(a) A competent qualified patient who is an adult may issue a directive by a nonwritten means of communication.
(b) A declarant must issue the nonwritten directive in the presence of the attending physician and two witnesses who qualify under Section 166.003, at least one of whom must be a witness who qualifies under Section 166.003(2).
(c) The physician shall make the fact of the existence of the directive a part of the declarant's medical record, and the names of the witnesses shall be entered in the medical record.