The patient is positioned in the Trendelenburg position and tilted slightly to the left. A 30°, 10 mm conventional laparoscopic camera is used in the umbilical port site. Previously, we began the operation by performing an appendectomy because most open surgeons routinely did so to prevent confounding the anatomy if an appendectomy was needed later. Although performing an appendectomy did not add to our complication rate or duration of the procedure, we have stopped performing a routine appendectomy because of our experience with laparoscopic gastric bypass patients who rarely need an appendectomy after bariatric surgery. The diagnosis of appendicitis using computerized tomography is quite accurate, and since robotic duodenal switch results in minimal right lower quadrant adhesions in most patients, subsequent appendectomy should be straightforward.

We now begin by identifying the ileocecal junction and marking the ileum at 100 cm and 250 cm proximal to it with sutures. The bowel is then divided at the 250 cm mark using a linear cutter stapler and the mesentery is divided toward its root using the harmonic scalpel to mobilize the bowel. The bowel proximal to the 250 cm mark becomes the biliary limb and the bowel distal to it will become the alimentary limb. The biliary limb is then anastomosed to the ileum at the 100 cm mark using a 60 mm long conventional laparoscopic linear stapler. The enterotomies for the stapler are created using an ultrasonic shear and are closed using a single-layer running 2-zero suture using conventional intracorporeal laparoscopic suturing (Fig. 12.2).

The mesenteric defect between the biliary limb and the common channel is closed with running nonabsorbable sutures.

The patient is then placed in a reverse Trendelenburg position. A Nathanson liver retractor is placed through a stab incision near the xiphoid and used to elevate the left lobe of the liver. If the falciform ligament obscures visualization, it may need to be excised or we will sometimes attach it to the anterior abdominal wall.

Open surgeons have performed routine cholecystectomy in the past, and we continue to perform routine cholecystectomy for several reasons. The risk of gallstone formation is likely even higher than in gastric bypass patients due to the wasting of bile salts. There is no remnant stomach after BPD/DS, and the alimentary and biliopancreatic limbs are very long, making purely endoscopic techniques to retrieve common bile duct stones and ERCP essentially impossible. In addition, performing a cholecystectomy in the presence of scarring after a duodenoileostomy that lies immediately adjacent to the gallbladder is likely to be more difficult than after a RYGB where the anastomosis is in the left upper quadrant. The cholecystectomy is performed using standard laparoscopic techniques, although admittedly the procedure is made somewhat cumbersome by the port placement for the BPD/ DS.

The preparation for a sleeve gastrectomy begins by mobilizing the greater curvature of the stomach using an ultrasonic device. The mobilization is carried to the first part of the duodenum until the gastroduodenal artery is identified and the pancreas is noted to become adherent to the duodenum. The duodenum is then divided using a linear stapler giving the proximal duodenal stump a length of about 4 cm (Fig. 12.3).

The mobilization of the greater curvature of the stomach is then carried proximally inside the gastroepiploic arcade until the highest short gastric vessels are divided and the angle of His is exposed (Fig. 12.4). It is beneficial to detach any of the filmy adhesion between the posterior wall of the stomach and the pancreas to allow the stomach to be freely mobilized. Using the 34 French sizing tube as a guide, a sleeve gastrectomy is performed to create a stomach tube with a capacity of 150 ml s (Fig. 12.5).

The distal stomach is stapled with at least 4.8 mm leg length staplers (green loads), and as the stomach becomes less thick, the loads can be switched to a leg length of 3.5 mm. The use of staple-line reinforcements is optional. Our preference is to use robotic suturing with absorbable suture to oversew the distal stomach where it is thickest, and staples may not approximate the edges of the stomach. Particular care is taken to not narrow the stomach near the incisura. The central diaphragm is carefully inspected and any hiatal hernia identified is repaired.

The alimentary limb is then taken retrocolic to the right of the middle colic vessels and delivered close to the first part of the duodenum. The robot is then docked over the right shoulder (Fig. 12.6).

The camera is inserted through the umbilical port and a needle driver inserted through the left midclavicular port (arm 1). The second robotic arm is placed using a port-in-port technique through the right midclavicular port (arm 2), and the accessory arm is used through the right anterior axillary port (arm 3). The instruments on the right side are usually Cadiere graspers as this allows handling of the bowel and retraction on the suture. Arms 1 and 2 are used for suturing, whereas arm 3 is used for retraction of a stay suture that helps align the orientation of the enterotomies for suturing. The posterior seromuscular running layer is first started using running 2-zero nonabsorbable suture. An enterotomy is then made in the duodenum and in the ileum using the robotic hook cautery. A full-thickness running layer of 2-zero absorbable suture is started posteriorly and completed anteriorly. The anterior seromuscular layer of nonabsorbable suture completes the two-layer hand-sewn anastomosis (Fig. 12.7).