Nutrition and Fluids

Nutrition and Fluids in the NICU

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 have unstable health 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. This is 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
vital fluids and electrolytes through an IV (intravenous) tube in a vein. Some babies
may need a special fluid called parenteral nutrition (PN) or hyperalimentation. This has
nutrients they need until they are able to take milk feedings.

The contents of IV fluids and PN
are carefully tailored for each baby. The fluids have calories, protein, and fats. They
also have electrolytes. These include sodium, potassium, chloride, magnesium, and
calcium. Babies need calories, protein, and fats for healthy growth and development.
Fluids, electrolytes, and vitamins are needed for healthy working of the body’s

Blood tests help show how much of
each item a baby needs. The amount of each nutrient can be increased or decreased as
needed. Your baby’s weight and urine amount is tracked daily. This also helps to assess
fluid needs.

Watching your baby’s electrolyte and blood

Some babies have too much or too
little of certain electrolytes or other substances in the blood. As a result, some
common problems include:

  • Hypernatremia. This is high
    amounts of sodium (salt) in the blood.

  • Hyperkalemia. This is high
    amounts of potassium in the blood. It can be diagnosed by blood test. Or it can be
    diagnosed by changes in the baby’s heart rate pattern.

  • Hyperglycemia. This is high
    amounts of glucose (sugar) in the blood. It is diagnosed by blood tests, often
    done by heel stick. Some babies may need insulin to control high glucose

  • Hypoglycemia. This is low
    blood sugar. It is usually treated with IV fluids that have dextrose. This is a
    type of sugar.

  • Hypocalcemia. This is low
    calcium levels in the blood. It is 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 feedings
in very small amounts. This is done by tube feeding. These are called trophic
feedings. Trophic means that these feedings help the digestive tract mature and
grow. The amount of milk is very slowly increased over days or weeks. Once your baby is
able to have large enough amounts of milk feedings, IV fluids and PN can be slowly

Sick babies may not be strong
enough to suck well. 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. But small pacifiers for premature babies may
be used for comfort and practice when mothers aren’t available. It may help premature
babies to have drops of their mother’s colostrum by mouth even if they aren’t able to
feed by mouth yet.

Feeding your baby in the NICU

These are some ways babies may be
fed in the NICU:

  • Gavage or tube feedings.
    Premature babies, most often 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. It is then passed down into the
    stomach. The tube is usually left in place until the baby is able to feed by
    mouth ongoing. 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 gives 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 more than
    expected, it may mean the baby is not digesting milk well.

  • 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.

  • 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 likely 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. You will need to pay attention to your baby’s cues that show he or
    she is tired. 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. It 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 getting 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 has all the
nutrients needed for growth and development. Baby formulas you can buy are designed to
be close to human milk. But most of these 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, formula may not be as well tolerated by a baby.
Also, breastmilk has antibodies and other immune factors from the mother. These are to
help protect babies from infection. This is something that baby formulas you can buy
don’t have. This protection is extra important when babies are sick or premature and
have a higher risk of an infection. Necrotizing enterocolitis is a very dangerous
condition in very premature infants. It is more common in babies who don’t get
breastmilk. More breastmilk feedings also seem to lead to more brain growth for
premature babies.

Very premature babies may need
supplements added to breastmilk. This is done 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 for a short time
in addition to a baby’s own mother’s milk. Donor milk is pasteurized before it is given.
Because of this, it may lose some nutritional value. But it is more helpful 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 providers can help you and your
baby with breastfeeding. They can also teach you about pumping and storing your
breastmilk for your baby. Learning to feed by mouth is a process that can take babies
several weeks. Because of this, you will likely need to keep expressing milk even after
leaving the NICU.