Final answer:
The nurse is acting as the patient's advocate by supporting and promoting their best interests and wishes.
Step-by-step explanation:
The nurse is acting as the patient's advocate. An advocate is someone who supports and promotes the best interests and wishes of another person. In this case, the nurse is advocating for the patient's desire to go home on oxygen and be comfortable, while also discussing the risks and benefits of the surgical procedure with the family. The nurse serves as a liaison between the patient and the family, ensuring the patient's wishes are respected and understood.