A do-not-resuscitate order tells medical professionals that you do not want to receive CPR if your heart or lungs stop. Unlike other advanced directives that you can write yourself and have notarized, a DNR must be written by a doctor in your official medical chart. Requirements and instructions for the order vary by state.
When is it used?
DNR orders only pertain to stopping or preventing use of CPR, which can include mouth-to-mouth, breathing tubes, or electric shock to the heart. They don’t prevent the administration of pain medicine or first-aid.
Who can order it?
Your doctor writes a DNR order together with your consent. If you have named someone to speak for you, that person can consult with your doctor to write the orders. If you have not named anyone, and you are unable to speak for yourself, in some cases a loved one may agree to a DNR order on your behalf.
How do others know you have one?
You can, and should, tell your loved ones about your DNR instructions, and they can be included in your living will and any other documents that give instructions about your life. In the event of an emergency, you’ll want to carry instructions on your person so that emergency responders can abide by your wishes. DNR or Do Not Resuscitate can be engraved on your medical ID; however, there is no guarantee that an emergency responder will follow the DNR orders based solely on an ID engraving.
With a personal health record, you can upload your doctor’s official order so that emergency responders and other medical professionals can access it.
What if I change my mind?
If you decide you don’t want it, tell your doctor right away and remove it from any documents you keep personally. You always have the right to accept CPR, even if you have an existing DNR order.
Source: Medline Plus from the National Institutes of Health