Outcomes Comparison Between Primary and Revisional Duodenal Switch in Patients with a BMI Greater than 55 kg/m2

<b>Background</b>: Revisional bariatric surgery for recurrent weight gain is becoming more common, though it carries higher risks and may be less effective than primary bariatric surgery. This study compares clinical outcomes between primary and revisional duodenal switch (DS) in patients with a body mass index (BMI) > 55 kg/m². <b>Methods</b>: A retrospective cohort study was conducted on 20 patients who underwent either primary or revisional duodenal switch (DS) surgeries, including biliopancreatic diversion with duodenal switch (BPDDS) and Single-Anastomosis Duodeno-Ileal Bypass with Sleeve Gastrectomy (SADI-s), between January 2015 and December 2023. Revisional DS was defined as the conversion from Sleeve Gastrectomy (SG) to either BPDDS (C-BPDDS) or SADI-S (C-SADI-S). Perioperative and postoperative variables were analyzed. A statistical analysis was performed using chi-square and McNemar tests for categorical variables and Student's <i>t</i>-test for continuous variables. A <i>p</i>-value of <0.05 was considered significant. <b>Results</b>: Eleven primary DS patients (six BPDDS, five SADI-s) and nine revisional DS patients (five C-BPDDS, four C-SADI-s) were included. The revisional group had a slightly higher preoperative BMI (57.56 ± 5.92 kg/m² vs. 55.93 kg/m² ± 6.91 kg/m²). Although operative times were shorter in the revisional group (153.20 ± 53.26 vs. 193.27 ± 46.79 min), the length of stay was longer (2.70 ± 1.25 vs. 2.18 ± 1.16 days). Primary DS patients experienced three minor late complications (dehydration, nephrolithiasis), whereas the revisional group had one major complication (internal hernia requiring reoperation). At the 12-month follow-up, both groups demonstrated similar outcomes in terms of percentage of total weight loss (%TWL) (primary DS: 25.25% ± 12.38 vs. revisional DS: 30.31% ± 10.79) and percentage of excess weight loss (%EWL) (primary DS: 48.41% ± 22.93 vs. revisional DS: 53.24% ± 14.48). <b>Conclusions</b>: Revisional DS was associated with shorter operation times and similar weight loss to primary DS. Additionally, it was accomplished safely and led to adequate and sustained weight loss in patients with a BMI greater than 55 kg/m².