Final answer:
The first priority should be to address the patient's immediate and potentially life-threatening concerns by placing her in a room, performing an EKG, and alerting the physician immediately.
Step-by-step explanation:
The first priority when caring for a patient who presents with a heart rate of 50, respiratory rate of 24, and a blood pressure of 70/40, and denies chest pain but is experiencing arthritis discomfort should be to address the potential immediate life-threatening concern. Thus, the correct course of action would be to place her in a room, do an EKG, and notify the MD to see her first. Her vital signs suggest that she may be experiencing a form of shock or heart block, which requires urgent medical attention, and the EKG would help identify any cardiac abnormalities that need to be addressed promptly.