Dumping After Bariatric Surgery: Causes, Symptoms & Treatments

July 29, 2019

Dumping is a very common question bariatricians are asked when Roux-en-Y gastric bypass is recommended as a potential treatment option for morbid obesity. Before we address the issue of dumping after bariatric surgery, we should review the anatomy of the Roux-en-Y gastric bypass, to understand the reason dumping syndrome occurs.

With normal digestive anatomy, after you chew your food, it passes into the esophagus and then into the stomach. At the end of the stomach, there is a small muscular valve called the pylorus. This valve stops food from moving along into the small intestine until it is broken down into semi-liquid form and partially digested.

Digested food will transit through the duodenum, which is the 1st portion of the small intestine and, slowly makes its way through the jejunum and the ileum. Finally, it reaches the large intestine and out through the anus in the form of stool (which is undigested food mixed with intestinal juices and mucous to help it move through the digestive tract).

The diagram on the right describes the change in the anatomy after Roux-en-Y gastric bypass. A small pouch is created from the stomach, the small intestine is then rerouted, and food from the gastric pouch (new stomach) is emptied directly into the small intestine. The rest of the stomach is left behind as a blind loop, however, it continues to make digestive juices and enzymes, these are very important for digestion and absorption of nutrients. The green arrow shows the drainage route for stomach, liver, gallbladder and pancreatic digestive juices. When the green and red arrows meet food digestion starts. This delay in the digestion is referred to as the ‘malabsorptive’ part of RYGB surgery.

The small gastric pouch limits the amount of calories one can consume and will help in maintaining the weight loss in the long run.  The mechanism of weight loss is more complex than simply making your stomach smaller, we believe the most powerful effect of weight loss surgery is through manipulation of the body and therefore reformatting the metabolic/hormonal status.

So, What is Dumping Syndrome Exactly?

Because your stomach is much smaller now and it’s connected directly to your small intestine, after chewing your food it’s immediately dumped it into your small intestine. You may ask what is the problem with that isn’t the small intestine made to absorb food? You would be correct in assuming that. But, the small intestine is not made to receive liquid or semi-liquid meals with a large number of carbohydrates, in the form of refined sugars i.e. milkshake, ice cream, or any other high sugar content drink which have not been partially digested. If these meals transit very fast into the small intestine it causes significant metabolic changes, which the small intestine cannot handle.

The first change occurs when a large amount of sugars suddenly enter the small intestine. Refined sugars attract a large amount of fluid into the small intestine, causing the fluid to be sucked out of the cell and this will cause transient dehydration.

Imagine if you drink fluid but, instead of adding fluid to your cells, it sucks the fluid from them. Our bodies are made of 70% water, which means it cannot function if the water reserve is depleted. Also, because this happens very rapidly the symptoms of severe dehydration occur very fast. This usually occurs 10-30 minutes after you consume a meal and it’s called Early Dumping Syndrome.

Patients describe a sudden sensation of light-headedness, palpitations, weakness, chest tightness/discomfort and a feeling of passing out. These symptoms occur shortly after consuming carb-rich meals. Patients lay down to lessen the effects of these symptoms, which resolve over a period of 20-40 minutes.

Unfortunately, this is the first part of a double whammy. As soon as these symptoms resolve the second constellation of changes occur.

The high sugar content in the meal is absorbed into the bloodstream, which causes a surge in the blood sugar level; this usually leads to a sensation of feeling good and energetic. High sugar levels are not good for us and so the body will attempt to normalize the blood sugar. It does so by releasing insulin, however, this will lead to a sudden drop in sugar level which leads to the emergence of the previous symptoms yet again. This can occur anywhere between 1.5-3 hours after eating and it’s called Delayed or Late Dumping Syndrome.

Once again, the patient will feel light-headed, fatigued, palpitation and a feeling of passing out. Again, patients will lay down to combat these severe and sudden symptoms. In fact, when I ask patients to describe what happens to them they say ‘I felt as if I was going to die!’

The symptoms of dumping syndrome are very uncomfortable, in most cases, it resolves without causing any danger to the body. Nevertheless, if you were driving after stopping at a fast-food drive-thru and consumed the wrong type of meal it can be very serious as you may lose control and hurt yourself and other innocent people. Dumping syndrome can be experienced even for long-term post-ops.

Dumping After Bariatric Surgery Treatment Options

The main premise of treatment is prevention. I frequently tell patients “dumping syndrome is your body’s way of telling you this meal is bad for you and you should avoid it!”

Consuming protein first, followed by a smaller amount of complex carbohydrates, wait for 45 minutes and then consume your fluids. This sequence of oral intake will significantly decrease the chances of having dumping syndrome.

Also, avoid sweets and sugars such as candy bars, chocolate, hard candy, soda pop, fruit juice, fruit punch, large quantities of fruit, mints, suckers, jelly, honey, table sugar,  syrups, high sugar protein bars, some types of gum, cookies, pie, cake, and other dessert items.

You may also want to lay down or sit in a recliner chair 15-20 minutes after eating, it may slow passage of food through your intestinal tract.

If the above treatment is not effective, due to an enlarged gastrojejunostomy (the connection between your stomach and small intestine) and food is transiting very fast from your pouch into the small intestine. An increasing amount of fiber such as psyllium (Metamucil, Konsyl, etc) or methylcellulose (Citrucel) allows the food to bulk-up and slows its transit through your gastric pouch and small intestine.

Should all of these dietary changes prove unhelpful then surgical revision may be warranted. You must see an experienced bariatric surgeon to discuss potential surgical treatment options.

ABOUT THE AUTHOR Dr. Husain Abbas of Memorial Advanced Surgery, is a Board Certified surgeon trained in Minimally Invasive Surgery. After his surgical residency at St. Mary's, a Yale University affiliated hospital, Dr. Abbas completed a fellowship in Minimally Invasive Gastroesophageal & Bariatric Surgery at the University of Florida, Gainesville. Dr. Abbas' expertise extends to a wide array of gastroesophageal disorders, anti-reflux surgery, complex hernia repairs, endocrine, oncology and bariatric procedures. Read more articles from Dr. Abbas!

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