Bariatric Surgery

Abstract

The Roux-en-Y gastric bypass has taken on many forms over the last five decades. While it is still performed as an open procedure across much of the country, the laparoscopic variant has enjoyed increasing popularity among bariatric surgeons and patients since Clark and Wittgrove first described their technique in 1994. The advancement of the Roux limb may be performed in an antecolic/antegastric, retrocolic/antegastric, or retrocolic/retrogastric fashion. While each of these techniques has its own merits, it is advantageous for the practitioner to understand and be facile with each one; variations in patient anatomy as the situation presents may require the surgeon to diverge from his or her preferred approach.

General Description of Gastric Bypass

The Roux-en-Y gastric bypass has taken on many forms over the last five decades. While it is still performed as an open procedure across much of the country, the laparoscopic variant has enjoyed increasing popularity among bariatric surgeons and patients since Clark and Wittgrove first described their technique in 1994. The advancement of the Roux limb may be performed in an antecolic/antegastric, retrocolic/antegastric, or retrocolic/retrogastric fashion. While each of these techniques has its own merits, it is advantageous for the practitioner to understand and be facile with each one; variations in patient anatomy as the situation presents may require the surgeon to diverge from his or her preferred approach.

What is described below is our technique for a laparoscopic retrocolic Roux-en-Y gastric bypass. We recognize that there are many ways to “skin a cat,” with each resulting in an excellent outcome. While not described in this manuscript, we will often employ an antecolic approach based on the patient’s body habitus. We recognize, as well, that the use of a circular stapler placed transabdominally in order to create a stapled gastrojejunostomy is perfectly acceptable. However, this technique is not used in our practice. Furthermore, we now employ the DaVinci surgical robot for this procedure with the added advantage of enhanced visualization and intracorporeal dexterity. The technique of the procedure as described below, however, is the same regardless of the surgical approach.

Anatomy

Gastric anatomy is presented in Chap. 7, stomach.

Technique

Retrocolic Roux-En-Y Gastric Bypass

Diet prior to surgery:

We employ a 2-week modified protein liquid diet in order to reduce the size of the liver, which aids in the visualization of the gastroesophageal junction.

Tests prior to surgery:

H. pylori testing is mandatory. Postoperative gastric ulcers in the remnant stomach are not only quite morbid but also can be a diagnostic and treatment dilemma. We have not found bowel prep to be beneficial preoperatively.

Endoscopy:

Routine preoperative upper endoscopy to rule out gastroduodenal lesions which will not be approachable endoscopically once the remnant stomach has been bypassed. Preoperative endoscopy also will help to define posterior herniation of the fundus that may not be evident at the time of the operation and which can lead to suboptimal pouch construction.

• Step 1. The surgeon stands on the patient’s right side with an assistant on the left.

• Step 2. Prep and drape patient widely in anticipation of conversion to an open procedure if necessary.

• Step 3. Establish pneumoperitoneum in the normal manner. We prefer introduction of a Veress needle just below the left subcostal margin.

• Step 4. Enter the abdomen using a 5- or 10-mm optical viewing trocar 15–18 cm below the xiphoid and just to the left of the midline.

• Step 5. Place two ports on the patient’s right side: one just below the tip of the right lobe of the liver and the other in a line midway between the first port and the umbilicus. The second port should be a 12-mm port in order to accommodate a linear stapler.

• Step 6. Place one or two more assistant ports in the left upper quadrant.

• Step 7. Retract the left lobe of the liver anteriorly, using a Nathanson liver retractor placed through a small incision just below the xiphoid process.

• Step 8. Inspect the entire abdomen. Any adhesions should be carefully taken down.

• Step 9. Creation of Roux loop prior to the creation of the gastric pouch.

• Step 10. Identify the ligament of Treitz by retracting the greater omentum and transverse colon cephalad.

• Step 11. Using a linear stapling device, divide the small bowel 40 cm distal to the ligament of Treitz. A vascular load is preferred when stapling the small bowel in order to reduce the incidence of staple line bleeding.

• Step 12. To avoid ischemia of the two stapled ends, divide the mesentery for 4–5 cm in a direction perpendicular to the bowel (Fig. 22.1).

• Step 13. Create the Roux limb from the distal stapled bowel. We prefer a 120-cm Roux limb for patients with a BMI less than 50 and a 150-cm Roux limb for patients with a BMI greater than 50 kg/m² (Fig. 22.2).

• Step 14. An energy device is used to create an enterotomy on the antimesenteric border of the base of the Roux limb and near the stapled end of the proximal biliopancreatic limb.

• Step 15. Create a side-by-side isoperistaltic anastomosis by placing a linear stapler into these enterotomies. After deploying the stapler, it is wise to slightly close it while it is being removed from the bowel lumen to avoid unnecessarily widening the common defect (Fig. 22.3).

• Step 16. Close the common defect by aligning the edges of the bowel and deploying another staple load externally or by oversewing the defect with a single layer of running 2–0 absorbable suture.

• Step 17. The mesenteric defect must then be closed in order to prevent internal bowel herniation, which can be catastrophic. Close with a single running layer of nonabsorbable suture from the base of the mesenteric defect to the bowel. Care should be taken to avoid ligation of the small arterioles which may cause ischemia of the anastomosis (Fig. 22.4).

• Step 18. For a retrocolic Roux limb, the transverse mesocolon is held upright. A dimple can usually be seen just to the left of the middle colic vessels anterior to the ligament of Treitz. An energy device is used to open the mesocolon for about 2.5 cm and to create a window into the lesser sac.

• Step 19. Place the Roux limb into the lesser sac, with care taken to avoid twisting. This is best achieved by keeping the divided end of the mesentery oriented to the left.

• Step 20. Place the greater omentum and transverse mesocolon back into anatomic position.

• Step 21. Inspect the gastroesophageal junction. Excise the anterior fat pad with an energy device so that the angle of His can be dissected.

• Step 22. If a hiatal hernia exists, it is wise to dissect out the entire GE junction and repair it in the standard manner.

• Step 23. Construct the pouch by creating a defect in the lesser omentum 6 cm distal to the GE junction. Enter the lesser sac from the lesser curvature of the stomach (Fig. 22.5).

• Step 24. After ensuring that all transoral intragastric devices have been removed by the anesthesia team, create a horizontal staple line with a 45-mm standard GI load linear stapler 6 cm distal to the GE junction.

• Step 25. Inspect the posterior stomach. Take down any adhesions to the posterior lesser sac.

• Step 26. The anesthesia team places a 36-French bougie transorally to the level of the staple line. It will be used to protect the esophagus and to calibrate the size of the gastric pouch.

• Step 27. Carry the staple line cephalad through the angle of His. A complete division of the stomach must be ensured, because a gastrogastric fistula can lead to weight regain.

• Step 28. The Roux limb is brought out through an opening in the gastrocolic ligament in an antegastric fashion or brought out from behind the divided remnant stomach in a retrogastric fashion. Approximate the antimesenteric border near the stapled tip to the lower end of the gastric pouch

• Step 29. Use a single layer of running 2–0 absorbable suture to approximate the base of the pouch to the antimesenteric border of the Roux limb (Fig. 22.6).

• Step 30. Use an energy device to create 1-cm mirroring defects in the lower edge of the gastric pouch and the Roux limb anterior to the suture line.

• Step 31. Run a posterior layer of running 2–0 absorbable suture to approximate the posterior edges of the gastrojejunostomy.

• Step 32. Run the anterior inner layer of the gastrojejunostomy with a second 2–0 absorbable suture. Advance the 36-French bougie across the anastomosis into the small bowel in order to calibrate the size of the stoma (Fig. 22.7).

• Step 33. Finally, a second anterior layer of running 2–0 absorbable suture is run in a Lembert fashion to complete the two-layer anastomosis.

• Step 34. Test the integrity of the anastomosis . Clamp the Roux limb just distal to the anastomosis. With the anastomosis submerged in saline, either infuse methylene blue through an orogastric tube or perform upper endoscopy to insufflate the pouch. The latter technique allows the surgeon to rule out an intraluminal anastomotic bleed, which can be immediately controlled by oversewing.

• Step 35. With a competent anastomosis, surgical drains are typically not left in place unless there is a concern with the tissue’s ability to heal.

• Step 36. In the case of a retrocolic Roux limb, the underside of the transverse mesocolon is again inspected. In order to prevent problems with poor emptying, gently reduce any redundant bowel back below the mesocolic defect. Close the defect by running a 2-0 permanent suture to approximate the cut edges of the transverse mesocolon, the bowel. Take care to include the entire Peterson defect, which can be found on the patient’s right side just below the site of entrance of the bowel through the mesocolic defect.

• Step 37. The greater omentum and transverse mesocolon are again placed back in anatomic position. In order to prevent injury to the spleen or the newly formed gastrojejunostomy, carefully remove the liver retractor under direct visualization

• Step 38. Remove the trocars. The carbon dioxide is completely expelled from the abdominal cavity (Fig. 22.8).

Fig. 22.1

The small bowel is divided using a linear stapler. Two more firings of the stapler are used to divide the mesentery. This provides additional mobility for the Roux limb

Fig. 22.2

Creation of the Roux limb

Fig. 22.3

After the Roux limb is measured, it is approximated to the biliopancreatic limb. Enterotomies are made. A linear stapler is used to create the anastomosis

Fig. 22.4

Closure of mesenteric defect

Fig. 22.5

Creation of gastric pouch

Fig. 22.6

The Roux limb is approximated to the gastric pouch

Fig. 22.7

Completing the anastomosis. Inset: Common opening is closed

Fig. 22.8

Completed Roux-en-Y gastric bypass

Postoperative

• Pain control is generally not an issue postoperatively. Pain is generally well controlled with a PCA (patient-controlled analgesia) device that can be removed the morning following surgery and replaced with a liquid narcotic for a few days.

• A Foley catheter, placed after induction of anesthesia, is left overnight to monitor urine output. It is removed the morning following surgery.

• Unless there is concern about the anastomosis, patients are allowed ice chips on the night of surgery and started on a sugar-free clear liquid diet on the morning of post-op day 1.

• We do not employ swallow studies routinely. There is a well-published 50% false-negative rate for these studies. Intraoperative testing of the anastomosis should be all that is needed to ensure a competent suture line.

• Patients should ambulate as early as the night of surgery and be kept on subcutaneous DVT (deep vein thrombosis) prophylaxis throughout the hospital stay.

• In our practice, any patient with a history of DVT, pulmonary embolism, or with a BMI of 50 kg/m² or greater is sent home on subcutaneous anticoagulation for 1 week.

• Patients who are tolerating liquids without nausea and ambulating may be discharged home on postoperative day 1 or 2.

• Patients are kept on a liquid diet for 1 to 2 weeks post-op. This diet consists of liquid protein supplementation, sugar-free fluids , and chewable vitamins.

Laparoscopic Vertical Sleeve Gastrectomy

Anesthesia: General

Patient Positioning

• 1. Patient in the supine position with both arms out.

• 2. Footboard secured to bed.

• 3. Care is taken to ensure that the patient’s heels are on the footboard with toes out, to minimize the risk of ankle subluxation when in the standing position.

• 4. Surgeon stands on the patient’s right with assistant on the left.

Other: Foley catheter, orogastric tube, and sequential compression devices

• Step 1. Prep and drape in standard fashion for either open or laparoscopic access.

• Step 2. Administer perioperative cephalosporin and low-molecular-weight heparin in the pre-op holding area.

• Step 3. Establish carbon dioxide pneumoperitoneum to 15-mm Hg with a Veress needle inserted in the left subcostal margin.

• Step 4. Enter abdomen with a 12-mm optical viewing trocar just left and superior to the umbilicus.

• Step 5. Port position as shown : Assistant 5-mm port in the left mid-abdomen, 15-mm port in the right mid-abdomen, and 5-mm port in the right upper quadrant. Subxiphoid incision for the hook liver retractor.

• Step 6. Once trocars are in position, patient is placed in slight reverse Trendelenburg. The liver retractor is fixed to the bed with a mechanical arm.

• Step 7. Dissection begins on the greater curve of the stomach 5 cm proximal to the pylorus. This is usually in the area of the insertion of the right gastroepiploic artery.

• Step 8. All of the gastrocolic, gastrosplenic (short gastric vessels), and gastrophrenic attachments are divided using a harmonic scalpel, ligasure, or enseal device depending upon surgeon preference. The most cephalad aspect of the dissection on the greater curve is complete when the left crus is identified.

• Step 9. Inspect the hiatus for a hiatal hernia.

• Step 10. If a hiatal hernia is encountered, the hiatus is circumferentially mobilized, and a posterior cruroplasty is performed with interrupted 0-Ethibond sutures. Use a 60-Fr bougie to calibrate the posterior cruroplasty (if performed).

• Step 11. A 36-Fr round, non-tapered tip bougie is advanced and situated along the lesser curve of the stomach. Take care to ensure that there is no orogastric tube or esophageal temperature probe in the patient’s mouth at this time to eliminate the risk of accidental division of these tubes when the stomach is divided.

• Step 12. Starting 5 cm proximal to the pylorus on the greater curve of the stomach, use a surgical stapler to begin the vertical gastrectomy. We routinely start with the 4.1-mm-thick tissue loads and transition to the 3.8- or 3.5-mm tissue loads. Often, we also use tissue reinforcement (although this is still debatable) (Fig. 22.9).

• Step 13. The vertical gastrectomy continues, using the bougie as a guide. Care is taken to avoid narrowing the gastric pouch at the incisura. Care is also taken at the most cephalad aspect approaching the gastroesophageal junction to not hug the bougie, in order to avoid an inadvertent side bite on the distal esophagus.

• Step 14. Perform an on-table leak test. Options include an air leak test using an endoscope, a saline submersion leak test, or a dye leak test. If the leak test is negative, we do not routinely perform a post-op day 1 upper GI series, unless it is clinically indicated.

• Step 15. The portion of the stomach to be removed is placed in an endocatch bag and removed via the 15-mm trocar site.

• Step 16. Remove all trocars under direct vision. Close the 15-mm fascial incision with 0 vicryl (Fig. 22.10).

Fig. 22.9

The stapler is fired successively from the antrum to the angle of His adjacent to an intragastric bougie

Fig. 22.10

Completed laparoscopic sleeve gastrectomy

Postoperative

• Patients begin ambulating the evening of surgery.

• Ice chips are allowed immediately following surgery.

• The patient is advanced to a liquid diet postoperative day 1. Patients are discharged home if they are able to tolerate at least 4 ounces of liquids per hour.

Biliopancreatic Diversion with Duodenal Switch

This section outlines our technique for performing the biliopancreatic diversion with duodenal switch (BPD-DS) . This is a procedure we offer patients with a body mass index in the range of 55 to 70 kg/m2. We feel that patients with a BMI below that range will find success with a less aggressive procedure and patients with a BMI above 70 will be counseled to undergo a staged procedure beginning with a sleeve gastrectomy with a later conversion to either the BPD-DS or gastric bypass once they have lost down to a weight that will reduce their operative risk. Recognizing that this operation is widely performed in both the open and minimally invasive techniques . We have described the procedure as it may be performed by either method. Our technique begins very deliberately with the sleeve gastrectomy. With this portion safely completed, we then move to the distal enteroenterostomy. We leave division of the duodenum with the duodeno-enterostomy as a final step.

It is important that patients understand, prior to choosing this procedure, that it will necessarily entail lifelong vitamin supplementation. Patients who forgo the prescribed supplements will most certainly find themselves with significant nutrient deficiencies. We prescribe three bariatric multivitamins, calcium, vitamin D, iron, and B12. Nutritional labs are checked twice a year, and the patients are seen by our dietician every 6 months. When managed conscientiously by the patient, physician, and weight loss team, this operation can yield an excellent result in larger patients who might otherwise find more moderate results with the sleeve gastrectomy or gastric bypass procedures.

• Of the commonly performed bariatric procedures today, the biliopancreatic diversion with duodenal switch stands as the most aggressive procedure with regard to weight loss and the resolution of comorbid, metabolic conditions. This operation has been shown to result in the most significant weight loss and the least amount of weight regain when compared to the gastric bypass or sleeve gastrectomy. It is important to note that the anatomy of this operation will decrease the patient’s ability to absorb dietary fats as well as fat-soluble vitamins. This will necessitate a very stringent lifelong course of vitamin supplementation, and the patient should be well aware that lifelong nutritional monitoring will be required. Below is our technique for performing this procedure. Please note that the common approaches to performing this procedure are (1) through the standard open technique, (2) laparoscopically, or (3) robotically. Whatever route is chosen for surgical access, the procedure performed remains the same. Some of the most salient points to remember in this brief description are the lengths of the common and alimentary channels as well as the technique for creating the sleeve gastrectomy, which may very somewhat from a standard vertical sleeve gastrectomy when performed alone. Our preference is to perform a hybrid laparoscopic/robotic technique as described below.

  • The patient is placed in the supine position with the arms out.

  • All pressure points are padded. A Foley catheter is placed following induction of general anesthesia.

  • The abdomen is prepped and draped to allow wide access to the entire abdominal cavity from the xiphoid to well below the umbilicus.

• Step 1. Initial access is gained about 25 cm below the xiphoid just to the left of center using an optical viewing trocar .

  • Upon gaining access, the abdomen is insufflated, and general inspection was undertaken to ensure that there are no gross, visual abnormalities, or significant adhesive disease.

  • Significant adhesive disease from prior surgery may require prolonged lysis, conversion to an open technique, or transition to performing a sleeve gastrectomy only.

• Step 2. Placement of trocars (Fig. 22.11)

  Trocars are then placed under direct visualization in the right upper quadrant just below the tip of the right lobe of the liver. A “stapling” trocar is then placed between this right upper quadrant trocar and the umbilicus. A fourth port is then placed in the left upper quadrant.

• Step 3. A liver retractor is placed through a stab incision just below the xiphoid in order to retract the left lobe of the liver anteriorly.

• Step 4. Sleeve gastrectomy is performed. Refer to technique earlier in this chapter.

  Our procedure begins with the creation of the sleeve gastrectomy.

  • This is typically done by using either an ultrasonic dissector or monopolar device to dissect the omentum from the greater curvature of the stomach.

  • As in the case of a typical sleeve gastrectomy, care should be taken to perform this dissection as close to the stomach as possible in order to avoid injury to the gastroepiploic epiploic vessels.

    • Injury to these vessels could cause bleeding or, possibly, thrombosis of the portal vein.

  • The dissection is carried up to the level of the left crus of the diaphragm.

    • If a hiatal hernia is noted. We recommend repairing it in the typical standard fashion.

  • With the greater curvature now fully mobilized, a bougie is placed transorally down to the level of the pylorus in order to calibrate the size of the sleeve. We will typically use a larger bougie, than we would with a standard sleeve gastrectomy. Either a 56- or 60-French bougie are commonly used when performing the BPD-DS.

  • A staple line is started on the greater curvature, 6 cm proximal to the pylorus, and a linear stapler is used to divide the stomach along the bougie up through the cardiac angle of the stomach.

  • The bougie is then removed. A leak test will be performed at the conclusion of the procedure.

• Step 5. Duodenal dissection

  With the sleeve gastrectomy now completed, attention is turned to the duodenal dissection.

  • The duodenum is dissected from its retroperitoneal position using an energy device. Care must be taken to do this slowly and deliberately as there is a complex of small vessels just below the first portion of the duodenum which could easily bleed, obscuring the field and making the dissection more precarious. If needed, the pylorus can be marked prior to this dissection with a single stitch as it is sometimes somewhat more difficult to identify after the dissection has been completed. During this portion of the dissection, extra care must be taken to avoid injury to the gastroduodenal artery and common bile duct which lie just posterior to the first and second portions of the duodenum.

  • Once these structures have been identified, a window can be made through the fat overlying the cephalad portion of D1 so that a stapler can be placed across. We generally reserved this portion of the case until after we have made our enteroenterostomy.

• Step 6. Creation of enteroenterostomy (Fig. 22.12)

  • We find it helpful to place a 12-mm trocar just to the left of midline below the umbilicus. The camera is now placed in the left upper quadrant trocar, and instruments are placed through the prior camera port and infraumbilical trocar.

  • The terminal ileum is identified, and the ileum is measured proximally 100 cm.

    • This will be the common limb and is marked with clips.

    • We placed two clips proximally and one distally to mark the direction of “downhill” flow.

  • From this point, we measure another 150 cm proximally where the small bowel is divided with a vascular linear stapler.

  • We mark the tip of the alimentary limb with several clips in order to avoid confusion when making our anastomosis.

  • The mesentery is divided using an energy device to decrease tension on the alimentary limb.

  • The tip of the more proximal, biliopancreatic limb is then placed next to our previously placed clips on the common channel 100 cm from the ileocecal valve.

  • We place a stay suture on the tip of the biliopancreatic limb and the common limb and make enterotomies on the antimesenteric side of each. We then perform a side-by-side anastomosis with two firings of the 60-mm vascular load linear stapler. The common defect can then be oversewn or closed with another staple fire.

  • The mesenteric defect is then closed with a running 2-0 silk suture.

    • At this point, the alimentary limb is brought up to the duodenum. If needed, the omentum can be divided to create less tension on the duodeno-enterostomy.

• Step 7. Division of duodenum and creation of duodeno-enterostomy (Figs. 22.13, 22.14, and 22.15)

  At this point, we’ll proceed with dividing the duodenum. This is typically done with a linear stapler. We choose to use staple reinforcement for this staple fire.

  • The duodenal stump may be oversewn, but this is not our typical practice.

  • The tip of the alimentary limb is then placed in an end to side fashion next to the stapled tip of the duodenum.

  • These two structures are then approximated with a running 2-0 silk suture.

  • An anterior duodenotomy and enterotomy are then made. We tend to try to make these enterotomies as wide as possible to avoid a stenosis of the enteroenterostomy. Because the pylorus is intact, we do not try to keep this anastomosis, narrow as we typically would in a gastric bypass.

  • We then hand sew the posterior and anterior layers using a running 3-0 absorbable suture.

  • Until you have developed a lot of experience with this, we recommend sewing this anastomosis over a stent to ensure the patency of the anastomosis. This can easily be done using the standard gastroscope which will facilitate in testing the anastomosis and the sleeve postoperatively.

  • Once the posterior and anterior layers have been sewn together, we run a final layer in a Lembert fashion using another 3-0 absorbable suture.

• Step 8. Testing for a leak

  The sleeve and anastomosis are then stressed with air from a gastroscope. The gastroscope allows us to visualize any internal bleeding from the staple line or leaks that may be occurring at the anastomosis or along the staple line.

  • Leaks can generally be managed with single interrupted absorbable sutures.

  • It is sometimes recommended to close the large mesenteric defect created by the antecolic passage of the alimentary limb, although this has not typically been our practice.

  • Following a negative leak test, a 10-French flat JP drain is placed so that it is in proximity to the staple line, the duodeno-enterostomy, and the duodenal stump.

  • This may be removed the next day, if the patient is tolerating liquids and no bilious effluent is seen in the drain.

• Step 9. Remove gastric remnant and trocars.

  Remove the resected portion of the stomach using a retrieval bag.

  • The liver retractor should be removed under direct visualization.

  • The abdomen is deflated, the trocars are removed, and the sites are closed in standard fashion.

Fig. 22.11

Sites of incisions and ports

Fig. 22.12

(a–e) Creation of duodena-duodenostomy

Fig. 22.13

Division of duodenum

Fig. 22.14

(a, b) Creation of duodeno-enterostomy

Fig. 22.15

Completed operation showing the duodenal switch and all anastomoses

Post-op

Our patients will generally stay one to two nights on the bariatric floor of the hospital.

• We began feeding them clear liquids the next morning.

• We do not routinely perform fluoroscopic swallow studies unless the patient is having significant nausea lasting more than 48 h or there is concern for a leak.

• Any bilious material that is seen in the drain on postoperative day 1 should be treated as a leak from the duodenal stump and should necessitate a diagnostic laparoscopy.

• The patients are sent home on a full liquid diet for 2 weeks and then advanced over the course of the next few weeks to a regular diet.

• We will generally check nutritional laboratories often in the first year at 3 months, 6 months, and in 12 months.

• Nutrition should also be checked annually or semiannually to ensure that proper supplementation is being maintained.

• It is very important that the patient take a vitamin that has the adequate amount of vitamins A, D, E, and K, as these are difficult for the patient to absorb following this procedure.