(a) Nothing in this article shall impair or supersede any legal right or legal responsibility which any person may have to effect the withholding of cardiopulmonary resuscitation in any lawful manner. In such respect, the provisions of this article are cumulative.
(b) Nothing in this article shall be construed to preclude a court of competent jurisdiction from approving the issuance of a do not resuscitate order under circumstances other than those under which such an order may be issued pursuant to the provisions of this article.