A Power of Attorney is a legal document giving another person (the attorney-in-fact) the legal right to do certain things for you. What those rights, or powers, are depends on the terms of the document. A Power of Attorney may be very broad or very limited and specific. All Powers of Attorney terminate upon the death of the maker. They may also terminate when the maker becomes incapacitated.
When the intent is to designate a decision-maker in the event of your incapacity, a Durable Power of Attorney should be used. Durable Powers of Attorney should be frequently updated because banks and other financial institutions may hesitate to honor a Power of Attorney that is more than a few years old.