Review Question - QID 213728

A 47-year-old man presents to the hospital for a repeat right knee replacement. He has a history of lumbar radiculopathy and rotator cuff tendonitis for which he has been taking acetaminophen, gabapentin, methadone, and extended-release oxycodone. The patient obtains a femoral nerve block with a continuous infusion catheter and takes his usual dose of acetaminophen, gabapentin, methadone, and oxycodone. He undergoes the surgery under general anesthesia without significant events. In the post-anesthesia care unit, the patient complains of uncontrolled pain despite having received standard doses of fentanyl, hydromorphone, and oxycodone and having his nerve catheter started. His temperature is 98.6°F (37°C), blood pressure is 160/100 mmHg, pulse is 80/min, and respirations are 25/min. The right knee is braced without the appearance of significant localized edema or erythema. What is the most appropriate next step?