Single-Anastomosis Duodeno-Ileal Bypass with Sleeve Gastrectomy Model in Mice

So this protocol is the first description of CDS in mice, allowing us to mimic the surgery performed in clinical practice and to decipher the metabolic cellular and molecular mechanisms in a more predictable manner. This procedure requires less anastomosis than the gastric bypass, thus the operation is shortened and the survival rate is improved with similar metabolic benefits to the gastric bypass. Begin by administering buprenorphine, amoxicillin, metoclopromide, and iron subcutaneously.

From the xiphoid process, shave the first two thirds of the mouse's abdomen using an electric razor and disinfect the mouse's abdomen using an iodine povidone solution twice. Then place the mouse supine on a dedicated heat pad covered with a clean underpad. Check the depth of anesthetization using the toe pinch test, and cover the mouse in sterilized plastic wrap.

Next, hyper extend the mouse's abdomen by fixing the lower core and placing a one milliliter syringe or equivalent behind the mouse's back. Cut a window sized opening as the future incision site in a sterile compress, and use it as an operating field to cover the mouse. Perform a median laparotomy with scissors by opening the abdominal skin from the xiphoid process to the middle of the abdomen.

Then use scissors to open the abdominal wall along the linear alba between the abdominal muscles. Using a moistened cotton swab, gently mobilize the duodenum from the abdominal cavity to see its anterior and posterior sides. Then localized the main bile duct, which is immediately visible under the binocular microscope on the posterior side of the lesser omentum and the duodenum.

Under the binocular microscope, visualize an area approximately from the main bile duct between the duodenum arteries, and penetrate this area using curved micro forceps from one side of the duodenum to the other. Next, perform a duodenal negation between the arteries using a 6.0 non-absorbable suture. Use a moistened cotton swab and a non-traumatic clamp to mobilize the stomach from the abdominal cavity and separate it from the surrounding organs using micro scissors.

Then separate the greater omentum, cut the short gastric arteries between the stomach and the spleen and the lipoma linking the stomach to the lower part of the esophagus. Using micro scissors, perform a five millimeter gastrotomy by opening the fundus and removing the residual food using a cotton swab. Apply surgical clips along the stomach's greater curvature to exclude approximately 80%of the stomach, and remove the excluded stomach by cutting it with micro scissors.

Now, anchor the surgical clips to a certain impermeability by performing a running suture from the beginning to the end of the stomach resection. Under the binocular microscope, visualized the last ileal loop situated just before the cecum. Gently mobilized the small intestine outside the abdominal cavity from the last ileal loop, and dispose the small bowel so the last ileal loop is located on the left side.

Using a previously sized suture cord, measure 10 centimeters from the last ileal loop. To ensure that the future biliary limb comes to the anastomosis side from its left side, make a large loop of the small intestine around the side of the future anastomosis. At this point, perform a four millimeter enterotomy by opening the small bowel using micro scissors.

Perform a four millimeter enterotomy on the duodenum immediately after the pylorus between the stomach and the ligation performed earlier. Then place an absorbable hemostatic collagen compress to favor homeostasis. Using a non-absorbable 8.0 suture, perform a side to side duodenal ilealanal anastomosis starting from the posterior side to the anterior side, and display the small bowel in the abdominal cavity as described in the manuscript.

Rehydrate the mouse with 500 microliters of 37 degrees celsius saline solution by infusing it into the abdominal cavity using a one milliliter syringe. Now use a single 6.0 non-absorbable running suture to close the musculoaponeurotic neurotic layer, and close the abdominal skin using 6.0 non-absorbable separated sutures. After four weeks of intensive training, a progressive decrease in the operating time is observed, reaching approximately 60 minutes.

The five day post-operative survival also improved with time, reaching 77%during regular practice. From the fourth post-operative day, SADI-S mice experienced significant weight loss compared to the Sham mice. A significant increase in daily food intake was observed in SADI-S mice.

However, after iron supplementation, no significant difference was observed in the hemoglobin concentration between the Sham and SADI-S groups. When performing the anastomosis, it is crucial to dispose the bowel in a way that bile and food do not oppose each other to avoid an afferent loop syndrome.