Meta-analysis of unplanned readmission to hospital post-appendectomy: an opportunity for a new benchmark

Background: Appendicitis is the most common cause of acute abdominal pain requiring surgical intervention. While many studies report readmission, a meta-analysis of readmission post-appendectomy has not been published. This meta-analysis was undertaken to determine rates and predictors of hospital readmission following appendectomy and to potentially provide a metric benchmark. Methods: An ethically approved PROSPERO-registered (ID CRD42017069040) meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using databases PubMed and Scopus, was undertaken for studies published between January 2012 and June 2017. Articles relating to outcomes and readmissions after appendectomy were identified. Those scoring >15 for comparative studies and >10 for non-comparative studies, using Methodological Index for Non-Randomized Studies criteria were included in the final analysis. The odds ratios (OR) using random-effects, Mantel–Haenszel method with 95% confidence intervals (CI), were computed for each risk factor with RevMan5. Results: A total of 1757 articles reviewed were reduced to 45 qualifying studies for a final analysis of 836 921 appendectomies. 4.3% (range 0.0–14.4%) of patients were readmitted within 30 days. Significant preoperative patient factors for increased readmission were diabetes mellitus (OR 1.93, CI 1.63–2.28, P < 0.00001), complicated appendicitis (OR 3.6, CI 2.43–5.34, P < 0.00001) and open surgical technique (OR 1.39, CI 1.08–1.79, P < 0.00001). Increased readmission was not associated with gender, obesity or paediatric versus general surgeons or centres. Conclusion: This meta-analysis identified that readmission is not uncommon post-appendectomy, occurring in one in 25 cases. The mean readmission rate of 4.3% may act as a quality benchmark for improving emergency surgical care. Targeting high-risk groups with diabetes or complicated appendicitis and increasing use of laparoscopic technique may help reduce readmission rates.