Bariatric Surgery

Listed below is the step by step procedure of bariatric surgery:

  1. What is Bariatric Surgery?
  2. Why is Bariatric Surgery Required?
  3. Pre-operative Preparation
  4. Day Before Surgery
  5. Procedure Day
  6. Methods/Techniques of Bariatric Surgery
  7. Post Procedure
  8. Risks and Complications

What is Bariatric Surgery?

All the surgical procedures, which aid in weight loss by altering the digestive system suitably , are included in bariatric surgery. The stomach and lower intestines are restructured in such a way that the quantity of food which a person can consume is lessened. This also leads to reduced absorption of nutrients. Both these help in stimulating weight loss. Bariatric surgeries, eventually change the person's appetite.

what is bariatric surgery?

They may also alter the digestive functions in such a way that the person does not feel hungry between two meals. All these weight loss surgeries are collectively termed as bariatric surgery.

Why is Bariatric Surgery Required?

Bariatric surgery is indicated in obese people. The term 'obese' does not apply to everyone who is overweight. Obesity is a medical term and by definition is applicable to people whose BMI (Body Mass Index) is more than normal. BMI is the ratio of body weight and height. Obesity is graded depending upon the patient's BMI. It is treatable with exercise and methods. At times however, surgery is indicated as the only choice of treatment. A few indications of bariatric surgery are mentioned below:

    High B.M.I

    As explained above, obesity is diagnosed based on the BMI. A BMI ranging between 19-25 is considered healthy. People having BMI above 25 fall in the overweight category. Obesity can be diagnosed in people who have BMI above 35. Obese people having BMI of 40 and above are likely candidates for bariatric surgery.

    Health Conditions Due to Obesity

    Obese people are likely to be victims of diseases like diabetes, cardiac problems, hypertension. If weight loss does not occur in such patients, the other health conditions might progressively worse. Bariatric surgery might be advised to these patients.

    Low B.M.I with Associated Health Conditions

    Patients who do not have B.M.I. As high as 40, but who suffer from health conditions because of obesity are likely to be advised bariatric surgery. Sleep disorders, diabetes, high cholesterol are some of these conditions.

    Failure of other weight loss Methods

    Obese patients can try exercise, medicines, herbal products, massage to try and lose weight. Sometimes these methods help the patient to achieve the desired weight loss. But in cases where no amount of effort helps weight loss, bariatric surgery remains the only treatment option.

Before qualifying for bariatric surgery the patient undergoes extensive medical examination and investigations. If all these are within the required limits and any one of the above indications is noticed in the patient, only then they are chosen to undergo bariatric surgery.

Pre-operative Preparations

Bariatric surgery is different from other surgeries. It needs more extensive preparation which may begin as early as a month or two before the actual date of operation. The patient and doctor have to work together to achieve all pre-operative goals. The success of surgery depends to quite an extent on this. Some important pre-operative steps steps have been mentioned below:


    Obese patients are often victims of conditions like diabetes, hypertension, metabolic syndrome, heart diseases. They may be on medicines for the same. The surgeon who is operating upon the patient will review the medicines properly. Their dose may be altered as the surgeon sees fit. Some medications might be stopped as well.

    Lifestyle Changes

    Patients should not rely on the surgery and give up on their attempts to lose weight. They should increase their efforts and lose as much weight as they can. Enrollment in a gymnasium for an weight loss program under supervision of fitness trainers is advised to patients. Other forms of exercise like walk, yoga, aerobics might be helpful in some cases. Patients who are regular consumers of alcohol and tobacco will benefit a lot if they abstain from these habits.

    Food Habits

    Quite a few restrictions are imposed on the patient since a month before surgery. Junk food, sugar rich food, food high on calorie content is strictly prohibited. Salads, fruits, natural food items free from preservatives are encouraged to be consumed.


    Candidates of bariatric surgery are required to undergo a battery of blood tests and other investigative tests before the surgery. Blood tests to determine sugar levels, cholesterol levels, thyroid, kidney and liver function are performed. If they are not within normal limits, they have to be normalized prior to surgery.

    White blood cell count is done just before surgery to ensure there is no underlying infection. Surgery cannot be performed in case of active infection.

    Most of the bariatric surgeries involve reshaping and realigning the digestive tract, hence prior to the surgery a sonography is performed to assess the intestinal tract. Gallstones might be diagnosed as they develop commonly in overweight and obese people.

    ECG is done to determine cardiac functions. X-Ray of the chest helps to visualize the shape and size of heart and lungs. Lung function tests might be additionally performed. A treadmill test (stress test) may be done sometimes in patients who are able to perform physical activities like running.

    Physical Examination and Patient Evaluation

    Prior to the surgery, a complete physical examination is done. Pulse, blood pressure, body temperature and breathing rate (vitals) are measured. The patient's height is measured. Weight has to be measured recurrently to map the changes in B.M.I. As the weight changes, the B.M.I changes correspondingly.

    Examination of the cardiovascular system is done to detect signs of abnormal cardiac functions. A dietician will evaluate the patient's nutritional status and past attempts to follow diet. Certain health conditions are a deterring factor for proceeding with bariatric surgery. These include kidney stone, gall stone, bleeding disorders. If they are detected, they have to be treated prior to the surgery.

    A psychological evaluation may be advised in cases where some underlying mental disorder is suspected. Conditions like depression , anxiety, eating disorders could contribute to development of obesity. In such cases, psychological counseling will be needed along with other treatment methods.

    Method of Surgery

    Bariatric surgery is not one single surgery, but several operative methods which help in stimulating weight loss. Each case of obesity is different and may require any of these methods. Depending on the examination findings, results of the investigations, general health and age of the patient, the method of surgery is chosen.

Day before Surgery

It is generally advisable to get admitted to the hospital a day prior to surgery. A thorough physical examination is done again after the patient is admitted. Vitals are monitored at set time interval. The patient's weight is checked once before surgery.

Bariatric surgery involves restructuring the position and shape of stomach or small intestine. Therefore it is necessary for the patient to keep an empty stomach since one night before the surgery. It is difficult to operate upon a full stomach or intestine. Surgery is performed under general anesthesia. This also requires the patient to have an empty digestive tract. Antacids and laxatives might be prescribed for the same. Patient is advised to relax physically and to avoid mental stress.

Procedure Day

On the day of surgery, well before the decided time of the procedure, the patient is taken to the operation theater. All the surgical equipment and clothing which will be used are treated before hand to get rid of all microorganisms. A clean surgical gown is worn by the patient during surgery. A pre-opertive dose of heparin (anti-blood clotting agent) may be administered.

After monitoring the blood pressure once again, anesthesia is administered to the patient. It can be done in the form of an injection given into a vein in the arm or in the form of respiratory fumes. The skin over abdomen is shaved off any hair and cleaned with an antiseptic solution. Only when the anesthetist confirms that the patient is completely under effect of anesthetic agent, surgery can be started.

Methods/Techniques of Bariatric Surgery

Bariatric surgery methods involve operating up on the digestive tract. Some of the most commonly employed techniques have been mentioned below:

    Gastric Banding

    As the name suggests, a band is tied around the stomach. The procedure can be done laparoscopically. Multiple small incisions are given over the abdominal skin over the stomach. Surgical equipment is introduced into the abdomen through these incisions. Underlying abdominal muscles, fascia and fat are dissected. Care is taken to avoid injury to adjoining healthy organs. An adjustable band is tired around the stomach between the upper and lower part. This will narrow stomach.

    The long term effect of this surgery is that the quantity of food consumed at a time reduces, thus stimulating weight loss. The abdominal muscle which were dissected are replaced to their former position. Surgical incisions are closed with a medically designed thread.

    gastric banding

    The band tied around stomach is made of silicone. A tube connects the silicone band to a device placed under the skin. Through this tube, saline can be injected into or removed from the band to adjust its tightness.

    A variant of this surgery is vertical banding gastroplasty. After a band is placed around the stomach, the surgeon will make a small pouch of the stomach and staple it. This further reduces food intake. But the surgery does not promote as much weight loss as other surgeries and also has more complications. Hence it is utilized less commonly.

    Sleeve Gastrectomy

    Gastrectomy means removal of stomach. Sleeve gastrectomy involves removal of a part of the stomach from one side. The surgery is done by laparoscopic method. Through multiple small incisions on the abdominal skin, surgical instruments are inserted inside the abdominal cavity. A video camera (laparoscope) is introduced to record and visualize the internal organs. This gives more precision while performing the surgery.

    Sleeve Gastrectomy

    The left side of stomach is surgically cut and removed in this process. This leaves behind a vertical tube like structure. It is is sealed together with staples. Because the size of stomach reduces drastically after this surgery, intake of food is restricted which promotes weight loss.

    Gastric Bypass

    The term bypass means avoiding one path and finding an alternate route to proceed. In gastric bypass surgery, the food is allowed to remain in the stomach for a very little time and directly pass into the intestine. The procedure can be done laparoscopically or with open method. Through incision, surgical tools are passed inside the abdominal cavity.

    If laparoscopic method is being used, multiple small surgical incisions are made on the abdominal skin. If open surgery is being done, a single larger incision will be made. Laparoscopy involves using a video camera atatched to a long flexible tube being introduced inside the abdominal cavity. This helps to get an idea about the structure of the internal organs.

    Gastric Bypass

    The further procedure is same for both methods. The stomach is divided and the upper part is tied up like a pouch. The remaining lower part of the stomach, which is the larger portion is then either surgically removed, or bypassed. The initial part of the lower intestine is directly connected to the upper small pouch of the stomach. Due to the reduced volume of stomach cavity, very little food can be consumed at a time. The food passes almost immediately to the intestines, thus reducing the digesting time. This leads to lesser absorption of calories and unwanted fats. Thus weight loss can be achieved faster.

    Duodenal Switch

    The surgery can be done with open or laparoscopic method. In open method, a single large surgical cut is made over the abdominal skin. For laparoscopic method, multiple smaller incisions are made. Through one of the multiple incisions, a laparoscope is inserted. This is a camera which records and allows the operating surgeon to see the internal organs. This facilitates the surgeon to have a clear field of vision during surgery. Rest of the steps are same for both the approaches.

    A large part of the stomach is removed. The lower opening of the stomach known as pylorus, is directly connected to the lower portion of small intestines. This way, food does not pass through the intermediate portion of small intestine. Digestion time of the food is reduced and there is reduced absorption of calories and fats. This will accelerate weight loss and help in reducing excess body fat.

    Duodenal Switch

    The portion of the intestines which is bypassed continues to receive bile and liver enzymes needed for digestion. They are passed on the the lower part of the intestine. A segment of small intestine serves as a common pathway for both these paths, i.e., the one which receives bile and the one where pylorus is connected to the small intestine. In this common pathway food and bile mix and further digestion takes place. It is a complicated procedure.

Any one of these surgeries or a combination of them may be performed in an obese patient. A lot of post-operative care and restrictions are associated with bariatric surgery. The long term success of bariatric surgery depends a lot on how well these restrictions are followed.

Post Procedure

Immediately after the surgery patient is taken to the recovery room. Consciousness is regained soon after the effects of anesthetic agent reduce. The patient is examined thoroughly. Vitals are continued to be monitored. Hospital stay for about 2-3 days is necessary during which the patient is kept under observation. They may be discharged sooner or after this duration depending upon their recovery. Complete recovery form surgery takes about 3-4 weeks. After bariatric surgery, efforts have to be put in by the patient as well as doctor to achieve the desired weight loss and to maintain it. Some useful information for post-operative care are mentioned below:

    Weight Loss

    A general misconception is that the patient will have lost a lot of weight immediately after surgery. This is not true. Bariatric surgery does not remove any excess fat or weight from the person's body, it merely paves the way to stimulate weight loss. A regular exercise regimen is advised to the patient which has to be followed strictly. If adequate weight loss is not done properly, the surgery will not produce much benefit. Weight loss can be achieved by exercise like brisk walk, yoga. Once the person loses some weight and gets more mobility, they can proceed to aerobics, jogging, going to the gym. Massage therapy also helps in weight loss. Once the desired weight is achieved, exercise has to be continued to maintain it.


    Immediately after surgery, patient is not allowed to consumed food for 1-2 days. The nutritional requirements are maintained via intravenous route. For the next 3-4 months, a special diet is advised by the nutritionist. It includes soft, light food which is easy to digest. Food intake reduces drastically after bariatric surgery. This is because the area of stomach available for accumulating food is very less. Patients observe a change in their appetite. They cannot eat large quantities of food at a time. It is advisable to eat small meals at regular intervals for such patients. The surgery can lead to malnutrition as absorption of essential nutrients is affected. Hence, it is advised to have balanced meals to fulfill as much of the nutritional requirements as possible. Consumption of adequate water is advised to patients to maintain hydration levels.

    Lifestyle Changes

    After surgery, the patient may have to follow certain restrictions for life long to achieve and maintain the desired weight loss. One of these is to ration the quantity of food consumed at each meal. Regular physical activity is also essential to avoid gaining weight again. Both these have been explained above in detail. Smoking and alcohol consumption are to be avoided as much as possible for life long. They may cause undesirable weight changes.


    Regular follow ups with the bariatric surgeon are advised to the patient. These may be done once or twice in a month. During follow up the patient's weight and B.M.I are checked. This will give the doctor and patient both, an idea about the progress being made. During follow up, the patient's medicines can also be reviewed and necessary changes can be made. If the patient has had any health conditions associated with obesity prior to surgery, medicines for the same are continued after surgery. Once weight loss begins, these conditions may resolve and dose of medicine can be altered accordingly. Diabetes, high cholesterol levels, high blood pressure, may be some of these conditions.

    Psychological Counseling

    As mentioned earlier in this article, psychological stress, depression, anxiety are some of the causes of obesity. In such patients, psychological counseling plays as important a role as bariatric surgery. Discussion and therapy sessions with a psychologist at regular intervals will benefit the patient greatly. In some cases, where the cause is too deep rooted, psychiatric medication may be needed.

Restrictions related to diet and exercise have to be followed for life long after surgery. The patient will be evaluated periodically. The frequency of evaluations reduces as times passes. There are some drawbacks associated with weight loss surgery. These could occur during the surgery, during recovery period or later.

Risks and Complications

Bleeding and Blood Clot Formation

Bleeding is more likely to occur during open surgery than laparoscopy. Blood obstructs the field of vision during surgery and needs to be drained. If blood clots are formed, they have to removed mechanically. Smaller clots may however enter some vein and could cause health complications if they block the vein. Blood thinning medicines will be administered in such cases.


Infection can occur at the site of surgical incision or in some cases internally, upon the parts which were operated. It may be presented in the form of swelling, redness and pain a the site of incision. If internal infection is present, fever and abdominal pain may be present. Antibiotics help to control the infection.

Digestive Troubles

After bariatric surgery there is a lot of change in the normal digestion. Food does not pass through the normal route through intestines. The time of digestive process is also altered. This could lead to affected absorption of essential nutrients. Problems like malnutrition, constipation, nausea vomiting could arise. Altering the diet, quantity of food consumed at a time and time interval between two consecutive meals may help to curb these complaints. Gallstones are known to occur in people who lose a lot of weight in a relatively short time span. If they are diagnosed in a patient after bariatric surgery, appropriate treatment in the form of medicines or corrective surgery is provided separately for them.

Bariatric surgery can give a very good outcome if all the instructions are followed carefully. Life long care is needed for patients after this surgery. Before undergoing the procedure it is advisable for patients to get complete information about the pre-surgical requirements, surgical methods and post-operative care. The outcome may not be exactly the same for each patient undergoing bariatric surgery, but the end result is that the patient ends up loosing quite a lot of their unhealthy weight.

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