Soru

An $8$-year-old boy is evaluated on the pediatric ward for sudden onset of respiratory distress. He has a medical history significant for homozygous hemoglobin S disease. He was admitted $2$ days ago for a severe vaso-occlusive pain episode affecting his bilateral lower extremities, which has been managed with intravenous hydration and morphine. Today, he developed a new-onset fever with a temperature of $39.2^\circ\text{C}$, a respiratory rate of $32/\text{min}$, and sharp right-sided chest pain. Pulse oximetry shows an oxygen saturation of $87\%$ on room air. Physical examination reveals decreased breath sounds and crackles in the right lower lung field. Laboratory studies show that his hemoglobin level has dropped from a baseline of $8.2\text{ g/dL}$ to $6.1\text{ g/dL}$, and his leukocyte count is $18,500/\text{\mu L}$. A chest radiograph demonstrates a new right lower lobe consolidation. Which of the following is the most appropriate next step in the management of this patient?