Question

A $42$-year-old woman presents to the emergency department with a $4$-hour history of sudden-onset, severe, colicky periumbilical pain that radiates to her back. She also reports several episodes of severe nausea and nonbilious emesis. Her medical history is notable for morbid obesity treated with a laparoscopic Roux-en-Y gastric bypass $3$ years ago. Her temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure is $135/85\text{ mm Hg}$, pulse is $112/\text{min}$, and respirations are $18/\text{min}$. On physical examination, her abdomen is soft and non-distended but exquisitely tender to deep palpation in the mid-abdomen. There is no rebound tenderness or muscle guarding. Bowel sounds are hyperactive. Laboratory studies show a leukocyte count of $9,500/\text{mm}^3$ and a serum lactate level of $1.2\text{ mmol/L}$ (normal: $0.5-2.2\text{ mmol/L}$). A computed tomography scan of the abdomen and pelvis with intravenous contrast reveals a cluster of dilated small bowel loops in the left upper quadrant and a swirling pattern of the mesenteric vessels at the root of the mesentery. Which of the following is the most appropriate next step in management?