Preoperative in-hospital delay increases postoperative morbidity and mortality in patients with acute appendicitis: a meta-analysis

Background: Complicated appendicitis is associated with high morbidity, mortality, and healthcare costs. However, the relationship of preoperative in-hospital delay >24 h with complicated appendicitis and postoperative morbidity remains unclear. This meta-analysis investigated the effects of preoperative in-hospital delay on complicated appendicitis and postoperative morbidity in patients with acute appendicitis. Materials and methods: This study adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 and A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR2) guidelines. The PubMed, Embase, Cochrane Library, and Web of Science databases up to October 14, 2023 (updated on March 16, 2024) were searched for randomized controlled trials and observational studies that evaluated the effect of preoperative in-hospital delays of >24 h on acute appendicitis. Odds ratios (OR) and 95% confidence intervals (CIs) were also determined. Results: We yielded 18 130 records, of which 28 studies (512 881 patients) were included in the meta-analysis. The risk of bias was considered serious, moderate, and low for 24, 3, and 1 study, respectively. Although preoperative in-hospital delays of >24 h were not associated with a higher risk of surgical-site infection (OR: 1.04, 95% CI: 0.97, 1.12, P=0.25), in-hospital delays of >24 h were a risk factor for complicated appendicitis (OR: 1.60, 95% CI: 1.25, 2.05, P=0.0002), and postoperative complications (OR: 1.51, 95% CI: 1.30, 1.75, P<0.00001). In addition, an in-hospital delay of >24 h before surgery increased the OR of postoperative mortality (OR: 1.81, 95% CI: 1.33, 2.45, P=0.0001). The sensitivity analyses also confirmed the robustness of our results. Conclusions: An in-hospital delay of >24 h is a risk factor for complicated appendicitis, postoperative complications, and mortality. Given the subsequent adverse outcomes of in-hospital delays, appendectomy should not be delayed for >24 h.