Effect of Reduction in the Use of Computed Tomography on Clinical Outcomes of Appendicitis.

IMPORTANCE: Advanced diagnostic imaging is commonly used in the evaluation of suspected appendicitis in children. Despite its inferior diagnostic performance, ultrasonography (US) is now preferred to computed tomography (CT) owing to concerns about ionizing radiation exposure. With changes in imaging modalities, the influence on outcomes should be assessed.

OBJECTIVES: To review trends in the use of US and CT for children with appendicitis and to investigate simultaneous changes in the proportions of negative appendectomy, appendiceal perforation, and emergency department (ED) revisits.

DESIGN, SETTING, AND PARTICIPANTS: We reviewed the Pediatric Health Information System administrative database for children who presented to the ED with the diagnosis of appendicitis or who underwent an appendectomy in 35 US pediatric institutions from January 1, 2010, through December 31, 2013.

MAIN OUTCOMES AND MEASURES: We studied the use of US and CT for trends and their association with negative appendectomy, appendiceal perforation, and 3-day ED revisits.

RESULTS: Our investigation included 52,153 children with appendicitis. Use of US increased 46% (from 24.0% in 2010 to 35.3% in 2013; absolute difference, 11.3%; adjusted test for linear trend, P = .02), whereas use of CT decreased 48% (from 21.4% in 2010 to 11.6% in 2013; absolute difference, -9.8%; adjusted test for linear trend, P < .001). The proportion of negative appendectomy declined during the 4-year study period from 4.7% in 2010 to 3.6% in 2013 (test for linear trend, P = .002), whereas the proportion of perforations (32.3% in 2010 to 31.9% in 2013) and ED revisits (5.6% in 2010 and 2013) did not change (adjusted tests for linear trend, P = .64 and P = .84, respectively).

CONCLUSIONS AND RELEVANCE: Among children with suspected appendicitis, the use of US imaging has increased substantially as the use of CT has declined. Despite the increased reliance on the diagnostically inferior US, important condition-specific quality measures, including the frequency of appendiceal perforation and ED revisits, remained stable, and the proportion of negative appendectomy declined slightly.