Abstract
Computed tomography (CT) and ultrasound (US) are used in emergency departments (ED) to aid in the diagnosis of patients with abdominal pain. To describe trends in CT and US use in United States EDs and determine if higher test use is associated with higher detection rates for intra-abdominal illnesses commonly detected on CT and US and lower hospital admission rates. Retrospective study using the 2001 to 2005 National Hospital Ambulatory Medical Care Survey, a nationally representative sample of ED encounters. ED patients presenting with abdominal pain. Annual rates of and trends in CT and US use, rates of intra-abdominal illnesses, hospital admission rate. Abdominal pain visits accounted for 38.8 million encounters; 17.8% received a CT and 11.7% received an US. CT use increased from 10.1% in 2001 to 22.5% in 2005 (P < 0.001). US use increased from 11.1% in 2001 to 13.6% in 2005 (P = 0.002). During the same period, detection rates for appendicitis, diverticulitis, and gall bladder disease did not increase and admission rates did not decrease. Despite a more than doubling in CT use and increases in US use, there was no increase in detection rates for appendicitis, diverticulitis, and gall bladder disease nor was there a reduction in admissions.