In many states you need a separate document, a health care power of attorney, that meets specified legal criteria to grant a person a power of attorney to make health care decisions for you in the event you become incompetent or incapacitated. The agent you appoint, sometimes called a health care proxy, typically has the ability to act when your doctor deems that you are unable to make decisions regarding your treatment. Even if you are young and healthy, it is wise to establish a health care power of attorney to facilitate the medical process in what might be a very stressful time. Without this direction, your doctor typically would turn to your closest relative to make decisions on your behalf. Having a health care power of attorney in place can help avoid involving a court if relatives cannot agree on your care.
You may also want to consider establishing an advance health care directive that clearly explains your health care preferences to your physician and family members. This document should specify the kinds of medical treatment you want—or don't want—if you are unable to speak for yourself. The directive would include your wishes about using or not using life-sustaining procedures in any situation. Be aware that your state of legal residence may have specific requirements for your directives to be effective, so you should consult with your estate planning attorney.