A healthcare power of attorney (POA) authorizes someone to handle decisions regarding your healthcare on your behalf. An ordinary healthcare power of attorney expires the moment you become incapacitated (for example, if you were in a coma or under anesthesia). When a healthcare power of attorney is "durable," it means your agent's authority to act on your behalf continues even if you become incapacitated. Durable healthcare POAs are often used to prepare for a situation when important decisions need to be made, but you can't make them yourself. Having these documents in place helps eliminate confusion and uncertainty when family members have to make tough medical decisions.
If you become incapacitated and don't have a durable power of attorney, your family may have to go to court and have you declared incompetent before they can take make decisions on your behalf. So it's a good idea to have one in place - just in case.
Generally, you can choose any adult that you trust to be your agent - including your spouse, an adult son or daughter, an attorney, a parent, or another family member.
All types of healthcare POAs, including durable healthcare POAs, end when you pass away, so your agent will no longer have any legal authority.