If your baby has a condition called hypoxic-ischemic encephalopathy (HIE), this means that your baby’s brain has been deprived of oxygen before, during and/or after delivery. The seriousness of HIE depends on how long your baby was without oxygen, the affected area of your baby’s brain and how developed your baby’s brain cells are. HIE is an injury that can develop over the next few hours to days.

There are three categories of HIE: mild, moderate and severe. Most babies that have mild HIE recover with no disability. About 40-70 percent of babies with moderate HIE have some form of lifelong disability like cerebral palsy, impaired brain function and seizures. The most severe cases almost always result in severe disabilities that may include mental retardation, severe motor dysfunction and seizures. Severe HIE can also cause death. Your baby’s doctor will talk with you about how severe your baby’s HIE is, and what to expect in the days and weeks ahead.

Most of the time, the cause of HIE is unknown. Bleeding or problems with the mother’s uterus, the placenta or umbilical cord could cause HIE.

Babies who have HIE may develop problems with breathing, bleeding and with their heart, liver and kidneys because of the lack of oxygen and blood to these organs. Some of these problems may need treatment right away. When the brain injury is moderate or severe, your baby can have seizures, and later in childhood can have problems learning, thinking and speaking (called cognitive problems). They can also have problems with walking or coordination, sometimes seen as cerebral palsy (called motor problems).

At CHOC, we use brain and whole body cooling, also called hypothermia treatment, to slow down a baby’s body and brain so they can recover. This technique has been proven to minimize the effects of HIE. Treatment must begin within six hours of birth. We offer two types:

• Blanketrol® III Whole Body Cooling System: Your baby will lie on a special cooling blanket that has water running through it. The water temperature can be adjusted to warm or cool the body. Normal body temperature is 98.6°F (37°C). Your baby will be maintained in a range between 91°F -95°F (32.5°C-35°C) during the cooling process.
• Olympic Cool-Cap System: Your baby will wear a special hat (like a swimming cap) that has water running through it. The water temperature can be adjusted to warm or cool the body. Your baby will be maintained in a range between 92°F -95°F (33.5°C-35°C) during the cooling process.

A thermometer will be put into your baby’s throat or bottom to continuously monitor his/her body temperature. The cooling treatment will last for 72 hours, or three days. We will then rewarm your baby over the next four to 12 hours, depending on which treatment is used.

Your baby may need medicine and blood products to treat seizures, potential infection, blood pressure and to keep your baby calm. He or she may need the help of a breathing machine, and special IV access for monitoring, treatment and nutrition. There will be no milk feeding during treatment.

Your baby’s skin may be pale or blotchy and may feel cool to the touch. You may not be able to hold your baby in your arms because it may increase the baby’s temperature. The treatment is noninvasive and is monitored closely to be sure that the baby is comfortable.

Not all babies experience side effects from the treatment, although there are two temporary side effects that can be expected. The first is a minor cardiac arrhythmia, called a sinus brachycardia—which means the baby has a slow heartbeat. It is a very common when anyone, not just a newborn baby, has hypothermia. The second common side effect is edema (or swelling) of the head and scalp. This kind of swelling normally goes away by itself, or with scalp massage and repositioning.

Your baby will have testing done to assess brain function.

• An electroencephalogram (EEG) after treatment will look at the brain’s electrical activity and possible signs of seizures that are common in babies with HIE.
• Brain imaging (MRI) will evaluate the brain’s structure and extent of brain injury.

Your baby will stay in the NICU until ready to go home. Your baby will need close developmental follow-up care after discharge—which will also help us collect information about development of babies with HIE.