Home Therapies Biliopancreatic Diversion: Process and Risks

Biliopancreatic Diversion: Process and Risks

by Josephine Andrews
Published: Last Updated on 416 views

The biliopancreatic diversion (also BPD or biliopancreatic division) is the most complex and at the same time most effective operation in obesity surgery. The procedure deliberately causes a disturbance in the absorption of food in the small intestine (malabsorption). However, biliopancreatic diversion cannot be completely reversed later and dietary supplements must be taken for life. Find out everything about the requirements, implementation and effects of biliopancreatic diversion here.

What is Biliopancreatic Diversion?

The term “biliopancreatic diversion” means that the digestive secretions from the bile (bilis) and pancreas (pancreas) are fed to the food pulp only in the lower part of the small intestine. As a result, the breakdown of nutrients is impeded and they are only absorbed into the blood from the small intestine in significantly smaller quantities.

Biliopancreatic diversion usually results in a particularly significant weight reduction in obese patients. Internationally, biliopancreatic division is considered the standard procedure, but it has hardly caught on in Germany.

What Happens Through Biliopancreatic Diversion?

The principle of action is primarily based on malabsorption caused intentionally by the operation – the technical term for poor absorption of nutrients from the intestine . Normally, the chyme from the stomach mixes with the digestive enzymes from the pancreas and gallbladder in the duodenum . The nutrients are thereby broken down and can now be absorbed by the intestinal mucosa and passed into the bloodstream.

Due to biliopancreatic diversion, however, they are only introduced much further down into the small intestine. Only from here do the food pulp and digestive juices mix. This means that only a short section of the intestine and significantly less time is available for the breakdown and absorption of food – a large part of the nutrients therefore migrates undigested into the large intestine and is excreted with the stool.  

However, the weight reduction does not only result from malabsorption alone. The second principle of action is the so-called restriction: During the biliopancreatic division, the stomach, among other things, is also significantly reduced. Due to the reduced stomach volume (restriction), you are full much faster and eat less.

Surgical procedure for biliopancreatic diversion

There are basically two variants of the operation: Biliopancreatic Diversion (BPD) alone and Biliopancreatic Diversion with Duodenal Switch (BPD-DS). In BPD, the stomach is reduced to a volume of around 250 to 500 milliliters. In BPD-DS, on the other hand, the stomach is reduced to a so-called sleeve stomach with a volume of only around 100 to 120 milliliters. The restriction in BPD-DS is thus even more pronounced than in BPD alone. Another advantage is that with BPD-DS the pylorus is preserved. The chyme therefore does not pass unhindered from the rest of the stomach into the intestines, but is released more slowly and continuously through the pylorus into the intestines.

Preparing for Biliopancreatic Diversion

Before the procedure, a gastroscopy is important to rule out serious diseases of the stomach and duodenum. An ultrasound of the abdomen should also be performed in order to detect any existing bile flow disorders – such as gallstones – beforehand. If gallstones are discovered, the gallbladder is usually also removed as a precaution during the biliopancreatic diversion, since later during the desired weight loss other stones can quickly form, which then very often lead to inflammation of the gallbladder and bile duct. Before the operation, an electrocardiogram ( ECG ) and a lung function test are usually also necessary.

course of the operation

Today, biliopancreatic diversion is mainly performed as a minimally invasive operation. This procedure, also known as the “keyhole technique”, does not require a large abdominal incision. Instead, the surgical instruments and a small special camera are inserted into the abdominal cavity through several small skin incisions. Minimally invasive surgeries generally have a lower surgical risk than open surgeries and are therefore particularly suitable for obese patients who already have a significantly increased surgical risk.

Biliopancreatic diversion consists of several surgical steps. Under general anesthesia, the surgeon inserts the instruments and a camera with a light source into the abdominal cavity through several skin incisions. Gaseous carbon dioxide is also introduced into the abdominal cavity during the operation so that the abdominal wall is slightly raised from the organs and the surgeon has a better view and more space in the abdominal cavity.

The stomach is then severed just below the esophagus . At the end of the esophagus, only a small remnant stomach (gastric pouch) remains. The remaining parts of the stomach are removed. In the case of biliopancreatic diversion with a duodenal switch, a so-called gastric sleeve with a significantly smaller volume is formed instead of the gastric pouch.

Next, the surgeon cuts the small intestine about 8 feet before the beginning of the large intestine. The lower part is now pulled up and sewn directly to the gastric pouch or gastric sleeve. The upper part of the small intestine no longer has any connection to the stomach and in future only serves to transport the digestive secretions of bile and pancreas. It is now passed about 50 centimeters above the large intestine into the small intestine and sewn up.

The common piece of small intestine, in which the food particles and the digestive juices mix, is therefore only about half a meter long instead of several meters. Since this is no longer sufficient for complete breakdown and absorption of the food components, these are passed on largely undigested to the large intestine, which in turn hardly absorbs any nutrients. Because it serves above all to thicken the digested chyme.

Operation duration, hospital stay and inability to work

The biliopancreatic diversion takes about two to three hours and is always performed under general anesthesia. The operation usually requires a hospital stay of around eight days – one for preparation and seven for close medical observation after the procedure. On average, about three weeks after the operation, you can resume your professional activity if the course is uncomplicated.

Who is biliopancreatic diversion suitable for?

Biliopancreatic diversion is a procedure for people with obesity and a body mass index (BMI) of ≥ 40 kg/m² (obesity grade III). If there are already metabolic diseases due to being overweight, such as diabetes, high blood pressure or sleep apnea syndrome, biliopancreatic diversion can make sense from a BMI of 35 kg/m².

A prerequisite for biliopancreatic diversion and all other obesity surgery interventions is that all non-surgical measures previously have not shown sufficient success for six to twelve months. These measures include professional nutritional advice, exercise training and behavioral therapy (so-called multimodal concept for obesity). For biliopancreatic diversion, you should be at least 18 and no more than 65 years old, although the operation can also be carried out on younger or older people in individual cases.

In people with extreme obesity (BMI > 50 kg/m²), the operation is sometimes divided into two operations: First, only the gastric sleeve is applied. This should reduce the weight and thus the surgical risk for the second intervention (the actual biliopancreatic diversion).

A malabsorptive procedure such as biliopancreatic diversion is particularly recommended for people who are unable to change unfavorable eating habits. While these people lose weight poorly through other procedures (such as gastric sleeves or gastric bands), a weight reduction can be expected with biliopancreatic diversion due to malabsorption even with persistent unfavorable eating habits.

Who is biliopancreatic diversion not suitable for?

There are various physical and mental illnesses in which obesity surgery such as biliopancreatic diversion is not indicated (contraindicated). Above all, previous operations and malformations of the stomach or intestines can represent important contraindications for biliopancreatic diversion. Psychological comorbidities such as addictions or untreated eating disorders (e.g. “binge eating” or bulimia ) are also exclusion criteria for the intervention. You can find out whether you are suitable for biliopancreatic diversion or not by talking to the surgeon in advance.

Efficacy of biliopancreatic diversion

Biliopancreatic diversion is the surgical procedure that usually achieves the greatest weight loss. In studies, excess weight loss (EWL) after one year was found to be 52 percent for BPD alone and 72 percent for BPD-DS. In addition to the purely cosmetic and psychologically relieving effect, the weight loss after the procedure also has a positive effect on the patient’s metabolism. In many cases, an existing diabetes mellitus is greatly improved or even completely cured by the intervention. Blood sugar levels also normalizeoften shortly after the operation, although the patient has not lost any significant weight at this point. The reasons for this are not yet fully clear. Some researchers suspect that the altered gastrointestinal passage triggers various hormonal changes that have a beneficial effect on energy metabolism.

Advantages of biliopancreatic diversion over other procedures

Since the effect of biliopancreatic diversion is based on two different principles (restriction and malabsorption, see above), the procedure is particularly effective and is particularly effective in people whose obesity is caused by excessive intake of high-calorie foods or drinks. For these people, sometimes referred to as “sweet-eaters”, a gastric reduction procedure such as gastric balloon, gastric band or gastric sleeve would not be sufficiently effective.

Disadvantages and side effects of the procedure

A biliopancreatic division is a surgically demanding procedure. Compared to gastric sleeve surgery, significantly more incisions and sutures are required. The intervention in the digestive system is very pronounced and not completely reversible after successful weight loss. Therefore, one should familiarize oneself with the possible side effects before the procedure. How strong these are in individual cases varies from person to person:

Deficiency symptoms: One of the most common side effects of biliopancreatic diversion is a lack of vitamin D and vitamin B12 : vitamin B12 is absorbed in the last section of the small intestine (terminal ileum ). However, a certain auxiliary protein, the so-called intrinsic factor, must also be present for absorption. Intrinsic factor is made in the stomach. Since a large part of the stomach is removed during biliopancreatic diversion, the formation of the intrinsic factor is reduced and thus the vitamin B12 uptake is also greatly reduced.

Therefore, regular doses of vitamin B12 in the muscles or via the vein into the blood are necessary throughout life. Vitamin B-12 preparations are also available that are absorbed directly through the oral mucosa (sublingual application), but their effectiveness is questionable. It is not yet certain why vitamin D deficiency can occur after biliopancreatic diversion cleared.

Patients with biliopancreatic diversion must be careful to consistently supply vitamins B12 and D – otherwise there is a risk of serious complications such as anemia (anemia due to vitamin B-12 deficiency) and osteoporosis (due to vitamin D deficiency).

Dumping syndrome: Dumping syndrome is the name given to the combination of several symptoms, which can arise from the abrupt emptying of only slightly pre-digested food from the rest of the stomach into the small intestine. Since the pylorus is missing, the concentrated food pulp goes directly into the small intestine. There, following the laws of physics (osmosis), it draws water from the surrounding tissue and blood vessels into the intestine.

This reduces the volume of fluid in the bloodstream , which can lead to a pronounced drop in blood pressure and even collapse. Some people report related symptoms such as dizziness, nausea, sweating, or severe heart palpitations (early dumping). In addition, the high water content of the chyme can cause severe diarrhea.

A dumping syndrome occurs mainly after the intake of osmotically very active (hyperosmolar) food, for example sugary drinks or fatty foods. The dumping syndrome is prevented by the PBD-DS (see above). With this variant of biliopancreatic diversion, the pylorus is preserved.

Loss of muscle mass: Due to the greatly reduced supply of nutrients, there is a relative lack of carbohydrates, which the body tries to compensate for by forming new sugars from amino acids . Amino acids are the building blocks of proteins, which in turn are an important building block for muscles. The body therefore mainly breaks down muscles that are not used much in order to secure the energy balance. Patients after biliopancreatic diversion should therefore counteract the muscle breakdown through increased physical activity. Sports that are easy on the joints, such as cycling, moderate strength training , swimming or aqua jogging , are particularly suitable .

Biliopancreatic diversion: risks and complications

Biliopancreatic diversion involves various general and specific surgical risks. This includes:

  • general anesthetic risks
  • Deep vein thrombosis with the risk of pulmonary embolism
  • Infections in the area of ​​​​external and wound sutures
  • Leaks in the organ sutures on the gastric pouch/stomach or small intestine (suturing insufficiency) with the risk of peritonitis (peritonitis)

In studies, mortality after biliopancreatic diversion was between 0.5 and 7.6 percent. However, these are purely statistical values. The individual surgical risk depends largely on the physical condition at the time of the operation.

post-surgery diet

After biliopancreatic diversion, a basic change in diet is necessary to avoid digestive problems. Apart from that, the weight loss is all the more pronounced the lower the fat and calorie diet you eat after the operation. The following dietary rules must be observed for life after biliopancreatic diversion:

  • Meals may only include small portions (reduced stomach size)
  • every single bite has to be chewed very well, as there is no pre-digestion by the stomach
  • Sugary foods or drinks and very long-fibered meat should be avoided
  • Dietary supplements (especially vitamin D, vitamin B12) must be taken for life

Some medications are also taken in differently or in smaller amounts of active ingredients. Biliopancreatic diversion may therefore require an adjustment in the time and dose of medication taken.

You may also like

Leave a Comment