Enteral nutrition in preterm neonates

Infants with birth body weight less than 1500 g develop a postnatal growth failure in the vast majority of the cases. To limit this risk, enteral nutrition should be introduced appropriately, with the respect to actual requirements of preterm neonates. Administration of enteral nutrition depends on postnatal age and clinical conditions. During the early adaptive period of life (from birth to approximately day 7), hemodynamic instability associated with immaturity of the gastrointestinal tract limit the use of enteral nutrition. Parenteral nutrition represents the main route of administration of nutrients in this period. However, enteral nutrition should be started since the first 1-2 days of life as minimal enteral feeding (10-30 ml/kg/d) and progressively increased (by 20-30 ml/kg/d) until full enteral feeding is reached (120 kcal/kg/d) and, contemporarily, parenteral nutrition could be stopped. In the stable growing period (from approximately day 7 to near term/discharge) all nutritional requirements, including macronutrients and micronutrients, should be reached only by enteral nutrition. Human milk is the preferred form of enteral nutrition for preterm babies, however fortification with adequate amount of protein, carbohydrates, lipids, electrolytes and micronutrients should be adopted to respect nutritional needs of these subjects. In this Chapter we focused on modalities to reach nutritional requirements by enteral nutrition.