Cost-Effectiveness in Hepatic Lobectomy: the Effect of Case Volume on Mortality, Readmission, and Cost of Care

Abstract

Objective(s)Higher-volume centers demonstrate better perioperative outcomes for complex surgical interventions, though resource utilization implications of this hospital-level variation are unclear. We hypothesized that for hepatic lobectomy, higher operative volume correlates with better outcomes and lower costs. MethodsFrom 2009 to 2011, 4163 patients undergoing hepatic lobectomy were identified from the University HealthSystems Consortium database. Univariate, multivariate logistic regression, and decision analytic models were constructed to identify differences in hospital utilization and cost. Cost included both index and readmission hospitalizations, when applicable. ResultsThe annual number of hepatic lobectomies performed by the institutions within the study ranged from 1 to 86. The median age of the 4163 patients was 58 years with a roughly equal gender split (M/F 49 %:51 %) and a racial breakdown which reflected that of the general US population. For all patients, the overall perioperative mortality rate was 2.3 % and the 30-day readmission rate was 13.4 %. Hospitals performing >30 hepatic lobectomies per year had significantly lower mortality and readmission rates than those hospitals performing ≤15 lobectomies annually (both p < 0.05). On multivariate analysis, higher severity of illness (odd ratio (OR) 2.13, 95 % confidence interval (CI) [1.48–3.07], p < 0.001), discharge to rehab (OR 1.84, [1.28–2.64], p < 0.001), home with home health care (OR 1.38, [1.08–1.76], p = 0.01), and surgery at a low-volume hospital (OR 1.49, [1.18–1.88], p < 0.001) were significant predictors of readmission. Conversely, surgical intervention at high-volume centers was associated with decreased risk of readmission (OR 0.67, [0.53–0.85], p < 0.001). When both index and readmission costs were considered, per-patient cost at low-volume centers was 21.9 % higher than at high-volume centers ($19,669 vs. $16,137). Sensitivity analyses adjusting for perioperative mortality and readmission at all centers did not significantly change the analysis. ConclusionsThese data, for the first time, demonstrate that hospital volume in hepatic lobectomy is an important, modifiable risk factor for readmission and cost. To optimize resource utilization, patients undergoing complex hepatic surgery should be directed to higher-volume surgical institutions.