Sleeve Gastrectomy and Dumping Syndrome

What is Dumping Syndrome?

Dumping Syndrome is a collection of symptoms that occur after eating resulting from rapid delivery of stomach content into the small intestine. Symptoms can range from mild to severe. Normally there is a muscle sphincter (the pylorus) at the lower end of stomach that regulates the slow delivery of broken down food into the intestine. Therefore, dumping syndrome is very common in operations that bypass or remove the pylorus such as stomach cancer surgery and gastric bypass (85% of patients). Dumping syndrome is also seen in some patients having other stomach operations such as sleeve gastrectomy.

Dumping Syndrome and Sleeve Gastrectomy

The resection of around 85% of stomach in sleeve gastrectomy results in major changes in the anatomy and function of the stomach. Even though the pylorus valve is maintained, the new stomach tube has a very limited capacity (around 150 mL) resulting in rapid emptying of the stomach content into the intestine.
After sleeve gastrectomy very few patients experience true dumping syndrome, however, studies that used a glucose provocation test showed that around 25% of patients develop symptoms of dumping syndrome with glucose provocation. In general these symptoms are milder than those experienced by patients with gastric bypass. The symptoms tend to improve after the first year. 

What Brings About Dumping Syndrome After Sleeve Gastrectomy?

Dumping syndrome usually occurs due to poor food choices. The ingestion of refined sugars (e.g. non-diet soft drinks and sweets) or food with high glycaemic index are the most common triggers for the symptoms. 

What are consequences of having dumping syndrome?

Symptoms of dumping syndrome can make you feel awful and it can be difficult to manage. The good news is that because dumping most often occurs after bad food choices (e.g. sweets) you will quickly learn not to eat it again. This is called negative reinforcement.

Types of Dumping

There are two types of dumping symptoms

1. Early Dumping:

• Usually start within 20-30 minutes after meal and can last for up to 60 minutes. It includes gastrointestinal symptoms and vasomotor symptoms.
• Gastrointestinal symptoms: include abdominal pain, diarrhoea, audible intestinal sounds, nausea and bloating.
• Vasomotor symptoms: include fatigue, a desire to lie down after meals, facial flushing, palpitation, sweating, weakness, low blood pressure and fainting.
• Early dumping occurs because of excessive secretion of gut hormones after the rapid flow of undigested food into the small intestine. This shifts fluid from the blood into the small intestine.

2. Late Dumping:

• Usually start 1-3 hours after the meal and includes symptoms of reactive hypoglycaemia (low blood sugar) such as sweating, palpitation, hunger, fatigue, confusion, difficulty concentrating, aggression, tremor and fainting.
• Late Dumping occurs because the rapid delivery of a high concentration of carbohydrates into the small intestine leads to a raised blood sugar. This is countered by excess release of insulin which brings blood sugar down and result in the subsequent reactive hypoglycaemia (low blood sugar).
• Late dumping is less common than early dumping and only a minority of patients have symptoms of both.

Diagnosis of Dumping Syndrome

Dumping syndrome is diagnosed based by the symptoms patients experience. See the Sidstad's scoring system below. 

Often the diagnosis is confirmed by a dumping provocation test using oral glucose or by a stomach empty study.

Management of Dumping

Dietary modification is the main way to manage dumping syndrome by avoiding refined sugars, high glycaemic / simple carbohydrates and other food items that bring the symptoms. This is best done under the guidance of our experienced bariatric dietitian.

• Avoid the following food items:

1. 1. Sugar or high fructose corn syrup (present in most soft drinks including sweetened fruit juices)
   2. Muffins
   3. Cookies
   4. Chocolate
   5. Cakes
   6. Candy

• Don't drink liquids 30 minutes before or after meals and certainly no liquids while eating.
• Use artificial sweeteners such as Splenda or Equal instead of sugar. However, avoid drinks containing sorbitol (sorbitol acts as a laxative)
• The only form of carbohydrates to have after weight loss surgery is complex carbohydrates such as whole-wheat bread.

Early dumping almost always settle with this.
Late dumping that does not improve with diet modification may require medications such as Acarbose or Octreotide.