The single anastomosis sleeve ileal (SASI) bypass: A review of the current literature on outcomes and statistical results

Complication of Internal Herniation-related Bowel Obstruction Post-Single Anastomosis Sleeve Ileal (SASI) Bypass and Management: Series Case Sharing (Video Report)

BACKGROUND

Obesity is a global health concern associated with multiple comorbidities, and bariatric surgery remains one of the most effective interventions for sustained weight loss and metabolic improvement. The Single Anastomosis Sleeve Ileal (SASI) bypass is a novel procedure that offers a simplified surgical approach while maintaining efficacy. However, despite its advantages, SASI bypass carries a risk of postoperative complications, including internal herniation-related bowel obstruction-a rare but potentially life-threatening condition requiring prompt recognition and intervention.

METHOD

We report 3 cases of internal herniation following SASI bypass, 2 performed robotically and 1 laparoscopically. Despite uneventful surgical procedures, all 3 patients developed postoperative internal herniation, with symptom onset ranging from 1 week to 16 months after surgery. A comparative summary of their clinical presentations and outcomes is provided in the accompanying table. Due to timely diagnosis and prompt surgical intervention, all patients had favorable outcomes. In addition, we compiled and edited a surgical video from the third case to illustrate the operative management of this complication.

RESULTS

Computed tomography (CT) emerged as the gold standard for diagnosis, although immediate surgical exploration was necessary in cases of peritonitis or hemodynamic instability. Notably, 1 patient (Case 2) experienced rapid weight loss, a factor previously implicated as a potential risk for internal herniation. Petersen's defect was the most common herniation site in SASI bypass, resembling the pattern seen in One Anastomosis Gastric Bypass (OAGB) but differing from Roux-en-Y Gastric Bypass (RYGB), where multiple mesenteric defects increase the risk. While a longer biliopancreatic limb may predispose SASI and OAGB patients to herniation, consensus on routine defect closure remains lacking.

CONCLUSION

Internal herniation is a rare but serious complication of SASI bypass, with delayed diagnosis potentially leading to bowel ischemia or perforation. CT is essential for early detection, while timely surgical intervention is critical in symptomatic cases. The necessity of routine Petersen's defect closure remains debated, highlighting the need for further studies to determine the true incidence and optimal prevention strategies.

Outcomes of revisional surgery options after inadequate sleeve gastrectomy: A comprehensive network meta-analysis

BACKGROUND

Despite the success of sleeve gastrectomy (SG) in of weight loss and treatment of the medical problems associated with obesity, some concerns have arisen about the need for revisional surgeries after SG in some patients. This study aimed to present an updated and comprehensive comparison among the presently available revisional surgeries employed explicitly in cases of inadequate outcomes after SG, which is the most frequently performed bariatric surgery in contemporary practice.

METHODS

This network meta-analysis included studies that compared the outcomes of different revisional bariatric procedures after an inadequate outcome of SG.

RESULTS

Searching across the electronic databases yielded 31 eligible articles. Re-SG was associated with the highest rate of significant complications. Patients treated with single anastomosis duodenal-ileal bypass (SADI) had a significantly higher percentage of total weight loss (%TWL) than those treated with one anastomosis gastric bypass (OAGB) and Roux-en-Y gastric bypass (RYGB). The percentage of excess weight loss (%EWL) at the end of the follow-up period was significantly higher in patients in the SADI group compared to those in the RYGB group and the OAGB, and re-SG exhibited the least values compared to SADI, biliopancreatic diversion with duodenal switch (BPD/DS), and OAGB. Significantly lower rates of reflux worsening/de novo development were observed in the SADI group compared to the OAGB group and the re-SG group, which showed significantly higher rates than SADI and RYGB.

CONCLUSION

Our comprehensive network meta-analysis highlights SADI as a promising revisional option post-SG, demonstrating superior weight loss outcomes, lower significant complication rates, and a favorable impact on reflux compared to other procedures. While acknowledging the limitations of our study, these findings support the potential efficacy of SADI in addressing the challenges of inadequate weight loss after sleeve gastrectomy.

Effect of SASI procedure (Single Anastomosis Sleeve Ileal) on the symptoms of gastroesophageal reflux disease in bariatric patients - a review of the literature

The problem of gastroesophageal reflux disease among bariatric patients is constantly growing. While bariatric surgery is the most effective method of treating obesity and related diseases, not all surgical procedures lead to improvement or resolution of gastroesophageal reflux disease. The search for the "ideal" surgical procedure for this group of patients is ongoing. The relatively recently introduced SASI procedure seems to have a beneficial effect on GERD symptoms and may be an alternative anti-reflux procedure in obese patients. The presented paper is a review of the latest literature on the impact of SASI procedure on the symptoms of gastroesophageal reflux disease.

Mid-term outcomes after single anastomosis sleeve ileal (SASI) bypass in treatment of morbid obesity

BACKGROUND

According to several short-term studies, single-anastomosis sleeve ileal (SASI) bypass offers similar weight loss to Roux-en-Y Gastric Bypass (RYGB) with fewer complication and better comorbidity reduction/resolution. Long-term data on this operation is lacking in the literature. The purpose of this study was to analyze the outcomes of SASI bypass up to 4 years.

METHODS

This study is a retrospective cohort analysis of 366 patients with morbid obesity who underwent primary SASI bypass from January 2018 to February 2022.

RESULTS

The mean age and preoperative body mass index (BMI) were 41 years (range 22-71 years) and 43.9 ± 6.5 kg/m², respectively. Follow-up was available for 229 patients at 1-year (89%), 112 patients at 2-year (75%), 61 patients at 3-year (75%), and 35 patients at 4-year (71%). The intraoperative, short-term, and long-term complication rates were 0%, 2.5%, 4.6%, respectively. After 4 years, mean percentage excess weight loss (%EWL) was 93.3% and total weight loss (%TWL) was 41.2%. Remission of comorbidities was 93% for type 2 diabetes mellitus, 73% for hypertension, 83% for hyperlipidemia, 79% for sleep apnea, and 25% for gastroesophageal reflux disease (GERD). Biliary gastritis and ulcers are seldom. Eight patients developed de novo GERD symptoms requiring proton pump inhibitor treatment. None of the patients in our study had hypoalbuminemia or malabsorption that did not respond to increased protein intake and vitamin or mineral supplementation.

CONCLUSION

SASI bypass appears to be safe, and one of the most effective bariatric procedures regarding weight loss and obesity related comorbidities. The double-outlet created in this procedure seemingly minimizes nutritional complications.