SADI-S and Sleeve Gastrectomy (SG) are both popular bariatric procedures aimed at significant weight loss and improving obesity-related health conditions. While SG is a simpler and less invasive operation, SADI-S offers additional benefits due to its combined approach of restriction and malabsorption. Understanding the differences between these procedures in terms of benefits, side effects, and potential complications can help patients and healthcare providers determine the most appropriate choice.
Benefits of SADI-S Compared to Sleeve Gastrectomy
- Enhanced Weight Loss
SADI-S combines two mechanisms for weight loss: restriction (by reducing stomach size) and malabsorption (by bypassing a portion of the small intestine). This dual approach generally leads to more substantial weight loss compared to SG, which only restricts food intake by reducing the size of the stomach.
SG is effective for weight loss, but for patients requiring more significant weight reduction, especially those with a higher body mass index (BMI), SADI-S may offer better outcomes.
- Improved Metabolic Outcomes
SADI-S not only restricts the amount of food that can be consumed but also changes the hormonal environment of the gut, resulting in greater improvements in metabolic conditions such as type 2 diabetes. The hormonal changes from rerouting the intestines promote increased levels of GLP-1 and PYY, which help control blood sugar and appetite.
SG also reduces levels of ghrelin (a hunger hormone), but the hormonal changes are less pronounced compared to SADI-S, making SADI-S more effective for patients with poorly controlled diabetes or other metabolic conditions.
Side Effects of SADI-S Compared to Sleeve Gastrectomy
- Higher Risk of Malabsorption
While the addition of malabsorption in SADI-S enhances weight loss, it also increases the risk of nutritional deficiencies. Patients undergoing SADI-S are at higher risk of deficiencies in essential nutrients like iron, vitamin B12, calcium, and fat-soluble vitamins (A, D, E, K).
SG does not involve intestinal bypass and therefore has a lower risk of nutritional deficiencies. Patients undergoing SG generally only require basic vitamin and mineral supplementation.
- Diarrhoea and Steatorrhoea
The shorter length of the small intestine available for nutrient absorption in SADI-S can lead to diarrhoea or fatty stools (steatorrhoea), especially with high-fat diets. Adherence to dietary recommendations and regular follow-up is essential to manage these symptoms.
In SG, changes in bowel habits are usually less pronounced, with most patients experiencing manageable symptoms such as mild constipation or occasional diarrhoea.
Complications of SADI-S Compared to Sleeve Gastrectomy
- Duodenal Stump Blowout (SADI-S Specific)
SADI-S carries a unique risk of duodenal stump blowout, which occurs when there is a leak or rupture at the closed end of the divided duodenum. This serious complication can lead to peritonitis and sepsis, requiring urgent surgical intervention. This complication is not encountered in SG since the duodenum is not transected in that procedure.
- Anastomotic Leaks
SADI-S involves creating an anastomosis between the duodenum and the ileum, which carries a risk of leaks at the connection site. Prompt recognition and management of leaks are crucial to prevent severe complications.
SG does not involve an intestinal anastomosis, reducing the risk of leaks compared to SADI-S. However, there is still a risk of staple line leaks where the stomach is cut and stapled.
- Nutritional Deficiencies
SADI-S patients face a higher risk of developing nutritional deficiencies due to the bypass of a significant portion of the small intestine. This requires lifelong supplementation and close follow-up to monitor nutrient levels.
While SG patients also need supplementation, the risk of severe deficiencies is lower compared to SADI-S, as the small intestine remains intact, allowing for more normal nutrient absorption.
- Revisional Surgery Requirements
SADI-S may require revision in cases of severe malabsorption, unmanageable diarrhoea, or nutritional deficiencies. Conversely, SG patients may need conversion to another procedure if there is significant weight regain or if the procedure fails to provide sufficient weight loss.
- Development of worsening of acid reflux
Both SADI-S and Sleeve Gastrectomy involve the creation of a sleeve gastrectomy, where a significant portion of the stomach is removed, leaving behind a tubular-shaped stomach. This alteration in anatomy increases the risk of gastro-oesophageal reflux disease (GORD), as the higher pressure within the smaller stomach can lead to acid reflux. Because both operations share this anatomical change, they are associated with an increased risk of acid reflux, making them less suitable for patients who already have significant GORD. For individuals with pre-existing acid reflux, other bariatric procedures, such as Roux-en-Y Gastric Bypass (RYGB), may be more appropriate due to their beneficial effect on reducing acid exposure.
Both procedures emphasize the importance of lifelong follow-up and monitoring to address any complications that may arise.
Conclusion
SADI-S and Sleeve Gastrectomy each have distinct benefits and limitations. SADI-S offers greater weight loss and improved metabolic outcomes due to its stronger metabolic part. However, it comes with an increased risk of nutritional deficiencies, diarrhoea, and complications such as duodenal stump blowout.
Sleeve Gastrectomy is a simpler procedure with a lower risk of nutritional deficiencies and fewer complications related to intestinal rerouting. However, it may not provide as significant weight loss or metabolic benefits as SADI-S, particularly for patients with high BMI or uncontrolled diabetes.
Both SADI-S and Sleeve Gastrectomy narrow the stomach, creating higher internal pressure and thereby increasing the risk of acid reflux.
