Soru

A 68-year-old woman is evaluated in the emergency department for a 2-day history of progressive, crampy abdominal pain, nausea, and bilious vomiting. She has not passed flatus or stool for the past 24 hours. Her medical history is significant for a total abdominal hysterectomy performed 10 years ago for benign disease. Her temperature is 38.1°C (100.6°F), pulse is 112/min, blood pressure is 105/65 mm Hg, and respirations are 20/min. Physical examination reveals a markedly distended and tympanitic abdomen. Bowel sounds are high-pitched and tinkling. There is focal tenderness to deep palpation in the right lower quadrant with guarding, but no generalized rigidity is present. Laboratory studies show a leukocyte count of 16,500/mm³ (80% segmented neutrophils, 8% bands) and a serum lactate level of 2.8 mmol/L. A CT scan of the abdomen and pelvis with intravenous contrast demonstrates dilated loops of small bowel up to 4.5 cm in diameter with a discrete transition point in the distal ileum. The bowel wall at the transition point is mildly thickened and shows notably decreased contrast enhancement compared to adjacent small bowel loops. A small amount of free fluid is noted in the pelvis; there is no pneumoperitoneum. Which of the following is the most appropriate next step in management?