History of present illness: A 62-year-old woman presents to the emergency department in the early afternoon for 3 days of abdominal bloating and occasional vomiting that morphed into severe generalized abdominal pain starting 2 hours ago with more frequent vomiting. She had a bowel movement (BM) this morning that was normal. She denies any fever, diarrhea, bleeding or other complaints.
Vital signs & physical examination: She is moaning in pain. Vital signs are normal, but her blood pressure (BP) is in the 110s systolic, which seems low for the amount of discomfort she is in. Physical exam is otherwise normal except for diffused abdominal tenderness with guarding but without rebound.
Initial diagnostic testing: