Abdominal circumference or gastric residual volume as measure of feed intolerance in VLBW infants

Nutritional Strategies for Preterm Neonates and Preterm Neonates Undergoing Surgery: New Insights for Practice and Wrong Beliefs to Uproot

The nutrition of preterm infants remains contaminated by wrong beliefs that reflect inexactitudes and perpetuate old practices. In this narrative review, we report current evidence in preterm neonates and in preterm neonates undergoing surgery. Convictions that necrotizing enterocolitis is reduced by the delay in introducing enteral feeding, a slow advancement in enteral feeds, and the systematic control of residual gastric volumes, should be abandoned. On the contrary, these practices prolong the time to reach full enteral feeding. The length of parenteral nutrition should be as short as possible to reduce the infectious risk. Intrauterine growth restriction, hemodynamic and respiratory instability, and patent ductus arteriosus should be considered in advancing enteral feeds, but they must not translate into prolonged fasting, which can be equally dangerous. Clinicians should also keep in mind the risk of refeeding syndrome in case of high amino acid intake and inadequate electrolyte supply, closely monitoring them. Conversely, when preterm infants undergo surgery, nutritional strategies are still based on retrospective studies and opinions rather than on randomized controlled trials. Finally, this review also highlights how the use of adequately fortified human milk is strongly recommended, as it offers unique benefits for immune and gastrointestinal health and neurodevelopmental outcomes.

Routine versus no assessment of gastric residual volumes in preterm infants receiving enteral feeding via intermittent feeding tubes: a randomized controlled trial

OBJECTIVE

To evaluate whether eliminating routine gastric residual volume (GRV) assessments would lead to quicker attainment of full feeding volumes in preterm infants.

STUDY DESIGN

This is a prospective randomized controlled trial of infants ≤32 weeks gestation and birthweight ≤1250 g admitted to a tertiary care NICU. Infants were randomized to assess or not assess GRV before enteral tube feedings. The primary outcome was time to attain full enteral feeding volume defined as 120 ml/kg/day. The Wilcoxon rank sum test was used to compare the days to reach full enteral feeds between the two groups.

RESULTS

80 infants were randomized, 39 to the GRV assessing and 41 to the No-GRV assessing group. A predetermined interim analysis at 50% enrollment showed no difference in primary outcome and the study was stopped as recommended by the Data Safety Monitoring Committee. There was no significant difference in median days to reach full enteral feeds between the two groups [GRV assessment: 12d (5) vs. No-GRV assessment:13d (9)]. There was no mortality in either group, one infant in each group developed necrotizing enterocolitis stage 2 or greater.

CONCLUSION

Eliminating the practice of gastric residual volume assessment before feeding did not result in shorter time to attain full feeding.

Re-feeding versus discarding gastric residuals to improve growth in preterm infants

BACKGROUND

Routine monitoring of gastric residuals in preterm infants on tube feeds is a common practice in neonatal intensive care units used to guide initiation and advancement of enteral feeding. There is a paucity of consensus on whether to re-feed or discard the aspirated gastric residuals. While re-feeding gastric residuals may aid in digestion and promote gastrointestinal motility and maturation by replacing partially digested milk, gastrointestinal enzymes, hormones, and trophic substances, abnormal residuals may result in vomiting, necrotising enterocolitis, or sepsis.

OBJECTIVES

To assess the efficacy and safety of re-feeding when compared to discarding gastric residuals in preterm infants.  SEARCH METHODS: Searches were conducted in February 2022 in Cochrane CENTRAL via CRS, Ovid MEDLINE and Embase, and CINAHL. We also searched clinical trial databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs.

SELECTION CRITERIA

We selected RCTs that compared re-feeding versus discarding gastric residuals in preterm infants.

DATA COLLECTION AND ANALYSIS

Review authors assessed trial eligibility and risk of bias and extracted data, in duplicate. We analysed treatment effects in individual trials and reported the risk ratio (RR) for dichotomous data and the mean difference (MD) for continuous data, with respective 95% confidence intervals (CIs). We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We found one eligible trial that included 72 preterm infants. The trial was unmasked but was otherwise of good methodological quality. Re-feeding gastric residual may have little or no effect on time to regain birth weight (MD 0.40 days, 95% CI -2.89 to 3.69; 59 infants; low-certainty evidence), risk of necrotising enterocolitis stage ≥ 2 or spontaneous intestinal perforation (RR 0.71, 95% CI 0.25 to 2.04; 72 infants; low-certainty evidence), all-cause mortality before hospital discharge (RR 0.50, 95% CI 0.14 to 1.85; 72 infants; low-certainty evidence), time to establish enteral feeds ≥ 120 mL/kg/d (MD -1.30 days, 95% CI -2.93 to 0.33; 59 infants; low-certainty evidence), number of total parenteral nutrition days (MD -0.30 days, 95% CI -2.07 to 1.47; 59 infants; low-certainty evidence), and risk of extrauterine growth restriction at discharge (RR 1.29, 95% CI 0.38 to 4.34; 59 infants; low-certainty evidence). We are uncertain as to the effect of re-feeding gastric residual on number of episodes of feed interruption lasting for ≥ 12 hours (RR 0.80, 95% CI 0.42 to 1.52; 59 infants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

We found only limited data from one small unmasked trial on the efficacy and safety of re-feeding gastric residuals in preterm infants. Low-certainty evidence suggests re-feeding gastric residual may have little or no effect on important clinical outcomes such as necrotising enterocolitis, all-cause mortality before hospital discharge, time to establish enteral feeds, number of total parenteral nutrition days, and in-hospital weight gain. A large RCT is needed to assess the efficacy and safety of re-feeding of gastric residuals in preterm infants with adequate certainty of evidence to inform policy and practice.

Routine monitoring of gastric residual for prevention of necrotising enterocolitis in preterm infants

BACKGROUND

Routine monitoring of gastric residual in preterm infants on gavage feeds is a common practice used to guide initiation and advancement of feeds. It is believed that an increase in or an altered gastric residual may be predictive of necrotising enterocolitis (NEC). Withholding monitoring of gastric residual may take away the early indicator and thus may increase the risk of NEC. However, routine monitoring of gastric residual as a guide, in the absence of uniform standards, may lead to unnecessary delay in initiation and advancement of feeds and hence might result in a delay in establishing full enteral feeds. This in turn may increase the duration of total parenteral nutrition (TPN) and central venous line usage, increasing the risk of associated complications. Furthermore, delays in establishing full enteral feeds increase the risk of extrauterine growth restriction and neurodevelopmental impairment.

OBJECTIVES

• To assess the efficacy and safety of routine monitoring versus no monitoring of gastric residual in preterm infants • To assess the efficacy and safety of routine monitoring of gastric residual based on two different criteria for interrupting feeds or decreasing feed volume in preterm infants SEARCH METHODS: We conducted searches in Cochrane CENTRAL via CRS, Ovid MEDLINE, Embase and CINAHL in February 2022. We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials (RCTs), quasi- and cluster-RCTs.

SELECTION CRITERIA

We selected RCTs that compared routine monitoring versus no monitoring of gastric residual and trials that used two different criteria for gastric residual to interrupt feeds in preterm infants.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, risk of bias and extracted data. We analysed treatment effects in individual trials and reported risk ratio (RR) for dichotomous data, and mean difference (MD) for continuous data, with respective 95% confidence intervals (CI). We calculated the number needed to treat for an additional beneficial/harmful outcome (NNTB/NNTH) for dichotomous outcomes with significant results. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included five studies (423 infants) in this updated review. Routine monitoring versus no routine monitoring of gastric residual in preterm infants Four RCTs with 336 preterm infants met the inclusion criteria for this comparison. Three studies were performed in infants with birth weight of < 1500 g, while one study included infants with birth weight between 750 g and 2000 g. The trials were unmasked but were otherwise of good methodological quality. Routine monitoring of gastric residual:  - probably has little or no effect on the risk of NEC (RR 1.08, 95% CI 0.46 to 2.57; 334 participants, 4 studies; moderate-certainty evidence); - probably increases the time to establish full enteral feeds (MD 3.14 days, 95% CI 1.93 to 4.36; 334 participants, 4 studies; moderate-certainty evidence); - may increase the time to regain birth weight (MD 1.70 days, 95% CI 0.01 to 3.39; 80 participants, 1 study; low-certainty evidence);  - may increase the number of infants with feed interruption episodes (RR 2.21, 95% CI 1.53 to 3.20; NNTH 3, 95% CI 2 to 5; 191 participants, 3 studies; low-certainty evidence);  - probably increases the number of TPN days (MD 2.57 days, 95% CI 1.20 to 3.95; 334 participants, 4 studies; moderate-certainty evidence); - probably increases the risk of invasive infection (RR 1.50, 95% CI 1.02 to 2.19; NNTH 10, 95% CI 5 to 100; 334 participants, 4 studies; moderate-certainty evidence); - may result in little or no difference in all-cause mortality before hospital discharge (RR 2.14, 95% CI 0.77 to 5.97; 273 participants, 3 studies; low-certainty evidence). Quality and volume of gastric residual compared to quality of gastric residual alone for feed interruption in preterm infants One trial with 87 preterm infants met the inclusion criteria for this comparison. The trial included infants with 1500 g to 2000 g birth weight.  Using two different criteria of gastric residual for feed interruption: - may result in little or no difference in the incidence of NEC (RR 5.35, 95% CI 0.26 to 108.27; 87 participants; low-certainty evidence);  - may result in little or no difference in time to establish full enteral feeds (MD -0.10 days, 95% CI -0.91 to 0.71; 87 participants; low-certainty evidence); - may result in little or no difference in time to regain birth weight (MD 1.00 days, 95% CI -0.37 to 2.37; 87 participants; low-certainty evidence); - may result in little or no difference in number of TPN days (MD 0.80 days, 95% CI -0.78 to 2.38; 87 participants; low-certainty evidence); - may result in little or no difference in the risk of invasive infection (RR 5.35, 95% CI 0.26 to 108.27; 87 participants; low-certainty evidence); - may result in little or no difference in all-cause mortality before hospital discharge (RR 3.21, 95% CI 0.13 to 76.67; 87 participants; low-certainty evidence).  - we are uncertain about the effect of using two different criteria of gastric residual on the risk of feed interruption episodes (RR 3.21, 95% CI 0.13 to 76.67; 87 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Moderate-certainty evidence suggests routine monitoring of gastric residual has little or no effect on the incidence of NEC. Moderate-certainty evidence suggests monitoring gastric residual probably increases the time to establish full enteral feeds, the number of TPN days and the risk of invasive infection. Low-certainty evidence suggests monitoring gastric residual may increase the time to regain birth weight and the number of feed interruption episodes, and may have little or no effect on all-cause mortality before hospital discharge. Further RCTs are warranted to assess the effect on long-term growth and neurodevelopmental outcomes.

Impact of Routine Gastric Aspirate Monitoring on Very Low Birth Weight Early Preterm Infants

OBJECTIVES

Routine gastric aspirate (RGA) monitoring is a common yet controversial practice intended for early identification of gastrointestinal pathology in infants receiving gavage feeds. Our objectives were to evaluate the association of ceasing RGA monitoring on the incidence of necrotizing enterocolitis (NEC) as well as nutritional outcomes in a large population of very low birth weight (VLBW) and very preterm neonates.

METHODS

Retrospective record review of neonates born ≤32 weeks and/or VLBW from 2 cohorts: (1) during pre-feed RGA monitoring (September 2015 to June 2018) and (2) after cessation of RGA ("non-RGA") monitoring (July 2018 to December 2020). We compared incidence of NEC, time-to-full enteral feeds, central line duration, and duration of parenteral nutrition (PN) in bivariate and multivariable models accounting for changes in feeding protocols over time.

RESULTS

We identified 617 subjects, 53% in the RGA monitoring cohort (n = 327) and 47% in non-RGA cohort (n = 290). The non-RGA cohort had feeds initiated earlier ( P < 0.0001), achieved full enteral feeds more rapidly ( P < 0.0001), received a shorter duration of PN ( P = 0.0003), and had shorter central access duration ( P < 0.0001) without increasing NEC risk. In fact, the non-RGA cohort had a lower incidence of NEC ( P = 0.0345) compared to the RGA cohort. Even after adjusting for changes in feeding protocols over time in a multivariable model, the RGA cohort had significantly higher odds of NEC.

CONCLUSIONS

Pre-feed RGA monitoring in the absence of concerning clinical exam findings is not indicated for neonates receiving gavage feeds as it does not improve NEC incidence but instead may delay important nutritional outcomes such as feed initiation and central line removal.

Nurses' and Physicians' Rationale Behind Clinical Performance and Interpretation of Routine Prefeed Gastric Aspiration in Preterm Infants: A Cross-sectional Study

This study aims at understanding the rationale behind performing prefeed gastric aspirations in preterm infants, how nurses and physicians interpret the gastric aspiration and variations between them, and illuminating potential barriers for omitting routine prefeed aspiration. Nurses and physicians from all Danish neonatal intensive care units completed a questionnaire. Of 682 participants, the majority (94%) indicated that they routinely performed prefeed aspiration, primarily to check the feeding tube placement (nurses: 88%, physicians: 46%). Nurses feared necrotizing enterocolitis when observing a large gastric residual (GR) volume (31%) and green-stained GR (63%). Fewer nurses relative to physicians had "no worries" related to large volumes (15% vs 34%) or green-stained GR (14% vs 24%, both P < .01). More nurses than physicians intended to pause enteral feeding when observing green-stained GR (31% vs 16%, P < .01) and more nurses were concerned of completely omitting routine gastric aspirations (90% vs 46%, P < .05). The rationale behind the clinical use of GR volume and color as markers of necrotizing enterocolitis and feeding intolerance differs markedly between nurses and physicians in Denmark. If routine prefeed gastric aspiration should be omitted, special focus on information about early signs of necrotizing enterocolitis and methods to check tube placement is needed.

A systematic review of the definitions and prevalence of feeding intolerance in preterm infants

BACKGROUND & AIMS

Feeding intolerance (FI) is a common phenomenon experienced in preterm infants in neonatal intensive care units, as well as being a focus of many research studies into feeding methods, particularly in relation to comorbidities. There is no widely accepted definition of FI. This systematic review aimed to explore the range of definitions used for FI and provide an estimate of the prevalence amongst preterm infants.

METHODS

Searches were completed on MEDLINE (includes the Cochrane library), Embase, PsycInfo, CINAHL, NHS Evidence and Web of Science. Inclusion criteria; preterm infants in neonatal units, a clear definition of FI, >10 patients and be available in English language. Case reports were excluded.

RESULTS

One hundred studies were included. Definitions of FI were inconsistent. Studies were grouped according to definition used into: Group A - measuring gastric residual volume (GRV) only; group B - GRV and abdominal distension (AD); group C - GRV, AD and gastrointestinal symptoms (GI) which included any of vomiting, bilious vomiting and blood in stool; group D- GRV and GI; group E - AD and GI; group F - GI only and group G - any other elements used. Meta-analysis demonstrated that prevalence of FI between groups varied from 15 to 30% with an overall prevalence of 27% (95% confidence interval 23-31%). Group A had the highest prevalence. Review of time to full enteral feed was performed (37 studies) which demonstrated a range of 11.3-18.3 days depending on which FI definition used.

DISCUSSION

Definitions of FI in research are inconsistent, a similar finding to that seen in studies in both paediatric and adult critical care populations. The difficulty of defining FI in the preterm population is the concern regarding necrotising enterocolitis, with some studies using an overlap in their definitions, despite differing pathophysiology and management. Due to the heterogeneity of data obtained in this review regarding definitions used, further robust research is required in order to conclude which elements which should be used to define FI in this population.

PROSPERO NUMBER

CRD42019155596. Registered November 2019.

A Cross-sectional Survey of Enteral Feeding Tube Placement and Gastric Residual Aspiration Practices: Need for an Evidence-Based Clinical Practice Guideline

BACKGROUND

Preterm infants routinely require enteral feeding via nasogastric or orogastric tubes as an alternative to oral feeding to meet their nutritional needs. Anecdotal evidence suggests variations in practice related to correct tube placement and assessment of feed intolerance.

PURPOSE

To determine the current practices of enteral feeding tube placement confirmation and gastric residual (GR) aspiration of neonatal clinicians in Australia.

METHODS

A cross-sectional online survey comprising 24 questions was distributed to nursing and medical health professionals working in Australian neonatal care units through 2 e-mail listservs made available by professional organizations.

FINDINGS

The survey was completed by 129 clinicians. A single method was practiced by 50% of the clinicians in confirming tube placement, and most common practice was assessing the pH of GR aspirate. The majority of respondents (96%) reported that they relied on GR aspiration and clinical signs to determine feeding tolerance and subsequent decisions such as ceasing or decreasing feeds. However, the frequency of aspiration, the amount and color of aspirate considered to be normal/abnormal, and decisions on whether to replace gastric aspirate or whether aspiration should be performed during continuous tube feeding varied.

IMPLICATION FOR PRACTICE

This study demonstrated considerable variability in clinical practice for enteral feeding tube placement confirmation and GR aspiration despite most respondents reporting using a unit-based clinical practice guideline. Our study findings highlight the need for not only developing evidence-based practice guidelines for safe and consistent clinical practice but also ensuring that these guidelines are followed by all clinicians.

IMPLICATION FOR RESEARCH

Further research is needed to establish evidence-based methods both for enteral feeding tube placement confirmation and for the assessment of feeding intolerance during tube feeding. In addition, the reasons why evidence-based methods are not followed must be investigated.

Using a human-centred design approach to develop a comprehensive newborn monitoring chart for inpatient care in Kenya

Introduction

Job aids such as observation charts are commonly used to record inpatient nursing observations. For sick newborns, it is important to provide critical information, intervene, and tailor treatment to improve health outcomes, as countries work towards reducing neonatal mortality. However, inpatient vital sign readings are often poorly documented and little attention has been paid to the process of chart design as a method of improving care quality. Poorly designed charts do not meet user needs leading to increased mental effort, duplication, suboptimal documentation and fragmentation. We provide a detailed account of a process of designing a monitoring chart.

Methods

We used a Human-Centred Design (HCD) approach to co-design a newborn monitoring chart between March and May 2019 in three workshops attended by 16–21 participants each (nurses and doctors) drawn from 14 hospitals in Kenya. We used personas, user story mapping during the workshops and observed chart completion to identify challenges with current charts and design requirements. Two new charts were piloted in four hospitals between June 2019 and February 2020 and revised in a cyclical manner.

Results

Challenges were identified regarding the chart design and supply, and how staff used existing charts. Challenges to use included limited staffing, a knowledge deficit among junior staff, poor interprofessional communication, and lack of appropriate and working equipment. We identified a strong preference from participants for one chart to capture vital signs, assessment of the baby, and feed and fluid prescription and monitoring; data that were previously captured on several charts.

Discussion

Adopting a Human-Centred Design approach, we designed a new comprehensive newborn monitoring chart that is unlike observation charts in the literature that only focus on vital signs. While the new chart does not address all needs, we believe that once implemented, it can help build a clearer picture of the care given to newborns.

Conclusion

The chart was co-designed and piloted with the user and context in mind resulting in a unique monitoring chart that can be adopted in similar settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-07030-x.

Routine prefeed gastric aspiration in preterm infants: a systematic review and meta-analysis

Despite lack of evidence, the practice of routine prefeed gastric residue aspiration before the next feed is common. Recent studies suggest that this practice might be even harmful. Therefore, we aimed to evaluate the effect of avoiding routine prefeed gastric residue aspiration as compared to routine aspiration, on various clinical outcomes in preterm infants. We searched five different electronic databases (MEDLINE, EMBASE, Web of Science, CINAHL, and Cochrane Library) until March 8, 2021. Only randomized controlled trials comparing the practice of routine prefeed gastric aspiration with no routine aspiration in preterm infants were considered eligible. The random-effects meta-analysis was done using RevMan 5.3 software. Of the 894 unique records identified by our search, we included 6 studies (451 participants) in the review. There was no significant difference in the incidence of necrotizing enterocolitis (RR 0.80; 95% CI 0.31 to 2.08; 421 participants in 5 trials). Avoiding routine prefeed aspiration was associated with achieving full enteral feeds earlier (MD - 3.19 days, 95% CI - 4.22 to - 2.16), shorter duration of hospitalization (MD - 5.32 days; 95% CI - 10.25 to - 0.38), and lower incidence of late-onset sepsis (RR 0.77; 95% CI 0.60 to 0.99). Time to regain birth weight, days of total parenteral nutrition or central venous line usage, culture-positive sepsis, and all-cause mortality did not differ between the two groups.Conclusion: In the absence of other signs of feed intolerance, routine prefeed gastric residue aspiration should be avoided in preterm infants.Prospero registration number: CRD42020197657 What is Known: • Though, routine prefeed aspiration before next feed is a common practice in preterm gavage-fed infants. • Recent study suggests that the omission of routine gastric residual evaluation led to improved weight gain and earlier hospital discharge. What is New: • Low- to moderate-quality evidence suggest that avoiding routine prefeed gastric residue monitoring helps in the reduction of late-onset sepsis, achieving full enteral feeds earlier, and earlier discharge from the hospital. • Abandoning the practice of routine prefeed aspiration in absence of other signs of feed intolerance in preterm low birthweight neonates is safe.

Does selective evaluation of gastric aspirates in preterm infants influence time to full enteral feeding?

The use of routine gastric aspiration in the assessment of feeding intolerance is widespread in neonatal practice. Our article seeks to answer the clinical question, 'In premature infants receiving feeds via nasogastric or orogastric tube [P], does routine evaluation of gastric aspirates [I] compared with selective evaluation of gastric aspirates [C] reduce the time taken to establish full feeds without complications [O]?' Articles were identified through MEDLINE and reference lists from the sources found were reviewed for additional publications. Three papers were critically appraised and National Health and Medical Research Centre grades of level of evidence have been assigned to each. We found limited evidence to either support or reject the practice of routine gastric aspiration in preterm infants. There were no increases in the rates of significant complications in studies underpowered for this outcome. The decision to perform routine or selective gastric aspiration should be determined by individual centres. A large scale randomised controlled trial would be of significant benefit in determining the value of routine gastric aspiration in preterm infants.

Effect of Aspiration and Evaluation of Gastric Residuals on Intestinal Inflammation, Bleeding, and Gastrointestinal Peptide Level

OBJECTIVE

To determine the effect of gastric residual aspiration and evaluation on preterm very low birth weight infants' gastrointestinal function, intestinal inflammation, and gastrointestinal mucosal bleeding.

STUDY DESIGN

This single-center, randomized trial compared omission of gastric residuals vs prefeed gastric residuals in 143 infants ≤32 weeks of gestation with a birthweight of ≤1250 g for 6 weeks after birth. Serum levels of gastrin and motilin were collected between 14 and 21 days of life. Stools were collected at 3 and 6 weeks of age and analyzed for calprotectin and S100A12 levels. All stools were tested for occult blood for 6 weeks.

RESULTS

Means for gastrin (P = .999) and motilin (P = .694) were similar between groups and there were no statistically significant differences in adjusted means for transformed calprotectin (P = .580), and S100A12 (P = .212). Both calprotectin (P = .003) and S100A12 (P = .002) increased from week 3 to week 6. The mean percentage of stools positive for occult blood (P = .888) were similar between the groups.

CONCLUSIONS

Gastrointestinal function, intestinal inflammation, and gastrointestinal mucosal bleeding were similar whether aspiration and evaluation of gastric residuals were eliminated or not, suggesting routinely evaluating gastric residuals before every feeding may be unnecessary. TRIAL REGISTRATION CLINICALTRIALS.GOV:: NCT01863043.

Reference Values for Abdominal Circumference in Premature Infants

Objectives: Abdominal distention is a common indicator of feeding intolerance in premature newborns. In the absence of a precise definition, abdominal distention and its degree are highly subjective. The aim of this study was to construct references and smoothed percentiles for abdominal circumference (AC) and AC to head circumference (HC) ratio (AC/HC) in infants born between 24 weeks and 34 weeks of gestational age. Methods: ACs and HCs were collected weekly in eutrophic premature infants without congenital abdominal or cerebral malformation. AC and HC charts were modeled using the LMS method, excluding measures associated with abdominal distention at clinical examination or intracranial abnormality at cerebral ultrasounds. Changes in AC and AC/HC over time were studied by repeated-measures analysis using mixed-effects linear models. Results: A total of 1,605 measurements were made in 373 newborns with a mean gestational age of 31 [29-33] weeks and mean birth weight of 1,540 [1,160-1,968] g. Of these measurements, 1,220 were performed in normal conditions. Gestational age, postnatal age, singleton status, and respiratory support were significantly associated with AC and AC/HC. LMS curves were generated according to gestational age groups and postnatal age, with coherent profiles. AC/HC was 0.91 [0.86-0.95] in absence of abdominal distention. It was higher in cases of abdominal distention (0.95 [0.89-1.00], p < 0.001) and necrotizing enterocolitis (0.98 [0.93-1.07], p < 0.001). Conclusions: References constructed for AC and AC/HC might be used to assess feeding tolerance in premature infants. AC/HC was more relevant than AC to rationalize the diagnosis of abdominal distention.

Routine monitoring of gastric residual for prevention of necrotising enterocolitis in preterm infants

BACKGROUND

Routine monitoring of gastric residual in preterm infants on gavage feeds is a common practice that is used to guide initiation and advancement of feeds. Some literature suggests that an increase in/or an altered gastric residual may be predictive of necrotising enterocolitis. Withholding monitoring of gastric residual may take away the early indicator and thus may increase the risk of necrotising enterocolitis. However, routine monitoring of gastric residual as a guide, in the absence of uniform standards, may lead to unnecessary delay in initiation and advancement of feeds and delay in reaching full enteral feeds. This in turn may increase the duration of parenteral nutrition and central venous line usage, increasing their complications. Delay in achieving full enteral feeds increases the risk of extrauterine growth restriction and neurodevelopmental impairment.

OBJECTIVES

• To assess the efficacy and safety of routine monitoring of gastric residual versus no monitoring of gastric residual in preterm infants• To assess the efficacy and safety of routine monitoring of gastric residual based on two different criteria for interrupting feeds or decreasing feed volume in preterm infantsWe planned to undertake subgroup analysis based on gestational age (≤ 27 weeks, 28 weeks to 31 weeks, ≥ 32 weeks), birth weight (< 1000 g, 1000 g to 1499 g, ≥ 1500 g), small for gestational age versus appropriate for gestational age infants (classified using birth weight relative to the reference population), type of feed the infant is receiving (human milk or formula milk), and frequency of monitoring of gastric residual (before every feed, before every third feed, etc.) (see "Subgroup analysis and investigation of heterogeneity").

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 1), MEDLINE via PubMed (1966 to 19 February 2018), Embase (1980 to 19 February 2018), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 19 February 2018). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

We selected randomised and quasi-randomised controlled trials that compared routine monitoring of gastric residual versus no monitoring or two different criteria of gastric residual to interrupt feeds in preterm 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 the risk ratio and the risk difference for dichotomous data, and the mean difference for continuous data, with respective 95% confidence intervals. We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

Two randomised controlled trials with a total of 141 preterm infants met the inclusion criteria for the comparison of routine monitoring versus no monitoring of gastric residual in preterm infants. Both trials were done in infants with birth weight < 1500 g.Routine monitoring of gastric residual may have little or no effect on the incidence of necrotising enterocolitis (risk ratio (RR) 3.07, 95% confidence interval (CI) 0.50 to 18.77; participants = 141; studies = 2; low-quality evidence). Routine monitoring may increase the risk of feed interruption episodes (RR 2.07, 95% CI 1.39 to 3.07; participants = 141; studies = 2; low-quality evidence); the number needed to treat for an additional harmful outcome (NNTH) was 3 (95% CI 2 to 6).Routine monitoring of gastric residual may increase time taken to establish full enteral feeds (mean difference (MD) 3.92, 95% CI 2.06 to 5.77 days; participants = 141; studies = 2; low-quality evidence), time taken to regain birth weight (MD 1.70, 95% CI 0.01 to 3.39 days; participants = 80; studies = 1; low-quality evidence), and number of total parenteral nutrition days (MD 3.29, 95% CI 1.66 to 4.92 days; participants = 141; studies = 2; low-quality evidence).We are uncertain as to the effect of routine monitoring of gastric residual on other outcomes such as incidence of surgical necrotising enterocolitis, extrauterine growth restriction at discharge, parenteral nutrition-associated liver disease, duration of central venous line (CVL) usage, incidence of invasive infection, mortality before discharge, and duration of hospital stay. We found no data for outcomes such as aspiration pneumonia, gastroesophageal reflux, growth measures following discharge, and neurodevelopmental outcome.Only one trial with 87 preterm infants met the inclusion criteria for the comparison of using two different criteria of gastric residual to interrupt feeds while monitoring gastric residual. The trial was done in infants with birth weight of 1500 to 2000 g. We are uncertain as to the effect of using two different criteria of gastric residual on outcomes such as incidence of necrotising enterocolitis or surgical necrotising enterocolitis, time to establish full enteral feeds, time to regain birth weight, number of total parenteral nutrition days, number of infants experiencing feed interruption episodes, extrauterine growth restriction at discharge, parenteral nutrition-associated liver disease, incidence of invasive infection, and mortality before discharge (very low quality evidence). We found no data on duration of CVL usage, aspiration pneumonia, gastroesophageal reflux, duration of hospital stay, growth measures following discharge, and neurodevelopmental outcome.

AUTHORS' CONCLUSIONS

Review authors found insufficient evidence as to whether routine monitoring of gastric residual reduces the incidence of necrotising enterocolitis because trial results are imprecise. Low-quality evidence suggests that routine monitoring of gastric residual increases the risk of feed interruption episodes, increases the time taken to reach full enteral feeds and to regain birth weight, and increases the number of total parenteral nutrition (TPN) days.Available data are insufficient to comment on other major outcomes such as incidence of invasive infection, parenteral nutrition-associated liver disease, mortality before discharge, extrauterine growth restriction at discharge, number of CVL days, and duration of hospital stay. Further randomised controlled trials are warranted to provide more precise estimates of the effects of routine monitoring of gastric residual on important outcomes, especially necrotising enterocolitis, in preterm infants.

Re-feeding versus discarding gastric residuals to improve growth in preterm infants

BACKGROUND

Routine monitoring of gastric residuals in preterm infants on gavage feeds is a common practice in many neonatal intensive care units and is used to guide the initiation and advancement of feeds. No guidelines or consensus is available on whether to re-feed or discard the aspirated gastric residuals. Although re-feeding gastric residuals may replace partially digested milk, gastrointestinal enzymes, hormones, and trophic substances that aid in digestion and promote gastrointestinal motility and maturation, re-feeding abnormal residuals may result in emesis, necrotising enterocolitis, or sepsis.

OBJECTIVES

To assess the efficacy and safety of re-feeding compared to discarding gastric residuals in preterm infants. The allocation should have been started in the first week of life and should have been continued at least until the baby reached full enteral feeds. The investigator could have chosen to discard the gastric residual in the re-feeding group, if the gastric residual quality was not satisfactory. However, the criteria for discarding gastric residual should have been predefined.To conduct subgroup analysis based on gestational age (≤ 27 weeks, 28 weeks to 31 weeks, ≥ 32 weeks), birth weight (< 1000 g, 1000 g to 1499 g, ≥ 1500 g), type of milk (human milk or formula milk), quality of the gastric residual (fresh milk, curded milk, or bile-stained gastric residual), volume of gastric residual replaced (total volume, 50% of the volume, volume of the next feed, or prespecified volume, irrespective of the volume of the aspirate, e.g. 2 mL, 3 mL), and whether the volume of gastric residual that is re-fed is included in or excluded from the volume of the next feed (see "Subgroup analysis and investigation of heterogeneity").

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 1), MEDLINE via PubMed (1966 to 19 February 2018), Embase (1980 to 19 February 2018), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 19 February 2018). We also searched clinical trial databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials that compared re-feeding versus discarding gastric residuals in preterm 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 the risk ratio and risk difference for dichotomous data, and the mean difference for continuous data, with respective 95% confidence intervals. We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

We found one eligible trial that included 72 preterm infants. This trial was not blinded.We are uncertain as to the effect of re-feeding gastric residual on efficacy outcomes such as time to regain birth weight (mean difference (MD) 0.40 days, 95% confidence interval (CI) -2.89 to 3.69 days; very low quality evidence), time to reach enteral feeds ≥ 120 mL/kg/d (MD -1.30 days, 95% CI -2.93 to 0.33 days; very low quality evidence), number of infants with extrauterine growth restriction at discharge (risk ratio (RR) 1.29, 95% CI 0.38 to 4.34; very low quality evidence), duration of total parenteral nutrition (MD -0.30 days, 95% CI -2.07 to 1.47 days; very low quality evidence), and length of hospital stay (MD -1.90 days, 95% CI -25.27 to 21.47 days; very low quality evidence).Similarly, we are uncertain as to the effect of re-feeding gastric residual on safety outcomes such as incidence of stage 2 or 3 necrotising enterocolitis and/or spontaneous intestinal perforation (RR 0.71, 95% CI 0.25 to 2.04; very low quality evidence), number of episodes of feed interruption lasting ≥ 12 hours (RR 0.80, 95% CI 0.42 to 1.52; very low quality evidence), or mortality before discharge (RR 0.50, 95% CI 0.14 to 1.85; low-quality evidence). We are uncertain as to the effect of re-feeding gastric residual in the subgroups of human milk-fed and formula-fed infants. We found no data on other outcomes such as linear and head growth during hospital stay, postdischarge growth, number of infants with parenteral nutrition-associated liver disease, and neurodevelopmental outcomes.

AUTHORS' CONCLUSIONS

We found only limited data from one small unblinded trial on the efficacy and safety of re-feeding gastric residuals in preterm infants. The quality of evidence was low to very low. Hence, available evidence is insufficient to support or refute re-feeding of gastric residuals in preterm infants. A large, randomised controlled trial is needed to provide data of sufficient quality and precision to inform policy and practice.

Effect of Gastric Residual Evaluation on Enteral Intake in Extremely Preterm Infants: A Randomized Clinical Trial

IMPORTANCE

Evaluating prefeed gastric residuals is considered routine care but has little supporting evidence.

OBJECTIVE

To determine the effect of omitting prefeed gastric residual evaluation on nutritional outcomes in extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

This single-center randomized clinical trial compared the omission of gastric residual evaluation with prefeed gastric residual evaluation. Infants were recruited from a level 4 neonatal intensive care unit and were enrolled from October 17, 2013, to October 8, 2016, and then followed up for 6 weeks after birth. Eligible participants were infants born at 32 or fewer weeks' gestation with a birth weight of 1250 g or less; they were enrolled within 72 hours after birth and within 24 hours after feeding initiation. All participants (N = 143) were included in the modified intent-to-treat analysis, which was conducted from March to July 2018.

INTERVENTIONS

The residual group underwent prefeed gastric residual evaluation; the no residual group did not. Feeding decisions were made according to nutritional guidelines, and infants received only human milk.

MAIN OUTCOMES AND MEASURES

The primary outcome was weekly enteral nutrition intake in mL/kg for 6 weeks after birth.

RESULTS

Of 143 infants, 74 (51.7%) were randomized to undergo gastric residual evaluation (residual group) and 69 (48.3%) to omitted gastric residual evaluation (no residual group). The residual group comprised an even number of male and female infants (37 [50.0%]) with a mean (SD) gestational age of 27.1 (2.4) weeks and a mean (SD) birth weight of 888.8 (206.6) grams, whereas the no residual group had more male infants (36 [52.17%]), a mean (SD) gestational age of 27 (1.2) weeks, and a mean (SD) birth weight of 915.2 (180) grams. The no residual group had feedings that advanced more quickly compared with the residual group (mean weekly increase, 20.7 mL/kg/d vs 17.9 mL/kg/d; P = .02) and consumed more feedings at weeks 5 (137.2 [95% CI, 128.6-145.8]; P = .03) and 6 (141.6 [95% CI, 133.2-150.0]; P = .03). Among the secondary outcomes, the no residual group had higher mean estimated log weights (7.01 [95% CI, 6.99-7.02] vs 6.98 [95% CI, 6.97-7.00]; P = .03), had fewer episodes of abdominal distention (0.59 [95% CI, 0.34-1.01] vs 1.79 [95% CI, 1.27-2.53]; P = .001), and were discharged 8 days earlier (4.21 [95% CI, 4.14-4.28] vs 4.28 [95% CI, 4.19-4.36]; P = .01). Odds for necrotizing enterocolitis (0.058 [95% CI, 0.018-0.190] vs 0.026 [95% CI, 0.006-0.109]), death (0.004 [95% CI, 0.0003-0.046] vs 0.012 [95% CI, 0.001-0.131]), late-onset sepsis (0.970 [95% CI, 0.67-1.40] vs 1.38 [95% CI, 0.97-1.94]), and ventilator-associated pneumonia (0.084 [95% CI, 0.033-0.214] vs 0.056 [95% CI, 0.019-0.168]) were similar between groups.

CONCLUSIONS AND RELEVANCE

Among extremely preterm infants, the omission of gastric residual evaluation increased the delivery of enteral nutrition as well as improved weight gain and led to earlier hospital discharge; these results may translate into evidence-based practice.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01863043.

Enteral Nutrition Tolerance And REspiratory Support (ENTARES) Study in preterm infants: study protocol for a randomized controlled trial

Background

Respiratory distress syndrome (RDS) and feeding intolerance are common conditions in preterm infants and among the major causes of neonatal mortality and morbidity.

For many years, preterm infants with RDS have been treated with mechanical ventilation, increasing risks of acute lung injury and bronchopulmonary dysplasia.

In recent years non-invasive ventilation techniques have been developed. Showing similar efficacy and risk of bronchopulmonary dysplasia, nasal continuous positive airway pressure (NCPAP) and heated humidified high-flow nasal cannula (HHHFNC) have become the most widespread techniques in neonatal intensive care units. However, their impact on nutrition, particularly on feeding tolerance and risk of complications, is still unknown in preterm infants.

The aim of the study is to evaluate the impact of NCPAP vs HHHFNC on enteral feeding and to identify the most suitable technique for preterm infants with RDS.

Methods

A multicenter randomized single-blind controlled trial was designed. All preterm infants with a gestational age of 25–29 weeks treated with NCPAP or HHHFNC for RDS and demonstrating stability for at least 48 h along with the compliance with inclusion criteria (age less than 7 days, need for non-invasive respiratory support, suitability to start enteral feeding) will be enrolled in the study and randomized to the NCPAP or HHHFNC arm. All patients will be monitored until discharge, and data will be analyzed according to an intention-to-treat model.

The primary outcome is the time to reach full enteral feeding, while parameters of respiratory support, feeding tolerance, and overall health status will be evaluated as secondary outcomes. The sample size was calculated at 141 patients per arm.

Discussion

The identification of the most suitable technique (NCPAP vs HHHFNC) for preterm infants with feeding intolerance could reduce gastrointestinal complications, improve growth, and reduce hospital length of stay, thus improving clinical outcomes and reducing health costs. The evaluation of the timing of oral feeding could be useful in understanding the influence that these techniques could have on the development of sucking-swallow coordination. Moreover, the evaluation of the response to NCPAP and HHHFNC could clarify their efficacy as a treatment for RDS in extremely preterm infants.

Trial registration

ClinicalTrials.gov, NCT03548324. Registered on 7 June 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3119-0) contains supplementary material, which is available to authorized users.

Gastric Residual Volumes Versus Abdominal Girth Measurement in Assessment of Feed Tolerance in Preterm Neonates: A Randomized Controlled Trial

BACKGROUND

Preterm neonates often have feed intolerance that needs to be differentiated from necrotizing enterocolitis. Gastric residual volumes (GRV) are used to assess feed tolerance but with little scientific basis.

PURPOSE

To compare prefeed aspiration for GRV and prefeed measurement of abdominal girth (AG) in the time taken to reach full feeds in preterm infants.

METHODS

This was a randomized controlled trial. Infants with a gestational age of 27 to 37 weeks and birth weight of 750 to 2000 g, who required gavage feeds for at least 48 hours, were included. Infants were randomized into 2 groups: infants in the AG group had only prefeed AG measured. Those in the GRV group had prefeed gastric aspiration obtained for the assessment of GRV. The primary outcome was time to reach full enteral feeds at 150 mL/kg/d, tolerated for at least 24 hours. Secondary outcomes were duration of hospital stay, need for parenteral nutrition, episodes of feed intolerance, number of feeds withheld, and sepsis.

RESULTS

Infants in the AG group reached full feeds earlier than infants in the GRV group (6 vs 9.5 days; P = .04). No significant differences were found between the 2 groups with regard to secondary outcomes.

IMPLICATIONS FOR PRACTICE

Our research suggests that measurement of AG without assessment of GRV enables preterm neonates to reach full feeds faster than checking for GRV.

IMPLICATIONS FOR RESEARCH

Abdominal girth measurement as a marker for feed tolerance needs to be studied in infants less than 750 g and less than 26 weeks of gestation.

An anthropometric survey of US pre-term and full-term neonates

BACKGROUND

Anthropometric data prove valuable for screening and monitoring various medical conditions. In young infants, however, only weight, length and head circumference are represented in publicly accessible databases.

AIM

To characterise length and circumferential measures in pre-term and full-term infants up to 90 days post-natal.

SUBJECTS AND METHODS

In eight US medical centres, trained raters recorded humeral, ulnar, femoral, tibial and fibular lengths along with mid-upper arm, mid-thigh, chest, abdominal and neck circumference. Data were pooled by post-menstrual age into 1-week intervals and population curves created using the lambda, mu and sigma (LMS) method. Goodness-of-fit was assessed by examining de-trended quantile-quantile plots, Q statistics and fitted centiles overlaid on empirical centiles.

RESULTS

In total, 2097 infants were enrolled in this study with a mean ± SD gestational age and post-natal age of 37.1 ± 3.3 weeks and 27.3 ± 25.3 days, respectively. A re-scale option was used to describe all curves. The resultant models reliably characterised anthropometric measures from 33-52 weeks PMA, with less certainty at the extremes (27-55 weeks).

CONCLUSION

The population curves generated under this investigation expand existing reference data on a comprehensive set of anthropometric traits in infants through the first 90 days post-natal.

The Impact of Routine Evaluation of Gastric Residual Volumes on the Time to Achieve Full Enteral Feeding in Preterm Infants

OBJECTIVE

To evaluate the time to full enteral feedings in preterm infants after a practice change from routine evaluation of gastric residual volume before each feeding to selective evaluation of gastric residual volume , and to evaluate the impact of this change on the incidence of necrotizing enterocolitis (NEC).

STUDY DESIGN

Data were collected on all gavage-fed infants born at ≤34 weeks gestational age (GA) for 2 years before (n = 239) and 2 years after the change (n = 233).

RESULTS

The median GA was 32.0 (IQR: 29.7-33.0) weeks before and 32.4 (30.4-33.4) weeks after the change (P = .02). Compared with historic controls, infants with selective evaluations of gastric residual volumes weaned from parenteral nutrition 1 day earlier (P < .001) and achieved full enteral feedings (150 cc/kg/day) 1 day earlier (P = .002). The time to full oral feedings and lengths of stay were similar. The rate of NEC (stage ≥ 2) was 1.7% in the selective gastric residual volume evaluation group compared with 3.3% in the historic control group (P = .4). Multiple regression analyses showed that the strongest predictor of time to full enteral feedings was GA. Routine evaluation of gastric residual volume and increasing time on noninvasive ventilation both prolonged the attainment of full enteral feedings. Findings were consistent in the subgroup with birth weights of <1500 g. Increased weight at discharge was most strongly associated with advancing postmenstrual, age but avoidance of routine evaluations of gastric residual volume also was a significant factor.

CONCLUSIONS

Avoiding routine evaluation of gastric residual volume before every feeding was associated with earlier attainment of full enteral feedings without increasing risk for NEC.

The ConNECtion Between Abdominal Signs and Necrotizing Enterocolitis in Infants 501 to 1500 g

BACKGROUND

Necrotizing enterocolitis (NEC) can become severe quickly, making early recognition a priority and understanding the occurrence of abdominal and clinical signs of impending NEC important.

PURPOSE

The purpose of this study was to examine relationships of abdominal signs up to 36 hours before diagnosis of NEC within subgroups treated medically, surgically, or those who died.

METHODS

A 3-site, descriptive correlational case-control design with retrospective data collection was used matching each NEC case to 2 controls (N = 132).

RESULTS

NEC cases were exposed to less human milk and fed later. Among them, 61% (n = 27) had at least 1 abdominal sign 36 hours before diagnosis, with fewer numbers having 2 (18%; n = 8) or 3 (5%; n = 2). At 36 hours before NEC, abdominal distension, duskiness, higher gastric residual, and greater count of abdominal signs were associated with severe NEC. No medical NEC cases had abdominal signs 36 or 24 hours before diagnosis. Highest severity of NEC was related to more abdominal signs at the times leading up to and at diagnosis of NEC. Gastric residuals were largely unrelated to NEC except for the most severe NEC at 36 hours before diagnosis.

IMPLICATIONS FOR PRACTICE

Communicating a count of abdominal signs may support earlier recognition and treatment of NEC.

IMPLICATIONS FOR RESEARCH

More research is needed to explore timing for clinical worsening of status (eg, surgical and NEC leading to death) and to study effective clinical approaches targeting early recognition to support timely action.