Advance directive. A general term that describes two kinds of legal documents, living wills and medical powers of attorney. These documents allow a person to give instructions about future medical care should he or she be unable to participate in medical decisions due to serious illness or incapacity. Each state regulates the use of advance directives differently.

Artificial nutrition and hydration. Artificial nutrition and hydration (or tube feeding) supplements or replaces ordinary eating and drinking by giving a chemically balanced mix of nutrients and fluids through a tube placed directly into the stomach, the upper intestine or a vein.

Benefits and burdens. A commonly used guideline for deciding whether or not to withhold or withdraw medical treatments. A benefit can refer to the successful outcome of a medical procedure or treatment. Outcomes can be medical (e.g. the heart beats again) or functional (e.g. the person is able to walk to the bathroom after being incapacitated by a stroke), or it supports the patient’s values (for example, the patient is able to die at home as he wished). However, a benefit from one point of view can be experienced as a burden from another and might be viewed differently by doctors, patients and families. For example, if a patient is resuscitated and the heart starts beating again, this is a successful outcome from a medical point of view and a doctor may consider it a benefit. To the patient who is dying from a serious illness or disease, resuscitation may cause further injury and only contribute to the overall experience of suffering. This success, from the doctor’s point of view, might actually be experienced as an additional burden by the patient. Discussions of the benefits and burdens of medical treatments should occur within the framework of the patient’s overall goals for care.

Bereavement. The period after a loss during which grief is experienced. The time spent in a period of bereavement depends on how attached the person was to the person who died, and how much time was spent anticipating the loss.

Best interest. In the context of refusal of medical treatment or end-of-life court opinions, a standard for making health care decisions based on what others believe to be "best" for a patient by weighing the benefits and the burdens of continuing, withholding or withdrawing treatment. (Contrast with "substituted judgment.")

Brain death. The irreversible loss of all brain function. Most states legally define death to include brain death.

Capacity. In relation to end-of-life decision-making, a patient has medical decision making capacity if he or she has the ability to understand the medical problem and the risks and benefits of the available treatment options. The patient’s ability to understand other unrelated concepts is not relevant. The term is frequently used interchangeably with competency but is not the same. Competency is a legal status imposed by the court.

Cardiopulmonary resuscitation. Cardiopulmonary resuscitation (CPR) is a group of treatments used when someone’s heart and/or breathing stops. CPR is used in an attempt to restart the heart and breathing. It may consist only of mouth-to-mouth breathing or it can include pressing on the chest to mimic the heart’s function and cause blood to circulate. Electric shock and drugs also are used frequently to stimulate the heart.

Clear and convincing evidence. A high measure or degree of proof that may be required legally to prove a patient’s wishes. A few states require clear and convincing evidence that an incompetent patient would want to refuse life-support before treatment may be stopped unless the patient has completed an advance directive authorized by the state's law.

Do-Not-Resuscitate (DNR) order. A DNR order is a physician’s written order instructing health care providers not to attempt cardiopulmonary resuscitation (CPR) in case of cardiac or respiratory arrest. A person with a valid DNR order will not be given CPR under these circumstances. Although the DNR order is written at the request of a person or his or her family, it must be signed by a physician to be valid. A non-hospital DNR order is written for individuals who are at home and do not want to receive CPR.

Emergency Medical Services (EMS). A group of governmental and private agencies that provide emergency care, usually to persons outside of health care facilities; EMS personnel generally include paramedics, first responders and other ambulance crew.

Euthanasia. The term traditionally has been used to refer to the hastening of a suffering person's death or "mercy killing". Voluntary active euthanasia involves an intervention requested by a competent individual that is administered to that person to cause death, for example, if a physician gives a lethal injection with the patient’s full informed consent. Involuntary or non-voluntary active euthanasia involves a physician engaging in an act to end a patient’s life without that patient’s full informed consent. See also Physician-hastened Death (sometimes referred to as Physician-assisted Suicide).

Grief. Grief is how one reacts to a loss. Grief reactions may be experienced in response to physical losses, such as death or in response to social losses such as divorce or loss of a job. All loss involves the absence of someone loved or something that fulfills a significant need in one’s life.

Guardian ad litem. Someone appointed by the court to represent the interests of a minor or incompetent person in a legal proceeding.

Incompetent. See "Capacity."

Healthcare agent. The person named in an advance directive or as permitted under state law to make healthcare decisions on behalf of a person who is no longer able to make medical decisions.

Hospice care. A program model for delivering palliative care to individuals who are in the final stages of terminal illness. In addition to providing palliative care and personal support to the patient, hospice includes support for the patient’s family while the patient is dying, as well as support to the family during their bereavement.

Intubation. Refers to "endotracheal intubation" the insertion of a tube through the mouth or nose into the trachea (windpipe) to create and maintain an open airway to assist breathing.

Legislation. Laws enacted by state or federal representatives.

Life-sustaining treatment. Treatments (medical procedures) that replace or support an essential bodily function (may also be called life support treatments). Life-sustaining treatments include cardiopulmonary resuscitation, mechanical ventilation, artificial nutrition and hydration, dialysis, and certain other treatments.

Living will. A type of advance directive in which an individual documents his or her wishes about medical treatment should he or she be at the end of life and unable to communicate. It may also be called a “directive to physicians”, “health care declaration,” or “medical directive.” The purpose of a living will is to guide family members and doctors in deciding how aggressively to use medical treatments to delay death.

Mechanical ventilation. Mechanical ventilation is used to support or replace the function of the lungs. A machine called a ventilator (or respirator) forces air into the lungs. The ventilator is attached to a tube inserted in the nose or mouth and down into the windpipe (or trachea). Mechanical ventilation often is used to assist a person through a short-term problem or for prolonged periods in which irreversible respiratory failure exists due to injuries to the upper spinal cord or a progressive neurological disease.

Medical power of attorney. A document that allows an individual to appoint someone else to make decisions about his or her medical care if he or she is unable to communicate. This type of advance directive may also be called a health care proxy, durable power of attorney for health care or appointment of a health care agent. The person appointed may be called a health care agent, surrogate, attorney-in-fact or proxy.

Non-hospital DNR Order. A physician's order that directs emergency medical providers and other healthcare workers not to attempt CPR for persons being cared for at home. Laws and regulations governing their use vary from state to state.

Palliative care. A comprehensive approach to treating serious illness that focuses on the physical, psychological, spiritual, and existential needs of the patient. Its goal is to achieve the best quality of life available to the patient by relieving suffering, by controlling pain and symptoms, and by enabling the patient to achieve maximum functional capacity. Respect for the patient’s culture, beliefs, and values are an essential component. Palliative care is sometimes called “comfort care” or “hospice type care.”

Respiratory arrest. The cessation of breathing - an event in which an individual stops breathing. If breathing is not restored, an individual's heart eventually will stop beating, resulting in cardiac arrest.

Surrogate decision-making. Surrogate decision-making laws allow an individual or group of individuals (usually family members) to make decisions about medical treatments for a patient who has lost decision-making capacity and did not prepare an advance directive. A majority of states have passed statutes that permit surrogate decision making for patients without advance directives.

Withholding or withdrawing treatment. Forgoing life-sustaining measures or discontinuing them after they have been used for a certain period of time.