GLUCOSE METABOLISM IN NEWBORN INFANTS WITH CONGENITAL HEART DISEASE

这个子项目是许多利用 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 摘要 患病新生儿，包括先天性心脏病新生儿，通常在出生后的头几天需要全肠外营养（TPN），直到他们能够耐受肠内喂养。 这些婴儿，以及那些早产儿，有葡萄糖代谢紊乱和能量补充不足的风险。 为了防止低血糖并提供足够的能量摄入，这些新生儿中的一些通常以约两倍于其正常葡萄糖转化率的速率（：6 mg/kg/min）接受葡萄糖。 该方案导致高血糖症频繁发生，特别是在早产儿和患病婴儿中。 我们不知道改变葡萄糖输注速率如何影响先天性心脏病新生儿的葡萄糖代谢和血糖水平。 本研究旨在探讨不同葡萄糖输注速率对先天性心脏病新生儿糖、脂、蛋白质代谢的影响。 了解这些患病新生儿的葡萄糖代谢生理学，使我们能够制定适当的肠外营养，使这些婴儿血糖正常，并为他们提供足够的能量摄入，这对我们来说很重要。 假设 与提供6 mg/kg/min葡萄糖（正常葡萄糖周转率）的TPN相比，常规TPN（通常以相当于正常葡萄糖周转率约两倍的速率提供葡萄糖）更可能发生高血糖。 患有先天性心脏病的新生儿能够在6 mg/kg/min葡萄糖输注速率期间维持正常血糖（同时维持胃肠外脂质和氨基酸的输注速率不变）。 在接受常规TPN以两倍于正常周转率提供葡萄糖的情况下，患有心脏病的婴儿的葡萄糖生成，特别是新生儿的葡萄糖生成，并没有被完全抑制。 接受6 mg/kg/min TPN的患病婴儿全身蛋白质合成减少。 具体目标 本研究的目的是使用已建立的稳定同位素-GCMS技术，确定常规TPN（提供约两倍于正常转换率的葡萄糖燕麦）和降低葡萄糖输注速率以对应于正常葡萄糖转换率（同时保持肠内脂质和氨基酸输注速率不变）对先天性心脏病婴儿葡萄糖、脂质和蛋白质代谢的影响。 这将使我们能够确定葡萄糖输注速率对患有先天性心脏病的新生儿的代谢影响。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. ABSTRACT Sick neonates, including those with congenital heart disease, usually require Total Parenteral Nutrition (TPN) during their first several days of life until their ability to tolerate enteral feeds is well established. These infnats, as well as those born prematurely, are at risk of disturbed glucose metabolism and inadequate energy supplejentation. In an effort to prevent hypoglycemia and to provide a sufficient energy intake, some of these neonates are routinely receiving glucose at rates about twice their normal glucose turn over rate (: 6 mg/kg/min.) This regimen results in a frequently occurrence of hyperglycemia, particularly in premature and sick infants. We do not know how changing the glucose infusion rate affects the glucose metabolism and the blood glucose levels innewborns with congenitalheart disease. The purpos of this project is to determine the effects of different glucose infusion rates on glucose, lipid, and protein metabolism innewborn infants with congenital heart disease. It is important for us to learn about the physiology of glucose metabolism in these sick neonates to enable us to formulate an adequate parenteral nutrition that renders these infants normoglycemic and provide them with a sufficient energy intake. HYPOTHESIS Hyperglycemia is more likely to occur during routine TPN (usually providing glucose at rates corresponding about twice the normal glucose turnover rate) than during a TPN providing glucose at 6 mg/kg/min (normal glucose turnover rate). Newborn infants with congenital heart disease are able to maintain normoglycemia during a 6mg/kg/min glucose infusion rate (while maintaining the infusion rates of parenteral lipids and amino acids unchanged). Glucose production, particularly gluconeogenesis, is not completely suppressed in infants with contential heart disease while receiving a routine TPN providing glucose at twice normal turnover rate. Whole-body protein synthesis is reduced in sick infants receiving TPN providing at 6mg/kg/min. SPECIFIC AIMS The purpose of this study is to determine the effects of routine TPN (providing glucose oat about twice normal turnover rates), and of reducing the infusion rate of glucose to correspond to the normal glucose turnover (while maintaining the infusion rates of paenteral lipids and amino acids unchanged) on glucose, lipid and protein metabolism in infants with congenital heart disease using established Stable Isotope-GCMS techniques. This will allow us to determine the metabolic effects of glucose infusion rate in sick newborn infants with congenital heart disease.