Evaluating Trends in the Volume-Outcomes Relationship Following Liver Surgery: Does Regionalization Benefit All Patients the Same?

Introduction: Data evaluating trends in hospital volume are lacking. The current study sought to examine trends in outcomes relative to hospital volume following liver surgery. Methods: A total of 14,296 patients >18 years undergoing an elective liver resection (LR) for cancer were identified using the National Inpatient Sample from 2001 to 2011. Multivariable logistic regression analysis was performed to compare postoperative morbidity and mortality relative to hospital volume over time. Results: Over time, the proportion of patients undergoing a LR at a high-volume hospital (HVH) increased from 24.4 to 45.0 %, while the proportion of patients undergoing a LR at a low-volume hospital (LVH) decreased from 40.4 to 22.7 %. On multivariable analysis, patients undergoing a LR at high-volume hospitals demonstrated a 29 % lower odds of mortality (OR = 0.71, 95 % CI = 0.59–0.86, p < 0.001) compared with patients undergoing a LR at a LVH. The rate of regionalization, however, was not equal among all patients as older patients, patients belonging to a racial minority, and those presenting with substantial comorbidity were less likely to undergo a LR at a HVH. Conclusion: An increase in the regionalization of liver surgery was observed over time. Trends in regionalization were, however, associated with discrepancies in access to HVH among specific patient populations.