The agent need not have a medical background. It is common for spouses to name each other as health care agent and another person as backup agent. Some people name an adult child, sibling or friend. It's helpful to check with this person in advance to ensure they are comfortable taking on this responsibility.
After a doctor has found that you are unable to make or communicate medical decisions about your care, your healthcare agent will make medical decisions for you in the event you are unable to make those decisions for yourself. Typically the authority granted to your agent is quite broad and includes decisions pertaining to mental health as well as physical health. A doctor must comply with the decisions of the health care proxy or refer the patient to another doctor who will comply.
The reason to name a health care proxy is to ensure that you receive the type of care you would desire, as well as not receiving care that you would wish to decline, in the event you are unable to communicate your wishes yourself. Though not legally binding, many clients opt to create a nonbinding document - a living will or advance directive - which specifies their wishes in detail. A living will or advance directive provides information to your health care proxy to help guide their decisions about your care.
Often a living will or advance directive states your desire that your life not be artificially prolonged if you are dying. It can be helpful to your health care proxy to have this guidance on a very sensitive issue. Even though it isn't legally binding, it can provide valuable information about your wishes regarding end-of-life care, and can be especially helpful if there is disagreement among your family about what to do.
This is a legal document which permits your health care agent access to your medical records. Patient privacy laws make it critical to have a HIPAA Release. Without it your agent may be blocked from accessing information about your condition which they will need to make decisions for you.