Final answer:
The circulating nurse should proceed with the setup for surgery and have the surgeon document that the case is emergent.
Step-by-step explanation:
According to the provided information, the family of the unconscious trauma patient is two hours away but on the way. In such a situation, the circulating nurse should not wait for the family to arrive and sign the consent for surgery. It is crucial to prioritize the patient's life-saving surgery. The appropriate action for the nurse would be to have the surgeon document that the case is emergent and proceed with the necessary setup for surgery.