Background: Although proposed as a means for quality improvement, little is known regarding the economic consequences of volume-based referral. The objective of the current study was to investigate the relationship between inpatient costs and hospital volume.
Methods: Patients undergoing elective liver surgery were identified using the Nationwide Inpatient Sample from 2001 to 2012. Multivariable hierarchical regression analyses were performed to calculate and compare risk-adjusted costs and postoperative outcomes across hospital volume terciles.
Results: A total of 27,813 patients underwent surgery at 2207 hospitals. Although costs were comparable across the three volume groups (all p > 0.05), patients who developed a postoperative complication incurred a higher overall cost (complication vs. no complication; median costs $17,974 [IQR 13,865-25,623] vs. $41,731 [IQR 27,008-64,266], p < 0.001). In contrast, while the incidence of postoperative complications (low vs. intermediate vs. high; 22.0 vs. 19.2 vs. 13.0 %, p < 0.001) and subsequent failure-to-rescue (low vs. intermediate vs. high; 16.6 vs. 24.7 vs. 15.1 %, p < 0.001) was lower at high-volume hospitals, costs associated with "rescue" were substantially higher at high-volume hospitals (low vs. intermediate vs. high; $39,289 vs. $36,157 vs. $48,559, both p < 0.001).
Conclusions: Compared with lower volume hospitals, improved outcomes among patients who developed a complication at high-volume hospitals were associated with an increased cost.
Keywords: Complication; Costs; Hospital variation; Liver surgery.