Effect of an Evaluation Algorithm on CT Utilization in Identifying Appendicitis in Children

Abstract

Objective: Our objective was to determine if there was a significant change in computed tomography (CT) utilization or length of stay (LOS) among patients evaluated for acute appendicitis after implementation of an appendicitis evaluation algorithm.

Methods: We conducted a retrospective chart review of patients aged 3-18 years in an urban, tertiary pediatric emergency department with acute abdominal pain, evaluated for appendicitis. Data were collected for 6 months preimplementation and postimplementation of the evaluation algorithm with a 3-month washout period between September 2018 and November 2019. Main outcomes were rate of CT utilization and LOS preimplementation and postimplementation and were analyzed using χ 2 test and Mann-Whitney U test, respectively. Descriptive analysis of demographics was performed, in addition to logistic regression to assess differences between the 2 study periods.

Results: A total of 2872 charts were identified with a chief complaint inclusive of "abdominal pain." Of these, 1510 met age requirements but did not meet at least 1 inclusion criteria; 229 more were excluded upon chart review for a final study sample of 1133 patients. Of these, 648 (57.2%) were female, 747 (65.9%) were White, and 988 (87.2%) were non-Hispanic. The majority of patients (770, 68%) were discharged home from the emergency department without a diagnosis of acute appendicitis. Neither CT (25.7% to 24.8%; P = 0.794) nor ultrasound (59.5% to 59.7%; P = 1.000) utilization significantly changed postimplementation. Total ED median LOS increased significantly (333.50 to 362.00 minutes; P = 0.011). Significant factors associated with CT utilization included fever, migration of pain, and right lower quadrant tenderness. Significant factors associated with appendicitis diagnosis included right lower quadrant pain, nausea/vomiting, migration of pain, and peritoneal signs.

Conclusions: Overall, the appendicitis evaluation algorithm did not significantly decrease CT utilization or LOS. Equivocal grade 2 or 3 ultrasound finding rates were high, likely leading to higher rates of CT utilization and increasing LOS.