Bariatric Surgery FAQ

Duodenal Switch Complications

Duodenal Switch Complications - Bariatric Fusion

Any surgical procedure performed comes with the risk of complications. A duodenal switch procedure comes with the possibility of various complications.

Out of all the weight loss procedures that are available, the duodenal switch is highly effective for weight loss, but is one of the riskier surgeries that comes with a higher chance of complications.

There are short-term and long-term complications that are possible. Some of these complications are detrimental to your health and can be exceptionally dangerous, whereas others are more of an inconvenience than anything else.

In this article, we will discuss the most common complications that occur so that you have a good understanding of exactly what the procedure can entail, and are fully prepared when going into it.

What This Article Covers:

Duodenal Switch Explained

Complications of duodenal switch

Since there are a number of weight-loss surgeries available, it is easy to get confused between them all.

A duodenal switch surgery consists of two parts. It combines surgical methods that cause malabsorption and restriction.

The malabsorptive part consists of bypassing a large portion of the small intestine, so that fewer nutrients and calories are absorbed by the body.

The restrictive part consists of a gastric sleeve surgery where the stomach is made into a smaller, "sleeve" pouch.

This is one of the most complicated, but successful weight loss surgery options.

Short-Term Complications Post Duodenal Switch Surgery

Blood Clots

Although blood clots occur very rarely and are only found in about 1% of patients, the risk is still there.

The most common type of blood clot that presents itself post-op is deep vein thrombosis.

This is usually prevented by prescription blood-thinning medications and moving as soon as medically feasible after surgery.


As with any operation, there is a chance of infection around the incision site.

Common signs of infection include increased pain, redness, warmth, and swelling, pus coming out of the incisions, red lines around the incisions, and a fever.

Due to the risk of infection, it is important that you take your post-operative care seriously in order to prevent the occurrence of infection.

Difficulty Ingesting Liquids Post Surgery

Straight after surgery, there is a lot of swelling that occurs. This makes swallowing and ingesting liquids difficult and painful for the first few days post-surgery.

Although it may be difficult, ensure you are sipping small amounts of fluid throughout the day.

Once the swelling goes down this usually resolves and ingesting liquids becomes more pleasant again.

Dehydration Due to Swelling

Swelling makes the new stomach pouch even smaller and inflamed. Therefore, you will not be able to hold much fluid.

This, along with the fact that the swelling can also make it painful to ingest water, often leads to an insufficient intake of water, which can cause the very common complication of dehydration after bariatric surgery.

Stomach Leakage

A post-gastrectomy duodenal leak, also known as a duodenal stump leak, is one of the worst and most serious duodenal switch complications that can occur.

A duodenal stump blow-out is what leads to the leakage and is only seen in 1-3% of bariatric surgery cases.

A stump blow-out happens when pressure and inflammation caused by a distal obstruction or a number of other factors occurs.

There are various things that can cause a stump blow-out. This includes the duodenal stump not being closed properly, adhesions that present from the operation, intra-luminal hematomas, suturing that causes ischemia and necrosis, and various other reasons.

This complication is dangerous and you should notify a healthcare provider immediately. As recorded, stump blow-outs have led to increased morbidity and mortality rates.


Constipation after sleeve gastrectomy, duodenal switch surgery, and gastric bypass is a common complication.

Luckily, this complication usually only lasts for about 6 months post-operation, and usually resolves on its own.

If you are having issues, consult with your dietitian for an adjustment in your diet plan to include more water and fiber sources.

Internal Bleeding

Post-operative internal bleeding is also a concerning complication.

It is required to find the source of the bleed and correct it. Sometimes, it may require a blood transfusion.

This can be caused by possible injury to organs and ulcers to name a few.

Long-Term Complications Post Duodenal Switch Surgery

Nutritional Deficiencies

Duodenal switch causes severe malabsorption and restriction. During the procedure, the anatomy of the small intestine is rerouted in such a way that a large portion of the small intestine is bypassed.

Since a portion of the small intestine is bypassed, the pancreatic enzymes and bile are only in contact with food at the distal end of the small intestine. This means that fewer nutrients and calories are able to be absorbed from the intestinal tract.

duodenal switch surgery complications

While this is helpful for weight loss, it often leads to nutritional deficiency if the proper supplements are not taken lifelong for prevention. This presents as one of the most problematic and common complications of a duodenal switch.

Although, other bariatric surgery procedures increase the risk of nutritional deficiencies, due to the extensive bypassing of the small intestine in duodenal switch surgery, patients will see a higher risk of fat-soluble vitamins that are not as big of a problem for other bariatric surgeries.

Fortunately, there are supplements that exist to help combat this, such as ADEK chewable multivitamins for bariatric patients. These supplements are specifically formulated for duodenal switch patients, targeting the higher risk of deficiency for the fat-soluble vitamins A, D, E, and K.


As a result of the malabsorption issues that we spoke of above, people who undergo duodenal switch often suffer from calcium and vitamin D deficiencies.

A lack of these two nutrients can cause brittle bones over time, as well as the onset of osteoporosis.

Gastroesophageal Reflux Disease

Gastroesophageal reflux disease, or GERD, is something that most obese individuals suffer with.

While other types of weight loss surgeries have the ability to make GERD partially better, unfortunately the gastric sleeve component of duodenal switch surgeries actually can make it worse for some individuals.

This is a very unpleasant complication, but is something that can also be treated with medication and diet changes.

Excessive Gas

Flatulence and burping after gastric sleeve are very common.

Excessive gas can occur for a number of reasons including diet alterations. Carbonation can cause this issue, as well as eating too fast and eating too much.

Individuals with GERD will also have an issue when consistently swallowing air to clear acid from the esophagus.

Dumping Syndrome

People who undergo weight loss surgery suffer from a complication called “dumping syndrome”.

Dumping syndrome can happen anywhere from minutes to hours after you eat certain meals post-op.

It occurs when food is “dumped” straight from your stomach into your small intestine and is not properly digested. This often results in gastrointestinal issues, like diarrhea.

Other symptoms of dumping syndrome include nausea, lightheadedness, increased heart rate, bloating and abdominal pain.

Unfortunately, dumping syndrome is one of the duodenal switch and gastric bypass side effects.

There is nothing that can be done to treat it, but it can be managed by addressing which foods you have trouble tolerating. Typically, foods that cause dumping syndrome are high in sugar and/or fat.

Hair Loss

Hair loss after gastric bypass, duodenal switch, and any weight loss surgery, is one of the most common complications.

Although hair loss is common after all types of weight loss surgeries, it is more extreme after a duodenal switch surgery. This is because post-operative hair loss normally occurs due to a combination of protein and vitamin deficiencies, inflammation, and stress of surgery.

Since duodenal switch leads to a decreased surface area for nutrient absorption to take place in the small intestine, malabsorption is more prominent.

Eating Disorders

Many obese individuals who qualify for duodenal switch surgery tend to have some sort of disordered eating. Typically, binge eating is common in this population.

However, after duodenal switch, binge eating isn't physically possible due to the smaller stomach size.

Unfortunately, disordered eating tendencies can linger and present as vomiting after gastric sleeve surgery and duodenal switch surgery or anorexia after gastric sleeve and duodenal switch surgery.

If you feel you are dealing with disordered eating, it is important to have a conversation with a qualified healthcare provider to address the issue.


Depression after bariatric surgery is another long-term complication that is quite common.

Complications of duodenal switch surgery

Depression can occur for a number of reasons, including food no longer being used as a coping mechanism, expecting more weight loss than you experience, missing out on social events, and dietary changes.

There may also be signs of depression when hitting a weight stall. A stall can be for a short period of time or last up to a month. This is completely normal and should be expected for the body to adjust to the extreme changes of surgery and weight loss. However, some individuals can fall into a state of depression due to this.

Depression is a very serious medical condition and should be addressed with your healthcare provider.

Hiatal Hernias

Hiatal hernia after gastric sleeve and duodenal switch surgery is another possible complication that can occur.

A hiatal hernia is a condition when the stomach bulges through the diaphragm. This is usually due to weakness or a tear in your diaphragm that allows the stomach to protrude.

Hiatal hernias are very common in those who are obese, so it’s likely that some patients may present with them before the operation.

Hiatal hernias and GERD tend to have a link, and Hiatal hernias can make the symptoms of GERD even worse.

A lot of people only develop Hiatal hernias after the operation. The reason for this is due to a significant change in intra-abdominal pressure that occurs post-surgery.

Another reason can be due to rapid weight loss after the surgery. It causes the Hiatal orifice to become enlarged and possibly affect the pillars and strength of the diaphragm.


There are possible complications that can occur with any bariatric surgery procedure. However, duodenal switch surgery presents with a higher risk of complications.

Luckily most of them are not life-threatening, but it is still important to gather knowledge and decide if surgery is worth the possibility of complications occurring. It’s also important to take the proper precautions in order to prevent complications from occurring.

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**This blog is for information and education purposes only. This information is not intended to substitute professional medical advice, diagnosis, or treatment. Please consult with your physician or another qualified health provider with any questions in regards to a medical condition.

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