Comparison of Early vs Late Parenteral Nutrition in Term and Late Preterm Infants

There is limited evidence on the optimal timing for initiating parenteral nutrition (PN) in term and late preterm infants. A single-centre, non-blinded, exploratory randomized controlled trial evaluated this question in infants born at ≥34 weeks of gestation, within 28 days of age, who required PN. Eligible infants were randomized to receive PN either early (day 1–2 of admission) or late (day 6 of admission).

The primary outcomes were plasma phenylalanine and F2-isoprostane levels on days 4 and 8. Secondary outcomes included amino acid and fatty acid profiles, as well as clinical measures.

Key findings:

• Postnatal age at randomization was similar across groups (2.3 days).
• By day 4, phenylalanine levels were significantly higher in the early-PN group compared to late-PN (62.9 vs 45.5 µmol/L), though differences resolved by day 8
• F2-isoprostane levels did not differ significantly between groups at either timepoint.
• Early-PN infants experienced less severe weight growth restriction (change in weight z-score: -0.6 vs -1.0).
• Early PN was associated with a higher incidence of hyperglycemia (66.7% vs 36.7%).

Conclusion: The timing of PN initiation did not influence oxidative stress in critically ill term and late preterm infants. While early PN reduced growth restriction, it was linked to higher plasma phenylalanine levels and greater risk of hyperglycemia. Further studies are warranted to clarify the long-term clinical implications of these findings.

Source: Moon K, McKinnon E, Croft K, Hendrie D, Patole S, Simmer K, Rao S. Early versus late parenteral nutrition in term and late preterm infants: study protocol for a randomised controlled trial. BMC Pediatr. 2022;22(1):514.