An Overview of Therapeutic Hypothermia

Clinically, therapeutic hypothermia (TH) has been used for over 70 years. However, it was first observed in ancient history where they realized hypothermia slowed the rate of bleeding.  TH has raised many controversies: is it beneficial? Do the risks outweigh any benefit? What is the safest way to administer TH? Throughout the years of research and controversy there are still many questions that remain.

 For those who are unfamiliar, TH is a medically-induced hypothermia.  The brain needs oxygen—it cannot survive without oxygen for more than 6 minutes.  When the brain is deprived of oxygen, a hypoxic brain injury ensues.  This can occur in instances of cardiac arrest when the heart is either not beating (either properly or not at all) or if a baby is having a difficult time passing through the birth canal and cannot transition from intrauterine to extrauterine life.  There are other instances of hypoxic brain injury but TH has proven most effective in these cases. Therapeutic hypothermia has shown to decrease the brain’s demand for oxygen by as much as 6% for every 1 degree Celsius the body temperature is lowered.  When TH is initiated after a hypoxic insult, there are fewer, sometimes no, long-lasting neurological effects.

 Patients who receive TH as a treatment are in a controlled environment, like an intensive care unit (ICU) although it can be initiated by a first responder or EMT.  TH is considered a high risk procedure due to the critical nature of the patients’ condition and also because of the side effects involved. Side effects include irregular heart rhythms, drops in blood pressure, increased risk of bleeding, fluid and electrolyte imbalances, and increased risk of pneumonia. If the patients’ wishes are unknown, it is up to the clinician’s expertise to determine whether or not the benefits outweigh the risks for that particular patient.

If you're curious about more information, you can find it here:
Neurologic Prognosis After Cardiac Arrest
Therapeutic Hypothermia: An old treatment gets a new look