Individualized Nutrition

Nutrition is fundamental for optimal growth and long-term health of preterm babies. Preterm infants have higher nutrient requirements than term infants. One reason for this is that they miss the third trimester of pregnancy which is the intended period of nutrient accumulation and rapid growth. Precise nutrition is crucial for optimal growth of the body, organs and for lifelong quality of life, as early nutritional deficit can cause impaired neurological development. Modern neonatal care has improved the survival rate of extremely preterm infants. These infants are at high risk of malnutrition and growth failure during the first months of hospital care.

Nutrition is fundamental for optimal growth and long-term health of preterm infants. Very preterm (VPT, < 32 wk) or very low birth weight (VLBW, < 1500 g) infants are at high risk of malnutrition. Unlike term newborns, these infants are born with only minimal nutrient stores. Thus, when the placental nutrient supply is interrupted, these infants need enteral and parenteral nutrition already from the first day of life. Furthermore, they have very high nutrient requirements – the smallest preterm infants are expected to increase fourfold or even fivefold in weight during 3-4 months stay in the neonatal care unit (NICU).

Multiple studies have shown that VPT/VLBW infants often develop severe nutrient deficits (energy, protein and other nutrients) during care in the neonatal intensive care unit, even when they have received both enteral and parenteral nutrition. There are multiple causes for this, including practical difficulties in administering enteral and parenteral nutrition in infants with significant co-morbidities. But an important reason is also that it is difficult for the NICU staff to keep track of the nutrient intakes of these infants, who often receive a combination of enteral and parenteral nutrition together with multiple nutrient supplements.

Poor nutrient intakes in preterm infants have been associated with poor growth, increased risk of retinopathy of prematurity, bronchopulmonary dysplasia and later poor neurodevelopment. Furthermore, individual deficits or overload of specific nutrients may cause severe and even life-threatening metabolic imbalances, including hypo- or hyperglycemia, hyper- or hyponatremia, hyper- or hypocalcemia and hypophosphatemia.

The care of preterm infants has improved rapidly during the last 20-30 years. As a result of improved intensive care, the survival rates of extremely preterm infants has increased considerably, even at very low gestational ages and birth weights well below 1000 g. However, these infants are still at high risk of short-term and long-term morbidities, including retinopathy of prematurity, bronchopulmonary dysplasia and later cognitive and behavioural problems. The remaining challenge in preterm care is now how to improve the health outcomes for these ”new survivors”. Early nutrition has been identified as a key target for quality improvement, since it has been shown to reduce the risk of poor health outcomes.

Due to a pro-active approach, Sweden has excellent survival rates of preterms even at 22 and 23 weeks of gestation. In the national EXPRESS study, based on extremely preterm infants born between 2004-2007, it was shown that nutrient intakes during the first weeks of life were much lower than recommended and that these infants showed severe postnatal growth failure. This has subsequently led to significant improvements in preterm nutrition in Swedish neonatal intensive care units. The Nutrium system was developed and is now used at the vast majority of Swedish neonatal units for daily nutrition prescriptions as well as for nutrition and growth monitoring.

Sweden has a well-developed system of milk banks, facilitating the use of donor milk when the mother’s own milk is not available. Since the fat and protein content of breast milk is highly variable among individuals and over time, Sweden has a long tradition of analysing breast milk for macronutrient content and using this information to guide breast milk fortification. The feedback from the Nutrium system has led to improved practice with regard to enteral nutrition, including earlier fortification of breast milk, as well as parenteral nutrition, including more concentrated parenteral nutrition solutions. The system has also resulted in greatly improved interest and knowledge about preterm nutrition among neonatologists, neonatal nurses and dieticians. Studies have shown that these improvements have resulted in improved nutrient intakes and improved growth of preterm infants in Sweden.