Perforation and surgical prognosis of acute appendicitis, and a prediction nomogram for perforated appendicitis in adults: a retrospective study

Abstract Background The safety and feasibility of performing appendectomy beyond the initial 72-hour period following symptom onset remain largely unknown. Aims This retrospective study aims to provide valuable insights for the prospective clinical management of acute appendicitis. Methods Case records of patients with acute appendicitis and those who underwent an appendectomy at our hospital between 2014 and 2020 were analyzed. Propensity score matching was employed to mitigate and control for selection bias in each case. To construct a prediction nomogram, 468 patients with acute appendicitis admitted between Jan 1, 2014 and Mar 31, 2019 were divided into a training cohort, while those admitted between Apr 1, 2019 and Dec 31, 2020, constituted the validation cohort. Results Patients with pre-hospital delays under 72 hours did not exhibit significant differences in surgery time, hospitalization, and postoperative complications compared to those with delays over 72 hours. However, there was a significant difference in the occurrence of appendiceal perforation. We then developed a prediction model to forecast the occurrence of appendiceal perforation. The reliability of the prediction nomogram was established through calibration curve analysis, decision curve analysis, and external validation. Conclusion Pre-hospital delay was an independent risk factor for appendiceal perforation, but not a factor directly affecting the prognosis of surgery. A nomogram based on perioperative factors was developed to predict the occurrence of appendiceal perforation in adults. This nomogram offers clinicians a precise and effective tool for early prediction of perforated appendicitis.