Some obese people, for various reasons, are unable to get rid of their excess weight through dietary changes, increased physical activity or medication. Obesity surgery is often the only solution in such cases. In the 70 years that this field of medicine has existed, new methods of surgical treatment of obesity have been continuously developed, improved to be safer, more effective and less invasive. Some of them are rarely used, as more data on adverse effects has become available, and there is a wide variety of gastric reduction surgeries to replace the.

Operations can be of two types or combined

More than 10 different obesity reduction surgeries are currently recognised worldwide. All of them are minimally invasive, either laparoscopic (through small holes in the abdominal wall) or endoscopic (through the mouth, from the inside). Patients often find it difficult to objectively evaluate the surgical options available for obesity treatment on their own due to a lack of information and myths.

Prof. Antanas Mickevičius, a renowned obesity surgeon in Lithuania and abroad with more than 15 years of experience in the field of obesity surgery, advises on how to choose the most suitable one, what to take into account and how to avoid mistakes. He performs most of the world’s most renowned gastric reduction surgeries and applies other less interventional methods of obesity treatment.

“The two most popular and most frequently performed operations in recent years, both in other countries and in Lithuania, are gastric reduction – gastric sleeve and gastric bypass. However, as in every field of surgery, new and more effective options are always being sought in obesity surgery. Some catch on, some don’t,” comments Prof. A. Mickevičius, MD.

He points out that in a gastric sleeve operation, the surgeon forms a new stomach that is 70-80% smaller and the food travels along the normal path, whereas in a gastric bypass operation, the stomach is not only formed into a new, smaller stomach, but it is also disconnected from the larger stomach, and a bypass is created, which allows the remaining part of the stomach and a part of the small intestine to be bypassed and thus significantly shortens the food’s passage along the intestines.

Prof. A. Mickevičius, MD, PhD, points out that there are two main types of gastric banding surgery – restrictive and malabsorptive. Restrictive surgery focuses on reducing the volume of the stomach so that a person cannot eat much food. This type includes the formerly widely used gastric ring operation and now increasingly being replaced by subtotal gastric sleeves.

Malabsorptive surgery maintains a larger stomach volume than restrictive surgery, but reduces the absorption of nutrients in the gastrointestinal tract and thus the amount of calories available. This is achieved by more or less shortening the path of food passage through the intestine. This type includes duodenal bypass surgery.

Both classic gastric bypass surgery and the other most widely used gastric bypass surgeries are combined operations, with both a restrictive and a malabsorptive component.

Prof. A. Mickevičius, MD, PhD, gives an overview of the most common gastric bypass surgeries currently used in other countries, highlighting their differences, similarities, advantages and disadvantages.

SADI-S surgery: recommended for the extremely obese

SADI-S surgery, which has a restrictive and malabsorptive component, consists of a classic subtotal gastric resection, only slightly wider, followed by a 70-75% smaller stomach. The incision of the duodenum at the upper part of the duodenum creates a new connection between the duodenum and the middle part of the small bowel. The total length of the small intestinal canal after this operation is between 2.5 and 3 m, which means that it is shortened by a third or half, and the food passageway is shortened.

The effect is twofold: the person eats less and absorbs fewer nutrients. The advantage of this operation over a traditional gastric bypass is that only one connection is formed, between the duodenum and the ileum, instead of two. This slightly reduces the risk of joint failure, scarring and bleeding from the joint. Another advantage is the slightly higher weight loss observed.

SADI-S surgery is recommended and is more often performed on people who are very overweight and have type 2 diabetes, which is very well corrected, with blood sugar levels regulated, no need for medication, and improved quality of life. It also improves the condition of obese patients with polycystic ovary syndrome and hypercholesterolaemia.

However, it should be noted that deficiencies of vitamins, especially fat-soluble vitamins A, D, E and K, are more common after this operation, as a large part of the small intestine is no longer involved in digestion. Protein deficiency can also occur occasionally if a person does not consume enough of it. Also, as the length of the intestine is reduced, patients have slightly more frequent bowel movements.

SADI-S obesity reduction surgery has become more widespread in other countries in the last five years, even though the technique was developed more than 15 years ago. In Lithuania, these operations are performed on extremely obese people who need to lose a lot of weight, and there are not very many of them, so it is not a common choice.

SASI-S surgery: reducing the risk of becoming overweight again

SASI-S surgery is similar to SADI-S and is also combined. The main difference is that the gastric sleeve resection (reduction of the stomach) forms a connection between the stomach and the small intestine. The duodenum is not disconnected, leaving a natural food flow path. However, another connection is formed about 2.5 m from the end of the small intestine. In this way, the food follows two paths, the normal one and the additional connection directly to the back of the small intestine.

The advantage of this operation is that some of the food travels by a shorter route, which reduces the absorption of nutrients and thus calories, but leaves the natural route. If necessary, it allows the duodenum to be examined endoscopically. In addition, the new connection between the stomach and the small intestine means that the stomach is less likely to be distended and the patient is less likely to regain weight after a certain period of time, as the pressure on the lower gastric valve is reduced.

This surgery has been performed in the last decade, with good near-term results. However, it has its drawbacks: the formation of a connection between the stomach and the small intestine can lead to reflux of bile up into the stomach or oesophagus, which increases the risk of ulcers, especially in smokers. The outcome of this surgery is unknown.

Mini gastric bypass: simpler technique, fast performance

Mini gastric bypass is another type of obesity reduction surgery. Like the classic gastric bypass, it involves forming a smaller, narrow tube-shaped stomach, which is disconnected from the large stomach and connected to the small intestine, bypassing about 2 metres of it. The main difference is that in a mini gastric bypass, only one connection is formed, not in the shape of a Y, but in the shape of an omega and in a different location.

The effect is the same as a classic gastric bypass: the new small stomach can only hold a small amount of food, so you feel fuller faster and eat less. At the same time, the food pathway in the digestive system is shortened, resulting in less absorption of nutrients and calories. As a result, weight loss is faster.

The advantages of the mini gastric bypass are that, as there is only one connection, the operation is slightly faster. It is equivalent and even superior to the classic gastric bypass in terms of weight loss, type 2 diabetes, high blood pressure and correction of polycystic ovary syndrome.

The weakness of this operation is that the shape of the omega junction means that the bile travels through it and does not have a separate pathway, as in the classic gastric bypass. As a result, the bile-containing contents of the small intestine can enter the newly formed stomach and cause inflammation and ulcer formation.

However, in some countries, the mini gastric bypass has recently become more popular than the classical gastric bypass due to its simpler technique and quicker performance, taking between 45 minutes and an hour.

Gastric plication: need for self-monitoring, increased risk of weight gain

Gastric plication is another surgical treatment for obesity. This surgery is of the restrictive type. It involves the formation of a narrow tube from the stomach, but without damaging the integrity of the stomach, simply by mechanically stitching the walls together to reduce the volume. With a smaller stomach, much less is eaten and a feeling of fullness is felt more quickly, and food passes through the intestines naturally.

The advantage of this surgery is that it is very minimally invasive, as it can be performed laparoscopically from the outside, through small holes, and orally from the inside, endoscopically, without forming connections. There are other advantages: post-operative complications are extremely rare and, if necessary, the gastric stitches can be dismantled and the stomach returned to its original state.

However, after gastric bypass surgery, you need to control yourself more – try not to overeat, as overeating can quickly lead to nausea and vomiting. Weight loss after this operation is slower than after gastric bypass or resection surgery.

Another disadvantage is that after 2-4 years, the body adapts and patients experience an increased sense of hunger. They may start to snack or increase portions. This can lead to burst stitches and, as the stomach grows larger, more food is eaten, which leads to weight gain.

Gastric ring surgery: more cons than pros, rarely performed

Gastric ring surgery is another type of surgery used to treat obesity. It involves dividing the stomach into two parts by putting an adjustable band around it. Food is first delivered only to the upper part of the stomach, as it is usually left with a capacity of 100 ml, the patient cannot eat much food. The band is connected to a special reservoir filled with saline fluid in the subcutaneous tissue. It can be tightened or loosened to regulate the amount of food flowing through.

The adjustable ring results in the least weight loss compared to other gastric reduction surgeries. The operation has a number of undesirable effects that become apparent over time: the ring can eventually cause the stomach wall to sag and slip. As it is a foreign body, it can become rusty, leak and lose its tightness. Sometimes there is a failure of the lower arm of the oesophagus, with symptoms of reflux, possibly even regurgitation of gastric contents into the airways, and pneumonia.

This operation had its golden age 15-20 years ago, when there were not so many alternative more innovative, safer and more effective gastric reduction operations, and it is now relatively rarely performed worldwide. The other most popular surgeries for obesity are also far superior in terms of improving the quality of life after surgery.