Re-feeding versus discarding gastric residuals to improve growth 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 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 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.