Welcome Collapse
Bariatric Surgery Collapse
Nutrition Collapse
QA Collapse
Article of the month Collapse


Bariatric Surgery


Complexity of Laparoscopic Procedures

The recommendation is that these complex procedures should only be attempted by an experienced center when they have performed at least 150 GBP cases when morbidity and mortality can be expected to be low. (Mortality Rates Figure)

Bariatric/Metabolic Surgery – 30 Day Mortality Rates

There are three types of Bariatric/Metabolic surgery for weight loss:

  • Restrictive procedures limit intake and contain no intestinal bypass. These types would include gastric banding and sleeve gastrectomy
  • Procedures altering gastro-intesinal peptides with gastric restriction: Roux-en-Y
  • Malabsorptive procedures involve bypassing a portion of the intestine e.g. Scopionaro and Biliopancreatic diversion with duodenal switch (BPD-DS)

Gastric bypass surgery will induce weight loss by one of three mechanisms:

  1. Restriction of volume
  2. 120 – 150cm of the gastric outlet is bypassed, resulting in minor calorie wasting

Induction of satiety by altering the gut peptides PYY, GLP

Malabsorptive procedures

While restrictive procedures limit the amount of food, malabsorptive procedures limit the amount of energy absorbed from the foods ingested by bypassing some portion of the intestine.

Most malabsorptive procedures combine an intestinal bypass with a restrictive procedure. This method of restricting intake and absorption together has proven to be the most effective method of assuring long-term weight loss.

Sleeve Gastrectomy

Data on the efficacy and safety of SG as a staged or primary procedure are just now being collected. A few short-term series with more than 100 patients have been conducted, but findings are insufficient to conclude that the approach offers greater perioperative safety than any other WLS procedure.

However, collective retrospective data suggest that it is at least as safe as RYGB, with an overall complication rate of approximately 24% and a mortality rate of 0.37%. Evidence suggests that SG is as effective as RYGB at treating obesity and its comorbidities.

Like malabsorptive procedures, SG produces a marked and sustained reduction in ghrelin levels up to a year after the procedure; an outcome that may reduce desire for food.


Roux-en-Y bypass

The Roux-en-Y is currently the most extensively performed bariatric procedure. It can be accomplished either open or laparoscopically, the preferred method being laparoscopic. This operation is the most common of malabsorptive and restrictive surgical procedures. In the Roux-en-Y, a small stomach pouch is created to restrict food intake.

The intestine is severed, the lower section of the small intestine is attached to the pouch to allow food to bypass the remaining stomach, duodenum (the first segment of the small intestine), and the first portion of the jejunum (the second segment of the small intestine). Roux-en-Y’s are done either proximal (with a shorter length of the intestines bypassed), or distal (with more of the intestines bypassed).


Biliopancreatic Diversion (BPD/DS)

The BPD/DS is a primarily malabsorptive procedure. It involves a long, narrow sleeve gastrectomy, preserving the antrum and pyloric sphincter.

The duodenum is transected above the ampulla of Vater and the ileum is transected 250cm proximal to the ileocecal valve. The distal end of the transected ileum is anastomosed to the proximal end of the transected duodenum.

The proximal end of the transected ileum is then anastomosed to the distal ileum, 100cm from the ileocecal valve. With this operation, the common channel is usually only the distal 100cm of ileum.

The BPD/DS is associated with a mean loss of 85% of excess weight and with mortality of about 1.0%. The operation is associated with fat malabsorption and may cause protein-calorie malnutrition deficiencies in fat-soluble vitamins, iron and calcium, as well as foul-smelling stools associated with the steatorrhea.


BPD-SIPS (Stomach Intestinal Pylorus Sparing)


Weight changes, operative mortality, morbidity and long term mortality outcome

Mean % patients with complete resolution of comorbidities post-operative
Major Comorbidity Operations
Gastric Bypass Biliopancreatic Diversion
Diabetes 84 99
Dyslipidaemia 97 99
Hypertension 68 83
Sleep apnoea 80 92


  • Patients without any clinical or psychological contra-indications
  • Patients at a BMI above 40
  • Patients at a BMI above 35 with co-morbid diseases where conventional treatment has failed
  • Patients at a BMI >30 with poorly controlled diabetes mellitus