Effect of Slow Versus Rapid Advancement of Enteral Feeding on Intestinal Oxygenation in Preterm Infants

TL;DR

This study found that rapid advancement of feeding in preterm infants increased intestinal oxygenation without increasing gastrointestinal risks, suggesting it could be a safe approach when monitored.

Contribution

The study introduces abdominal near-infrared spectroscopy as a non-invasive tool to monitor intestinal oxygenation during feeding in preterm infants.

Findings

Rapid feeding advancement led to greater increases in intestinal oxygenation compared to slow advancement.

No significant difference in gastrointestinal complications was found between slow and rapid feeding groups.

Lower intestinal oxygenation was associated with feeding intolerance in preterm infants.

Abstract

What are the main findings?
Intermittent bolus feeding increased intestinal oxygenation, with a more pronounced percentage change observed during and after feeding in the rapid advancement group.No significant difference in gastrointestinal adverse outcomes, such as feeding intolerance or necrotizing enterocolitis, was found between the slow and rapid advancement groups.The use of abdominal near-infrared spectroscopy allowed continuous, real-time assessment of mesenteric oxygenation, demonstrating its potential value as a non-invasive monitoring tool in preterm infants.

Intermittent bolus feeding increased intestinal oxygenation, with a more pronounced percentage change observed during and after feeding in the rapid advancement group.

No significant difference in gastrointestinal adverse outcomes, such as feeding intolerance or necrotizing enterocolitis, was found between the slow and rapid advancement groups.

The use of abdominal near-infrared spectroscopy allowed continuous, real-time assessment of mesenteric oxygenation, demonstrating its potential value as a non-invasive monitoring tool in preterm infants.

What is the implication of the main finding?
Rapid advancement of enteral feeding, when closely monitored clinically and/or with abdominal near-infrared spectroscopy, may be safely implemented without increasing the risk of gastrointestinal complications.

Rapid advancement of enteral feeding, when closely monitored clinically and/or with abdominal near-infrared spectroscopy, may be safely implemented without increasing the risk of gastrointestinal complications.

Background/Objectives: The optimal rate of enteral feeding advancement in preterm infants remains uncertain despite decades of clinical research. This uncertainty arises from concerns that rapid feeding progression may increase the risk of feeding intolerance and necrotizing enterocolitis (NEC), two major causes of morbidity and mortality in this population. The feeding rate may also influence intestinal oxygenation due to mesenteric hemodynamic changes during feeding. This study aimed to evaluate whether the rate of enteral feeding advancement (slow vs. rapid) affects intestinal oxygenation and its association with feeding intolerance (FI) or necrotizing enterocolitis in very low birth weight preterm infants. Methods: This prospective, randomized, two-center study included infants born at 28–32 weeks of gestation. Group 1 received slow advancement (20 mL/kg/day) and Group 2 rapid advancement (30 mL/kg/day) of enteral feeds. Splanchnic (srSO2) and cerebral (crSO2) oxygenation were monitored daily using the FDA-approved INVOS NIRS device during feeding periods (08:00–16:00). Monitoring was performed during minimal enteral nutrition (Phase 1), advancement phases (Phase 2), and for two days after achieving full enteral feeding (Phase 3). The splanchnic-to-cerebral oxygenation ratio (SCOR) was also calculated. Percentage changes in srSO2 and SCOR during and after feeding were calculated from baseline (prefeeding) values and analyzed. Results: Sixty infants were enrolled. Mean gestational age and birth weight were 29.76 ± 1.33 weeks and 1375.05 ± 271.19 g, respectively. Group 2 achieved full enteral feeding significantly earlier (p = 0.001), with no other demographic differences between groups. No cases of NEC were observed. Feeding intolerance occurred in 14 infants (23.3%): 8 in Group 1 and 6 in Group 2 (p = 0.192). Both groups exhibited increased srSO2 and SCOR during feeding; however, the between-group differences were not statistically significant (Phase 2 srSO2 and SCOR: p = 0.07, 0.08; Phase 3 srSO2 and SCOR: p = 0.069, 0.071). However, the percentage change from baseline in srSO2 and SCOR during and after feeding was significantly greater in Group 2 during the advancement and full enteral feeding phases (Phase 2 srSO2 and SCOR: p = 0.03, 0.022; Phase 3 srSO2 and SCOR: p = 0.015, 0.048). Infants with feeding intolerance demonstrated significantly lower srSO2 and SCOR values compared to tolerant infants, and this reduction persisted even after reaching full enteral feeding. ROC analysis suggested gestational age < 30 weeks, birth weight < 1180 g, srSO2 < 52, and SCOR < 0.6 were associated with feeding intolerance. Conclusions: Intermittent bolus feeding increased intestinal oxygenation, with a more pronounced effect in the rapid advancement group. No difference in gastrointestinal adverse outcomes was observed between groups. Lower intestinal oxygenation was associated with feeding intolerance, and the suggested predictive criteria may help guide individualized feeding strategies.

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