Tenn. Code Ann. § 34-6-210

Nothing in this part authorizes an attorney in fact to consent to the withholding or withdrawal of health care necessary to keep the principal alive, if the principal objects to the withholding or withdrawal of the health care. In that instance, that health care decision shall be governed by the law that would apply if there were no durable power of attorney for health care; however, with respect to other and subsequent health care decisions, the durable power of attorney for health care shall remain in effect unless expressly revoked as provided in § 34-6-207.