An 81-year-old woman with chronic atrial fibrillation has had severe abdominal pain for the past 2 hours. Physical examination shows mild abdominal tenderness. Bowel sounds are absent. Fecal occult blood is positive. Leukocytes are 25,000/μL. Arterial blood gas shows:
pH 7.20
PCO2 34 mm Hg
PO2 85 mm Hg
An abdominal x-ray shows a non-specific gas pattern. Which of the following is the next best step in management?
Colonoscopy
CT scan of the abdomen with contrast
Exploratory celiotomy
IV lactated Ringer + observation
Laparoscopy
Paracentesis
