New developments in gastric bypass procedures and physiological mechanisms.

Since the gastric bypass was first described for weight-reduction surgery almost 50 years ago, a number of remarkable contributions have been made to the field. These advances have led to significant modifications of the technique, evolution of laparoscopic bariatric surgery equipment, and improvement of long-term results. Despite the currently wide-spread practice of laparoscopic bariatric surgery, the precise technique for laparoscopic gastric bypass still varies from institution to institution, and the surgery continues to carry a morbidity rate. Advances in laparoscopic equipment, technology, and our understanding of the pathophysiology behind weight loss, have allowed surgeons to modify the procedure described originally to minimize the morbidity and maximize long-term weight loss. This chapter describes the technique of laparoscopic gastric bypass used at a major academic center that performs over 1000 bariatric procedures each year. In addition, the many recent advances in methodology and pathophysiology are described in detail.