Question

A 28-year-old woman is brought to the emergency department due to a 2-day history of worsening, diffuse abdominal pain and recurrent vomiting of greenish material. She reports that her pain was initially crampy and intermittent but has become constant and severe over the past 6 hours. She has not had a bowel movement or passed flatus since the symptoms began. Her medical history is significant for stricturing ileal Crohn's disease, for which she was previously treated with infliximab, but she discontinued all medications a year ago. Her temperature is $38.8^\circ\text{C}$ ($101.8^\circ\text{F}$), pulse is $124/\text{min}$, blood pressure is $88/54 \text{ mmHg}$, and respirations are $22/\text{min}$. Physical examination reveals a distended, tympanitic abdomen with absent bowel sounds. There is diffuse tenderness with marked guarding and rebound tenderness in the right lower quadrant. Laboratory studies show a leukocyte count of $21,000/\text{mm}^3$ with $15\%$ bands, and a serum lactate level of $4.8 \text{ mmol/L}$. An abdominal CT scan with intravenous contrast demonstrates markedly dilated loops of small intestine with a distinct transition point in the terminal ileum. There is circumferential thickening of the terminal ileum, pneumatosis intestinalis, and moderate free fluid in the pelvis. Which of the following is the most appropriate next step in management?