Vagal Tone and Proinflammatory Cytokines Predict Feeding Intolerance and Necrotizing Enterocolitis Risk.

Only neonates born at 26-34 weeks' post-menstrual age who were physiologically stable by 72 hours of life were included, and extremely low birthweight or critically unstable neonates were excluded. The sample was mostly White, non-Hispanic, so the findings may not apply broadly across populations. Neonates with late-onset infection in the absence of NEC or feeding intolerance were excluded from the outcome analyses. Some analyses were post-hoc, and subgroup analysis by post-menstrual age at birth had groups too small for statistical testing. Small for gestational age was associated with NEC stage 2 or higher in a post-hoc analysis, but it could not be tested in predictive models because it overlapped with illness severity. The NEC stage 2 or higher incidence was 4.1%, lower than the 12% reported in the authors' previous study, and concurrent quality improvement changes may affect generalisability. The study was observational; it does not show that heart rate variability, cytokines, handling practices, or family-integrated care prevent NEC or feeding intolerance.

Do not conclude that heart rate variability or cytokine tests can identify NEC risk in your unit, or that the discussed nursing strategies prevent NEC. This was an observational study of selected stable preterm neonates, and the predictors were not tested as interventions.