Does more protein in the first week of life change outcomes for very low birthweight babies?

Background: Following publication of revised recommended nutrient intakes (RNI) for infants <1500 g, our intravenous nutrition (IVN) solutions were reformulated to deliver RNI in a restricted volume to ensure additional non-nutritional fluids did not detract from nutritional intake. An audit was performed to determine whether these changes achieved RNI and influenced growth, clinical or neurodevelopmental outcomes. Methods: Two cohorts of 40 infants < 1500 g were identified from a prospectively maintained database: babies born before and after reformulation of the IVN solutions. Data on nutritional intakes for the first 30 days of life, growth and clinical outcomes were collected. Neurodevelopmental outcomes at 18 months corrected age (CA) were obtained from a Bayley III assessment. Results are presented as mean +/- SD. Results: The 'after' group received significantly less fluid (105 +/- 12 vs. 132 +/- 15 mL/kg/day, P < 0.001) but more protein (3.2 +/- 0.6 vs. 2.4 +/- 0.5 g/kg/day, P < 0.001) in the first week of life. There were no differences in clinical outcome, growth z-scores at 4 weeks of age or neurodevelopmental outcome at 18 months CA between the 'before' and 'after' infants. Enteral protein intake in the first 2 weeks of life was positively associated with neurodevelopmental outcome (cognitive score r(2) = 0.13 P = 0.03, motor score r(2) = 0.27 P = 0.001). Conclusion: Although the new IVN regimen achieved intakes closer to RNI, there were no major effects on growth, clinical outcome or neurodevelopmental outcome at 18 months CA. Enteral protein intake in the first two weeks was positively associated with neurodevelopmental outcome, suggesting early enteral protein intake is important for optimal brain function.