-Gastric bypass is a bariatric surgery design to produce a weight loss will all the associate benefits. This surgery consist in creation of a small gastric pouch and a bypass of one part of the bowel for the food absorption.

-The food pass directly from the stomach to the intestine (alimentary loop) and are only absorbed more distally, when they are mixed with biliopancreatic secretions at the level of the common loop.

-The gastric pouch, constituting the “restrictive” part of the operation is small (volume of 15-20 ml) to induce early satiety and reduce the risk of anastomotic ulcers.

-The remaining stomach even if food no longer passes through its lumen, but will preserve the physiological function.

-This intervention is reversible.

-The modes of weight loss are complex and multiple:

1 / Restrictive effect: the small volume of the gastric pouch (15-20 cc) is accompanied by early satiety.

2 / Malabsorptive effect: This assembly leads to malabsorption which mainly concerns fats because they can only be absorbed in the presence of bile salts. Protein malabsorption is less because proteins are still partially absorbed by saliva and intestinal juices all along the digestive loop. Carbohydrates can be absorbed through the food loop and their intake in large quantities is one of the causes of failure during a gastric bypass.

Postoperative attitude:

• Day0 – The patient will be fasting.

• Day1- The patient is allowed to drink water (small amounts, spaced out during the day). The patient is also advised to mobilize, the first mobilization will be carried out with an accompanying person (nurse or physiotherapist) to avoid vagal mechanisms (eventually a temporary loss of consciousness with a subsequent fall).

• Day2- A control blood test is carried out and if the result is within the physiological limits and the patient is in a good general status, the discharge is authorized.

– The dietetician will see the patient before leaving hospital to explain the regime


– Anastomotic leak- related to problems of healing on the anastomosis with a peritoneal spillage of the digestive content

– Hemorrhages- related to vascular injuries

– Internal hernia- related to the passage of the small bowel through the mesenteric or Petersen space (this are spaces between the digestive structures created by the surgical configuration of the loops)