Impact of hospital volume and facility characteristics on postoperative outcomes after hepatectomy: A mediation analysis

The impact of hospital procedural volume on outcomes after hepatectomy relative to other facility-related factors remains unclear. We sought to define the comparative impact of hospital volume compared with other facility-related factors on postoperative outcomes among Medicare beneficiaries undergoing hepatectomy. Data on patients who underwent hepatectomy between 2013 and 2021 were collected from the Medicare Standard Analytic Files and linked with facility-level data from the American Hospital Association Survey databases. Hospital volume was stratified into high- (top 10%) and low-volume centers. Propensity score matching was used to account for variable imbalances in patient characteristics among high-compared with low-volume centers. Mediation analysis was employed to delineate facility-related factors responsible for the impact of hospital volume on outcomes with a specific focus on incidence of complications, in-hospital mortality, and failure to rescue. The analytic cohort included 22,969 patients from 340 institutions. After propensity score matching, receipt of surgery at a high-volume center was associated with a lower likelihood of postoperative complications (39.9% vs 41.7%, P = .01), in-hospital mortality (2.2% vs 2.8%, P = .02), and failure to rescue (5.4% vs 6.5%, P = .04) versus low-volume centers. Mediation analysis revealed that hospital capacity (bed capacity and nurse-to-bed ratio) contributed the most to the variations in risk of complications and in-hospital mortality, whereas liver transplant program status had the largest impact on failure to rescue. Hospital volume is a significant determinant of postoperative outcomes after hepatectomy, with hospital capacity and liver transplant program status being important mediators of this effect. Centralization and optimal resource distribution are important to achieve favorable outcomes following liver resection.