Question

A 48-year-old woman is evaluated in the intensive care unit for progressive confusion, right upper quadrant abdominal pain, and high fever over the past 24 hours. Her medical history is significant for a Roux-en-Y gastric bypass performed 3 years ago for severe obesity, and an uncomplicated laparoscopic cholecystectomy 10 years ago. She has no known allergies. Her temperature is $39.4^\circ\text{C}$ ($102.9^\circ\text{F}$), blood pressure is $82/50 \text{ mm Hg}$ despite the rapid administration of 3 L of intravenous crystalloid solution, heart rate is 128/min, and respiratory rate is 24/min. She has been started on a norepinephrine infusion. Physical examination reveals scleral icterus and marked tenderness in the right upper quadrant without rebound or guarding. She is lethargic and oriented only to person. Laboratory studies show:

- Leukocyte count: $22,000/\text{mm}^3$ (85% neutrophils, 10% bands)
- Platelet count: $95,000/\text{mm}^3$
- Total bilirubin: $8.4 \text{ mg/dL}$
- Direct bilirubin: $6.2 \text{ mg/dL}$
- Alkaline phosphatase: $520 \text{ U/L}$
- Aspartate aminotransferase (AST): $145 \text{ U/L}$
- Alanine aminotransferase (ALT): $130 \text{ U/L}$
- International normalized ratio (INR): $1.6$

A right upper quadrant ultrasound reveals a dilated common bile duct measuring 14 mm with internal echogenic debris and a suspected calculus in the distal aspect. The patient is receiving empiric intravenous broad-spectrum antibiotics. Which of the following is the most appropriate next step in the procedural management of this patient?