Sleeve gastrectomy, gastric bypass, gastric banding, and duodenal switch are the most common bariatric procedures performed worldwide. Ninety-five percent of bariatric operations are performed with minimally invasive laparoscopic technique. Perioperative morbidities and mortalities average around 5% and 0.2%, respectively. Long-term weight loss averages around 15% to 25% or about 80 to 100 lbs (40–50 kg). Comorbidities, including type 2 diabetes, hypertension, dyslipidemia, sleep apnea, arthritis, gastroesophageal reflux disease, and nonalcoholic fatty liver disease, improve or resolve after bariatric surgery.
Key points
- •
Sleeve gastrectomy, gastric bypass, gastric banding, and duodenal switch are the most common bariatric procedures performed worldwide.
- •
Ninety-five percent of bariatric operations are performed with minimally invasive laparoscopic technique.
- •
Perioperative morbidities and mortalities average around 5% and 0.2%, respectively.
- •
Long-term weight loss averages around 15% to 25% or about 80 to 100 lbs (40–50 kg).
- •
Comorbidities, including type 2 diabetes, hypertension, dyslipidemia, sleep apnea, arthritis, gastroesophageal reflux disease, and nonalcoholic fatty liver disease, improve or resolve after bariatric surgery.
Introduction
Bariatric surgery has evolved since the 1950s and has proven to be the most effective long-term treatment for the chronic disease known as obesity. Furthermore, it also has been shown to resolve or significantly improve many of the metabolic disorders related to obesity, especially type 2 diabetes (T2D). These gastrointestinal procedures have resulted in resolution of obesity-related comorbidities through weight loss, neuroendocrine, or hormonal mechanisms. Thus, the term bariatric surgery is now frequently replaced with metabolic surgery. A complete understanding of all the mechanisms of metabolic surgery is yet to be determined. It is known, however, that the alteration of the gastrointestinal tract by reducing stomach capacity and nutrient absorption in the small intestine alters the satiety, calorie absorption, and neuroendocrine pathways, leading to sustained weight loss and resolution of T2D.
The laparoscopic technique of bariatric/metabolic surgery was started in the early 1990s, and currently, almost 95% of these metabolic procedures are performed laparoscopically worldwide. The laparoscopic approach significantly reduces perioperative morbidity, mortality, recovery time, and cost. In 2015, a total of 196,000 bariatric/metabolic procedures were performed in the United States, and sleeve gastrectomy (SG) was the commonest metabolic procedure (53.8%). Other metabolic procedures were Roux-en-Y gastric bypass (RYGB), 23.1%; laparoscopic adjustable gastric band (LAGB), 5.7%; biliopancreatic diversion with or without duodenal switch (BPD ± DS), 0.6%; and revisional and other procedures, 16.8%.
Bariatric surgery was initially introduced as weight-loss surgery for the treatment of severe obesity. Obesity is most commonly measured based on body mass index (BMI), which has been used as the primary indication for bariatric surgery. The 1991 National Institutes of Health (NIH), 2013 American College of Cardiology/American Heart Association Task Force, and The Obesity Society (TOS) have similar guidelines for bariatric surgery referral: BMI greater than or equal to 40 kg/m 2 or BMI greater than or equal to 35 kg/m 2 with obesity-related comorbidities. It is becoming increasingly evident that BMI itself is not necessarily a strong marker for obesity-related illness or future cardiovascular risk. It appears that fat distribution and quantity of visceral fat rather than BMI alone convey the major risk factors for obesity. Metabolic surgery in patients with T2D should be tailored based on the class of obesity and inadequate glycemic control despite optimal medical treatment. Based on strong evidence from randomized trials, metabolic surgery was recently recommended in the treatment algorithm for T2D in the 2nd Diabetes Surgery Summit (DSS-II).
Introduction
Bariatric surgery has evolved since the 1950s and has proven to be the most effective long-term treatment for the chronic disease known as obesity. Furthermore, it also has been shown to resolve or significantly improve many of the metabolic disorders related to obesity, especially type 2 diabetes (T2D). These gastrointestinal procedures have resulted in resolution of obesity-related comorbidities through weight loss, neuroendocrine, or hormonal mechanisms. Thus, the term bariatric surgery is now frequently replaced with metabolic surgery. A complete understanding of all the mechanisms of metabolic surgery is yet to be determined. It is known, however, that the alteration of the gastrointestinal tract by reducing stomach capacity and nutrient absorption in the small intestine alters the satiety, calorie absorption, and neuroendocrine pathways, leading to sustained weight loss and resolution of T2D.
The laparoscopic technique of bariatric/metabolic surgery was started in the early 1990s, and currently, almost 95% of these metabolic procedures are performed laparoscopically worldwide. The laparoscopic approach significantly reduces perioperative morbidity, mortality, recovery time, and cost. In 2015, a total of 196,000 bariatric/metabolic procedures were performed in the United States, and sleeve gastrectomy (SG) was the commonest metabolic procedure (53.8%). Other metabolic procedures were Roux-en-Y gastric bypass (RYGB), 23.1%; laparoscopic adjustable gastric band (LAGB), 5.7%; biliopancreatic diversion with or without duodenal switch (BPD ± DS), 0.6%; and revisional and other procedures, 16.8%.
Bariatric surgery was initially introduced as weight-loss surgery for the treatment of severe obesity. Obesity is most commonly measured based on body mass index (BMI), which has been used as the primary indication for bariatric surgery. The 1991 National Institutes of Health (NIH), 2013 American College of Cardiology/American Heart Association Task Force, and The Obesity Society (TOS) have similar guidelines for bariatric surgery referral: BMI greater than or equal to 40 kg/m 2 or BMI greater than or equal to 35 kg/m 2 with obesity-related comorbidities. It is becoming increasingly evident that BMI itself is not necessarily a strong marker for obesity-related illness or future cardiovascular risk. It appears that fat distribution and quantity of visceral fat rather than BMI alone convey the major risk factors for obesity. Metabolic surgery in patients with T2D should be tailored based on the class of obesity and inadequate glycemic control despite optimal medical treatment. Based on strong evidence from randomized trials, metabolic surgery was recently recommended in the treatment algorithm for T2D in the 2nd Diabetes Surgery Summit (DSS-II).
Patient selection for metabolic surgery
Indications for bariatric surgery are based on the historic 1991 NIH Consensus Guidelines. These guidelines focused primarily on surgery as treatment of severe obesity, but not necessarily for those with T2D and obesity-related metabolic diseases. In general, patients with chronic obesity and BMI greater than or equal to 40 or BMI greater than or equal to 35 with comorbidity are candidates for surgery if they are psychologically stable and have no active substance abuse. Recently, the DSS-II in collaboration with 6 International Diabetes Organizations published a joint statement on the treatment algorithm for T2D using metabolic surgery. This joint statement was endorsed by 45 leading professional societies worldwide (including both medical and surgical organizations). The indications and contraindications for metabolic surgery are shown in Table 1 .
| Indication (BMI depends on patients’ ancestry; Asians: BMI should be reduced by 2.5 kg/m 2 ) |
|
| Contraindication |
|
Metabolic surgery should be performed in high-volume centers with a multidisciplinary team (including the surgeon, endocrinologist/diabetologist, and dietician with expertise in diabetes care). Other relevant specialists should be considered depending on the patients’ circumstances.
Preoperative evaluation of these patients includes a complete medical history, psychological history, nutritional assessment, physical examination, and investigations to assess surgical risk for metabolic surgery (endocrine, metabolic, nutritional, and psychological assessments). In 2008, American Association of Clinical Endocrinologists (AACE), TOS, and American Society for Metabolic and Bariatric Surgery (ASMBS) published clinical practice guidelines (CPG) for perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patients, which was recently updated in 2013. Patients should have a comprehensive preoperative assessment of all comorbid conditions. For patients with diabetes, they should be counseled regarding frequent postoperative monitoring of glycemic control, diabetic complications (diabetic ketoacidosis or hypoglycemia), the likelihood of diabetes remission, and complementary medical therapy.
The choice of the metabolic procedure is based on the risk-to-benefit-ratio evaluation for each patient. Long-term postoperative complications of surgery versus effectiveness of glycemic and cardiovascular risk should be discussed with each patient as part of informed consent. Currently, 4 procedures constitute most bariatric operations globally: SG, RYGB, LAGB, and BPD + DS ( Fig. 1 ).
Technique of the procedures
Patient preparation in the operating room is summarized in Table 2 . The position of the operating surgeon and the assistant is as shown in Figs. 2 , and 3 shows the port placement for all the bariatric procedures in the authors’ center.
| Positioning |
|
| Prophylactic antibiotics |
|
| VTE prophylaxis |
|
Approach
Liver retraction
A 5-mm liver retractor (Snowden-Pencer, Tucker, GA, USA) is placed through the right lateral port and anchored to the bed with a self-retaining device. A Nathanson liver retractor can also be used in the subxiphoid position and, for larger patients with extremely big or floppy left hepatic lobes, both retractor systems can be used simultaneously to achieve adequate exposure of the gastroesophageal junction.
Operative Procedures
Sleeve gastrectomy
- •
Mobilize the omentum at stomach’s greater curvature from the angle of His all the way down to the pylorus using the ultrasonic dissector device.
- •
Create stomach tube ( Fig. 4 A ).
- ○
Once the stomach is fully mobilized, apply a 60 mm load stapler approximately 3 cm to the pylorus, parallel to the lesser curvature. An endoscope is passed down along the lesser curvature of the stomach and into the pylorus. Continue to fire 60 mm load staplers parallel to the endoscope up toward the angle of His.
Fig. 4
The laparoscopic SG. ( A ) Creating a narrow gastric tube over a bougie or endoscope using a linear cutting stapler to excise the stomach body and fundus. ( B ) The final anatomic arrangement after a SG.
( Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography © 2006-2016. All Rights Reserved.)
- ○
- •
Oversewn stapler lines
- ○
The long stapler lines are oversewn with running a 2-0 absorbable suture in a Lembert fashion all the way down to the pylorus. Alternatively, some surgeons will reinforce the staple line with a synthetic buttressing material or provide no additional reinforcement. Fig. 4 B shows the final anastomotic arrangement after SG.
- ○
- •
Leak test
- ○
With the scope in place, insufflation of stomach is performed to test for air leaks and narrowing.
- ○
- •
Schauer’s cap
- ○
An omental patch is placed over the anastomosis and secured with 2-0 nonabsorbable suture.
- ○
- •
Liver biopsy
- ○
A core needle liver biopsy using an 18-G needle is performed routinely as part of every bariatric procedure to document the severity of nonalcoholic fatty liver disease (NAFLD).
- ○
- •
Drain (optional)
- ○
A round Jackson-Pratt (JP) drain is placed alongside the staple/suture line and brought out through the right upper quadrant port site.
- ○
- •
Specimen retrieval (SG)
- ○
A remnant stomach specimen is removed using a sterile bag.
- ○
- •
Port closure
- ○
Close fascia at the 12-mm port sites with absorbable suture using a suture-passer.
- ○
- •
Skin closure
- ○
All instruments and trocars are removed. The abdomen is deflated.
- ○
Skin incisions are closed with subcuticular 4-0 absorbable suture.
- ○
- •
Sterile dressings are applied.
Adjustable gastric band
- •
Gastrohepatic ligament window creation
- ○
After adequate exposure of the gastroesophageal junction, the peritoneum overlying the angle of His is divided with a Harmonic scalpel. The pars flaccida is opened, and the base of the right crus is identified.
- ○
- •
Before the gastric band is placed, the band, its tubing, and port are tested for no leak and functioning well.
- •
Band placement ( Fig. 5 A )
- ○
An opening is created at the base of the right crus, and the articulating band passer device is passed through the retrogastric tunnel to the left side and held in place. The band is then placed in the abdominal cavity and attached to the band passer. Once the band is placed well, it is then locked around the upper portion of the stomach.
Fig. 5
The LAGB. ( A ) Passing the adjustable gastric band behind the posterior stomach wall through a window in the gastrohepatic ligament (pars-flaccida technique). ( B ) Placing a few loose, simple interrupted plication sutures over the band anteriorly to reduce risk of band slippage and stomach herniation.
( Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography © 2006-2016. All Rights Reserved.)
- ○
- •
Stomach-band stay suture (see Fig. 5 B)
- ○
Two gastrogastric plication sutures are placed using 0 silk sutures, and the removable attachment of the band is then removed through the 15-mm trocar site.
- ○
- •
Port placement
- ○
A subcutaneous pocket is created at the right paramedian 15-mm trocar site. The band tubing is brought out through that opening. The fascia is cleared inferior and lateral to the exit site, and the tubing is pushed into the abdomen without any tension. The port applicator is used to secure the port to the fascia so it is held in good position.
- ○
- •
Final laparoscopic inspection to look for the band position; no kinks or twisting of the tubing.
Roux-en-Y gastric bypass
Roux-en-Y gastric bypass is one of the commonest metabolic surgery performed with excellent weight loss and metabolic disease improvement ( Fig. 6 ).
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
