The single anastomosis duodenal switch modifications: a review of the current literature on outcomes.

BACKGROUND: The single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) was designed in 2007 to reduce the side effects of biliopancreatic diversion with duodenal switch (BPD-DS) by replacing the Roux-en-Y construction with a single duodeno-ileal anastomosis and combining the common channel with the alimentary limb. Several variants using different channel lengths were published. The objective of this study was to identify the published cases of SADI-S and variants and assess the results regarding potential benefits on side effects and revisions.

METHODS: PubMed, ClinicalTrials.gov, and the databases of 3 relevant surgical journals were searched for any publication from 2007 to date.

RESULTS: In all, 19 studies were analyzed. After identifying overlaps, 1,041 patients among 9 institutions were identified: 304 with SADI-S, 667 with stomach intestinal pylorus sparing surgery, and 70 with single anastomosis duodenojejunal bypass with sleeve gastrectomy. There were no postoperative deaths and the early complication rate was 7.3% (range 1.6-14%). The mean operative time was 100.8 minutes (range 69.9-181.7 min). The mean 1-year percentage of excess weight loss (%EWL) was 78.7% (range 61.6-87%) and percentage of total weight loss (%TWL) was 36.8% (range 32.7-41.1%). Two studies reported a 2-year %TWL of 38.7% and a single study reported a 5-year %TWL of 37%. A total of 50% of patients had biological data at 1 year. One retrospective study found no difference between BPD-DS and SIPS for vitamin deficiency at 2 years, but there was less severe diarrhea and malnutrition after SIPS. The revision rate increased from 2% to 7% after SADI-S between 2- and 5-year follow-up.

CONCLUSION: There are still limited long-term data available for single anastomosis duodenal switch. In the absence of published prospective randomized trials, no evidence exists in favor of this variant of the BPD-DS despite a possible trend in less malabsorption side effects.