Cool the body, save the brain

When Eldrid Primm went into cardiac arrest, his heart was saved with CPR, but what about his brain? Enter therapeutic hypothermia.

Eldrid Primm should be dead. He went into full cardiac arrest in January 2010.  University of Alabama at Birmingham emergency department staff worked feverously to save his life. After more than 90 minutes of CPR and treatment to dissolve a blood clot in his lung they succeeded.

Then the problem became saving Primm’s brain. When a person’s heart stops, oxygen-rich blood is no longer pumped to the brain, causing damage or death of brain cells. While the reasons are unclear, medicine has long known that the rapid return of blood to the brain following successful resuscitation carries with it the potential for additional damage to brain cells.

Enter UAB’s therapeutic hypothermia therapy, in which patients like Primm are cooled to a body temperature of 91.1 degrees Fahrenheit for 24 hours, then slowly rewarmed.

“The damage caused by rapid return of blood may be the result of overexcitement of neurons when oxygen is restored to the brain,” said Henry Wang, M.D., vice chair of research in the Department of Emergency Medicine. “Induced hypothermia slows the body’s metabolism and may help neurons better prepare for the return of oxygen by reducing that excitability.”