SAN DIEGO – Laparoscopic sleeve gastrectomy is safe and effective in obese candidates for organ transplantation, results from a novel pilot study demonstrated.
Nationwide, 15%-20% of patients on the transplant waiting list are morbidly obese, with a body mass index of greater than 35 kg/m2, "but many cannot be transplanted unless they lose weight," said Dr. Matthew Y. Lin of the surgery department at the University of California, San Francisco (UCSF). "Morbid obesity can contribute to end-stage kidney or liver failure. For example, obesity-related nonalcoholic steatohepatitis is now the third most common indication for liver transplant in the United States and will likely become first in the future."
Dr. Matthew Y. Lin
In what Dr. Lin said is the only reported case series of bariatric surgery in obese transplant candidates, he and his associates conducted a pilot study of 26 morbidly obese patients with liver or kidney failure who underwent laparoscopic sleeve gastrectomy at UCSF from 2006 to 2012. They chose sleeve gastrectomy over gastric banding "to avoid foreign body implantation, in anticipation of post-transplant immunosuppression," Dr. Lin explained at the annual meeting of the American Society for Metabolic and Bariatric Surgery.
"We chose sleeve gastrectomy over gastric bypass to maintain endoscopic access to the biliary system, to reduce surgical complexity, and to avoid unpredictable immunosuppression absorption," he said.
Morbid obesity is a relative contraindication for solid organ transplantation at most centers because of poor post-transplant outcomes, according to Dr. Lin. "At UCSF, the selection criteria are a BMI of less than 40 for liver transplant, less than 38 for kidney transplant, and less than 34 for kidney transplant in patients with diabetes." The researchers hypothesized that laparoscopic sleeve gastrectomy could be safely performed in high-risk patients with liver or kidney failure and achieve enough weight loss to allow for transplantation.
The 26 patients had a mean age of 57 years, 17 were women, 20 were white, and their average preoperative BMI was 48. Twenty patients had liver insufficiency with a mean Model for End-Stage Liver Disease (MELD) score of 11, and 6 had kidney insufficiency with a mean glomerular filtration rate of 10 mL/min. Five of these patients were on hemodialysis.
All 26 patients had laparoscopic sleeve gastrectomy performed by the same surgeon. The mean operative time was 151 minutes, and the mean length of stay was 4.2 days. Complications that occurred within 30 days were two cases of superficial wound infection and one case each of worsened hepatic encephalopathy, acute renal insufficiency, need for blood transfusion, and staple line leak. There was no mortality within 30 days, but after that period two patients died awaiting transplant and one patient died from complications of the staple line leak and progressive liver failure 4 years after surgery.
After 2 years, the average BMI of study participants dropped from a mean of 48 to a mean of 29. "Between the 6- and 12-month marks, most patients were able to achieve a BMI that would make them acceptable for transplant," Dr. Lin said.
At 1, 3, 12, and 24 months, the percent of excess body weight lost was 17%, 26%, 50%, and 66%, respectively. "The weight-loss profile is similar to [those of] the general bariatric sleeve gastrectomy population," he noted.
Of the 13 patients who had diabetes preoperatively, 7 had complete resolution after the procedure and 1 had partial resolution. Mean postoperative albumin levels for all 26 patients after sleeve gastrectomy were 3.1 g/dL at 6 months and 3.3 g/dL at 12 months.
Eight patients went on to receive their organ transplant, Dr. Lin said. Their mean age was 56 years, and six were women. They waited a mean of 17 months for their procedures, which included six liver transplants, one liver and kidney transplant, and one kidney transplant. Their mean BMI before sleeve gastrectomy was 46, and their mean BMI prior to transplantation was 31. Immediately before transplant, their mean albumin level was 3.2 g/dL, and the most current measurement remained the same. "No increased acute rejection or difficulty maintaining immunosuppression was observed," he said.
Dr. Lin acknowledged certain limitations of the study, including its single-center design, lack of a control population, and the fact that "there is very little statistical power to estimate the true complication rate in this high-risk surgical group. Furthermore, we only have short-term follow-up."
Dr. Lin said that he had no relevant financial conflicts to disclose.