Premature babies are by nature
immature and their gut is easily “upset”. Unlike an adult with an upset tummy or
gastroenteritis the premature infant’s
bowel is subject to a condition called necrotizing enterocolitis (also known as
NEC).
This
inflammation of the
gut (
small and/or large intestine) can vary in degree, both in terms of the thickness of the bowel segment involved and in terms of the length of the bowel segment involved. Of course NEC of only a short segment of the innermost lining is less severe than a case of full thickness NEC involving a large portion of the bowel. In the first case the infant may recover with just
medical support (antibiotics and resting of the bowel). In the second case
surgical removal of the
necrotic tissue is required and the infant may be left with a
short gut causing nutritional absorption problems, scaring may cause
bowel obstruction, the baby may need an
ileostomy, and/or it may
die, before, during or after the
surgery.
NEC is so serious that it is treated just on
suspicion. Very small premies are constantly assessed for general well being as well as to the efficiency of their
digestion (do they have residual food in their tummy when it “should” have already been digested) and is their tummy soft, of a normal color and not distended. Their
enteral feeding begins slowly to allow for tolerance while they are nutritionally sustained with
total parenteral nutrition. At any sign of NEC, enteral nutrition is “held” (not given) and then only slowly reintroduced.
The feeding of a premature infant is difficult because the premature gut, just like the premature lung is not meant to be put into use just yet. Breastmilk is the best thing for premies to receive into their little tummies but even breastmilk doesn’t replace a placenta and only lessens the chance of NEC, it doesn’t always prevent it. Premies fed fresh breastmilk, which is full of anti-infective properties and epidermal growth factors as well as easily digested, do get NEC less often. BUT, this is further complicated by the fact that breastmilk alone is believed (with very strong evidence that is never the less compromised by the fact that the research was sponsored by
formla companies) by many researchers to be inadequate in terms of
protein,
calcium and
phosphorus for the adequate growth of a very small (less than 1500 gram) premie. So, even when
breastmilk is used it is often “
fortified”. The very act of fortifying the
milk renders it less protective against NEC because it is fortified with foreign and often irritating substances. For example, one common fortifier is called “Human milk fortifier” but it is not made from human milk, it is made from cow’s milk and other substances, which ARE ADDED TO human milk. A human milk fortifyer made from human milk needs to be developed. The very tiny premature infant may have a developmental
lactose intolerance (the
enzyme lactase develops late in gestation) and be unable to tolerate the milk sugar lactose. The most premature of the premature infants are more likely to get NEC and they are just the ones who also need more fortifications, a true “
catch 22”.
Causes other than feeding can also influence the development of NEC. Ischemia of the gut can occur as the body tries to protect the brain when blood pressure is low. Small bleeds or clots can obstruction circulation to the gut.
Trauma can occur as the result of other medical procedures. Epidemics of NEC do occur showing a transmissible
bacterial infection may sometimes be to blame. Even
full term babies can get NEC, although it is rare for this to happen.