Soru

A $49$-year-old man arrives at the emergency department due to a $24$-hour history of unremitting, severe abdominal pain. He reports multiple episodes of dark green vomiting and an inability to pass flatus since the onset of his symptoms. His surgical history is notable for a ruptured appendix requiring an open midline laparotomy at age $20$. His temperature is $38.5^\circ\text{C}$ ($101.3^\circ\text{F}$), blood pressure is $96/55\text{ mm Hg}$, pulse is $124/\text{min}$, and respirations are $22/\text{min}$. Physical examination reveals a visibly distended abdomen that is diffusely tender. There is pronounced involuntary guarding and board-like rigidity. Laboratory studies show a leukocyte count of $18,500/\text{mm}^3$ with $15\%$ bandemia and a serum lactate of $4.2\text{ mmol/L}$. An upright abdominal radiograph demonstrates multiple dilated loops of small bowel with air-fluid levels, and no free air under the diaphragm. Which of the following is the most appropriate next step in the management of this patient?