Nutritional management of newborn infants: Practical guidelines

Table 1 Evidence-based enteral nutrition in preterm newborns

	Evidence-based enteral nutrition
Human milk	Human milk from the preterm infant's own mother is the first choice. Human milk can be stored at room temperature for up to 24 h after expression in colostrum and up to 6 h for mature milk. Beyond that, it should be stored at 3-4°C before use. If not used for more than 5 d, it should be frozen
Human milk fortifier	Human milk fortifier is indicated in preterm infants < 31 wk and/or < 1500 g. Human milk (100 mL/kg) is given per day and discontinued when the infant has established full breast-feeding
Formula milk	If human milk from the preterm infant's own mother is not available, the only acceptable alternative is a preterm formula. A concentration of about 60 kcal/100 mL or 20 kcal/oz is recommended, but should be increased to 80 kcal/100 mL or 24 kcal/oz when the infant has achieved full enteral feeds
Feeding methods	Gavage feeding is given via an indwelling nasogastric tube during mechanical ventilation. An indwelling orogastric tube is used after endotracheal extubation. Intermittent intragastric feeding is the first choice method, but continuous transpyloric feeding can be tried in selected preterm infants with extremely poor gastric emptying and symptomatic gastro-esophageal reflux
Commencement of feeds	Hourly feeds of 1 mL are generally used in infants weighing less than 1000 g, 2-h 2 mL for infants weighing 1000-1500 g, 3-h 3 mL for infants weighing 1500-2000 g, and 4-h 4 mL for infants weighing more than 2000 g, unless there is significant respiratory distress, when the infant remains on 1-2-h feeds. If this might not be tolerated, milk may be commenced at 1 mL every 2 h, even less than 1 mL every 4-6 h. Such trophic feeding should begin as soon as possible after birth, and definitely within the first 3-4 d
Progression of feeds	Daily increment in the range of 10-30 mL/kg of milk feeds is safe. Demand feeding is started after infants have established full milk feeds on a 4 h regimen. Non-nutritive sucking is beneficial without side effects
Supplements	Multivitamin supplement is started when the infant has established full enteral feeds, and iron is started when the infant has doubled their birth weight (usually at 2 mo). Medium-chain triglycerides can be used as an energy supplement for preterm infants who fail to thrive

Table 2 Evidence-based PN in preterm newborns

	Evidence-based PN
Fluids	D 1: 60-80 mL/kg per day. Infants < 28 wk gestation are nursed in a maximally humidified environment (90% humidity) for at least 7 d. Postnatal weight loss of 5% per day to a maximum of 15% is acceptable, which is achieved by progressively increasing the fluid intake to 120-150 mL/kg per day at 1 wk of age
Energy	An intake of 50 kcal/kg per day is sufficient to match ongoing expenditure, but it does not meet additional requirements of growth. The goal energy intake is 120 kcal/kg per day, which is higher in infants with chronic lung diseases
Protein	Optimal parenteral amino acid intake is 3.5 g/kg per day. Parenteral amino acids can begin from day 1 at a dose of 1.75 g/kg per day
Carbohydrate	From day 1, 6-10 g/kg per day can be infused and adjusted to maintain blood glucose level of 2.6-10 mmol/L. Insulin is only used in infants whose blood glucose level is higher than 15 mmol/L and associated with glycosuria and osmotic diuresis, even after glucose intake has been decreased to 6 g/kg per day. Carbohydrate is given as a continuous infusion commencing at a rate of 0.05 U/kg per hour, and increased as required for persistent hyperglycemia
Fat	Intravenous fat, 1 g/kg per day, can be started from day 1, or when intravenous amino acids are started. The dose of intravenous fat is increased to 2 g/kg and 3 g/kg per day over the next 2 d. Twenty percent intravenous fat is delivered as a continuous infusion via a syringe pump, separated from the infusate containing amino acids and glucose. The syringe and infusion line should be shielded from ambient light
Minerals	Minerals should include sodium (3-5 mmol/kg per day), chloride (3-5 mmol/kg per day), potassium (1-2 mmol/kg per day), calcium (1.5-2.2 mmol/kg per day), phosphorus (1.5-2.2 mmol/kg per day), and magnesium (0.3-0.4 mmol/kg per day)
Trace elements	Trace elements should include zinc (6-8 μmol/kg per day), copper (0.3-0.6 μmol/kg per day), selenium (13-25 nmol/kg per day), manganese (18-180 nmol/kg per day), iodine (8 nmol/kg per day), chromium (4-8 nmol/kg per day), and molybdenum (2-10 nmol/kg per day)
Vitamins	Vitamins must be added to the fat emulsion to minimize loss of vitamins due to adherence to tubes and photodegradation