectiveness of continuous versus intermittent bolus nasogastric milk feeding in premature infants less than 1500 grams.

SEARCH METHODS

Searches were performed of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3, 2011), MEDLINE, CINAHL and HealthSTAR up to July 2011.

SELECTION CRITERIA

Randomised and quasi-randomised clinical trials comparing continuous versus intermittent bolus nasogastric milk feeding in premature infants less than 1500 grams.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all trials for relevance and methodologic quality. The standard methods of the Cochrane Neonatal Review Group were used to extract data.

MAIN RESULTS

Overall, the seven included trials, involving 511 infants, found no differences in time to achieve full enteral feeds between feeding methods (weighted mean difference (WMD) 2 days; 95% CI -0.3 to 3.9) . In the subgroup analysis of those studies comparing continuous nasogastric versus intermittent bolus nasogastric milk feedings the findings remained unchanged (WMD 2 days, 95% CI -0.4 to 4.1). There was no significant difference in somatic growth and incidence of NEC between feeding methods irrespective of tube placement. One study noted a trend toward more apneas during the study period in infants fed by the continuous tube feeding method compared to those fed by intermittent feedings delivered predominantly by orogastric tube placements [mean difference (MD) 14.0 apneas during study period; 95% CI -0.2 to 28.2]. In subgroup analysis based on weight groups, one study suggested that infants less than 1000 grams and 1000 to 1250 grams birth weight gained weight faster when fed by the continuous nasogastric tube feeding method compared to intermittent nasogastric tube feeding method (MD 2.0 g/day; 95% CI 0.5 to 3.5; MD 2.0 g/day; 95% CI 0.2 to 3.8, respectively). A trend toward earlier discharge for infants less than 1000 grams birth weight fed by the continuous tube feeding method compared to intermittent nasogastric tube feeding method (MD -11 days; 95% CI -21.8 to -0.2).

AUTHORS' CONCLUSIONS

Small sample sizes, methodologic limitations, inconsistencies in controlling variables that may affect outcomes, and conflicting results of the studies to date make it difficult to make universal recommendations regarding the best tube feeding method for premature infants less than 1500 grams. The clinical benefits and risks of continuous versus intermittent nasogastric tube milk feeding cannot be reliably discerned from the limited information available from randomised trials to date.

An update on necrotizing enterocolitis: pathogenesis and preventive strategies

Necrotizing enterocolitis (NEC) is one of the most critical morbidities in preterm infants. The incidence of NEC is 7% in very-low-birth-weight infants, and its mortality is 15 to 30%. Infants who survive NEC have various complications, such as nosocomial infection, malnutrition, growth failure, bronchopulmonary dysplasia, retinopathy of prematurity, and neurodevelopmental delays. The most important etiology in the pathogenesis of NEC is structural and immunological intestinal immaturity. In preterm infants with immature gastrointestinal tracts, development of NEC may be associated with a variety of factors, such as colonization with pathogenic bacteria, secondary ischemia, genetic polymorphisms conferring NEC susceptibility, anemia with red blood cell transfusion, and sensitization to cow milk proteins. To date, a variety of preventive strategies has been accepted or attempted in clinical practice with regard to the pathogenesis of NEC. These strategies include the use of breast feeding, various feeding strategies, probiotics, prebiotics, glutamine and arginine, and lactoferrin. There is substantial evidence for the efficacy of breast feeding and the use of probiotics in infants with birth weights above 1,000 g, and these strategies are commonly used in clinical practice. Other preventive strategies, however, require further research to establish their effect on NEC.

Continuous feedings of fortified human milk lead to nutrient losses of fat, calcium and phosphorous

Substantial losses of nutrients may occur during tube (gavage) feeding of fortified human milk. Our objective was to compare the losses of key macronutrients and minerals based on method of fortification and gavage feeding method. We used clinically available gavage feeding systems and measured pre- and post-feeding (end-point) nutrient content of calcium (Ca), phosphorus (Phos), protein, and fat. Comparisons were made between continuous, gravity bolus, and 30-minute infusion pump feeding systems, as well as human milk fortified with donor human milk-based and bovine milk-based human milk fortifier using an in vitro model. Feeding method was significantly associated with fat and Ca losses, with increased losses in continuous feeds. Fat losses in continuous feeds were substantial, with 40 ± 3 % of initial fat lost during the feeding process. After correction for feeding method, human milk fortified with donor milk-based fortifier was associated with significantly less loss of Ca (8 ± 4% vs. 28 ± 4%, p< 0.001), Phos (3 ± 4% vs. 24 ± 4%, p < 0.001), and fat (17 ± 2% vs. 25 ± 2%, p = 0.001) than human milk fortified with a bovine milk-based fortifier (Mean ± SEM).

Human milk consumption and full enteral feeding among infants who weigh </= 1250 grams

OBJECTIVE

Establishing enteral feeding is an important goal in the care of very low birth weight infants. In such infants, receipt of >/=50 mL/kg per day human milk during hospitalization has been associated with shorter time to full enteral feeding. The objective of this study was to determine whether high proportions (>/=50%) of human milk during feeding advancement are associated with shorter time to full enteral feeding and improved feeding tolerance.

METHODS

This was a prospective cohort study of very low birth weight infants (n = 127) who were grouped into low (<50%; n = 34) and high (>/=50%; n = 93) human milk consumption groups according to their human milk proportion of enteral feeding during the time of feeding advancement. The primary outcomes of interest were ages at which 100 and 150 mL/kg per day enteral feedings were achieved.

RESULTS

The high human milk group reached 100 mL/kg per day enteral feeding 4.5 days faster than the low human milk group. The high human milk group reached 150 mL/kg per day enteral feeding 5 days faster than the low human milk group. After adjustment for gestational age, gender, and respiratory distress syndrome, times to reach 100 and 150 mL/kg per day were significantly shorter for those in the high human milk group. Infants in the high human milk group had a greater number of stools per day; other indicators of feeding tolerance were not statistically different.

CONCLUSION

In infants who weighed </=1250 g, enteral feeding that contained at least 50% maternal human milk was associated with fewer days to full enteral feedings.

Feeding of low birth weight infants

Optimal feeding of low birth weight (LBW) infants improves their immediate survival and subsequent growth and development. Being a heterogeneous group comprising term and preterm neonates, their feeding abilities, fluid and nutritional requirements are quite different from normal birth weight infants. A practical approach to feeding a LBW infant including choice of initial feeding method, progression of oral feeds, and nutritional supplementation based on her oral feeding skills and nutritional requirements is being discussed in this protocol. Growth monitoring, management of feed intolerance, and the essential skills involved in feeding them have also been described in detail.

Transpyloric versus gastric tube feeding for preterm infants

BACKGROUND

Enteral feeding tubes for preterm infants may be placed in the stomach (gastric tube feeding) or in the upper small bowel (transpyloric tube feeding). There are potential advantages and disadvantages to both routes.

OBJECTIVES

To determine the effect of feeding via the transpyloric route versus feeding via the gastric route on feeding tolerance, growth and development and adverse consequences in preterm infants who require enteral tube feeding.

SEARCH STRATEGY

The standard search strategy of the Cochrane Neonatal Review Group was used. This included electronic searches of MEDLINE and EMBASE (up to March 2007) and of The Cochrane Controlled Trials Register in The Cochrane Library (Issue 1, 2007), and searches of the references in previous reviews including cross references.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials comparing transpyloric with gastric tube feeding in preterm infants.

DATA COLLECTION AND ANALYSIS

Data were extracted using the standard methods of the Cochrane Neonatal Review Group, with separate evaluation of trial quality and data extraction by each author and synthesis of data using relative risk (RR) and weighted mean difference (WMD).

MAIN RESULTS

Data from nine trials were available. No evidence of an effect on short term growth rates was found: weight: WMD -0.7 g/week (95% confidence interval (CI) -25.2, 23.8); crown heel length: WMD -0.7 mm/week (95% CI -2.4, 1.0); head circumference: WMD 0.6 mm/week (95% CI -0.9, 2.1). Longer term growth was reported in one study. There were not any statistically significant differences between the groups in the mean body weight or occipitofrontal head circumference at three months or at six months corrected age. None of the included studies provided data on neurodevelopmental outcomes. Transpyloric feeding was associated with a greater incidence of gastro-intestinal disturbance (RR 1.45, 95% CI 1.05, 2.09). There was some evidence that feeding via the transpyloric route increased mortality (RR 2.46, 95% CI 1.36, 4.46). However, the outcomes of the study that contributed most to this finding were likely to have been affected by selective allocation of the less mature and sicker infants to transpyloric feeding. No statistically significant differences in the incidence of other adverse events, including necrotising enterocolitis, intestinal perforation, and aspiration pneumonia was found.

AUTHORS' CONCLUSIONS

No evidence of any beneficial effect of transpyloric feeding in preterm infants was found. However, evidence of adverse effects was noted. Feeding via the transpyloric route cannot be recommended for preterm infants.

Prevention of necrotizing enterocolitis in preterm infants: a 20-year experience

OBJECTIVE

Diet, indomethacin, and early use of dexamethasone have been implicated as possible causes of necrotizing enterocolitis and intestinal perforation. Because we seldom prescribe indomethacin or early dexamethasone therapy and we follow a special dietary regimen that provides late-onset, slow, continuous drip enteral feeding, we reviewed our 20 years of experience for the incidence of necrotizing enterocolitis and bowel perforation.

METHODS

We reviewed data on all 1239 very low birth weight infants (501-1500 g) admitted to our level III unit over a period of 20 years (1986-2005), for morphologic parameters, necrotizing enterocolitis, bowel perforation, use of the late-onset, slow, continuous drip protocol, and indomethacin therapy. Outcome data were also compared with Vermont Oxford Network data for the last 4 years.

RESULTS

In 20 years, 1158 infants received the late-onset, slow, continuous drip feeding protocol (group I), whereas 81 infants had either a change in dietary regimen, use of indomethacin, or early use of dexamethasone (group II). The rate of necrotizing enterocolitis in group I of 0.4% was significantly lower than that in group II of 6%. Group I, in comparison with the Vermont Oxford Network, had significantly lower rates of necrotizing enterocolitis (0.4% vs 5.9%), surgical necrotizing enterocolitis (0.4% vs 3.1%), and bowel perforation (0.35% vs 2.2%).

CONCLUSIONS

Our 20-year experience with 1239 very low birth weight infants suggests strongly that the late-onset, slow, continuous drip feeding protocol and avoidance of indomethacin and early dexamethasone treatment contribute to the prevention of necrotizing enterocolitis.

Early enteral feeding for the very low birth weight infant: the development and impact of a research-based guideline

Providing optimal nutrition for the very low birth weight (VLBW) infant is critical during the neonatal period. Evidence-based practice guidelines are essential in managing these fragile infants. Putting scientific research into daily clinical practice may be arduous at times, however. A multidisciplinary team of health care providers successfully established a practical feeding guideline for a 52-bed, teaching-affiliated, Level III neonatal intensive care unit in St. Louis. This guideline identifies human milk as the recommended source of nutrition for the VLBW infant, a suggestion that has significantly affected lactation services in the unit. This article describes the process of developing, implementing, and evaluating a feeding guideline based on current research and describes the impact on lactation rates of having such a guideline in place within the unit.

New perspectives on nutrition enhance outcomes for premature infants

Significant advances have occurred during the past 20 years in the understanding of the complex relationships of the environment, the developing gut-associated immune system, the bacterial flora, the barrier functions of the gut, and the effects of nutrient intake. These advances have produced a profoundly different way of interpreting the nutritional requirements for normal growth and development of premature infants throughout their entire life.

Feeding the ill or preterm infant

Illness and immaturity often interfere with a neonate's ability to receive full enteral feedings during the first week of life. The goals of feeding in the NICU are to nourish the preterm infant for appropriate growth and development and to facilitate the earliest possible discharge from the NICU. Early, small-volume feedings, or trophic feedings, have been studied as a method for achieving these goals. The high-risk infant given such trophic feedings not only receives minimum enteral nutrition, but also attains earlier full nutritional feedings and, consequently, is discharged home earlier. Oro- or nasal-gastric gavage feedings are usually indicated for this group of infants because of their physiologic immaturity and the frequent presence of respiratory illness. Recent studies support the use of intermittent bolus feedings, which have long been used for the premature infant. Several authors have noted advantages to continuous infusions as well. Because the infant is unable to pace or refuse gavage feedings, the caretaker must determine the appropriate volume of each feeding. The optimal volume for initiation and advancement of trophic and nutritional feedings is still under investigation, but reports have demonstrated safe volumes for even the extremely premature infant.