Maximizing Protein Growth in the Early Neonatal Period

描述（由申请人提供）：在这个国家，目前对早产儿的营养策略导致新生儿在出院时无法恢复的产后生长衰竭。营养不良，特别是关键发育时期蛋白质摄入不足，会对长期神经发育和健康结果产生不利影响。因此，优化营养支持的努力，特别是在生命的最初几周，对于扭转这一弱势群体的营养相关不良后果至关重要。美国儿科学会（American Academy of Pediatrics， AAP）建议模仿与早产儿相同胎龄的正常胎儿的生长速度，这是唯一一项全国性的建议，为早产新生儿提供全面的营养，直到出院。美国儿科学会没有关于如何实现这一目标的指导方针，也没有文献数据支持或反驳这一建议。我们认为确定这是否是一个有效的建议是至关重要的。本项目要解决的首要假设是，在营养敏感的产后早期，极低出生体重（ELBW）早产儿的蛋白质增积率可以显著提高。我们相信，提出的蛋白质数量、蛋白质质量和能量摄入对蛋白质增加的前瞻性研究将增强优化这些婴儿蛋白质增加的能力。需要解决的具体假设有：1)与目前的氨基酸起始和推进策略相比，在新生儿期开始相对较高的氨基酸和能量摄入，并通过密切监测生命前2个月的营养摄入来维持胎儿的分娩率，将赋予长期的合成代谢优势。并将决定给予早产儿的胎儿营养输送率是否能达到美国儿科学会的建议，即宫外生长应接近相同胎龄的胎儿；2)可以确定肠外营养中必需氨基酸的最佳浓度，以提高氨基酸摄入质量，从而最大限度地提高蛋白质的增加率；3)可以确定能量摄入量，在任何给定的氨基酸摄入量下，将优化蛋白质的增加。

DESCRIPTION (provided by applicant): Current nutritional strategies for very preterm infants in this country are resulting in postnatal growth failure from which the neonate does not recover by the time of hospital discharge. Undernutrition, particularly insufficient protein intake during critical development periods adversely affects long-term neurodevelopmental and health outcomes. Efforts to optimize nutritional support, therefore, particularly in the first weeks of life, are critical to reversing nutritionally related adverse outcomes in this vulnerable population. The only national published recommendation for providing comprehensive nutrition to the preterm neonate through the time of discharge is the American Academy of Pediatrics (AAP) recommendation to mimic the growth rate of the normal fetus of the same gestational age as the preterm jnfant. There are no guidelines by the AAP as to how this should be achieved, and no data in the literature to support or refute this recommendation. We believe that it is critical to determine if this is a valid recommendation. The overarching hypothesis to be addressed by this project is that protein accretion rates can be significantly improved in extremely low birth weight (ELBW) preterm infants during the critical nutritionally-sensitive early postnatal period. We believe that the proposed prospective studies of protein quantity, protein quality and energy intake on protein accretion will enhance the ability to optimize protein gain in these infants. Specific hypotheses to be addressed are: 1) that relatively high amino acid and energy intake initiated in the immediate neonatal period and sustained at fetal delivery rates through close monitoring of nutrient intake over the first 2 months of life will confer a prolonged anabolic advantage compared to current amino acid initiation and advancement strategies, and will determine whether or not fetal nutrient delivery rates administered to the preterm infant will achieve the AAP recommendation that extrauterine growth should approximate that of the fetus at the same gestational age; 2) that optimal concentrations of essential amino acids in parenteral nutrition can be determined that will improve the quality of amino acid intake in order to maximize protein accretion rates; and 3) that energy intakes can be identified that will optimize protein accretion at any given amino acid intake.