519 - Association of Higher Body Mass Index with Imaging Escalation and Operative Complexity in Pediatric Appendicitis

Publication Number: 2504.519

Ryan T. Davis, Corewell Health William Beaumont University Hospital, Troy, MI, United States; Sahithi Pemmasani, Corewell Health William Beaumont University Hospital, Royal Oak, MI, United States; Margaret Menoch, Corewell Health East William Beaumont University Hospital, Royal Oak, MI, United States

Background: Obesity may complicate clinical assessment and ultrasound (US) evaluation in children with appendicitis, potentially increasing reliance on computed tomography (CT). At the same time, national pediatric quality-improvement initiatives and ALARA-driven imaging pathways emphasize reducing CT use and promoting US-first approaches. Data examining how body mass index (BMI) influences diagnostic pathways within these modern low-radiation protocols are limited.

Objective: To determine whether higher BMI is associated with greater CT utilization, escalation from US to CT, nondiagnostic US examinations, emergency department (ED) length of stay (ED-LOS), and operative duration in children with appendicitis.

Design/Methods: This retrospective cohort study included patients < 18 years with surgically confirmed appendicitis presenting to a tertiary pediatric ED from January 1, 2010, to December 31, 2023. Consistent with prior dataset methodology, encounters were identified through structured EHR query using ICD-10 and CPT codes and restricted to unique first visits. A total of 2,275 children were included; BMI was available for 2,012 (88%). BMI was analyzed in quartiles. Imaging modality (US-only, CT-only, or CT after US) and operative duration (proxy for case complexity) were evaluated. χ² and Wilcoxon tests and odds ratios (OR) with 95% CI were used. IRB approval was obtained (Corewell Health IRB No. 2024-128).

Results: Children in the highest BMI quartile had higher CT utilization than those in the lowest quartile (35.6% vs 24.7%; OR 1.69, 95% CI 1.29-2.22) and more frequent escalation from US to CT (43.3% vs 25.8%; OR 2.20, 95% CI 1.39-3.48). Nondiagnostic US exams were more common with higher BMI (7.4% vs 4.2%). Operative duration was longer in the highest BMI group (median 49.0 vs 40.5 minutes; p< 0.05). ED-LOS was similar (5.68 vs 5.50 hours; p=0.77). Negative appendectomy rates did not differ.

Conclusion(s): Higher BMI in pediatric appendicitis is associated with increased CT use, greater escalation after US, higher nondiagnostic US rates, and longer operative duration. As national QI initiatives emphasize ultrasound-first algorithms and CT reduction, these findings highlight the need for BMI-informed imaging strategies and early surgical involvement to support equitable, efficient, and radiation-sparing care.

Imaging Pathway and Operative Duration by BMI Quartile
Body mass index (BMI) was analyzed in quartiles. Higher BMI was associated with increased computed tomography (CT) utilization, greater escalation from ultrasound (US) to CT, higher nondiagnostic US rates, and longer operative duration among children with appendicitis. Operative time used as a proxy for case complexity.