Single Anastomosis Duodenal-Ileal (+ Sleeve) Bypass(SADI-S)

Single Anastomosis Duodenal-Ileal (+ Sleeve) Bypass

What is the SADI-S?

The Single Anastomosis Duodeno-Ileal (+ Sleeve) Bypass (SADI-S), also known as Stomach Intestinal Pylorus-Sparing (SIPS) surgery, or One Anastomosis Duodenal Switch (OADS), is considered a less-aggressive variation of the older style duodenal switch procedure. It is a surgical weight loss operation that combines two procedures – a sleeve gastrectomy, and a duodeno-ileal (bowel) bypass. The SADI-S can be performed either robotically or laparoscopically (keyhole surgery), leaving you with about five small incisions (cuts) in your abdomen.

How does the SADI-S help you?

  • This procedure combines both food restriction (due to the Sleeve Gastrectomy), and decreased calorie absorption (due to the Duodenal-Ileal Bypass).
  • The combination of restricted food intake as well as less ability to absorb all that you eat, results in significant weight loss.
  • Additionally, your satiety hormone LEPTIN will increase, and your hunger hormone GHRELIN will decrease, causing you to feel less hunger, and feel fuller for longer.

Advantages of the SADI-S

  • Combine benefits of both the sleeve gastrectomy and the bypass
  • Greater average weight loss than either sleeve gastrectomy or standard bypasses
  • Has only one join, instead of two
  • Greater metabolic effect than other procedures – rapid improvement of type 2 diabetes and other health conditions
  • Usually less ‘dumping’ and diarrhoea than other bypasses as the pylorus valve is preserved
  • Reduced risk of gastric ulcers
  • Reduced risk of internal hernia developing
  • Good weight loss maintenance
  • Good option as a revision procedure

Disadvantages of the SADI-S

  • More surgically complex than other weight-loss procedures
  • Higher complication rates and risk for mortality than other procedures
  • Increased risk of a leak due to two staples lines – one at the sleeve gastrectomy and the other at the bowel-to-bowel join 
  • May still experience ‘dumping’ if fats/sugars consumed.
  • More frequent bowel movements, flatulence and fatty stools
  • Greatest potential for malabsorption of vitamins and minerals – lifetime commitment to vitamin intake and annual blood tests is essential
  • Newer operation than others – research data still emerging
  • Not suitable for smokers

Risk and Complications of the SADI-S

Risks In the Short-Term

(common to most surgical procedures)

  • Bleeding during or after the operation
  • Damage to surrounding organs
  • Wound infections
  • Chest infections
  • Deep Vein Thrombosis (blood clots in your legs)
  • Pulmonary Emboli (blood clots in your lungs)
  • Leakage or bleeding at the stomach staple line, or at the bowel-to-bowel join 
  • Death (very rare)
  • Anaesthetic complications (see this section detailing these)

Risks In the Long-Term

  • Potential for adhesions or scar tissue formation within the abdomen (can occur after any abdominal procedure) and may require surgery to release
  • Potential for hernia formation at the site of the wound closure – this may require surgery to repair
  • Potential for internal hernia/bowel obstruction, where loops of bowel tangle/twist – this may require surgery to correct
  • Potential for anastomotic strictures where the bowel-to-bowel join over tightens during the healing process – this may require stretching by gastroscopy
  • Potential to develop bile reflux  – this may require medication or revision surgery
  • Potential to develop ulcers if patients smoke
  • Potential for development of nutritional deficiencies due to bowel involvement and malabsorptive feature of procedure – essential to maintain good diet + commit to vitamin/mineral supplementation + undergo annual blood tests to monitor/correct any deficiencies

How is the SADI-S performed?

Watch SADI-S Animation

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The information herein is not intended as medical advice. It should be considered as a reference only, or a starting point for further discussions with Dr Willingham and his team about weight loss surgery. Please be aware that results may vary from person to person