Background: The American Association for the Surgery of Trauma (AAST) has proposed a grading system for anatomic severity of 16 Emergency General Surgery conditions, including appendicitis. This is the first prospective, multicenter clinical study evaluating the AAST Appendicitis grading scale.
Methods: The EAST Appendicitis study utilized data collected prospectively from 27 centers, between January 2017 to June 2018. An overall grade was assigned as the highest grade of the subscales: clinical, radiographic, operative, and pathologic. Grade 1-3 of the clinical subscale was assigned as Grade 1. Patients with a final diagnosis other than appendicitis were excluded. The cohort was divided into two groups: simple appendicitis (Grades 1 and 2), and complicated appendicitis (Grades 3, 4, and 5).Fisher's exact and Kruskal-Wallis tests were used to determine association between the overall AAST grade and the following outcomes: infectious complications, Clavien-Dindo complications, hospital length of stay (LOS), 30-day emergency department visits, readmissions, and secondary interventions.
Results: A total of 2,909 cases were analyzed: 1,656 (57%) were Grade 1; 181 (6%), Grade 2; 399 (14%) Grade 4; and 549 (19%) Grade 5; 94% of patients underwent appendectomy. Index hospitalization LOS increased significantly with increasing grade: 1, [1,1], 1 [1,2], 1 [1,2], 2 [1,3], and 32,5 (p < 0.001). Infectious complications, Clavien-Dindo complications, hospital LOS, and secondary interventions were significantly associated with increasing AAST severity grade during index hospitalization. For 30-day outcomes, similar trends were noted for readmission, 30-day infections complications, 30-day cumulative infectious complications, 30-day Clavien-Dindo complications, 30-day cumulative Clavien-Dindo complications, 30-day secondary interventions, and 30-day cumulative secondary interventions.
Conclusion: The AAST emergency general surgery grade for appendicitis is a valid predictor of clinical outcomes such as infectious complications, overall complications, and the need for secondary intervention.
Level of evidence: Prognostic, level III.