One of the big questions patients have after completing the pre-operative requirements for weight loss surgery is whether they should proceed with a robotic Roux-en-Y Gastric Bypass (rRYGB) or Laparoscopic Sleeve Gastrectomy (LSG). Both operations offer better weight loss than diet and exercise alone, but there are several reasons to opt for one over the other.
Multiple studies have been done looking at type 2 diabetes resolution, and the majority have the conclusion that the rRYGB is better at long term remission than LSG. Type 2 diabetes remission is influenced by more severe disease. Factors contributing to severity of disease include the length of time a patient has had diabetes, the number of medications required to control their diabetes, whether insulin has had to be used as one of the medications, and higher average serum glucose level (as determined by hemoglobin A1C). With severe disease, LSG and rRYGB have similar remission rates and diabetes is less of a reason to choose one over the other. The Cleveland Clinic has developed a calculator to assist in procedure choice if diabetes control is the only factor a patient is interested in, and we use this calculator regularly in discussions with our patients who are trying to make this decision.
Another factor influencing the choice of procedure is gastro-esophageal reflux disease (GERD). As LSG turns the low pressure system of a normal stomach into a high pressure system, it can contribute to new onset or worsening of existing GERD. If a patient's primary concern is control of GERD, gastric bypass is the procedure of choice as it virtually eliminates GERD. If a patient has Barrett's esophagus related to their GERD, LSG is not a good procedure as reflux is worsened and the replacement for the esophagus should esophageal cancer develop is the portion of the stomach that is removed in LSG.
Most comparative studies show slightly higher excess body weight loss and more durability with rRYGB. LSG on the other hand is likely associated with fewer micronutrient and vitamin deficiencies and has had lower early post operative complications.
One of the major factors I mention to patients who ask this question is that from a surgical standpoint, it is relatively easy to convert an LSG into a rRYGB or a duodenal switch or loop duodenal switch. I don't recommend changing rRYGB into an LSG or duodenal switch.