A client with metastatic cancer reports a pain level of 10 on a 0 to 10 scale. Twenty minutes after the nurse administers an IV analgesic, the client states, "No pain relief yet." Which intervention is most important for the nurse to include in this client's plan of care (POC)?

B Frequently evaluate the client's pain. A Replace transdermal analgesic patches every 72 hours. D Monitor client for break through pain. C Administer analgesics on a fixed and continuous schedule.