The role of emergency department computed tomography in early acute pancreatitis.

INTRODUCTION: Computed tomography (CT) is often ordered for patients in whom the diagnosis of acute pancreatitis (AP) has already been established via elevated lipase levels and typical abdominal pain. We investigated whether early CT imaging performed in the ED altered the diagnosis or management.

METHODS: A retrospective chart review was performed on patients presenting to a large, academic ED between the years 2013-2015 with AP who received CT imaging. Relevant history, laboratory, imaging data, and hospital course were abstracted from the medical record and analyzed by three independent reviewers, with 100% agreement among reviewers on 30 randomly selected cases. The primary outcome was whether the CT led to a change in diagnosis or management above and beyond the ultrasound. Univariate and multivariate analyses were performed to determine association between predictor variables and outcomes.

RESULTS: The electronic health record query yielded 458 patients. Of those, 174 met the American College of Gastroenterology criteria for AP and were included in the study. 145 patients (83%) had abdominal CT during their hospital course, 125 (86%) of which were performed in the ED. Of these 145 patients, 57 (39%) had imaging evidence of AP. 107 patients had abdominal ultrasound (US) during their hospital course. Of 84 patients who had both CT and US, 31 (37%) patients were diagnosed with gallstones by US versus 19 (23%) by CT. Biliary dilation/obstruction was diagnosed by US in 5 (6%) patients versus 4 (5%) by CT. CT led to the correct diagnosis or change in management in 21 (14.5%) patients.

CONCLUSION: Early CT may alter the diagnosis or management in up to 15% of patients presenting to the ED with AP, especially older patients with prior episodes of pancreatitis and biliary interventions, however abdominal US may be a more sensitive screening study for biliary etiologies and thereby better direct further management.