Final answer:
The nurse should assist the client in a sitting position for the administration of epidural anesthesia.
Step-by-step explanation:
In this situation, the nurse should assist the client in a sitting position for the administration of epidural anesthesia. The sitting position allows for easier access to the epidural space in the lower back, making the procedure more comfortable and effective for the client. Additionally, sitting can provide better support and stability for the client during the procedure.