Patient BlogWeight Loss Surgery

Single Anastomosis Stomach-Ileal Bypass with Sleeve Gastrectomy (SASI-S) can be considered a safer modified version of the Single Anastomosis Duodeno-Ileal bypass with Sleeve gastrectomy (SADI-S).

The procedure combines the benefits of a sleeve gastrectomy (commonly known as gastric sleeve) and mini-gastric bypass while reducing the risk of nutritional problems in the long run.

Medical advancements in the weight-loss surgery field have given patients affected by obesity a wider range of bariatric procedures to help them lose weight and start a healthier life.

SASI-S is one of the latest bariatric procedures and we are going to give you an overview of how the procedure works, who it is for, and what you can expect after surgery.

What is Single Anastomosis Stomach–Ileal Bypass with Sleeve Gastrectomy, or SASI-S?

Single Anastomosis Stomach–Ileal Bypass with Sleeve Gastrectomy, or SASI-S, is a weight-loss procedure that aims to reduce the amount of food intake and absorption by modifying parts of the digestive tract.

The surgery is performed laparoscopically: the surgeon will create a few small incisions in your abdomen to carry out the procedure. Laparoscopic procedures are less invasive, require a shorter recovery time, and leave little to no scarring.

SASI-S: How is the procedure performed?

SASI-S is performed under general anaesthesia, so you will sleep throughout the procedure, which typically lasts around 1 hour. It can be performed as a single-stage procedure or as a modification of an already created gastric sleeve.

The SASI procedure can be considered an evolution of the Omega loop or mini-gastric bypass. First, the surgeon will perform a sleeve gastrectomy. Around 75% of the stomach is removed, leaving a banana-shaped pouch in place. The reduction of the stomach will limit the amount of food intake as well as reduce the level of the hunger hormone (ghrelin).

Then, the surgeon will perform the mini-gastric bypass, which involves joining the bottom part of the stomach (antrum) to the lower part of the small bowel (ileum). This way, half of the food that is ingested bypasses the small intestine, reducing the absorption of fats, sugar, and calories. The new stomach is then connected to the small intestine. A leak test may be performed at the end of the operation.

The surgeon will remove the instruments and close the incisions with stitches.

Who is Single Anastomosis Stomach–Ileal Bypass with Sleeve Gastrectomy for?

SASI-S is a procedure designed to help obese or severly obese individuals tackle their weight-related problems.

As for all bariatric procedures, SASI-S is suitable for:

  • Patients whose BMI is greater than 40 (if you’re unsure of what BMI is, you can calculate yours here);
  • Patients whose BMI is between 35 and 40 and have one or more health problems associated with obesity, such as: high blood pressure, sleep apnea, type 2 diabetes, impaired glucose tolerance, hyperlipidemia, or heart disease.
  • Patients whose BMI is greater than 30 and have an obesity-related illness might also be suitable.

These are general eligibility guidelines. We will evaluate each patient on a case-to-case basis based on their medical history, current health, and needs. Feel free to get in touch with us anytime. Our patient coordinators will have a first consultation with you to assess if SASI-S is the right procedure for you.

How do you prepare for SASI surgery?

During your consultation with our patient coordinators, you will be asked to provide a list of all medications, vitamins or supplements you are currently taking. There might be restrictions in the medicine you can take before and after surgery, so make sure you give us a complete overview.

Our patient coordinators will also ask about your medical history and current illnesses you might have. If you have diabetes, you might need to take or adjust your medication before and after surgery.

You should stop smoking at least two weeks before the operation.

What can you expect after SASI surgery?

You are typically discharged from our clinic 24 hours after having undergone SASI surgery. You will receive a thorough post-surgery diet and exercise plan for you to follow in the weeks and months after the procedure. This is a crucial part of your weight-loss journey! These guidelines will help you enter a new phase in your life – supporting a balanced and healthier lifestyle. Your commitment is everything and it will pay off!

Patients typically go back to their daily routine activities after 5 to 7 days but you will be encouraged to move around 3-4 hours after the operation.

For the first two weeks after a SASI procedure, you might experience fatigue. This is normal, as you are decreasing your calorie intake with a liquid diet. You will notice that your energy levels will increase rapidly after this period of time as you slowly transition to a soft diet.

In terms of exercise, you will be recommended to do some light exercise in the weeks following surgery while slowly transitioning into more intense workouts around two months after surgery.

What are the benefits of SASI-S?

SASI-S has a series of benefits compared to other bariatric procedures or SADI-S, including:

  • Greater weight loss compared to the gastric sleeve alone, according to recent data.
  • Lower risk of weight regain in the medium term compared to the gastric sleeve.
  • Lower risks of nutritional problems or deficiencies in the long term.
  • Positive impact on Type 2 diabetes, high cholesterol, and lipids.
  • Reduction of reflux as pressure on the stomach is reduced.
  • Reversible procedure: it can be reversed to a gastric sleeve.
  • Lower risk of internal hernia.
  • Lower risk of a leak along the staples compared to SADI-S.
Would you like to learn more about the procedure?
Contact us and we will clear your doubts

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