Sabita Uthaya, Xinxue Liu, Daphne Babalis, Caroline Dore, Jane Warwick, Jimmy Bell, Louise Thomas, Deborah Ashby, Giuliana Durighel, Ash Ederies, Monica Yanez-Lopez, and Neena Modi
Background: Parenteral nutrition (PN) is central to the care of very immature infants. Early intakes of higher amounts of amino acids and the use of lipid emulsions containing fish oils are recommended by current international recommendations. Objective: To confirm the safety and demonstrate efficacy of the immediate introduction of the recommended daily intake of amino acids (Imm-RDI) and soya bean oil, medium-chain triglycerides, olive oil and fish oil lipid in PN to increase non-adipose (lean) body mass and decrease intrahepatocellular lipid (IHCL) content. Design: Multicentre, double-blind, 2 × 2 factorial and randomised controlled trial (RCT). Setting: Neonatal units in London and south-east England, UK. Participants: Extremely preterm infants born before 31 weeks of gestation without major congenital or life-threatening abnormalities who could to be randomised to receive PN within 24 hours of birth. Interventions: Infants were randomised within 24 hours of birth to receive PN containing either high [RDI of amino acids (Imm-RDI)] or low [incremental amino acids (Inc-AA) control] levels of amino acids. In addition, infants were randomised to receive either 20% SMOFlipid® (Fresenius Kabi AG, Richmond Hill, ON, Canada) or 20% Intralipid® (Fresenius Kabi AG, Richmond Hill, ON, Canada) (control). This resulted in four groups: (1) Inc-AA/Intralipid, (2) Inc-AA/SMOFlipid, (3) Imm-RDI/Intralipid and (4) Imm-RDI/SMOFlipid. The intervention was continued until infants were receiving 150 ml/kg/day of enteral feeds for 24 hours. Primary outcome measure: For the amino acid intervention, this was non-adipose or lean body mass measured by magnetic resonance imaging. For the lipid composition intervention, this was IHCL content as measured by hepatic magnetic resonance spectroscopy. Primary outcomes were measured at term age equivalent, between 37 and 44 weeks postmenstrual age. Results: We randomised 168 infants born before 31 weeks of gestation. We evaluated outcomes, at term, in 133 infants. There were no significant differences in non-adipose mass between the Imm-RDI and Inc-AA groups [adjusted mean difference 1.0 g, 95% confidence interval (CI) –108 to 111 g] or in levels of IHCLs between the SMOFlipid and Intralipid groups (adjusted mean SMOFlipid to Intralipid ratio 1.1, 95% CI 0.8 to 1.6). Infants receiving the Imm-RDI were more likely than Inc-AA infants to have blood urea nitrogen levels > 7 mmol/l [75% vs. 49% (p 10 mmol/l [49% vs. 18% (p