Roux-en-Y gastric bypass surgery

In many centers, laparoscopic Roux-en-Y gastric bypass has become the most common bariatric procedure for morbid obesity

In this operation, the stomach is stapled or divided to form a small pouch (typically <30 mL in volume), which empties into a Roux limb of the jejunum of varying length (typically 75-150 cm). 

The Roux limb may be brought up to the gastric pouch in two ways:

  • anterior to the transverse colon (antecolic-anterogastric)
  • posterior to the transverse colon (retrocolic-retrogastric)

There are two anastomoses: a proximal gastrojejunal anastomosis and a distal jejunojejunal anastomosis.

Although any visible defects that might allow potential bowel herniation are routinely closed at surgery 2, the antecolic approach has become preferred at some centers because a retrocolic approach requires bringing the Roux limb through the mesenteries and markedly increases the rate of an internal hernia.

Early complications of gastrointestinal complications of gastric bypass surgery include 3:

  • anastomotic narrowing/stenosis/stricture
    • most common cause of postoperative nausea and vomiting
    • may require lateral or steep oblique views to visualize
    • rare at jejunojejunal anastomosis (0.9%)
  • bezoar formation in the gastric pouch
  • ulceration
  • hemorrhage / hematoma
  • adhesionssmall-bowel obstruction
  • internal hernia  2
  • small bowel intussusception, retrograde much more often than antegrade 5-7

The Roux-en-Y is named after the Swiss surgeon César Roux (1857-1934), who was Chief of Surgery at the county hospital of Lausanne and following the opening of the new University of Lausanne, in 1890, was its inaugural Professor of External Pathology and Gynecology 4.

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Article information

rID: 14021
Section: Gamuts
Synonyms or Alternate Spellings:
  • Roux-en-Y procedure
  • Roux-en-Y gastric bypass

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Cases and figures

  • Figure 1: retrocolic-retrogastric roux limb
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  • Case 1: with Petersen`s hernia
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  • Figure 2: anterocolic-anterogastric roux limb
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  • Case 2: with anastomotic leak
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  • Case 3: Roux limb obstruction
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  • Case 3: Roux limb obstruction : CT
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  • Case 4: with internal hernia
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  • Case 5: Gastric remnant obstruction
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