What are the interventional strategies to promote appropriate growth?
During an interview, Prof. Ekhard Ziegler discusses the latest research on interventional strategies to promote growth in low-birth weight infants.
Dear Eckhart, when a baby is born with low birth weight, can inter-uterine growth rates be achieved when there is a critical period of the birth or will the baby fall behind? And what are neonatologists doing?
The short answer is all babies lose weight, they lose weight immediately after birth and they continue to lose weight as they grow. We call it post-natal growth failure or extra-uterine growth failure and they fall off where they would have grown in the fetus.
Now we know that this growth failure is, in a dose-dependent fashion associated with poor neurocognitive outcome. The more severe the growth failure the worse the neurocognitive outcome at two years or even later on in life. We know that all neonatologists strive to prevent, or to ameliorate this growth failure but nobody has succeeded in making premature babies grow exactly like the fetus nobody has.
A premature baby needs more calories and more proteins than a term baby. It is very important not only the quantity of protein and calories which you can give, but also the quality.
What is the role of mother's milk?
Premature babies have much higher nutrient needs than full terms babies, they need more protein and minerals.
Mother's milk is designed for full terms babies and does not contain enough protein, calcium and phosphorus for the premature babies and that is the reason why we add these nutrients, we call it nutrient fortification.
The issue of providing nourishment to the premature baby is much more complicated than that. It is complicated by the fact that the gastrointestinal tract of the premature infant is very immature at the beginning and we cannot rely on feeding the baby for days and weeks.
All we can do is put small amounts of food into the stomach of the baby and wait until the gastrointestinal tract becomes mature so that it moves things forward and absorbs things. During that time we have to provide nutrition parentally - that means into the veins, and that is something that is now widely practiced by all neonatologists.
Not all do it in a satisfactory way but pretty much all neonatologists provide parenteral nutrition and then go about stimulating the immature gastrointestinal tract to the point where it can accept full nutrients.
The baby start to grow, and the low birth weight infant reaches 4-5kgs body weight, does it still have specific needs or the needs will be according to the term infant?
When the baby goes home, he/she typically weighs 2.5kgs at that point.
The baby's needs are still higher than those of a full term baby and that is why we have special formulas for babies or when they go home breastfeeding we still fortify the milk. But once they reach 5kgs we are sure that the baby's needs are comparable to those of a full term baby.