Defining Death

February 7, 2014

Typically, in these posts my goal is to discuss the science behind a certain technique to help us understand the ethical issues surrounding the technique. With the recent case of Jahi MacMath, the thirteen-year-old girl who was declared brain dead after complications from tonsil surgery, rather than evaluating a new technology, it might be helpful to discuss the definition of brain death.

What is brain death?

Brain death is not to be mistaken for persistent vegetative state (PVS). When someone is diagnosed as being in a PVS, this means that the person does not have higher brain function, but maintains lower brain function. There is brain stem activity, which regulates involuntary actions such as breathing, circulation, and digestion. Someone in a PVS will undergo sleep-wake cycles and can respond to stimuli.

Coma is related to PVS in that it is due to a lack of higher brain function, and the person maintains brain stem activity. However, someone in a coma is not awake and does not respond to stimuli. Coma can often be temporary (Orr, 184).

Loss of higher brain function is different from whole-brain death or losing both higher and lower brain function. In this case (brain death) there is no brain function, even in the brain stem. All involuntary actions must be maintained by machines and medication. Whole brain death is only declared after a series of tests, which include physical tests, EEGs and imaging. In the U.S., different may states have different requirements, but typically, brain death must be determined by two different doctors at two different times. In Jahi McMath’s case, five physicians, two from the attending hospital and three chosen by the parents, declared her whole-brain dead.

The “traditional” definition of death is based on cardiopulmonary (heart-lung) function. If the heart stops pumping and there is no respiration, then the person is considered dead.   According to a statement from Jahi’s family in the Los Angeles Times, they will accept her death if her heart stops beating while she is on the respirator, but do not accept brain death as a valid criterion for death.

Whole-brain death was accepted as a definition of death in the 1970s, and is considered an accepted definition of death in all fifty states in the United States. This change was being considered in the 1950s when transplantation and prosthetics were becoming more commonplace. There was a move to change from a biological definition of death to a mental definition of death (Engelhardt, 242, 243). A person could lose all of his or her limbs, receive prosthetics and still be the same person. A person could receive a kidney, liver, heart, or lung transplant, all vital organs, and maintain his or her identity. The reasoning was that biological components must not be the only identifier of life and death.

However, the motivations behind changing the definition of death also came along because of organ transplantation and respirator technology. Once blood flow stops, there is a very narrow window of time in which organs can be removed from a person and transplanted to another patient. By allowing for brain death as a valid definition of death, blood and oxygen could be continued even if the patient is declared dead, until the organs can be transplanted. With the use of medical technology, the person’s body may appear to be normal, and they may seem to be “alive.” The historical reasons for the change in the definition of death (to facilitate organ retrieval) contribute to the discomfort many have with defining death based on brain function rather than heart and lung function.

Why is brain death controversial?

Often the controversy surrounding brain death involves patients who have lost higher brain function, but maintain brain stem activity. These are the stories that tend to make the news, including the rare cases where someone shows some recovery. One of the more famous cases was that of Terri Schiavo. She had lost higher brain function due to a heart attack, and was left in a persistent vegetative state. In PVS cases, the patient has certain, albeit minimized, interaction with the external world, and maintains certain bodily functions, making it very difficult to justify declaring this person legally dead.

Higher-brain death is more controversial because it places an arbitrary limit on the amount of brain activity that is necessary for one to be considered alive. Furthermore, prognosis is difficult because several factors contribute to whether the brain injury is truly permanent and how extensive it really is. A younger person is more likely to recover from traumatic brain injury than an older person. Someone who loses brain function due to lack of oxygen, as in Terri Schiavo’s case, is less likely to regain brain function compared to someone who sustained a traumatic brain injury. Additionally, the longer someone is in a PVS, the lower their chance of any recovery (Orr, 184-192).

Determining whole-brain death is less arbitrary than higher-brain death because the criteria includes that there is no discernable brain function. This is determined by a series of tests, including physical examination, responses to stimuli, voluntary respiration after being weaned from a respirator, and EEG and imaging data.

Whole-brain death is not without some controversy. First, occasionally EEG readings will show that some cells maintain activity but not the whole brain stem itself. This makes interpreting the EEG data a little more difficult. Additionally, whole-brain death involves making a distinction between biological death and mental death, even though a human being is both mind and body. Although the biological tissue is being kept alive by artificial means, to what extent must one be kept artificially alive to be considered technically dead? For example, a person with a pacemaker is being kept artificially alive by a machine, but we typically consider these people alive.

Bioethics Issues

Pediatric cases pose unique issues for bioethicists. The parents serve as the child’s surrogates, and in the case of Jahi McMath, the parents do not wish for their child to be taken off life support. A key bioethics question here is whether the parents have to accept whole brain death as the criterion for death. Furthermore, they cite religious reasons for not doing so. When it comes to matters of life and death, often certain allowances are made for various faith traditions.

Critics of Jahi’s parents argue that the doctors are not required to treat a futile case. In Jahi’s case, several other treatments must be in place in order for her body to continue on a ventilator. Because her brain stem is inactive, her body cannot do involuntary functions without the aid of other technology and medication. Some would maintain that measures, such as inserting a feeding tube would be inappropriate in this case, particularly because her body’s ability to digest food is severely limited. Others would consider a feeding tube basic care and therefore required, but would not consider it mandatory to resuscitate her heart, should she go into cardiac arrest.

Jahi’s case could also be a case of the difference between withholding life-saving treatment versus withdrawing treatment that is not benefiting a patient. While temporally the patient undergoes cardiopulmonary death (or cessation) after being removed from a respirator, the ethical question is what is the actual cause of death, assuming the family’s definition of cardiopulmonary death? Is it the removal of the respirator or is it the result of post-surgery complications? Additionally, is the point to hasten death, or is death inevitable, assuming cardiopulmonary definition of death. Even if this is the case, is the family required to remove their child from the respirator?

As of the writing of this article, Jahi McMath was transported to an undisclosed facility that will continue to keep her on life support as per the request of her parents. Reports on January 9 indicate that her body had deteriorated badly, but another report in CNN says that after receiving treatment at the new facility, she has stabilized. As of February 7, she is still on life support at the undisclosed location.


Engelhardt, H. Tristam, Jr. The Foundation of Bioethics, 2nd edition. New York: Oxford University Press, 1996.

Munson, Ronald. Intervention and Reflection: Basic Issues in Biomedical Ethics, 8th edition. Belmont, California: Thomas Higher Education, 2008.

Orr, Robert D. Medical Ethics and the Faith Factor: A Handbook for Clergy and Health-Care Professionals. Grand Rapids: Eerdmans, 2009.