A 45-year-old man is brought to the emergency department unresponsive after an apparent ethylene glycol (antifreeze) ingestion. He is intubated for airway protection (GCS 6) and is hypotensive (BP 80/45 mm Hg, HR 125 bpm) requiring vasopressors via a central line. Laboratory evaluation shows a severe high-anion-gap metabolic acidosis (pH 7.18, HCO₃⁻ 12 mEq/L) and acute kidney injury (creatinine 2.5 mg/dL from a baseline of 0.9 mg/dL). Which of the following is the most appropriate immediate management plan?

A 45-year-old man (70 kg) is brought to the emergency department approximately 4 hours after suspected antifreeze ingestion. On arrival, his blood pressure is 90/50 mm Hg, heart rate 110/min, respiratory rate 24/min, and temperature 36.8 °C. In the ICU, he is intubated for airway protection and requires norepinephrine for hypotension. Initial laboratory studies show arterial pH 7.18, HCO₃⁻ 12 mEq/L, an anion gap of 28, creatinine 2.5 mg/dL, and a serum ethylene glycol level pending. Which of the following interventions is the most critical next step in this patient’s management?

A 45-year-old, 70-kg man is admitted after acute ethylene glycol ingestion. He presents with altered mental status, a pH of 7.05, pCO₂ of 25 mm Hg, HCO₃⁻ of 8 mEq/L, and an anion gap of 28 mEq/L. His serum creatinine has risen from 0.9 to 2.5 mg/dL, and urine output is <0.5 mL/kg/hr for 6 hours. Fomepizole loading dose (15 mg/kg) was administered, and continuous renal replacement therapy (CRRT) has just been initiated. Which adjustment to his fomepizole regimen is MOST appropriate during CRRT?

A 45-year-old man is admitted to the ICU on assist-control ventilation and norepinephrine 0.1 mcg/kg/min via a right internal jugular central line. He was found unresponsive with an empty bottle of an unknown substance nearby. Initial labs show pH 7.18, pCO₂ 28 mmHg, HCO₃⁻ 10 mEq/L, anion gap 22 mEq/L, measured serum osmolality 320 mOsm/kg, calculated osmol gap 40 mOsm/kg. Blood ethanol is undetectable, and urine toxicology is negative. While awaiting definitive toxicant identification, which of the following initial management strategies is MOST appropriate?

A 35-year-old man is admitted to the ICU approximately 4 hours after a suspected ethylene glycol ingestion in a suicide attempt. He is intubated and receiving assist-control ventilation and a norepinephrine infusion at 0.1 mcg/kg/min via a central line to maintain a mean arterial pressure above 65 mmHg. Initial laboratory studies show a pH of 6.98, bicarbonate 8 mEq/L, an anion gap of 28 mEq/L, and an osmolal gap of 35 mOsm/kg. Which of the following is the most critical initial management intervention?

A 70-kg, 45-year-old man is admitted to the ICU with a Glasgow Coma Scale score of 3 and requires mechanical ventilation for severe respiratory depression. He is receiving norepinephrine at 0.2 mcg/kg/min via a central line to maintain a mean arterial pressure ≥65 mmHg. His pupils are pinpoint and unresponsive to light, and arterial blood gas shows a pH of 7.05 with low bicarbonate, indicating profound metabolic acidosis. The etiology is unknown, and no family is available. Which of the following interventions should be prioritized?

A 45-year-old, 70-kg man with hypertension (on lisinopril) underwent epidural anesthesia for abdominal surgery and is now in the ICU intubated on assist-control ventilation. He requires norepinephrine 0.3 µg/kg/min and vasopressin 0.04 units/min via a central venous catheter to maintain a MAP > 65 mmHg. His arterial blood gas is pH 7.25, PaCO₂ 40 mmHg, HCO₃⁻ 18 mmol/L; electrolytes: Na⁺ 138 mmol/L, K⁺ 4.1 mmol/L; lactate 8 mmol/L. Thirty minutes ago he developed generalized tonic-clonic seizures followed by wide-complex tachycardia that rapidly degenerated into PEA requiring CPR. Despite a 20% lipid emulsion bolus and infusion, benzodiazepines, and sodium bicarbonate, he remains in refractory cardiogenic shock. ECG now shows a QRS duration of 180 ms and HR 35 bpm. Which of the following is the most appropriate next step?

A 45-year-old man (weight 80 kg, height 1.80 m, BMI 24.7 kg/m2) with hypertension is admitted to the ICU 6 hours after ingesting an estimated 5 g of amitriptyline (≈60 mg/kg). He was found unresponsive at home with empty prescription bottles. On arrival, he required endotracheal intubation for a GCS of 3 and is receiving mechanical ventilation. A central venous catheter delivers norepinephrine. Despite 30 mL/kg crystalloid bolus, his MAP remains <65 mmHg, necessitating escalating norepinephrine (currently 0.3 μg/kg/min and rising). Arterial blood gas shows pH 7.18, pCO2 30 mmHg, HCO3– 10 mEq/L; serum lactate is 8.2 mmol/L. ECG reveals a QTc of 520 ms. Which finding most directly necessitates ICU-level care with advanced hemodynamic support?

A 45-year-old man is admitted to the intensive care unit after being found unresponsive. He is intubated on assist-control ventilation and has a central venous catheter in place. Despite initial fluid resuscitation, his mean arterial pressure remains below 65 mmHg, requiring an increasing norepinephrine infusion now at 0.2 mcg/kg/min. Initial laboratory studies reveal a pH of 7.15, bicarbonate of 11 mEq/L, and an anion gap of 29. An empty bottle of antifreeze was found at the scene. His ECG shows sinus tachycardia with a QTc of 520 ms. Given this patient’s refractory shock, which of the following is the most appropriate next step in management?

A 45-year-old man is admitted to the intensive care unit after being found unresponsive next to an empty antifreeze bottle. He is mechanically ventilated (FiO₂ 0.8, PEEP 10 cmH₂O) for severe ARDS and remains in refractory shock despite aggressive fluids and norepinephrine at 0.5 mcg/kg/min to maintain MAP 60–65 mmHg. Arterial blood gas shows pH 6.95, PaCO₂ 30 mmHg, HCO₃⁻ 5 mEq/L with an anion gap of 30. Lactate is 8 mmol/L and cardiac index is 1.8 L/min/m². Which of the following is the most appropriate next step in management?