A 32-year-old, 70-kg man with sickle cell disease is admitted to the ICU for a severe vaso-occlusive crisis complicated by acute chest syndrome, requiring intubation and assist-control ventilation. He is on a norepinephrine infusion for hypotension and has developed acute kidney injury: baseline creatinine was 0.8 mg/dL but has risen to 3.5 mg/dL over 24 hours with anuria, prompting initiation of continuous renal replacement therapy (CRRT). He takes chronic hydroxyurea at 25 mg/kg/day (~1750 mg/day) and has a history of reduced crisis frequency. His current labs show WBC 2.2 × 10^9/L, Hgb 7.5 g/dL, and platelets 150 × 10^9/L. Considering his AKI requiring CRRT and marked myelosuppression, which of the following is the most appropriate immediate adjustment to his hydroxyurea therapy?

A 32-year-old man with sickle cell anemia was admitted to the ICU two days ago for a severe vaso-occlusive pain crisis. His baseline hemoglobin is 8.5 g/dL. He is receiving bilevel positive airway pressure (BiPAP) with FiO2 0.40 for hypoxemia and a continuous hydromorphone infusion at 0.5 mg/hr via a central venous catheter for pain control. On evening rounds (hospital day 2), temperature is 38.9°C, BP 110/70 mmHg, HR 110 bpm, RR 24 breaths/min, SpO2 88% on BiPAP. He reports increased productive cough and worsening dyspnea. Chest X-ray shows new bilateral lower lobe infiltrates. WBC count is 18,000/mm³. Blood and sputum cultures have been drawn and are pending. Which of the following is the most appropriate initial pharmacologic intervention?

A 28-year-old man with sickle cell disease is admitted to the ICU for a severe vaso-occlusive crisis. He is on a continuous hydromorphone infusion at 2 mg/hr via a central line and 4 L/min nasal cannula oxygen. Overnight he develops a fever of 38.7 °C, a new productive cough with clear sputum, scattered crackles on lung exam, and his SpO₂ is 92% on 4 L NC. An arterial blood gas shows PaO₂ 62 mmHg. His hemoglobin is 7.2 g/dL (baseline 8.5), WBC 16,000/mm³, creatinine 1.0 mg/dL (baseline 0.8). Chest X-ray reveals a new right lower lobe infiltrate. Considering his presentation, which finding is the most critical indicator that he has developed Acute Chest Syndrome requiring immediate, advanced intervention?

A 30-year-old man with a history of sickle cell disease is admitted to the critical care unit following a severe vaso-occlusive crisis complicated by acute chest syndrome. He is intubated and on assist-control mechanical ventilation, receiving a continuous intravenous hydromorphone infusion for pain control and norepinephrine via a central line to maintain mean arterial pressure. After 7 days in the ICU with fluctuating levels of consciousness and frequent ventilator adjustments, his family is concerned about prolonged sedation and inability to communicate. Which of the following interventions is the priority for mitigating the risk of Post-Intensive Care Syndrome (PICS)?

A 19-year-old man with a history of sickle cell disease (SCD) presents to the emergency department with a 10/10 pain score in his back and legs, consistent with his usual vaso‐occlusive crises (VOC). On triage his vital signs are: temperature 37.0°C, heart rate 110/min, blood pressure 120/75 mm Hg, respiratory rate 18/min, SpO₂ 98% on room air. Physical exam shows tenderness over the lumbar spine and bilateral lower extremities without swelling or signs of infection and no respiratory distress. He has no known drug allergies and reports taking oral hydromorphone 2 mg every 4 hours as needed at home, with his last dose 8 hours ago. According to current evidence‐based guidelines for managing acute VOC pain in SCD, which of the following is the most appropriate initial intervention?

A 30-year-old man with sickle cell disease was admitted to the ICU for a severe vaso-occlusive crisis complicated by acute chest syndrome requiring mechanical ventilation and a continuous norepinephrine infusion. Over the past 72 hours, he has improved: he was extubated, vasopressors were discontinued, and his pain is well controlled on oral opioids. His current vital signs are stable. Laboratory studies show hemoglobin 7.8 g/dL (baseline 7.0–8.5), WBC 10.2×10^3/mm^3, and platelets 350×10^3/mm^3. He is tolerating oral intake and ambulating in his room. Which of the following is the MOST appropriate next step to determine readiness for transfer out of the ICU?

A 32-year-old man (70 kg) with sickle cell disease is admitted to the ICU for a severe vaso-occlusive crisis complicated by acute chest syndrome. He is mechanically ventilated, receiving a continuous opioid infusion, and has a central venous catheter in place. His vital signs are: HR 110 bpm, BP 95/60 mmHg, RR 18 breaths/min (ventilator-controlled), SpO₂ 92% on an FiO₂ of 0.6. Laboratory results: Hgb 7.2 g/dL (baseline 8.5), Cr 1.8 mg/dL (baseline 0.9), BUN 35 mg/dL. His urine output over the last 4 hours has been 0.3 mL/kg/hr despite a 500 mL normal saline bolus in the ED. His central venous pressure is 6 mmHg. Which of the following is the most appropriate initial IV fluid strategy?

A 28-year-old man with sickle cell disease was admitted for a severe vaso-occlusive crisis. He is now clinically stable on continuous intravenous hydromorphone via a patient-controlled analgesia (PCA) pump, with a reported pain score of 2/10. He is tolerating oral intake. Over the past 24 hours, he received a total of 12 mg of IV hydromorphone. Discharge is planned for tomorrow. Which of the following is the most appropriate plan for transitioning this patient’s pain management to an oral regimen?

A 28-year-old man with sickle cell disease is admitted to the ICU for a severe vaso-occlusive crisis. He has a central line and is on continuous monitoring, which shows a respiratory rate of 10 breaths/min and an SpO2 of 94% on 2 L nasal cannula. He is somnolent but arousable. Despite frequent demands on his hydromorphone PCA pump (0.5 mg demand dose, 10-minute lockout, 6 mg/4 h limit), he continues to report pain of 8/10. Given inadequate analgesia and signs of opioid-induced respiratory depression, which of the following is the most appropriate next intervention?

A 28-year-old man with sickle cell disease is admitted to the ICU on mechanical ventilation and a norepinephrine infusion for hypotension. He has severe, diffuse body pain refractory to high-dose opioids, fever to 38.9 °C, and worsening dyspnea. Arterial blood gas shows pH 7.28, PaCO₂ 48 mm Hg, PaO₂ 65 mm Hg on 80% FiO₂. Hemoglobin is 6.2 g/dL (baseline 8.5 g/dL). Chest X-ray reveals new bilateral pulmonary infiltrates. Which of the following is the most likely diagnosis?