(a) A living will or medical power of attorney may be revoked at any time only by the principal or at the express direction of the principal by any of the following methods:

1. (1) By being destroyed by the principal or by some person in the principal's presence and at his or her direction;

2. (2) By a written revocation of the living will or medical power of attorney signed and dated by the principal or person acting at the direction of the principal. Such revocation shall become effective only upon delivery of the written revocation to the attending physician by the principal or by a person acting on behalf of the principal.

   The attending physician shall record in the principal's medical record the time and date when he or she receives notification of the written revocation; or

3. (3) By a verbal expression of the intent to revoke the living will or medical power of attorney in the presence of a witness eighteen years of age or older who signs and dates a writing confirming that such expression of intent was made. Any verbal revocation shall become effective only upon communication of the revocation to the attending physician by the principal or by a person acting on behalf of the principal. The attending physician shall record, in the principal's medical record, the time, date and place of when he or she receives notification of the revocation.