A 71-year-old man is brought to the ED for a 12-hour history of severe abdominal pain. He has chronic atrial fibrillation and osteoarthritis. Vitals are: temp 99 F, HR 110, RR 16, BP 120/80. The abdomen is mildly distended. There is diffuse tenderness to palpation without rebound. Fecal occult blood is positive. Laboratory studies show:
Hb 14 g/dL
WBC 12,000/μL
pH 7.29
pCO2 24 mm Hg
Which of the following is the next best step in diagnosis?
Amylase and lipase
Endoscopic retrograde cholangiopancreatography (ERCP)
HIDA scan
Mesenteric angiography
Magnetic resonance cholangiopancreatography (MRCP)
