Bedside Sonography Performed by Emergency Physicians to Detect Appendicitis in Children

Abstract

Objective: The aim of this study was to evaluate the ability of emergency physicians with various levels of point-of-care ultrasound (POCUS) experience to detect appendicitis with POCUS among children visiting a pediatric emergency department (ED).

Methods: A prospective cohort study was conducted in an urban, tertiary care pediatric ED. Children aged 2 to 18 years old who presented with acute abdominal pain suggesting appendicitis were included. Patients were excluded if they had a history of appendectomy or hemodynamic instability requiring resuscitation or were transferred with proven diagnosis of appendicitis. Participating physicians had various levels of POCUS experience. Four of the 22 physicians were experienced in bowel sonography while the others had basic experience in abdominal POCUS. All the participating physicians received a 1-hour didactic and practical training session on appendix ultrasound. The treating physician performed POCUS following initial physical examination, before further radiologic evaluation. POCUS examinations were recorded as positive for appendicitis, normal, or inconclusive, with normal or inconclusive studies considered negative. Final outcomes were determined by pathology and/or operative reports for surgical cases and telephone follow-up at 3 weeks for those who did not have surgery. The primary analysis was a simple proportion for sensitivity and specificity for POCUS. Expecting a sensitivity of 80% based on previous studies, we calculated that a sample size of 50 cases would provide a 95% confidence interval (CI) ranging from 66% to 90%.

Results: Of the 140 approached patients, 121 accepted to participate and were recruited. After four patients were excluded for missing POCUS data, 117 patients were included in the primary analysis, of whom 51 (44%) had appendicitis. Twenty-two physicians performed between one and 20 POCUS procedures. The POCUS was positive in 39, negative in nine, and inconclusive in 69 patients. POCUS was interpreted as positive in 27 of 51 appendicitis for a sensitivity of 0.53 (95% CI = 0.40-0.66). A negative or inconclusive POCUS was reported for 54 of 66 patients without appendicitis (specificity = 0.82; 95% CI = 0.71-0.89).

Conclusion: This study shows limited sensitivity and specificity of POCUS for appendicitis in children, with a high proportion of inconclusive examinations, when performed by emergency physicians with various level of experience in POCUS.