New AAN guideline provides step-by-step process for determining brain death in adults

In an effort to create a uniform and accurate method for determining brain death, the American Academy of Neurology has issued an updated guideline that provides doctors with a step-by-step process for determining brain death in adults. The guideline is published in the June 8, 2010, issue of Neurology®, the medical journal of the American Academy of Neurology.

"The new AAN guideline is an improvement over the 1995 guideline and examines recent studies on clinical determination of brain death," said lead guideline author Eelco Wijdicks, MD, PhD, with the Mayo Clinic in Rochester, Minn. and Fellow of the American Academy of Neurology. "The brain death diagnosis can be made only after a comprehensive clinical evaluation and often involves more than 25 separate assessments. The new guideline includes a checklist that will help doctors with this diagnosis."

Brain death is the permanent loss of brain function and means the person has died. The only way to keep the lifeless body working is through intensive care support. Brain death can result from a severe traumatic brain injury, stroke or prolonged CPR after cardiac arrest. No further medical support is needed unless the person's organs can be donated.

According to the guideline, there are three signs that a person's brain has permanently stopped functioning. First, the person is comatose, and the cause of the coma is known. Second, all brainstem reflexes have permanently stopped working. Third, breathing has permanently stopped. A ventilator, or breathing machine, must be used to keep the body functioning.

The guideline describes several complex steps doctors must follow to diagnose brain death. It carefully reviewed the best way to demonstrate absence of breathing. The guideline also concludes that laboratory tests such as EEG or cerebral flow studies are not needed to come to a diagnosis. The guideline also makes clear that this complex process must be completed by a doctor with considerable skill and experience in diagnosing brain death.