A recent paper, ‘Banded Roux-en-Y Gastric Bypass for the Treatment of Morbid Obesity’, published in Surgery for Obesity and Related Diseases (SOARD), concluded that the banded bypass procedure is safe and may provide better weight loss in super-obese patients. Bariatric News talked to one of the study’s authors, Dr Philip Schauer (Bariatric and Metabolic Institute, Cleveland Clinic, Cleveland, OH), about the study and benefits of the procedure…
What are the reasons for patients regaining weight after Roux-en-Y gastric bypass?
There are lots of reasons why people regain weight after a gastric bypass and one of the reasons maybe due to the dilation of the gastric pouch or the connection between the pouch and the small bowl (gastrojejunostomy). As the capacity of the pouch or gastrojejunostomy increases the sense of satiety decreases this result in patients eating more. The rationale behind the banded-bypass is to minimize the dilation thereby maintaining the size of the pouch or gastrojejunostomy.
We do not use this procedure on every patient, but usually on patients with a BMI >45. The problem with weight regain is much more pronounced in patients with a greater BMI, it is fairly uncommon to see significant weight regain in patients with BMI 35-45 who have a gastric bypass.
What is quite clear is that three, four, five years after the procedure, super obese patients regain a significant amount of weight. So if we can add a low cost, low risk device to enhance the weight loss all the better.
How does the band for the banded bypass differ from an adjustable gastric band?
Unlike an adjustable gastric band, once the band or ring is in place the stoma diameter is fixed. In addition, the ring is only 8 French in diameter allowing it to be removed easily by endoscopy which is usually not possible for the larger gastric band with a 1.5cm width. It is important to gauge the stoma diameter size and some of the literature suggests that the optimal length or circumference of the ring should be 6.5cm; this will usually result in an internal diameter of approximately 1.4-1.8 cm. There are some variable band lengths from 6.0cm to 7.0 cm that may be appropriate depending on patient factors such as gender and BMI. Generally 6.5cm seems to be a sufficient enough to enhance the weight loss without causing obstructive symptoms for most patients.
Were there any complications in your study?
When placing a ring, there are two significant complications that can occur. The first is erosion; this is when the ring itself migrates inside the stomach, it is not usually a severe problem because the ring can be removed endoscopically. This occurs in approximately 1% of patients, and in our study it occurred in two patients who were both treated successfully by endoscopic removal.
The other complication is migration; this is when the ring migrates down the stomach pouch potentially leading to obstruction of dysphagia. In such cases the ring is usually repositioned or removed surgically. In our study there were no instances of ring migration.
What were the key results from your study?
Our study showed that patients who had the ring, compared with similar patients who did not have the ring, have better weight loss. We found that the average excess weight loss at 24 months was 58.6% in the banded group compared with 51.4% in the bypass only group, a difference that was statistically significant. This translates to approximately 4-5 BMI points or 20-25lb weight loss advantage for the banded bypass.
Which device did you use?
The device that we used was made in the operating room with a piece of 8F silicon tubing. There are currently no FDA approved rings or bands approved for this kind of procedure in the US. Although, I know there are devices currently commercially available in Europe. However, the optimal technique and material have yet to be determined so we do need more detailed information from additional studies.
Where does the banded bypass lie in the armamentarium of the bariatric and metabolic surgeon?
Our study also refers to some previous studies and the lion’s share of evidence supports the use of a band to aid gastric bypass, as the benefit looks strong and the overall additional risk is fairly minor.