Whole-Body Cooling

Hypoxic-ischemic encephalopathy (HIE) happens when a baby’s brain doesn’t get enough oxygen and blood flow around the time of birth. Whole-body cooling, also called therapeutic hypothermia, is a treatment for babies with HIE.

Whole-body cooling lowers your baby’s body temperature. At a lower temperature, the body needs less oxygen and energy. This helps to protect the brain and gives it time to heal.

How It Is Done

  • A special blanket that lowers your baby’s body temperature is used for treatment. The baby lies on the blanket and is wrapped in it.
  • The blanket can also warm your baby as needed so the baby does not get too cold.
  • You may be able to hold your baby during whole-body cooling (Picture 1).
  • A small temperature probe will be placed gently in your baby’s esophagus. This should not hurt. It measures the temperature inside the body, not the skin. The blanket temperature can be adjusted as needed.

An AI-generated image of a parent holding their baby in a whole-body cooling blanket

What to Expect

Whole-body cooling lasts for 3 to 4 days (72 to 96 hours), depending on when it was started. During treatment:

  • Your baby’s skin may look pale or blotchy.
  • Your baby may look asleep even when awake.
  • Your baby may shiver or feel cool. The baby may be given medicine to reduce shivering if needed.
  • You may be able to hold your baby for short periods of time. The baby must stay wrapped in the cooling blanket while being held.
  • Your baby cannot eat by mouth during whole-body cooling. Instead, they will be fed through a nasogastric (NG) tube. This small tube goes through the nose and into the stomach. You can pump milk for your baby to have through the tube or store for later.

Possible Risks

Sometimes, whole-body cooling may cause:

  • A slower-than-normal heart rate. This happens frequently and will be monitored.
  • Blood that doesn’t clot as well as usual. Your baby may be given medicine to prevent or control bleeding. This is also common but is monitored closely.
  • Red, reddish-brown, or purple lumps under the skin, called fat necrosis. This is not common. The lumps may be sore and usually go away within a few weeks or months. Tell your baby’s doctor or health care provider if you notice any lumps.

Checking Your Baby’s Brain Activity

Most babies have their brain activity watched (monitored) during cooling and until they are fully warmed. The care team uses an electroencephalogram (EEG) to record your baby’s brain activity and check for seizures. They will have small sensors placed on their head.

After Treatment

  • Your baby will slowly be warmed to a normal body temperature.
  • Your baby will have an MRI (magnetic resonance imaging) scan to look for signs of brain injury.

 

 

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