Perioperative Safety and Volume: Outcomes Relationships in Bariatric Surgery: A Study of 32,000 Patients

BACKGROUND: Accreditation of Centers of Excellence in bariatric surgery requires a hospital volume of more than 125 procedures/year. There is no evidence-based rationale for this specific threshold. Our objective was to evaluate the contemporary perioperative safety of bariatric surgery and to characterize the relationship between volume and outcomes. STUDY DESIGN: We queried the Nationwide Inpatient Sample 2005-2007 for open and laparoscopic bariatric procedures, complications, and death. RESULTS: Thirty-two thousand five hundred and nine bariatric procedures were identified (21% open bypass [Open], 58% laparoscopic bypass [Lap], 21% laparoscopic gastric band [Band]). Inpatient overall mortality was low (total 0.12%, Open 0.3%, Lap 0.09%, Band 0.02%; p < 0.05 for all comparisons). Inpatient complications were more prevalent (total 3.9%, Open 5.9%, Lap 4%, Band 1.6%, p < 0.01 for all comparisons). For all 3 procedures, using a combined end point of mortality and major complications, a volume-outcomes relationship was evident for hospitals. This relationship appeared linear with no clear point that maximally differentiated high-and low-volume centers. CONCLUSIONS: Using a nationwide dataset and bariatric procedure-specific data, we have demonstrated that bariatric surgery mortality and complication rates are very low. A definite volume-outcomes relationship exists when hospital-level data are analyzed, but there is no inflection point to justify selecting a specific volume threshold to determine Centers of Excellence. Low-volume centers with extremely low complication rates can be identified and, conversely, there are high-volume centers with elevated rates of complication. (J Am Coll Surg 2011;213:771-777. (C) 2011 by the American College of Surgeons)