Colorectal cancer Quiz: Ace Your Exams

A 58-year-old man was brought to the emergency department with sudden onset severe abdominal pain and vomiting that began 6 hours ago. He reports intermittent crampy abdominal pain and bloating over the past week. However, since the early morning, the pain has been severe and sharp in nature and associated with nausea. He has been receiving chemotherapy for a known diagnosis of colorectal cancer. Additional past medical history is significant for hypertension, controlled with lisinopril. Temperature is 37.2°C (99°F), blood pressure is 85/50 mmHg, pulse is 110/min, respiratory rate is 22/min, and oxygen saturation is 97% on room air. Physical examination reveals absent bowel sounds and generalized abdominal tenderness, distension, and involuntary guarding over the lower abdomen. IV fluids are initiated. An upright chest x-ray is shown below. Which of the following is the best next step in management?
 
 ^{Reproduced from: Openi}