Abstract

Nutrition of neonates in intensive care (NICU)is aimed for the supply of energy ,protein and other elements required for growth and normal development. Intrauterine provision of nutrients in uncomplicated pregnancy, followed by breast feeding by own mother is recognized as the ideal, unattainable pattern of a properneonatal nutrition. The population of patients in NICU is mainly consisted of very low or extremely low birth weight premature infants or infants in metabolic stress: with multiorgan failure, SIRS, with birth trauma or after surgery. These newborns have very small energy reserves, but very often the natural enteral way of feeding is excluded or seriously limited. In the same time co-existing negative factors changed the metabolic processes for catabolism. Intensive care of such patients includes the optimal provision of nutrients in respect to way of supply ontents and amount, in order to reverse metabolism on anabolic pathway without causing injury. The strategy of care should be based on studies ’results on fetal and neonatal metabolism. Very high level of metabolic processes in fetal life is already acknowledged. The glucose supply is adequate to the energy needs, enables the fetus to keep blood glucose concentration on stable level around 50 mg/dl, with relatively low insulin concentration. Glucose consumption is reduced with the course of pregnancy. The third trimester of intrauterine life is the time for more pronounced role of lipids in energy production and at birth the body is consisted in 15%of fat (the highest value among all land mammals).The quantity and the quality of lipid sub- stances are crucial for cellular membranes development, especially in central nervous system and vessels and also signaling transmitters. Aminoacids intake, actively transported via placenta is high and exceeds amounts needed for fetal growth (the surpluses become the source of energy).Nutritional needs –especially of premature newborns -are not changed with the moment of birth and only few hours of starvation can be allowed. A sudden cut in energy supply leads to increase in protein degradation and drastic change for catabolic processes. The immediate, in a couple of hours after the labor, supplementation of essential nutrients,b followed in nextdays by any necessary -according to the clinical status modification, is fundamental in neonatal nutrition The alimentary strategies are based on the certitude that neonatal metabolic requirements are equal or higher than fetal. Sufficient amount of fluids, estimated on exact input –output evaluation and frequent body weighing, plays the key role in intensive care management. The next point is the initial glucose supply of 5 –7 mg per kilogram per minute, increased in reasonably short time with the respect to serum glycemia. Insulin drip administration should be very carefully considered, after failure of the other methods of reduction in glucose concentration (the increase in aminoacids provision, the decrease in glucose daily load)and after exclusion of acute phase of sepsis. Early (even on the first day of life)and high (up to 3 grams per kilogram per day) aminoacids supplementation controls not only a growth rate but also may positively influence endogenous insulin secretion. According to same novel results from the leading research centers, lipids can be initiated on the first day of life and achieve 3 grams per kilogram per day in the next 72 hours. Calcium, phosphorus, magnesium, similarly as vitamins and trace elements, should not be omitted in well-balanced nutrition, however their influence on metabolism in ill, unstable infants is not fully known. Enteral feeding is recommended parallel to parenteral nutrition, in amounts adjusted to the clinical status and by the mode most appropriate to patient ’s condition. Minimal trophic feeding with breast milk is usually well tolerated even in ELBW and ILBW. Not only basic components of breast milk are optimal for newborns, but also unique hormonal and immunological substances should not be neglected. Infant formulas –still being improved –are modeled on breast milk, also in immunonutrients.These last ones are not fully explored, but never the less seemed to be of high importance. The effects of early nutritional proceeding are stretched over time, which should be kept in mind while performing alimentary support to premature or ill newborns. Proper supply of nutrients allows overcoming current health instability and influences significantly survival of infants in meta- bolic stress. On the other hand, its longitudinal effects are imprinted on the quality of life in the following months and years.

Keywords: newborn, Intensive Care, total parenteral nutrition, Enteral Nutrition, Metabolism