Boehm G, Müller M D, Senger H, Melichar V
Department of Paediatrics, Karl-Marx-University, Leipzig, GDR.
Acta Paediatr Hung. 1990;30(3-4):423-33.
In 14 very low birth weight (VLBW) infants appropriate for gestational age the absorption and retention of nitrogen and the energy balance were studied on the 8th day and the 6th week of postnatal age. All infants were fed with a human milk formula composed by fresh mother's milk enriched with 6 g freeze-dried human milk/100 ml. The absorption rates of nitrogen and fat increase significantly with postnatal age but even on the 8th day of life they are on high levels (nitrogen absorption: 86.9 +/- 3.2% of intake; fat absorption: 85.7 +/- 4.3% of intake). Despite the higher nitrogen absorption during the 6th week of life the excretion of total nitrogen is lower in comparison to the 8th day of life. Similarly, the percentages of alpha-amino-nitrogen and of ammonium-nitrogen of the total nitrogen excretion in the urine decrease whereas the percentage of urea-nitrogen increases with postnatal age. The results indicate a postnatal development of both the digestive, as well as the metabolic capacity. The postnatal adaptation of the metabolic capacity to utilize nitrogen seems to be the stronger limiting factor for nutrition than the functional capacity of digestion and absorption. Thus, metabolic monitoring is essential for the individual nutrition of VLBW-infants during the first weeks of postnatal life. Urine analysis data are very sensitive for evaluating the metabolic state of these infants.
对14例适于胎龄的极低出生体重（VLBW）婴儿在出生后第8天和第6周时的氮吸收与潴留及能量平衡进行了研究。所有婴儿均喂食一种由新鲜母乳强化6 g冻干人乳/100 ml组成的人乳配方奶。氮和脂肪的吸收率随出生后年龄显著增加，但即使在出生后第8天，它们也处于较高水平（氮吸收：摄入量的86.9 +/- 3.2%；脂肪吸收：摄入量的85.7 +/- 4.3%）。尽管在出生后第6周时氮吸收较高，但与出生后第8天相比，总氮排泄量较低。同样，尿液中总氮排泄中α-氨基氮和铵氮的百分比降低，而尿素氮的百分比随出生后年龄增加。结果表明消化和代谢能力在出生后均有发育。代谢能力对氮利用的出生后适应性似乎是比消化和吸收功能能力更强的营养限制因素。因此，在出生后最初几周对VLBW婴儿进行个体营养时，代谢监测至关重要。尿液分析数据对评估这些婴儿的代谢状态非常敏感。
