Nutrition and Fluids
Nutrition for babies in the NICU
Feeding babies in the NICU is quite different from feeding healthy babies. When babies
are sick or premature, they are often not well enough to breastfeed or take a bottle.
Premature babies may not be able to suck effectively, or their GI (gastrointestinal)
tracts may not be mature enough to digest feedings. Babies who are medically unstable
are often unable to take regular feedings. Babies with umbilical catheters and those
who need help breathing, such as with a mechanical ventilator, may not be able to
be fed because of the risk of problems such as aspiration (breathing food into the
lungs).
IV fluids and parenteral nutrition
Many babies in the NICU receive essential fluids and electrolytes through an IV (intravenous)
tube in a vein. Some babies may need a special preparation called parenteral nutrition
(PN) or hyperalimentation, which has nutrients they need until they are able to take
milk feedings.
The contents of IV fluids and PN are carefully calculated for each baby. Calories,
protein, fats, and electrolytes including sodium, potassium, chloride, magnesium,
and calcium are all important components. Babies need calories, protein, and fats
for adequate growth and development. Fluids, electrolytes, and vitamins are needed
for proper functioning of the body's systems.
Blood tests help determine how much of each component a baby needs and the amount
of each nutrient can be increased or decreased accordingly. Daily weights and keeping
track of a baby's urine output also help monitor fluid needs.
Monitoring your baby's electrolyte and blood levels
Some babies have too much or too little of certain electrolytes or other components
in the blood. As a result, some common problems include the following:
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Hypernatremia. High amounts of sodium (salt) in the blood.
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Hyperkalemia. High amounts of potassium in the blood; can be diagnosed by blood test, or by changes
in the baby's heart rate pattern.
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Hyperglycemia. High amounts of glucose (sugar) in the blood; diagnosed by blood tests, often done
by heel stick; some babies may need insulin to control high glucose levels.
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Hypoglycemia. Low blood sugar; usually treated with IV fluids containing dextrose (another form
of sugar).
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Hypocalcemia. Low calcium levels in the blood; usually treated with calcium in IV fluids.
Is your baby ready for milk feedings?
Even babies younger than 28 weeks gestation can benefit from milk feedings. Very early
preterm infants are given trophic feedings in very small amounts by tube feeding.
Trophic means that these feedings help the digestive tract mature and grow. The amount
of milk is very slowly increased over days to weeks. Once your baby is able to handle
large enough amounts of milk feedings, IV fluids and PN can be slowly decreased.
Sick babies may not be strong enough to suck effectively. Premature babies may not
be physically mature enough to coordinate sucking, swallowing, and breathing. Or they
may be too weak to suck for long periods of time. Sucking is the earliest sign that
a baby is getting ready to practice feeding by mouth. It also has a calming effect. The
best place for the baby to practice sucking and learn to feed is at the mother’s breast. However
small pacifiers designed for premature babies may be used for comfort and practice
when mothers aren't available. It also seems to be helpful for premature babies to
have drops of their mother's colostrum by mouth even if they aren't mature enough
to feed by mouth.
Feeding your baby in the NICU
The following are some ways babies may be fed in the NICU:
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Gavage or tube feedings. Premature babies, especially those younger than 32 to 36 weeks gestation, often can’t
be fed from the breast or bottle. Gavage or tube feedings may be needed until the
baby learns to suck well. For gavage feedings, a small flexible tube is placed into
a baby's nostril or mouth and passed down into the stomach. The tube is usually left
in place until the baby is consistently able to feed by mouth. At first, tiny amounts
of breastmilk or formula are given through the feeding tube. Because of their small
stomach size, very tiny babies may be fed using a pump that slowly delivers the milk
in small amounts. As the babies grow, they are able to slowly take larger amounts
at each feeding. Before each tube feeding, a baby may be checked for residual. This
is the amount of milk in the stomach left over from the last feeding. If the amount
of residual is higher than expected, it may mean the baby is not digesting food well.
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Cup or spoon feedings. Some NICUs use soft flexible feeding cups or shallow feeding spoons instead of bottles
for babies who are learning to breastfeed.
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Nipple feedings. Feeding practice from breast or bottle can begin as soon as babies are stable and
are able to suck well. Your baby will probably begin to practice feeding by mouth
while still being tube fed. Even if a baby shows interest and participates in a feeding,
it can be tiring. It is always important to pay attention to behavioral cues that
show tiredness. If you are using a bottle, it’s important to help your baby pace the
feeding. Learning to feed by mouth is a gradual developmental process that can take
several weeks for premature babies. So it’s normal to take only occasional small amounts
by bottle or at the breast. To find out how much milk a baby is transferring at the
breast, he or she can be weighed before and after the feed using a special scale. As
your baby increases the amount he or she can safely and comfortably take by nipple,
the amount in the tube feedings can be decreased.
Why breastmilk is important and how lactation consultants can help
A mother's milk is the preferred milk for all babies, especially the most premature
babies. Breastmilk contains all the nutrients needed for growth and development. Although
commercial formulas are designed to be close to human milk, most are based on cow's
milk protein. This is different from human protein. The proteins and fats in breastmilk
are more easily digested. Because of these differences in digestion, formula may not
be as well tolerated. In addition, breastmilk contains antibodies and other immune
factors from the mother to help protect babies from infection. This is something that
commercial formulas don’t have. This protection is especially important when babies
are sick or premature and have higher chances of developing an infection. Necrotizing
enterocolitis, an especially dangerous condition in very premature infants, is more
common in babies who don't receive breastmilk. In the longer term, more breastmilk
feedings seem to lead to more brain growth for premature babies.
Very premature babies may need supplements added to breastmilk to meet their increased
needs for protein, calcium, and phosphorus. Even if your baby can’t breastfeed, you
can pump your breastmilk and it can be stored for gavage or nipple feedings. Depending
on the amount of milk needed for feedings, donor milk or formula may need to be given
temporarily in addition to a baby's own mother's milk. Donor milk is pasteurized before
it is given and may lose some nutritional value. But it is more beneficial for premature
infants than formula. It is an important option when the mother's breastmilk is not
available.
Certified lactation consultants (IBCLC) are nurses or other healthcare providers who
are specially trained and certified to help women with breastfeeding. In the NICU,
these professionals can help you and your baby become comfortable nursing. They can
also teach you about pumping and storing your breastmilk for your baby. Because learning
to feed by mouth is a process that can take babies several weeks, you will likely
need to keep expressing milk even after leaving the NICU.