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What Does "Dead" Mean?

It should be obvious, but death has more than one definition

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


I recently took care of a baby admitted after a terrible brain injury. I knew the baby was dying. I told the parents one day, “I don’t see any signs that her brain is working. If her brain is dead, she is dead.” 

As I spoke those words, I couldn’t help but think it odd that I have to explain what it means to be dead. Shouldn’t it be obvious if someone is dead or alive?

It’s not always and there are at least two kinds of death. Circulatory death occurs when your heart stops working. Without circulating blood, vital organs don’t function. Brain death occurs when your brain stops working. The brain controls movements, thoughts, and personality. With modern technology a brain dead person can have a heartbeat, move in response to certain stimuli, and vital organs can function. To many, a brain dead person seems alive.


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Indeed it can be challenging to know if a person is brain dead. While guidelines exist for determining brain death in adults and children, debate continues about how to declare someone brain dead. A recent study of 492 hospitals published in the journal JAMA Neurology found differences in what kind of doctor could determine brain death, what kind of exams and tests are required, and how those exams and tests should be conducted.

To further complicate things, not everyone accepts that brain death means dead. Some sects of Judaism for example, teach that death occurs when someone stops breathing and doesn’t have a heartbeat. In New York and New Jersey, a brain dead person can be legally alive if the patient or family has religious objections to brain death.

These challenges have been front and center for teenager Jahi McMath was declared brain dead following cardiac arrest in December 2013. Recently, her family filed a federal lawsuit to have her death certificate revoked. McMath’s heart continues to beat. Her family believe she is alive.

As the controversy about who is dead and who is alive rages on, I think clinicians need to refocus their discussions to less academic, but more relevant issues to patients and families.

As a pediatric intensive care unit doctor, I regularly care for families of children with irreversible brain injury. I’ve seen parents decide to stop life support within days of an injury because the essence of what they considered a meaningful life for their child was gone. I’ve seen parents of a child who meets brain death criteria refuse to stop providing support, hoping for a miracle or not accepting the concept of brain death.

As a bioethicist, I encourage the philosophical conversation about what constitutes death. As a scientist, I support research that helps us better understand brain function. I realize that continuing to provide care for a brain dead person is costly, seemingly pointless to some, and can cause significant moral distress for care providers.

But as a doctor, I know that what is important for my patients and their families has little to do with definitions, technology, and money. What is important is building trust and focusing on each family’s values, beliefs and goals.

Trust is a major theme in an expanding literature that describes how clinicians can help families through challenging medical decisions encountered at the end-of-life or with critical illness. When a loved one’s life lies in the balance, trust is fundamental. Efforts to cultivate trust should drive discussions for dying patients.  

So what can you expect from your healthcare team to foster trust?

Clinicians need to use honest, direct, understandable, and frequent communication.

Clinicians should demonstrate genuine empathy.

Finally, clinicians should get to know each patient and family. Finding out from parents what their child was like before she got sick helps me develop a personal connection and understand what is important to that particular families.   

If you are caring for someone at their end of life, there are also things that you can to do foster trust with your clinicians.

Consider sharing information about your loved one. You can do this by telling stories about them or bringing in photographs.

Ask lots of questions. Clinicians strive to give understandable information, but feedback helps us know when our explanations fall short.  

Request a formal family meeting. Meetings allow you to hear from different doctors at simulateously and give you a forum for voicing your questions and concerns with fewer interruptions and distractions.

Finally, if you and your clinicians disagree about how to care for your loved one, ask for an ethics consults. In most hospitals, anyone can ask for an ethics consult, even patients and their families.

Determining death will likely always be controversial. But I believe that with trust, respect, and openness as the basis of decision-making conversations, families and clinicians can work together to make respectful and reasonable choices.