National surgical quality improvement program analysis of bariatric operations: Modifiable risk factors contribute to bariatric surgical adverse outcomes

BACKGROUND: The increase in obesity coupled with greater acceptance of the field of bariatric surgery has resulted in a substantial rise in the number of weight-loss operations. Because obese individuals are at high risk for surgical complications, concern about the safety of bariatric procedures exists. Earlier investigations of the clinical features associated with surgical complications have produced conflicting results. We sought to identify risk factors for surgical complications in a large, nationally representative population of US veterans. STUDY DESIGN: We analyzed data on bariatric procedures performed at 12 Veterans' Affairs medical centers approved to perform weight-loss operations between 1998 and 2004. Detailed pre-, intra, and postoperative information and longterm mortality data were prospectively collected using the National Surgical Quality Improvement Program methodology. We used multivariable logistic regression to identify clinical features associated with postoperative complications. RESULTS: Among 575 bariatric patients assessed between 1998 and 2004, 74% were men with a mean age of 51 years. Thirty-day mortality was 1.4%. Overall complication rate was 19.7%. Of those with complications, one-half were of considerable clinical importance, as they were associated with prolonged length of stay. Clinical features that were predictive of adverse events in our multivariable analyses were superobesity, weight > 350 pounds, and smoking. A more than 20 pack-year history of smoking was also associated with difficulty in weaning from a ventilator postoperatively. CONCLUSIONS: We identified smoking and superobesity as preoperative risk factors associated with postoperative complications. Future studies should examine the effect of preoperative weight loss and smoking cessation on bariatric procedure outcomes.