Final answer:
The nurse should first ask for identification to verify if the person is authorized to view the patient's chart. Maintaining patient confidentiality is paramount; if the person isn't authorized, they must stop and the charge nurse should be informed.
Step-by-step explanation:
When a nurse on a med-surg unit in a large hospital observes an unfamiliar person looking at a patient's chart, the nurse's first course of action should be to ask for identification and determine if the individual has the right to view the chart. This is critical in maintaining patient confidentiality and adhering to hospital policies and the Health Insurance Portability and Accountability Act (HIPAA).
The nurse should approach the individual in a professional manner and inquire about their identity and purpose. If the person has a legitimate reason and the proper clearance to view the patient information, then they may continue. However, if the individual is not authorized, the nurse should request that they stop reviewing the chart and then immediately report the incident to the charge nurse, who will take further actions, such as possibly notifying security.