Two tragic medical cases with the same outcome: patients brain dead and on life support.
For 13-year-old Jahi McMath of Oakland, California, brain death was declared in the wake of complications from surgery. Her parents have fought to keep her on life support, contending that the functioning of her heart and lungs indicates she is still alive. In Texas, Marlise Munoz, a 33-year-old pregnant woman, collapsed at home and was subsequently termed brain dead at the hospital, according to her family. She remains on life support despite family wishes to turn off the ventilator; the hospital says it is following a state statute that prohibits removing life support from a pregnant patient so as to maintain the viability of the fetus.
Despite their differences, these cases raise a common question: What does "brain death" actually mean?
National Geographic spoke to experts in neurology and in biomedical ethics to explain why the definition is central to understanding the controversies that have arisen in each instance.
What does it mean to be brain dead?
The commonly accepted definition of brain death-also referred to as death by neurological criteria-is "the irreversible cessation of all activity in the cerebral hemispheres and the brain stem," says Robert Stevens, associate professor of Neuroscience Critical Care at Johns Hopkins University School of Medicine.
Bottom line: "Brain death is death," says Richard R. Sharp, director of the biomedical ethics program at the Mayo Clinic. "Even among medical students and clinicians you will find misunderstanding. But from a medical and legal point of view, brain dead means dead."
Why is the term so confusing to so many people?
The term is a product of modern medicine, Stevens says, where machines (such as ventilators) can continue to provide oxygen even after devastating neurological injury. By contrast, in the past, neurological, cardiac, and pulmonary death would occur in close succession. In other words, once the brain is dead, the heart and lungs would soon stop functioning as well.
Today, however, "you can be brain dead, with an irreversible cessation of all activity in the brain," but because of the artificial situation of being on a ventilator, the heart is still beating. There may be reflex movements of the legs or the arms. "And the family members will say, This does not look they are brain dead." But they are.
What do you do to confirm brain death?
"We go to great pains to confirm that," says Stevens, and to ensure that there are no reversible conditions.
"There are very specific neurological tests at the bedside, and you have to go through those tests twice, six hours between the two tests in adults; 24 hours between the two tests for children."
Can people recover from brain death? There are stories that claim such reverses.
"There is no possibility of recovering from brain death," says Stevens. "Brain death recovery suggests a misdiagnosis. If you recovered, it was something else"-possibly a coma or vegetative state. Too often, people confuse those situations with brain death, says Sharp.
How do they differ?
"Coma is distinguished from brain death by the fact that you can elicit responses from the brain, detect movements in response to pain, and it is not irreversible," says Stevens. "You can wake up from a coma." The term vegetative state refers to patients "who have a severe impairment of consciousness but have progressed to a state where they begin to open their eyes. In medical speech we say that they have elements of arousal but there is no awareness." This condition also has the potential for reversal.
Do you anticipate any developments dealing with brain death cases as a result of these two patients?
First of all, says Stevens, both cases demonstrate the need for the medical community to do a better job of explaining what brain death means, to work closely with the families, and to "communicate in clear and unambiguous terms" what is happening and what needs to be done.
In addition, says Cynda Rushton, Bunting Professor of Clinical Ethics at the Johns Hopkins Berman Institute of Bioethics, "all of us in the medical community need to pause and reflect on what we can learn-how to provide care that is both compassionate and respectful but also that clearly communicates the limits of what medicine can and cannot do. And it's hard for all of us to accept those limits because we have so much promise in our technology, and we have become so seduced by it that we actually think that it can correct things that are not possible to be corrected."
Finally, the California case suggests the need for hospitals "to have a formal hospital policy in place to deal with a family's request for care after brain death has been declared," says Sharp. Such a policy would state how much time would be allowed for the family to grieve with the deceased family member or to find another place to transfer, he says.
What can you say to grieving family members to explain what brain death means and to help them decide whether to continue or cease medical care?
"These situations are tragic and are very emotional and very difficult for everyone," says Rushton. "And what we need to say is, first of all, we're really sorry that despite all of our knowledge and technology we weren't able to correct the situation, to intervene in that process. We weren't successful, and we tried our best, as did everyone. And everyone really does pull out all the stops to save a life-but when we're not able to do that, we have to be honest that we have not been successful, that the person has died. It's always hard to accept that death has occurred. And yet one of the greatest gifts we can give people is to help them navigate through that process with as much kindness and support as possible."