DNR - Do Not Resuscitate Orders

Also often called a "no code," a DNR is placed on a patient's medical chart to indicate there should be no attempt to restart a failed heartbeat or restore breathing by any means such as by using CPR (cardiopulmonary resuscitation), a ventilator, electrical stimulation, or use of medications for this purpose. A DNR order can be changed and experts say it should be reviewed regularly.

See
American Medical Association DNR Orders
British Medical Association Doctors Want Rule Change on Resuscitation
DNR -- Do Not Resuscitate Orders -- Q & A for Patients