Evaluation of the advantages, disadvantages and complications of a recently innovated procedure (Single anastomosis sleeve ileal "SASI" bypass) of the more traditional laparoscopic sleeve gastrectomy "LSG"

Obesity is a major health problem affecting over 1.7 billion people. Obesity is defined as excess body weight due to abnormal or excessive fat accumulation that presents a risk to health. A crude popular measure of obesity is the body mass index (BMI), a person's weight (in kilograms) divided by the square of his or her height (in meters). A person with a BMI of 30 or more is generally considered obese. A person with a BMI equal to or more than 25 is considered overweight.

Obesity is a major risk factor for a number of chronic diseases, including diabetes mellitus, cardiovascular diseases and cancer. It is associated with significant co-morbid conditions and reduced life expectancy. Since 1997, obesity has been officially recognized by the World Health Organization as a global epidemic.

Bariatric surgery has been shown to be the most successful approach in managing morbid obesity that can achieve and sustain great weight loss for a long period.

Common strategies of bariatric surgery are: mechanical obstacles to food ingestion, nutrient-excluded segments and malabsorption, which are a potential cause for complications and should better be avoided from a strictly physiological prospect. Also, such procedures necessitate lifelong medical supervision with the supplementation of vitamins and nutrients. Moreover, they are frequently associated with dysphagia and vomiting as a result of anatomical restrictions.

Laparoscopic sleeve gastrectomy (LSG) was initially established as the first stage of a two stage bariatric approach. It is now used as a primary bariatric procedure because of documented excellent weight loss and an acceptable risk of complication. Advantages include the avoidance of implantable material, maintenance of gastrointestinal continuity, avoidance of malabsorption, and convertibility to other operations. However, The major disadvantage of LSG is the severity of the major postoperative complications like bleeding and staple-line leakage. Staple-line disruption is the most life-threatening complication after LSG, Leaks after sleeve gastrectomy (SG) mostly occur because of the creation of a high internal pressure pouch.

Our understanding of digestive physiology is now changing and the interacting neuroendocrine signals that control hunger, satiety, and energy expenditure are better understood now. The role of GI tract in satiety is a sum of a mechanical sensation of a full stomach, rapidly confirmed by neuroendocrine signals that recognize whether the ingested was indeed nutritive. In terms of meal termination, the most important of these postprandial neuroendocrine signals are an elevation of satiety gut hormones in the blood, such as Glucagon-Like peptide 1 (GLP-1) and Peptide Tyrosine Tyrosine (PYY) and a reduction of ghrelin, an orexigenic hormone mainly produced by neuroendocrine cells mostly located in the gastric fundus. Recent physiological knowledge allows the design of bariatric procedures that aim at neuroendocrine changes instead of mechanical restriction and malabsorption.

"Santoro" have recently reported his long-term data regarding sleeve gastrectomy with transit bipartition (SG þ TB), which is a similar operation to duodenal switch (DS) but without complete exclusion of duodenum in order to minimize nutritional complications. The goal of this operation was to benefit the patients by counterbalancing the harmful effects of the modern diet. Without exclusions and with a simple surgical procedure, SG þ TB amplifies the nutritive stimulation of the distal gut whereas simultaneously diminishing the exposure of the proximal bowel to nutrients without completely deactivating duodenum and jejunum.

A Modification of Santoro's operation was first reported as a case report by Mui in 2013, then as a Case series on 68 patients by Greco and Tacchino in 2014 by performing a loop rather than Roux-en-Y bipartition reconstruction, which came to be known as (Single Anastomosis Sleeve Ileal "SASI") bypass.

That procedure has the advantage of maintaining the natural pathway through the duodenum where a small percentage of food passes, and is associated with minimal post-operative nutritional complications, and allows for full visualization of the biliary system during endoscopy. Moreover, it's suggested that the incidence of leakage and gastroesophageal reflux after sleeve gastrectomy is significantly reduced by the gastroileal bypass due to the decrease in stomach pouch pressure.

This study aims to evaluate SASI bypass as a mode of functional restrictive therapeutic option for morbidly obese patients, versus LSG.

Inclusion Criteria:

• Morbid Obesity (BMI ≥ 40 kg/m2) or ( ≥ 35 kg/m2 with associated co-morbidity e.g. type 2 diabetes, joint problems …)
• Age ≥ 18 and < 60
• Failure to achieve adequate and consistent weight loss for at least one year while being followed up by a dietitian.

Exclusion Criteria:

• Patients BMI < 35kg/m2
• Patients who managed to achieve consistent weight loss by diet control.
• Contra-indications to laparoscopic surgery e.g. intolerance to general anesthesia, coagulopathy or an associated condition that requires laparotomy.
• Contra-indications to gastrectomy e.g. gastric ulcer, hiatal hernia or gastro-esophageal reflux disease.
• Previous laparotomy or bariatric procedure.

Masking cannot be applied as both patient and surgeons must be fully informed and consenting regarding the procedure of choice, and the possible outcomes and complications