Background Term born infants demonstrate an increase in intestinal perfusion after receiving enteral feeding (postprandial intestinal hyperemia). It remains unclear whether enteral feeding influences intestinal perfusion in preterm infants.

Aim To assess the effect of enteral feeding on intestinal perfusion in preterm infants.

Methods This study was part of a larger prospective cohort study. We used near-infrared spectroscopy to measure regional intestinal oxygen saturation (r_intSO₂), which is indicative for intestinal perfusion. We measured during two hours on postnatal days 2–5, 8, 15, 22, 29, and 36. Feeding times were manually recorded. We used Multi-level analyses to compare preprandial (baseline) r_intSO₂ values to postprandial r_intSO₂ values, both 10–30 min and 30–60 min after feeding.

Results We included 29 preterm infants with a median GA of 28+1/7 (range 25+1/7–30+4/7) weeks, and a median birth weight of 1025 (range 580–1495) grams. Compared to preprandial values, we only found decreased postprandial r_intSO₂ values 30–60 min after feeding (mean[SD]: from 47%[22] to 41%[19], p = 0.007) on day 5. We observed increased r_intSO₂ values 10–30 min after feeding compared to preprandial values on day 29 (mean[SD]: from 51%[14] to 42%[14], p = 0.005).

Conclusion Our results suggest that in preterm infants during their first three weeks of life, intestinal oxygen saturation does not increase, and sometimes even decreases, the first hour after feeding. One might speculate that preterm infants are not yet able to increase intestinal perfusion rates after feeding, an increase which might be necessary to meet metabolic demands.