Preoperative scoring system for prediction of extended resection during emergency surgery for acute appendicitis

Purpose Appendicectomy is the primary treatment for acute appendicitis. However, extended resection (ER) may be required in difficult cases. Preoperative prediction of ER may identify challenging cases but remains difficult. We aimed to establish a preoperative scoring system for ER prediction during emergency surgery for acute appendicitis. Methods This was a single-center retrospective study. Patients who underwent emergency surgery for acute appendicitis between January 2014 and December 2022 were included and divided into ER and appendicectomy groups. Independent variables associated with ER were identified using multivariate logistic regression analysis. A new scoring system was established based on these independent variables. The discrimination of the new scoring system was assessed using the area under the receiver operating characteristic curve (AUC). The risk categorization of the scoring system was also analyzed. Results Of the 179 patients in this study, 12 (6.7%) underwent ER. The time interval from symptom onset to surgery ≥ 4 days, a retrocecal or retrocolic appendix, and the presence of an abscess were identified as independent preoperative predictive factors for ER. The new scoring system was established based on these three variables, and the scores ranged from 0 to 6. The AUC of the scoring system was 0.877, and the rates of ER among patients in the low- (score, 0–2), medium- (score, 4), and high- (score, 6) risk groups were estimated to be 2.5%, 28.6%, and 80%, respectively. Conclusion Our scoring system may help surgeons identify patients with acute appendicitis requiring ER and facilitate decision-making regarding treatment options.