Final answer:
The priority nursing action is to maintain hydration status with IV fluids.
Step-by-step explanation:
The priority nursing action for a terminally ill client with cancer who is receiving hospice services with an advance directive is to maintain hydration status with IV fluids.
In hospice care, the focus is on providing comfort and promoting quality of life. Hydration is essential to maintain the client's comfort and prevent dehydration, which can lead to various complications. IV fluids can be administered to ensure adequate hydration and support the client's overall well-being.
Monitoring airway status and preparing to assist with intubation, assisting with the administration of chemotherapeutic agents, and caring for elimination needs may not be appropriate or necessary in this situation, as they are more commonly associated with curative treatments rather than hospice care.