The provisions of this Act are cumulative with existing law regarding an individual's right to consent or refuse to consent to medical treatment. The provisions of this Act shall not impair any existing rights or responsibilities that a health care provider, a patient, including a minor or a patient lacking decisional capacity, or a patient's family may have in regard to the withholding or withdrawal of life-sustaining treatment, including any rights to seek judicial review of decisions regarding life-sustaining treatment under the common law or statutes of this State to the extent they are not inconsistent with the provisions of this Act.
755 ILCS 40/55