What is a Living Will?
A Living Will is a declaration of how you prefer to be treated when death is imminent. It communicates your clear wishes to medical providers. Even though it has "Will" in its name, it is not related to a Last Will and Testament, which controls the distribution of assets after your death. A Living Will express your healthcare choices for your final moments, days, weeks... of life.
Difference from Health Care Power of Attorney
Firstly, this document only speaks when death is imminent due to a terminal condition. A Heath Care Power may be invoked when doctors do not think you can make sound decisions. This may be due to an accident or injury that temporarily limits your capacity to communicate.
Unlike your Health Care Power of Attorney, a Living Will does not appoint a person to make decisions for you. The document is given directly to medical staff that is caring for you. It is as if you are directly speaking with your healthcare provider, and telling them how you want to be treated. This may include orders of Do Not Resuscitate, pain management preferences, and other end of life decisions. However, this document is not as powerful as your Health Care Power. For example, it cannot direct your doctor to remove a feeding tube or water supply, if it will result in your death.
A Living Will is another piece of the Estate Planning puzzle. It is not a replacement for Powers of Attorney, but is useful if your healthcare agent is not available. Additionally, your Powers and Living Will must coordinate your wishes for end of life care. Conflicting language confuses your agent, medical staff, and introduces the potential for fighting amongst your loved ones.