- The two most common bariatric procedures are Roux-en-Y gastric bypass and vertical sleeve gastrectomy (often performed laparoscopically), which provide clinically meaningful improvement in metabolic diseases such as type 2 diabetes mellitus.
- Gastric bypass involves dividing the stomach into a small proximal gastric pouch (leaving a large “bypassed” gastric remnant in situ) attached to a “roux” limb of small bowel jejunum, bypassing the larger gastric remnant, all of the duodenum, and a portion of the proximal small intestine.
- Acute complications of gastric bypass include leaks or perforations potentially leading to peritonitis with severe abdominal pain, fever, tachycardia, and leukocytosis. Imaging may include soluble contrast for abdominal CT or upper GI study (not barium). Treatment is immediate surgical exploration.
- Chronic complications of gastric bypass include:
- Gastro-gastric fistula, resulting in an increased capacity to ingest food and suboptimal weight loss or weight regain.
- Dumping syndrome, resulting in facial flushing, lightheadedness, reactive hypoglycemia, and postprandial diarrhea.
- Internal hernia can occur with gastric bypass, with intermittent postprandial pain and emesis.
- Sleeve gastrectomy involves removing a portion of the stomach, leaving less stomach area and altering gastrointestinal hormones.
- Acute complications of sleeve gastrectomy include: Gastrointestinal obstruction and staple line leaks.
- Chronic complications of sleeve gastrectomy include: sleeve dilation, gastrointestinal reflux disease and luminal stenosis/strictures.
- Acute complications that can accompany abdominal surgery include:
- Infection, dehydration, cardiac dysrhythmias, atelectasis and pneumonia, deep vein thrombosis, and pulmonary emboli.
Bariatric Surgical Procedures
|Pros||Cons||Expected loss in percent excess body weighta at two years||Optimally suited for patients with:||Other comments|
|Roux-en-Y Gastric Bypass||Greater improvement in metabolic disease||Increased risk of malabsorptive complications over sleeve||60–75%||Higher BMI, GERD, Type 2 DM||Largest data set, more technically challenging than LAGB, VSG|
|Vertical Sleeve Gastrectomy||Improves metabolic disease; maintains small intestinal anatomy; micronutrient deficiencies infrequent||No long-term data||50–70% (3- year dataa)||Metabolic disease||Can be used as the first step of staged approach; most common based on 2014 data|
|Laparoscopic Adjustable Gastric Banding||Least invasive; removable||25–40% 5 year removal rate internationally||30–50%||Lower BMI; no metabolic disease||Any metabolic benefits achieved are dependent on weight loss|
|Biliopancreatic Diversion with Duodenal Switch||Greatest amount of weight loss and resolution of metabolic disease||Increased risk macro- and micronutrient deficiencies over bypass||70–80%||Higher BMI, Type 2 DM||Most technically challenging; VSG followed by anastomoses|
|Loop Duodenal Switch||May be simpler & safer than BD-DS with less micronutrient deficiencies||Long-term data not available||70–80%||Higher BMI, Type 2 DM||Two step procedure: VSG followed by single anastomosis|
|Hospital stay||1–4 days||1–2 days||Outpatient procedure||2–4 days|
|Recovery||1–2 weeks||1–2 weeks||Usually one week||2–4 weeks|
|Poor surgical candidate||✓||✓||✓||✓|
|Severe psychiatric disorder||✓||✓||✓||✓|
|Intolerance to general anesthesia||✓||✓||✓||✓|
|Drug or alcohol addiction||✓||✓||✓||✓|
|Untreated gastric ulcer||✓||✓||✓||✓|
|Previous gastric bypass||✓|
|Irritable bowel syndrome||✓|
|Patient demonstrates an unwillingness or an inability to follow long term recommendations which can lead to life threatening micronutrient deficiencies.||✓|
|Patient demonstrates an unwillingness or an inability to follow/afford long-term recommendations (e.g., blood testing and postoperative vitamins) which can lead to life threatening micronutrient deficiencies.||✓|
|Acute gout exacerbation||✓||✓|
|Atelectasis and pneumonia||✓||✓||✓||✓|
|Band too tight with gastrointestinal obstructive symptoms (i.e., dysphagia)||✓|
|Deep vein thrombosis||✓||✓||✓||✓|
|Staple line leaks||✓|
Other FDA-approved Bariatric Technologies
- Aspiration Therapy via Modified Percutaneous Endoscopic Gastrostomy (PEG)
- Mechanism: Drains 30% of ingested meal
- Indication: Body mass index 35–55 kg/m2
- Efficacy: 12% excess weight loss at one year
- Safety: Potential tube site inflammation/infection
- Electrical Vagal Blocking System
- Mechanism: Pacemaker-like implantable device surgically placed under skin, with lead wires placed around the vagus nerve just above the stomach. Blocks vagal impulses to brain resulting in decreased hunger and increased satiety
- Indication: Body mass index >40 kg/m2 or >35 kg/m2 among those with adverse consequences of obesity
- Efficacy: 8.5% excess weight loss
- Safety: Potential gastroparesis (vagal trunk injury or entrapment)
- Intragastric Balloons
- Mechanism: Balloon is inserted into stomach and filled
- Indication: Body mass index ≥30 and ≤40 kg/m2 ; approved for up to 6 months
- Intragastric fluid-filled and swallowable gas filled balloon
- TransPyloric shuttle
- Efficacy: 12–31% excess weight loss over 6 months
- Safety: Stomach blockage with uncomfortable fullness, vomiting, stomach ulcer, gastric hypertrophy
- Endoscopic Plication Devices
- Mechanism: Endoscopic suturing of the stomach reduces gastric volume
- Indication: Investigational
- Efficacy: 30–50% excess weight loss for up to 1–2 years
- Safety: Stitch failure with weight regain
|Alkaline reflux gastritis||✓|
|Anemia (often related to mineral and nutrition deficiencies)||✓||✓||✓|
|B12 & B1 deficiency||✓|
|Band slippage, erosion, ulceration, port infection, disconnection, and displacement||✓|
|Dumping syndrome and reactive hypoglycemia||✓||✓|
|Kidney stones (oxalosis)||✓||✓||✓|
|Neuropathies (resulting from nutritional deficiencies)||✓||✓b|
|Osteoporosis (often caused by calcium deficiency and chronically elevated parathyroid hormone levels)||✓||✓|
|Other nutritional and mineral deficiencies (i.e., deficiencies of vitamins A, C, D, E, B, and K, folate, zinc, magnesium, thiamine)||✓||✓b|
|Potential need for removal, revision or conversion to another procedure||✓||✓||✓||✓|
|Rare nutrient deficiencies if persistent vomiting or marked and sustained decrease in nutritional intake||✓|
|Small bowel obstruction caused by internal hernias or adhesions||✓||✓|
|No weight loss||✓||✓|
|Worsening GERD or de novo GERD||✓|
b The BPD/DS has a much higher incidence of both macro- and micronutrient deficiencies compared to other bariatric surgeries.