This clarity can aid in determining when the brain has absolutely and irreversibly stopped working.
You’re dead when the brain ceases functioning absolutely and irreversibly. It’s not always straightforward to draw the line between life and brain death. A new study aims to explain the distinction, potentially easing the pain of family members who have a loved one whose brain has died but whose heart continues to beat.
For decades, the idea of brain death has been accepted in medicine. However, according to Gene Sung, a neurocritical care physician at the University of Southern California in Los Angeles, there is a lot of difference in how people identify it.
“Showing that there is some worldwide consensus, understanding and agreement at this time will hopefully help minimize misunderstanding of what brain death is,” Sung says.
Sung and his colleagues convened doctors from professional societies around the world as part of the World Brain Death Project to forge a consensus about how to classify brain death. This group, which included critical care, neurology, and neurosurgery experts, reviewed the current literature on brain death (which was limited) and used their clinical experience to write the recommendations, which were published in JAMA on August 3rd. The final product also contained 17 supplements that addressed legal and religious issues, included checklists and flowcharts, and even traced the history of related medical advances. “Basically, we wrote a book,” Sung says.
“A fine, comprehensive clinical examination” is the bare minimum for deciding brain death, according to Sung. Before starting the test, doctors should make sure the person hasn’t had a neurological disorder or disease that could lead to brain death. The next step is for doctors to search for other causes, such as disorders that resemble brain death but are actually reversible. According to the study, cooling the body, which is used to treat heart attacks, can cause brain activity to temporarily vanish. Certain medications, alcohol, and other contaminants may do the same.
A brain death evaluation should involve a battery of measures for physical responses that necessitate the presence of a functioning brain, such as eye coordination, pain responses, and gag reflexes, among others. Physicians should also look to see whether a person tries to breathe on their own, which is a life-sustaining mechanism that relies on the brain stem. A individual can be considered brain-dead if none of these symptoms are present. Extra tests, such as those that look for blood flow or electrical activity in the brain, may be helpful, but the authors warn that interpreting them isn’t always easy.
Adults should undergo a single neurological test, whereas children should receive two, according to the guidelines. “Children can recover from a lot of different things differently from adults,” Sung says. “We want to really make sure they have had a devastating injury.”
According to Stanford University pediatric neurologist Paul Graham Fisher, clarity from medical practitioners on brain death has been long overdue. But, as he points out, that’s just the first move. “The snag is that the nonmedical part of the world has to buy in, too.”
According to Fisher, a straightforward and widely agreed concept of brain death is thwarted by complex cultural, theological, and even legal powers. “You’re still going to have people, on an individual level or a societal level, who may not buy in,” Fisher says.
He cites the example of Jahi McMath, an Oakland, California, teen whose parents refused to consider her brain death following complications from a tonsillectomy in 2013. For almost five years, she was on a ventilator and received tube feedings. According to a statement from her family’s counsel, her liver died in 2018.
Different areas and even hospitals have different guidelines for deciding brain death. Family members in New Jersey, for example, can object to a brain death determination based on religious or moral beliefs. A person can be brain-dead in Pennsylvania, Fisher points out, “but as soon as you cross the Delaware River, you can say, ‘I object to it.’”
Some nations have their own ways of doing things. Some doctors, for example, use brain scans to determine whether or not anyone is brain-dead. The guidelines can change as research progresses. “We can always learn more,” Sung says. “And if we learn more, we may have to change our recommendations.” But for now, “this is the best that we know.”