The Effects of Acute Preoperative Weight Loss on Laparoscopic Roux-en-Y Gastric Bypass

Background: Minimal acute pre-operative weight loss significantly reduces liver size and intra-abdominal adipose tissue. We hypothesize that these changes will reduce intra-operative complications and reduce the difficulty of laparoscopic Roux-en-Y gastric bypass (LRYGBP). Methods: This is a retrospective chart review of consecutive patients who had undergone isolated LRYGBP between July 2003 and March 2005. All patients participated in our institution's medically supervised Weight Management Program before surgery. Results: 48 patients (Weight Loss Group) had an average percent loss of excess weight (%EWL) of 4.6; whereas 47 patients (No Weight Loss Group) gained an average of 4.8% of excess weight over an average period of 2.4 and 3 months (P=0.09), respectively. There were no differences between the two groups in age, gender, ASA class, co-morbidities, or BMI at operation. The Weight Loss Group had less intra-operative blood loss (102 vs 72 ml, P=.03). The surgeon was also less likely to report an enlarged liver in the Weight Loss Group (P=.02). Finally, the operation was less likely to deviate from the standard LRYGBP when patients lost weight (P=.02). No differences were seen in operative time, length of hospital stay, wound infections, or major complications. Conclusion: Acute preoperative weight loss is associated with less intra-operative blood loss and reduces the need for intraoperative deviation from the standard LRYGBP. A larger series with a greater reduction in excess weight is necessary to determine the maximal benefits of acute preoperative weight loss.