Roux-en-Y gastric bypass is a restrictive, malabsorptive approach for weight loss. The patient’s food intake is restricted, and an extremely small gastric pouch (30 ml) ensures early satiety. Ingested food goes through the remainder of the stomach without going through the duodenum and the proximal region of the jejunum due to this anastomosis between the gastric pouch and the distal jejunum, which hinders digestion and absorption. Recent research has demonstrated that the hormonal changes that follow RYGB are also helpful for weight loss. Following a Roux-en-Y gastric bypass operation, levels of glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) increase, whereas leptin and ghrelin considerably drop. Patients experience less hunger as a result of these alterations, as well as a greater sense of fullness. The limiting aspect of this surgery is thought to have contributed to 50–75% of the patient’s weight loss following RYGB, with about 5% of it being brought on by reduced nutrient absorption. The remaining 20–45% is thought to result from hormonal changes brought on by RYGB.

Type 2 diabetes can be cured or reversed with Roux-en-Y gastric bypass. Shortly after RYGB, but before weight reduction starts, patient’s blood glucose levels drop and their requirement for insulin declines. The RYGB’s anti-diabetic impact is complex. The endocrine changes that come from calorie restriction and weight loss also contribute to the antidiabetic effects of RYGB. Following RYGB, blood glucose levels decrease concurrently with a decrease in both the amount of circulating insulin and insulin-like growth factor-1 (IGF-1). Incretins are gastrointestinal hormones that compel the beta cells in the pancreas to release insulin. Incretins include glucagon-like peptide-1 and gastric inhibitory peptide (GIP), and plasma levels of these hormones significantly rise with RYGB.

During the first stage of the procedure, a tiny gastric pouch is created, with an interior capacity no more than 30 ml. Remove adipose tissue, expose the left side of the esophagogastric junction (His angle), and the first 4-5 cm of the great curve. Then, ligate the short gastric artery (if present). On the smaller curvature side, a hole is formed in the hepatogastric ligament 2-4 cm away from the esophagogastric junction, and the lesser omentum is put into the stomach’s posterior surface. These regions, which were created on the left and right, eliminate the typically nonvascular tissue beneath the stomach and make room for the surgical staples to operate. The amount of acid-secreting gastric mucosa within the pouch is kept to a minimum because the pouch that forms must not enclose the fundus. The proximal stomach can be made with a single horizontal incision and TA-90B staples. This stapler’s straight anvil is advanced by slipping it through the minor curve hole and removing it from the major curve. The front of the stomach has a bigger area than the back when the clamp handle is pulled down, which enables the punch to close and strike.

Just below the first punchline, make a second shot using a second TA90B. The proximal follicle is severed from the remainder of the stomach at the point where the two staple lines meet. The creation of Roux-en-Y occurs in the second step of operation. At the Treitz ligament, the proximal jejunum is removed 50–70 cm behind her. The created gastric pouch is anastomosed with the distal portion. The Lu arm, vegetative arm, or efferent arm are all names for this component. The proximal part is known as the afferent arm or biliary pancreatic arm. A hole should be made in the gastrocolic web.An anastomosis is made between the Roux arm and the front surface of the proximal gastric pouch during the third stage of surgery. For this, a circular punch with a 21 mm diameter is employed. The proximal gastric pouch has a 1 cm anterior surface. A circular stapler anvil is put into the length. The tissue surrounding the anvil rod is pushed together, and a pouch opening is stitched around the hole. The roux arm’s incision is 5–10 cm away from a circular staple that is put through the incision. The jejunal wall is opened, and it is then clamped with an anvil rod. Compress the two tissues, then rotate the stapler to bring the jejunum closer to the incus. Consequently, a cardiojejunostomy is made. The Roux arm (efferent arm, afferent arm) and the afferent arm (biliary pancreatic arm) are anastomosed at the fourth stage of the procedure. 150 cm distal to the cardiac jejunal fistula, a jejunal fistula is made.

• Complications during surgery,
• Early problems after surgery,
• Prolonged difficulties

According to reports, RYGB has a 16% overall complication rate and a 0.4% mortality rate.

The most frequent reason for death after a Roux-en-Y gastric bypass (accounting for about 50% of deaths) is pulmonary thromboembolism. Myocardial infarction is the second most prevalent cause of mortality. Leakage and respiratory failure follow this cause. The RYGB complication that causes intestinal leaking is the most terrifying problem. The majority of leaks occur in the first 7 days, and the other in the first 28 days. Leakage can result in a 30% increase in mortality risk. Leakage also increases the risk of bleeding, wound infection, gastrocolic fistula, and respiratory failure.

Following a Roux-en-Y gastric bypass, protein, iron, calcium, vitamin B12, and vitamin D deficiencies are the most common nutritional problems. In 20–49% of patients, anaemia due to iron deficiency is observed. Multivitamin preparations do not provide enough iron to completely cure iron insufficiency. If iron deficiency anaemia is diagnosed, it should be treated with iron sulphate 600–1000 mg/day. Between 26 and 70 percent of individuals have vitamin B12 insufficiency. Patients should receive vitamin B12 supplements even if clinically symptomatic vitamin B12 insufficiency is uncommon. A daily intake of 350 micrograms cures deficiencies. Roux-en-Y Gastric Bypass related calcium and vitamin D deficiencies can be cured by taking supplements of 1500 mg/day of elemental calcium and 400 IU of vitamin D per day.