Gastric bypass is considered the gold standard of bariatric surgery. Bariatric surgery is usually recommended for patients with a Body Mass Index (BMI) higher than 40, or a BMI of 35 and an associated disease, such as high blood pressure, heart disease, diabetes, metabolic disease or sleep apnea, and it works by reducing the size of the stomach and / or redirecting the course of the digestive system.

In the case of the gastric bypass, surgeons start by dividing the top of the stomach and creating a small stomach pouch with surgical staples. Next, the small pouch is connected to the last part of the small intestine, creating a bypass. After the surgery, patients feel full faster and with smaller amounts of food due to the reduction in the stomach’s size, while food does not pass through part of the stomach and small intestine, which means that there is a decrease in caloric absorption. Treatment with bariatric surgery does not start or end with the procedure, so patients may benefit from being aware of the gastric bypass journey ahead.

Prior to Gastric Bypass Surgery

Even before deciding on gastric bypass, there are many steps for patients to take. Patients are evaluated by a medical team that analyzes overall health, need for bariatric surgery and eligibility criteria, while patients should inform themselves about implications like the risks associated with the treatment, potential results and the commitment needed both before and after the gastric bypass. Serious lifestyle alterations are required even prior to the surgery, which include adopting a healthy diet and regular exercise — changes that are recommended to be followed for the rest of patients’ lives.

There is no fixed plan, but each patient is followed by a series of specialized physicians, who will together define a plan months before the gastric bypass. In addition to the dietary restrictions and substitution of fats and sugars by healthy meals, patients are also recommended to plan their meals to ensure proper food choices, as well as drink at least 64 ounces of water daily, avoid alcohol, and take a multivitamin, mineral and calcium supplements.

In addition to considering all aspects related to the surgery and starting to make behavioral changes, before the surgery, patients also need to take into consideration the costs of the journey and seek insurance coverage or payment plans. Days before the gastric bypass procedure, the medical team provides specific instructions on the preparation for the day, conducts lab tests and exams, prescribes the medication taken by the patients, and asks patients to quit smoking. Patients may also need to plan their recovery, home and work arrangements, and ask for the help of family or friends during the first days.

Gastric Bypass Surgical Procedure

The night before gastric bypass, patients can’t eat or drink anything, since an empty stomach minimizes surgical risks. Similarly, it is also important to ask a friend or family member to be there the day of the surgery to offer comfort and support. During the day, patients are put asleep under general anesthesia for the gastric bypass. The procedure can be performed either as open surgery or laparoscopically, but it is currently much more commonly performed as laparoscopic gastric bypass, since it is a less invasive procedure. The surgeon makes small incisions in the abdomen to insert the surgical instruments and a small camera called a laparoscope.

The small stomach pouch created in the first step of the surgery is approximately one ounce or 30 milliliters in volume, and it is completed by dividing the top of the stomach from the rest of the stomach. The second step is to create the bypass itself and surgeons do so by dividing the first portion of the small intestine and bring up the bottom end of the divided small intestine to be attached to the newly created small stomach pouch. Finally, surgeons will end the procedure by connecting the top portion of the divided small intestine to the small intestine further down in order to enable the mixing of the food with the stomach acids and digestive enzymes from the bypassed stomach and first portion of small intestine.

“The gastric bypass works by several mechanisms. First, similar to most bariatric procedures, the newly created stomach pouch is considerably smaller and facilitates significantly smaller meals, which translates into less calories consumed. Additionally, because there is less digestion of food by the smaller stomach pouch, and there is a segment of small intestine that would normally absorb calories as well as nutrients that no longer has food going through it, there is probably to some degree less absorption of calories and nutrients. Most importantly, the rerouting of the food stream produces changes in gut hormones that promote satiety, suppress hunger, and reverse one of the primary mechanisms by which obesity induces type 2 diabetes,” explains the American Society for Metabolic and Bariatric Surgery (ASMBS).

Following Gastric Bypass Surgery

As patients wake up from the gastric bypass, they usually have a drip in their arm to provide liquids to the body, as well as a urinary catheter to drain urine from the bladder. Hospital stay is usually no longer than a day, but it may be prolonged to ensure that there were no complications to the surgery. The tubes will be removed when the patient becomes able to get out of bed, while physicians may prescribe blood-thinning medication and compression stockings to prevent blood clots. After being discharged from hospital, patients will start a liquid diet at home and gradually transition to solid foods in order to let the stomach heal and according to the doctor’s recommendations.

However, patients aren’t able to return to their normal activities three to five weeks after the gastric bypass. Patients will notice alterations in their normal digestive system and bowel movements, which is normal, but need to pay attention to side effects, including excessive bleeding, infection, adverse reactions to anesthesia, blood clots, lung or breathing problems or leaks in the gastrointestinal system, bowel obstruction, dumping syndrome that causes diarrhea, nausea or vomiting, gallstones, hernias, low blood sugar (hypoglycemia), malnutrition, stomach perforation, ulcers, or vomiting. Side effects are uncommon and death related to a gastric bypass is particularly rare, but it can occur.

In the case of complications, patients may need to be submitted to additional surgeries to correct the problem. After the surgery, patients will start regular follow-up medical visits, during which the recovery process is discussed. In addition, since the gastric bypass causes the food to bypass the part of the intestine where minerals and vitamins are absorbed, long-term vitamin or mineral deficiencies, particularly in vitamin B12, iron, calcium, and folate, are common and patients may need to take supplements. Studies reveal that gastric bypass produces significant long-term weight loss, with average 60 to 80% excess weight loss, and typical maintenance higher than 50%. Patients usually experience as well improvements in their overall health, comorbidities and quality of life.

Note: Obesity News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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