Background: This study explores the volume-outcome relationship for gastric bypass surgery for obesity to determine whether higher-volume hospitals, higher-volume surgeons, or both are associated fewer adverse outcomes.
Methods: The Pennsylvania state discharge database was used to identify 4685 cases of gastric bypass surgery for obesity between 1999 and 2001. Statistical modeling analyses were used to determine whether mortality or adverse outcome rate was significantly related to hospital and surgeon volume; the data were controlled for risk factors such as age, gender, comorbidities, and others.
Results: There were 28 deaths (0.6%) and 813 adverse outcomes (17.4%). There was a significant risk-adjusted relationship between surgeon volume and adverse outcome, and the same trend was observed for deaths. Surgeons who performed fewer than 10 procedures per year had a 28% risk of adverse outcome and a 5% risk of death, compared with 14% (P<.05) and 0.3% (P=.06), respectively, for high-volume surgeons. Hospital volume did not reach significance, but there was a striking interaction between surgeon and hospital volume; surgeons who performed 10 to 50 cases per year operating in low-volume hospitals had a 55% risk of adverse outcome (P<.01).
Conclusion: Risk-adjusted in-hospital adverse outcome is significantly lower when gastric bypass is performed by higher-volume surgeons.