Final answer:
The nurse's actions, including elevating the bed, checking pulse oximetry, and administering oxygen before notifying the physician, are best described by the term autonomy.
Step-by-step explanation:
The term that best describes the actions of the nurse who is caring for a patient who suddenly becomes acutely short of breath is autonomy. Autonomy in the healthcare context refers to the ability of the nurse to act according to their professional knowledge and judgment in response to a patient's immediate medical needs without direct physician orders at that moment. The nurse acted autonomously by elevating the patient's bed, checking pulse oximetry, and administering oxygen before notifying the physician, which are critical steps in managing acute respiratory distress.