Review Question - QID 213872

A 9-year-old boy presents to the pediatric emergency department for right lower extremity pain. The patient describes the pain as severe and sharp in nature. He developed the pain, which has yet to subside, a few hours prior to presentation, and he denies any trauma to the lower extremities. He endorses participating in intense sports and has not been drinking fluid during sports. He has had similar episodes in the past; however, the pain affected his back when he was 4-years-old and his chest when he was 6-years-old, requiring admission for pain management with intravenous morphine. Family history is remarkable for his father requiring hospitalization for acute and severe painful episodes. Additionally, his father passed away secondary to myocardial infarction. On physical examination, the patient appears uncomfortable but is cognitively intact. He has tenderness upon palpation of the right lower extremity. The extremity is mildly warm without evidence of erythema. Distal pulses are present. Confrontational motor strength testing is grossly normal although limited by pain. His sensory examination is unremarkable. Laboratory studies are remarkable for a hemoglobin of 8 g/dL and a hematocrit of 21%. A blood smear is demonstrated in Figure A. Which of the following is the most appropriate intervention to decrease the risk of developing a future acute painful episode in this patient?