Brain Death vs. Persistent Vegetative State: What's the Legal Difference?
By Melissa McCall, J.D. | Legally reviewed by Aviana Cooper, Esq. | Last reviewed June 01, 2023
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Brain death is a complex matter with an equally complex history. Before 1968, the definition of death was pretty standard. A person was dead once their cardiopulmonary system stopped working. In other words, when the heart and lungs stopped working, a person was dead. This changed after the first successful heart transplant in 1968.
Organ transplantation raised ethical issues about death. Was a person dead when their heart stopped beating, or did they die after surgeons removed their heart? Ventilators, feeding tubes, and other medical technologies have made it easier to sustain life after severe brain injuries.
Technology blurred the line between life and death. At what point is an individual legally declared dead?
The types of severe brain injuries that raise these problematic questions fall on the spectrum of persistent vegetative state and brain death.
A person medically declared brain dead (meaning there is zero brain activity) is legally dead. In brain death, there is an irreversible cessation of all functions of the entire brain. A person in a persistent vegetative state is unconscious, unaware, and unresponsive. A person can live in this state for years. Brain death, by contrast, is final.
Medical technology can keep brain-dead individuals on life support. At the same time, those in a persistent vegetative state (or "chronic wakefulness without awareness") may die naturally if this is in their living will. Organ transplantation adds to the urgency and stress of defining death. Surgeons must act quickly to harvest organs and tissue from organ donors.
Brain death is complex, but this article will help you understand the fundamental bioethics and legal implications of the most severe brain injuries.
Brain Death
Brain death is a legal and clinical conclusion. According to the American Academy of Neurology (AAN), brain death is "death by neurological criteria." There are many reasons a neurologist needs to declare someone brain dead officially.
It is challenging to understand a family member or loved one is dead if they are on life support in intensive care. They must decide about medical treatment, quality of life, and possible organ donation.
Biologically, the definition of brain death is simple. Brain death is the irreversible loss of all functions of the brain, including the brainstem (which controls breathing and other vital functions). Certain reflexes, such as spontaneous movement of limbs or sweating, often occur in brain-dead individuals. A brain death diagnosis has three main components:
- Coma: The patient is completely unresponsive and unconscious (typically tested with painful stimuli).
- Absence of Brainstem Reflexes: The patient is unresponsive to stimuli that otherwise would trigger an involuntary response (such as dilation of the pupils in the presence of a bright light).
- Apnea Test: When disconnected from a respirator, the patient should not have respiratory movements and will show other measurable signs supporting the diagnosis of brain death.
If a physician declares a patient is brain dead, he is clinically and legally dead. Life support will cease unless the patient is an organ donor. Brain-dead patients remain on life support to protect organs and tissues. If necessary, the patient remains on life support pending a second opinion.
Hospitals are not legally obligated to keep brain-dead patients on life support. Most state laws follow similar protocols. New York law, for instance, allows for limited "reasonable accommodations" for religious objections to the brain death standard. This exception applies to specific individuals, like next-of-kin.
The Uniform Determination of Death Act
The Uniform Law Commission finalized the Uniform Determination of Death Act (UDDA) in 1980. The purpose of the UDDA was to provide a uniform definition of death. The first successful heart transplant marked a turning point in determining death.
Before that surgery, life ended when a person's heart stopped beating. Heart transplantation raised new questions. Did life end when the heart stopped? Or did life end after the surgeon removed the heart?
The need to keep people alive grew in urgency as organ transplantation grew. Physicians could not ethically remove organs from living donors, even if they were on life support. Clinicians needed a way to determine death.
This issue had consequences outside of medical ethics. The determination of death impacts legal issues such as inheritance, life insurance, criminal law, and tort actions. The Uniform Determination of Death Act provided a model statute to determine death. Under the UDDA, the individual is legally dead when:
- Circulatory and respiratory functions irreversibly stop; or
- All functions of the entire brain irreversibly stop. The entire brain includes the brain stem.
The UDDA is a legal standard for defining death. The determination of death is different in clinical practice. In critical care settings, neurologists use medical criteria to conclude death.
Over 35 states and the District of Columbia have adopted the Uniform Determination of Death Act. New Jersey has not. In New Jersey, the heart and lungs cannot function without support before a declaration of death.
Brain Death Determination
Clinicians use neurological criteria to arrive at a determination of death. Using these criteria helps healthcare providers make difficult decisions. If a patient has no brain activity and is receiving life-sustaining treatment, a clinician will perform tests to determine if there is any brain function. The three markers of clinical brain death include:
- Unresponsiveness (including coma),
- No brainstem function, and
- Apnea or the inability to breathe on your own
There are different neurologic criteria in pediatrics. Before declaring a child brain dead, that child must receive two neurologic exams and two apnea tests. Two different physicians must perform these tests, with an observation period in between.
Once a neurologist determines that a person is brain dead, they can legally declare that person is dead. No one has ever recovered from brain death after these tests. This is true even if that person is on life-support machines.
Persistent Vegetative State?
An individual with severe brain damage or spinal cord injury in a chronic state of unconsciousness for at least four weeks is in a persistent vegetative state (PVS). PVS is often confused with a coma, but comatose patients are never conscious. It is also different from a minimally conscious state (MCS), where a person has minimal awareness of what is happening around them.
Coma, PVS, and MCS are three distinct disorders of consciousness. Disorders of consciousness apply to patients who regain consciousness after a brain injury.
After having undergone rigorous testing, a patient considered "highly unlikely" to live beyond a vegetative state is in a persistent vegetative state. PVS patients can recover higher brain functions. It is infrequent and largely dependent on the cause and nature of the brain injury. But recovery after three months is minimal.
Someone with PVS may exhibit limited wakefulness. This includes eye movements, spontaneous body movements, and groaning. PVS is a controversial diagnosis since patients with locked-in syndrome are fully conscious but similarly unable to communicate or respond to stimuli.
If there is no chance of recovery, family and loved ones may seek a court order to remove the patient from life support. But this is unnecessary if the patient or someone with power of attorney has signed a "do not resuscitate," or DNR, order. Without a court order or a DNR, the hospital must keep the patient alive through artificial means until further notice.
PVS, Brain Death, and Advance Directives
No one in a persistent vegetative state can express their wishes about life support. Creating a living will is the best way to dictate your end-of-life wishes.
A living will is a legal document that dictates a person's wishes in the event of an incapacity. What level of medical care do you want? Do you want to die naturally by removing the life-sustaining treatment or feeding tube? All parties are legally obligated to follow your wishes.
A durable power of attorney grants decision-making authority to a trusted individual named in the document. This person must adhere to your living will but legally may make other vital decisions not explicitly covered in the living will. Some states refer to this combination of a living will and durable power of attorney as an "advance directive."
Get Legal Help
The definitions of death are complex. Resources like Google Scholar and PubMed are helpful for a scientific understanding of these issues. An experienced local estate attorney can help you prepare for unexpected, catastrophic events. Legal documents, such as advance directives, give you and your loved one options. If you have questions about these differences, speak to a local healthcare attorney today.
Next Steps
Contact a qualified health care attorney to help navigate legal issues around your health care.