(a) This chapter does not apply to:
(1) a decision to withhold or withdraw life-sustaining treatment from qualified terminal or irreversible patients under Subchapter B, Chapter 166;
(2) a health care decision made under a medical power of attorney under Subchapter D, Chapter 166, or under Subtitle P, Title 2, Estates Code;
(3) consent to medical treatment of minors under Chapter 32, Family Code;
(4) consent for emergency care under Chapter 773;
(5) hospital patient transfers under Chapter 241; or
(6) a patient's legal guardian who has the authority to make a decision regarding the patient's medical treatment.
(b) This chapter does not authorize a decision to withhold or withdraw life-sustaining treatment.