Hypothermia or low body temperature is used in patients, whose heart has stoppped and then was restarted. If the patient still remains unconscious, this usually means that the brain did not get enough oxygen during the time the heart was stopped.
If nothing is done to help out the brain other than usual measures such as giving oxygen and supporting normal vital signs, then the brain is more likely to be permanently injured. The result is a patient who survives CPR but is brain dead. Certainly, not a wished for result.
Low body temperature protects the brain by stabilizing and preserving brain cells. This allows for reversal of some of the injuries caused by lack of oxygen. Hypothermia is started as soon as possible after the heart is restarted. However, the temperature is lowered slowly so as to reduce side effects. The temperature is kept low enough until the danger period of brain injury is over, usually about 1 to 2 days.
At that point the patient’s temperature is slowly raised until normal. Results show that hypothermia treated patients are much less likely to suffer significant brain injury.
Hypothermia does-like virtually all treatments-have side effects. These include irregular heart beats, high blood sugar, low potassium and dehydration. In addition, clotting factors don’t work as well which can lead to increased bleeding, especially after trauma.
There are studies which suggest that this treatment of hypothermia may also work after head injury in which there is bleeding into the brain. However, for this type of patient the jury is still out.