No association between hospital volume and short-term outcomes of some common surgeries: a retrospective cohort study based on a Japanese nationwide database

Purpose: Centralization of high-risk surgeries has become a widespread strategy. However, whether or not the hospital volume affects the outcomes of common surgeries remains unclear. This study explored the association between hospital volume and short-term outcomes of common surgeries, as represented by appendectomy, cholecystectomy, and pneumothorax surgery, by analyzing data from a Japanese nationwide database. Methods: All hospitals were categorized into four groups (very low-, low-, high-, and very high-volume) according to the annual hospital volume of all gastrointestinal surgeries or all respiratory surgeries in 2017. Patient demographic data and surgical outcomes were evaluated across hospital volume categories. Results: We analyzed 2392 facilities which performed 771,182 gastrointestinal surgeries, and 992 facilities which performed 98,656 respiratory surgeries. Short-term outcomes of patients who underwent appendectomy (n = 50,568), cholecystectomy (n = 104,262), and pneumothorax surgery (n = 11,723) were evaluated. The incidences of postoperative complications, reoperation, and readmission were similar among the groups. Multivariable logistic regression analyses revealed hospital volume to have no association with these short-term outcomes. Conclusion: Analyses of a Japanese nationwide database revealed that the hospital volume was not associated with short-term outcomes of appendectomy, cholecystectomy, and pneumothorax surgery. These common surgical procedures may not require centralization into high-volume hospitals.