Over my bariatric career, I’ve performed over 1,800 duodenal switch cases and I’m a consultant for Ethicon Endo-Surgery, a medical device company in the Johnson and Johnson family. One part of my practice is teaching other surgeons how to properly perform the Duodenal Switch so they can offer it to their patients.
The duodenal switch is my favorite procedure because my patients lose more weight, resolve other conditions like diabetes, high blood pressure and sleep apnea better than the sleeve gastrectomy and gastric bypass.
It also addresses the most devastating complication associated with ANY bariatric surgery:
The duodenal switch gives my patients the best long-term weight loss out of all available bariatric surgical procedures. If that sounds interesting to you then keep reading to learn exactly what makes the duodenal switch so great.
Table of Contents:
- What is the Duodenal Switch?
- How it’s different than other procedures?
- What is a “Bowel Bypass?”
- Who should consider the Duodenal Switch?
- The Duodenal Switch and Diabetes Resolution
- Is it better than the Gastric Bypass and VSG?
- Complications that can arise from the Duodenal Switch
- How much does it cost?
- Recovering after DS Surgery
- “When can I go back to work?”
- Revision Surgery: Converting a Sleeve to a DS
- Questions to ask your Surgeon about the Duodenal Switch
- The Bottom Line on the Duodenal Switch
The duodenal switch is a surgical procedure that combines aspects of a limited sleeve gastrectomy and an intestinal bypass (like we do in gastric bypass surgery).
The Sleeve Gastrectomy Part:
The Vertical Sleeve Gastrectomy (VSG) is currently the most commonly performed bariatric surgical procedure. The surgeon removes a large portion of your stomach leaving you with a stomach approximately 10% of its original size.
The new, smaller stomach is about the size and shape of a banana. It limits the amount of food you can eat by making you feel full after eating small amounts of food.
The Duodenal Switch procedure utilizes the same “sleeving” of the stomach as the VSG, but generally, less of the stomach is removed so that patients are not as “restricted” when eating protein.
The lower intestine is then divided (similar to the RNY Gastric Bypass) much further downstream than with gastric bypass so that half or more of the intestine is bypassed.
This is the intestinal bypass portion of the operation.
How it’s different than other procedures?
The duodenal switch is significantly different than any other bariatric surgical option. I mentioned that this sleeve gastrectomy that was performed is limited. That is the stomach is intentionally left larger so that the switch patient can eat all the protein that they need without having too much restriction.
While the duodenal switch includes a bowel bypass, it’s more significant than the bowel bypass used in the RNY Gastric Bypass. But to understand why this matters, it’s best to understand exactly what is a bowel bypass…
What is a “Bowel Bypass?”
In order to understand digestion (both before and after bariatric surgery), it is important to understand the organs of the intestinal tract as well as where macronutrients are absorbed. Macronutrients in the food we eat are protein (4 calories per gram), carbohydrates (4 calories per gram) and fat (9 calories per gram).
After swallowing food, the food progresses to the:
- Esophagus where there is no absorption of any calories or nutrients — then to the…
- Stomach, where there is also no absorption of nutrients, next, is the…
- Small intestine where all macronutrient and micronutrient (vitamins and minerals) are absorbed, finally to the
- Colon where primarily water is reabsorbed.
So, when we are talking about bowel bypass with bariatric surgery we are really talking about the small intestinal bypass. A small intestinal bypass means that the food that is eaten no longer goes through all of the small intestines.
After sleeve gastrectomy, there is no small bowel bypass so food goes through all of the small intestines and there is no calorie malabsorption. After gastric bypass food still goes through 85-90% of the small intestine and there is only a small amount of fat malabsorption and no malabsorption for protein or carbohydrates.
After the duodenal switch, 50% or more of the small intestines are bypassed and this results in significant calorie malabsorption such that the DS patients only absorb about half of the calories from the food that they eat.
So, the intestinal bypass with the duodenal switch is different than the bypass performed for the gastric bypass. With the Roux-en-Y gastric bypass very little of the small intestine is bypassed (10-15%), whereas with the duodenal switch at least 50% or more of the small intestine is bypassed.
In the diagram above the bypassed portion of the small intestine is labeled as the “Biliopancreatic Limb.” This is significant because the small intestine is where we absorb all of our calories.
This means that calorie absorption for protein and carbohydrates after Roux-en-Y gastric bypass is NORMAL!
Most people are under the impression that calorie absorption after gastric bypass is poor. While there is a little malabsorption for fat, absorption of protein and carbohydrates is pretty much the same as before surgery.
In my experience, patients who don’t lose enough weight or struggle with regaining weight after gastric bypass (and sleeve gastrectomy), it is almost always due to eating too many carbohydrates since they are absorbing practically all of the calories from carbs.
Whereas with the duodenal switch patients are only able to absorb about half of the calories that they consume!
How does that work? Since calories are primarily absorbed in the small bowel and the bowel bypass is greater after the duodenal switch, you would only be able to absorb about 60% of the protein, 60% of the carbohydrates and only 30% of the fat from the food you eat.
This means that you can only absorb about half of the calories from the food.
I believe that this is why weight loss is better and why patients rarely regain weight after the duodenal switch.
Most patients who struggle with weight regain are eating a high carb diet, snacking on carbs and are inactive.
Who should consider the Duodenal Switch?
The duodenal switch is an excellent option for anyone suffering from severe obesity, but, it is especially advantageous for people whose BMI is over 50 because the percentage of excess weight loss is greater.
For example, the expected excess weight loss for someone in the “super obese” category after a sleeve gastrectomy or gastric bypass is only about 50%. But, with a duodenal switch, it’s more like 70% excess weight loss with a risk of weight regain of only 2-3%!
The Duodenal Switch and Diabetes Resolution
The duodenal switch is also particularly advantageous for patients with severe diabetes because the resolution rate for diabetes is highest and most durable after duodenal switch when compared with the resolution and durability obtained after gastric bypass or sleeve gastrectomy. After sleeve gastrectomy, initial diabetic resolution rates are around 70%.
Diabetes comes back in about 30-50% of patients after approximately 5-10 years. If the diabetes recurs it’s usually easier to treat than it was before. With the Roux-en-Y gastric bypass, initial diabetic resolution rates are probably closer to 80% with a recurrence rate after 5-10 years of around 30%. Again, like the sleeve, it’s usually easier to treat if it does recur. But this is where the duodenal switch is different. Depending on the studies you read, initialed diabetes resolution rates after duodenal switch are 95-100% and this resolution is durable for 15-25 years!
It should be noted that with all surgeries if the patient has been on insulin for more than 8-10 years the likelihood of them getting completely off of insulin is reduced. This has been shown in multiple studies.
Is it better than the Gastric Bypass and VSG?
There are pros and cons to all of the bariatric surgical options. However, I do believe that the duodenal switch is better than the gastric bypass and the sleeve gastrectomy because patients lose more weight, have a lower risk of gaining the weight back and are more likely to get rid of their diabetes, high blood pressure and sleep apnea after duodenal switch than they are with the other options.
Data taken from Dr. Boyce’s Practice
As you can see, after 24 months all four bariatric procedures produced excess weight loss; however, the Duodenal Switch procedure continues to cause lasting weight loss and more weight loss over time.
Complications that can arise from the Duodenal Switch
The medical literature shows that there is a higher risk of complications after duodenal switch than after gastric bypass and sleeve gastrectomy. The duodenal switch is more complicated because it involves dividing the duodenum and involves a longer bowel bypass as described previously. The duodenum is a potentially complicated dissection because of its proximity to the common bile duct and the pancreas.
While it is a more complicated operation, another consideration for why the Duodenal Switch presents a higher risk for complications is that it’s performed on patients who have a higher body mass index and more medical problems.
Patients who start with a higher BMI have much thicker abdominal walls, more intraabdominal adiposity, larger livers, more systemic inflammation and less cardiopulmonary reserve than lower BMI patients all of which puts the patient at a higher risk for complications.
In my hands, the risk of bleeding complications and anastomotic leakage is equivalent to a duodenal switch and the gastric bypass. I believe that the risk of blood clots and pulmonary embolization is more patient dependent than it is on the surgical procedure being performed.
Longer operations do have a higher risk of deep venous thrombosis and pulmonary embolism but it only takes me 30 minutes longer to perform a duodenal switch than it does a sleeve gastrectomy.
The unique complications that occur after bariatric surgery differ between the different operations. For example, after sleeve gastrectomy, we are concerned about postoperative weight regain, staple line leakage and worsening heartburn. Complications unique to the Roux-en-Y gastric bypass include weight regain, marginal ulcer formation and the dumping syndrome.
After duodenal switch we have not seen worsening reflux, dumping syndrome, weight regain, high rate of staple line leaks or marginal ulceration. My greatest concern with a duodenal switch is that there is a higher risk of nutritional problems particularly protein malnutrition and fat-soluble vitamin deficiencies.
How much does it cost?
The cost of surgery can vary since it largely depends on whether it is a covered benefit on your health insurance plan. If it is a covered benefit the out-of-pocket cost to the patient will depend on how the insurance policy is written. For example, a typical coinsurance split is an 80/20 policy.
This simply means that the insurance would pay for 80% of the cost and the patient will be responsible for the remaining 20%.
If bariatric surgery is a noncovered benefit or the patient does not have health insurance the cost for a self-pay duodenal switch varies throughout the country between about $20,000-$30,000.
That would include the surgery, anesthesia, hospitalization and usually follow-up care for a year.
Recovering after DS Surgery
Generally the night before your surgery you’ll be on a diet of clear liquids by mouth. Since we are operating on your stomach and digestive tract we don’t want any food remnants that could cause an infection.
The surgery normally takes around 2-4 hours. It takes longer than the sleeve and gastric bypass since it’s more involved.
After the surgery, you typically stay in the hospital for two nights for an uncomplicated surgery. Of course, if there are complications the length of your stay will vary.
The morning after your surgery you’ll get started on the liquid phase of your 4-Phase Bariatric Diet with emphasis on getting 30 grams of protein and 64 ounces of fluid in the first 24 hours post-surgery.
When you go home after you leave the hospital I tell my patients that they will be able to be relatively independent. I tell them they can bathe themselves, walk up steps, they’ll be able to lift a jug of milk (8-10 lbs) and be able to drive a car within a week.
“When can I go back to work?”
Returning to work depends on the type of work that you do. If it’s a desk job I tell my patients that they can go back to work in about 1-2 weeks. But if they have a job that requires unrestricted activity, then it’s going to be 4-6 weeks before you go back to work.
Revision Surgery: Converting a Sleeve to a DS
For any bariatric patient who has previously (or plans to have) the vertical sleeve gastrectomy (VSG), you’ve set up perfectly to be converted to the duodenal switch if you wish.
Since you’ve already been sleeved, this basically means your surgeon can finish the duodenal switch by adding the bowel bypass.
Why would someone convert to a DS?
The revision surgery is usually done in order to help the patient lose more weight or to resolve their diabetes. Since the DS outpaces the VSG in both diabetes resolution and long-term weight loss this can actually be a strategic decision.
It’s common for a surgeon to perform the DS in stages. Meaning they plan to first do the sleeve on a patient, allow them time to lose weight and lower their BMI to lower complications for the bypass portion of the procedure.
Key considerations for revision surgery
The patient needs to understand the nutritional implications of this conversion surgery. Afterward, the patient will need to consume almost twice as much protein daily in order to absorb the necessary protein for good health. The patient will also need to take more vitamin and mineral supplements than they needed after sleeve gastrectomy.
Questions to ask your Surgeon about the Duodenal Switch
Because the Duodenal Switch is such an involved and technical procedure, it’s important that you “interview” your surgeon during your initial consultation.
Here are some questions you should ask:
- How many duodenal switches have they performed?
- What are the complication rates for bleeding, anastomotic leakage, deep venous thrombosis, pulmonary embolism and death?
- What are their recommendations for maintaining good nutrition after duodenal switch?
- What are the unique complications associated with the DS?
- How are supplements different for duodenal switch patients compared to other bariatric procedures?
The Bottom Line on the Duodenal Switch
Special care and research should be done on the patient’s side before diving into the DS procedure head first. Make sure that your surgeon has adequate experience and make sure you have a full understanding of the nutritional considerations.
You need ~2x the amount of protein and will have specific and greater vitamin & mineral supplement needs (compared to RNY and VSG) for life.
The duodenal switch is a great option for patients who like to eat protein and want to maximize their weight loss, minimize the risk of weight regain and get healthy!