Section 404.850 - Revocation, procedure, effect1. A power of attorney for health care may be revoked at any time and in any manner by which the patient is able to communicate the intent to revoke. Revocation shall be effective upon communication of such revocation by the patient to the attorney in fact or to the attending physician or health care provider.2. Upon learning of the revocation of a power of attorney for health care, the attending physician or other health care provider shall cause the revocation to be made a part of the patient's medical records.3. Unless the power of attorney provides otherwise, execution by the patient of a valid power of attorney for health care revokes any prior power of attorney for health care.