Skip to main content

Therapeutic Hypothermia

Medically reviewed by Last updated on Aug 31, 2022.

What is therapeutic hypothermia?

Therapeutic hypothermia is a procedure used to cool a person's body to a temperature that is lower than normal. The procedure is done after a cardiac arrest (when the heart stops) that happens outside of a healthcare setting. The unconscious person is cooled in the hospital after his or her breathing and heartbeat start again.

Why is therapeutic hypothermia done?

Therapeutic hypothermia is done to reduce the risk of brain swelling, blood clots, and seizures after cardiac arrest. The procedure may help the person survive.

How is therapeutic hypothermia done?

The therapeutic hypothermia process often begins with an IV of cold liquid to cool the person's body quickly. The person's body is slowly warmed 12 to 24 hours later. Several methods may be used to keep body temperature at a cooled level:

  • Ice packs, icy cold wet towels, or fans may be used. The ice packs are placed on the person's neck, armpits, torso, and groin.
  • A cooling blanket may be laid over the person's body. Cool water runs through the cooling blanket.
  • During endovascular cooling, a catheter is placed into a big vein in a person's groin. The catheter cools the blood as it passes through the vein and over the catheter.
  • During spinal cord perfusion, healthcare providers insert a constant flow of cooled saline into the spinal cord. The perfusion pump, suction device, and temperature probe keep the body at a constant temperature. It also keeps the spinal cord from swelling.
  • An epidural heat exchanger is a machine attached to a cooling catheter that is in the epidural space. The epidural space contains cerebrospinal fluid. The machine sends cool water into and out of the cooling catheter. The fluid stays cooled and keeps the spinal cord from swelling.

What happens during therapeutic hypothermia?

  • Healthcare providers will check the person's blood pressure, heart rate, and breathing rate throughout the process. Monitors in the person's esophagus, bladder, or rectum measure body temperature at all times. Healthcare providers will watch the person's temperature closely so it does not go too low or too high.
  • The person will start to shiver when the procedure begins. Shivering increases body temperature and decreases the benefits of therapeutic hypothermia. Healthcare providers will use medicines to stop the person from shivering. Healthcare providers may also use warm air in the room to help control shivering.

What are the risks of therapeutic hypothermia?

  • Effects of medicines given to prevent shivering may last longer than expected. Therapeutic hypothermia may cool the person too fast or to a temperature that is too low. Cooling may cause the person's blood pressure to become too high or too low. This can cause the heart to beat slowly or out of rhythm. Fluid loss from cooling can lead to dehydration or electrolyte (body chemical) levels that are out of balance. The medicines may prevent healthcare providers from realizing the person is having a seizure.
  • Cardiac arrest is life-threatening. Low blood pressure, seizures, coma, or brain death cannot always be prevented, even with therapeutic hypothermia treatment.

Care Agreement

The person has the right to help plan his care. He or she must learn about his or her health condition and how it may be treated. The person should discuss treatment options with his or her healthcare providers to decide what care he or she wants to receive. The person always has the right to refuse treatment.The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© Copyright IBM Corporation 2022 Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or IBM Watson Health

Learn more about Therapeutic Hypothermia

Care guides

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.