The rise of the duodenal switch: a narrative review

Introduction

Background

In the current era of metabolic and bariatric surgery (MBS), there are a variety of procedures available to address the chronic burden of obesity. The biliopancreatic diversion with duodenal switch (BPD-DS) is a relatively complex bariatric procedure that has evolved significantly over the years. Commonly known as the duodenal switch (DS), this bariatric procedure incorporates both restrictive and malabsorptive components to reduce caloric intake and change the metabolism of patients with obesity (1). The introduction of this procedure can be traced back to Scopinaro et al., who performed the first BPD-DS in 1979 (1,2). The initial surgical technique was refined over the years to include a partial gastrectomy performed along the greater curvature, known as a sleeve gastrectomy (SG). Further modifications were progressively made to address the procedure-specific complications and improve patient outcomes. Indeed, in an attempt to reduce the rates of marginal ulceration (MU), dumping syndrome, and hypoabsorptive complications, Hess et al. modified the DS in 1998 and suggested anastomosing the ileum to the duodenum and measuring the entire small bowel and adjusting the lengths of the alimentary limb and common channel (CC) accordingly, which led to the modern form of the DS (3). The BPD-DS procedure was followed by the development of the single anastomosis duodeno-ileostomy with sleeve (SADI-S) (4). This newer surgical approach has been associated with similar outcomes compared to the BPD-DS, while minimizing the post-operative complications associated with a Roux-en-Y configuration (4).

Rationale and knowledge gap

Despite its proven effectiveness, there remains some reluctance in the adoption of the DS by bariatric surgeons. A major hurdle is the technical complexity of the procedure as well as the learning curve required to perform the DS safely and efficiently (5). Nevertheless, both the BPD-DS and the SADI-S have gained popularity recently, with the American Society for Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity (IFSO) endorsing the SADI-S in 2020 and 2018 respectively (6). SG and Roux-en-Y gastric bypass (RYGB) are still the most commonly performed MBS procedures in the United States, however, the number of performed DS has doubled from 0.9% to 2.1% of the total MBS surgeries in the last decade (7).

Objective

Thus, the aim of this review is to clearly describe the DS procedures while reporting the most recent published literature on indications, surgical techniques, and surgical outcomes of primary and revisional BPD-DS and SADI-S. We present this article in accordance with the Narrative Review reporting checklist (available at https://ales.amegroups.com/article/view/10.21037/ales-24-9/rc).

Methods

An extensive literature review (LR) was coordinated and performed by the authors of this manuscript. The initial LR was conducted in three phases: identifying relevant research questions and keywords, performing the LR, and reporting research findings. The different tasks were coordinated by all the involved authors, which included drafting an LR protocol, describing inclusion and exclusion criteria, selecting an appropriate search strategy, choosing search engines, ensuring selected quality, and extracting the data for final manuscript writing. Using selected databases such as PubMed, ScienceDirect, and Springer Link, relevant articles were chosen from inception to 2023 and were filtered according to our keywords: ‘obesity’, ‘bariatric surgery’, ‘metabolic surgery’, ‘duodenal switch’, ‘BPD-DS’, ‘SADI-S’, ‘robotic-assisted surgery’, ‘surgical outcomes’, ‘weight loss outcomes’, ‘postoperative complications’, ‘anastomotic leak’, ‘bile reflux’, ‘marginal ulcers’, and ‘malabsorption’. Final article inclusion was approved by the corresponding author, who implemented expert opinion to synthesize the collective information and thoroughly edit the manuscript draft (Table 1 and Table S1).

Indications and patient selection criteria

In the realm of bariatric surgery, procedures such as the BPD-DS, SADI-S, and even revisional DS, are typically reserved for patients with an obesity class IV [body mass index (BMI) >50 kg/m²] (8,9). These advanced surgical options, often performed in specialized, well-trained centers, have seen limited adoption partly due to the steep learning curve and concerns over potential complications (5). However, a recent report by Clapp et al., demonstrated a comparable safety profile for the DS compared to other established MBS procedures on the short-, mid-, and long-term (10). This emerging evidence supports a broader application of the DS, suggesting it should be offered more confidently to suitable patients (10,11).

Preoperative assessment and patient optimization

Patients eligible for DS must undergo a thorough preoperative evaluation conducted by a multidisciplinary team. This team comprises a bariatric surgeon, an endocrinologist, a psychologist, a registered dietitian, and other specialized healthcare providers (12,13). Apart from a comprehensive medical history and physical examination, a range of metabolic tests is essential to identify and address obesity-related medical conditions. Also, it is crucial to assess the patient’s overall nutritional status through tests for serum vitamins, iron studies, serum albumin, and prealbumin levels. An esophagogastroduodenoscopy (EGD) is typically performed preoperatively as part of the investigation for concomitant esophageal or gastric disease. Lastly, it is also recommended to conduct psychological and compliance assessments prior to DS (12,13).

Surgical techniques

The original surgical technique for the BPD-DS was modified and refined multiple times to decrease postoperative complication rates while maintaining its efficacy (14). Sánchez-Pernaute and Torres later proposed the SADI-S in 2007 as a simplified alternative to the BPD-DS (4,15). This modified technique served as a replacement for the traditional Roux-en-Y with a single loop duodeno-ileostomy by eliminating the Roux limb (16). An important aspect of the BPD-DS and SADI-S is preservation of the pylorus, which allows for regulated gastric emptying and minimizes the risk of some complications such as MU and dumping syndrome (17).

SADI-S

The initial step of the SADI-S procedure is the opening of the gastrocolic ligament, followed by the take-down of the vascular attachments between the stomach and the greater curvature. This dissection progresses toward the fundus until complete exposure of the left diaphragmatic crus is achieved. Subsequently, the distal dissection is carried out caudally, extending 3–4 cm beyond the pylorus. Identification of the gastroduodenal artery posterior to the stomach constitutes the landmark for proper duodenal dissection. Depending on the surgeon’s preference, the right gastric artery can be ligated and transected to allow for easier translocation of the duodenum. Duodenal transection is generally deferred until ensuring that the bowel can reach, and the anastomosis can be performed without tension. The SG is then created using a 50–60 Fr bougie. Once the sleeve is performed, the ileocecal valve should be identified and followed 300 cm proximally from its origin. Following duodenal transection, the selected loop is anchored to the proximal sectioned duodenum, while making sure to preserve proper orientation. A completely stapled, partially stapled or hand sewn manual end-to-side antecolic duodeno-ileal anastomosis is established. Most literature reports hand-sewn double-layered anastomoses. The anastomosis is usually tested intraoperatively for leaks with liquid contrast or air insufflation. Once the patency of the anastomosis is ensured, the remnant stomach is removed, and the incision sites are closed. In recent years, the common limb length has been lengthened to 300 cm to minimize risks of malnutrition while maintaining the proven efficacy of the procedure (16,18,19). The Peterson’s defect is closed (when possible). There is a debate among MBS surgeons on the importance of closing the Peterson defect following the procedure, with some surgeons closing the window whenever possible (14,20,21).

BPD-DS

Our BPD-DS technique follows the same steps of performing the SADI-S detailed above. Once that part is concluded, and to perform the BPD-DS, a transection of the biliopancreatic limb just proximal to the duodeno-ileostomy is required. The creation of the ileo-ileostomy between the transected biliopancreatic limb and the CC will then be performed lower on the CC limb. The alimentary limb is measured accurately, and the small bowel is run for from the duodeno-ileostomy and down approximately 150 cm. The ileo-ileostomy is then created at this mark on the alimentary limb in a stapled or hand-sewn fashion, and the mesenteric defect is closed to avoid internal hernia occurrence.

Postoperative management

In the immediate postoperative course, patients who undergo DS are placed on venous thromboembolism (VTE) prevention regimen which includes early ambulation, compression devices, and administration of low molecular weight or unfractionated heparin. Patients are typically started on a clear liquid diet followed by a progression to a low-fat, full-liquid diet. Patients are then required to adhere to prescribed protein supplements, a vitamin regimen, and gradual progression in food consistency. Outpatient post-operative visits occur after discharge with additional repeated checkups thereafter (22).

Postoperative complications after DS

In its early adoption phase, metabolic and bariatric surgeons were reluctant to offer the DS essentially due to the fear of postoperative complications which was partly explained by the learning curve of this procedure (5). Over the years, both the BPD-DS and SADI-S have evolved to become safe and efficient MBS procedures and when performed in well-trained centers have been associated with a comparable safety profile to other traditional bariatric surgeries. In a recent meta-analysis by Nakanishi et al., the pooled rates of early and late complications following DS varied between 7.5–10.5% and 13.9–26.5%, respectively (23). These surgical complications mainly include staple line/anastomotic leaks, MU, internal hernias, and long-term malnutrition (24). As these complications constitute major indications for revision/conversion surgery after primary DS, it is important to properly counsel and follow-up with patients to achieve optimal outcomes. Also, mortality rates associated with these procedures were approximately 1% (25).

Multiple short-term studies comparing postoperative complication rates between BPD-DS and SADI-S demonstrated an equivalent safety profile without any significant differences (26,27). On the other hand, long-term reports have demonstrated that BPD-DS might be associated with increased morbidity, primarily due to the higher incidence of small bowel obstruction, hernias, and protein deficiency (28). Nevertheless, both of these procedures remain relatively safe with low morbidity and mortality rates.

Staple line and anastomotic leaks

Staple line and anastomotic leaks are concerning complications of DS. Anastomotic leak can occur either at the duodeno-ileostomy or ileo-ileostomy for the BPD-DS, and at the duodeno-ileostomy for the SADI-S. Staple line leak can occur at the SG for both procedures. Reported incidence rates range from 0.5-6% for the BPD-DS and from 0.1% to 5.6% for the SADI-S (9). Although not clinically significant, this difference in incidence between both procedures is expected with the SADI-S having one less anastomosis and source of leak. Compared to other commonly performed procedures, the rates of leak after DS are higher than staple line leaks after SG (1.5–3%) and comparable to those after RYGB (1–5.1%) (9,29,30). It is crucial to diagnosis anastomotic leak early to avoid potential serious morbidity, and management strategy should be individualized according to the characteristics of the leak and the clinical status of the patient.

MU

MU remain an important complication following MBS. A crucial aspect of the pylorus-preserving DS is the lower rate of associated MU compared to procedures such as the RYGB. Recent reports have shown that MU are reported in less than 1% of patients undergoing DS, while they can occur in upwards of 25% after RYGB (31,32). This difference is mainly explained by the preservation of the duodenum in the DS. The preserved Brunner’s glands confer a major buffering role by secreting a mucin-rich alkaline fluid that protects the mucosa from the acidic gastric secretions, thus decreasing the risk of mucosal damage and consequent ulceration (33). These glands are excluded in the RYGB where acidic secretions are directly in contact with the gastrojejunostomy. Given that MUs are independent predictors of higher mortality and revision surgery, bariatric surgeons should be aware of the lower rates associated with DS during initial procedure selection. Regarding the management of MU, most cases resolve with PPI use, however a small minority of cases might eventually require revisional surgery for efficient ulcer treatment.

Internal hernias

Multiple reports have described a lower rate of internal hernias after SADI-S (1.5%) compared to BPD-DS (8%). A valid explanation to these lower rates is the creation of a single anastomosis during the SADI-S compared to two in the BPD-DS (34). Similarly, the same reasoning can be applied to explain the lower incidence of internal hernias compared to the RYGB (8.6%) which requires two anastomoses and multiple mesenteric openings (35).

Bile reflux

The anatomical configuration of the BPD-DS confers a significant advantage compared to the SADI-S which is the absence of postoperative bile reflux. Indeed, bile reflux after SADI-S remains a concern of the procedure which may hinder its acceptance in common bariatric practice. Although bile reflux is uncommonly reported after SADI-S (36), it can lead to significant symptoms for the patients. The retrograde passage of alkaline duodenal contents into the stomach is thought to be caused by the alteration of gastroduodenal anatomy (secondary duodenogastric reflux) (37). Also, the pyloric denervation resulting from excessive duodenal dissection might contribute to the pyloric sphincter incompetence, which also increases risk of bile reflux. A recent meta-analysis clarified the issue of bile reflux post-SADI-S by demonstrating an event rate of only 0.016 and a pooled incidence of 1.23% across seven different studies (36). The BPD-DS, on the other hand, has been deemed as the ideal procedure to manage bile reflux, and revision to a BPD-DS after a SADI-S complicated by bile reflux is the optimal management.

Nutritional deficiencies and protein-calorie malnutrition

Long-term malabsorptive symptoms, nutritional deficiencies, and protein-calorie malnutrition are also relatively common complications after DS. The length of the CC in the BPD-DS and SADI-S is speculated to play an important role in the development of these hypoabsorptive complications (38). Multiple SADI-S studies comparing CC length demonstrated a lower rate of malabsorption associated with 300 cm CC compared to shorter CC of 200–250 cm. Overall, the rates of malabsorption after SADI-S seem to be lower compared to the BPD-DS (23).

Nutritional and micronutrient deficiencies, particularly vitamin D, K, and zinc deficiencies have been reported after BPD-DS due to the bypass of the duodenum and jejunum which are essential for vitamin absorption. One study reported vitamin D deficiency in 89% of patients, vitamin K deficiency in 65%, and zinc deficiency in 65%, with one mortality caused by severe malnutrition 8 years postoperatively (39). A significant percentage of patients experience hypocalcemia and secondary hyperparathyroidism postoperatively, possibly due to vitamin D deficiencies (39). Another study also found that 69% of patients had long-term vitamin A deficiency, and that the incidence of vitamin A, D, and K deficiencies increased with time post-surgery. Lastly, there is an increased risk of thiamine deficiency in the early months post-DS (40). The SADI-S configuration aimed to mitigate some of the risk of nutritional deficiencies associated with BPD-DS.

After DS, patients often fail to adhere to the required protein intake and sometimes shift towards fatty foods which exacerbates the risk of protein-calorie and macronutrient deficiencies (40). Hypoalbuminemia was reported in 3–5% of patients after DS and protein malnutrition requiring reoperation occurs in 4–5% of cases (39). A shorter CC has been associated with higher risk of protein malnutrition due to the limited mixing of pancreatic secretions with proteins, consequently affecting the digestion and absorption of proteins. Hair loss is frequently the initial sign of protein deficiency. In more severe cases, deficiencies can result in edema, anemia, and hypoalbuminemia (40).

Patient education and continuous long-term supplementation following DS are crucial. In cases where deficiencies persist despite supplementation, successful resolution of malabsorptive complications has been achieved through reoperation and lengthening of the common limb.

Weight loss outcomes

A main advantage of the DS compared to other bariatric procedures is the superior weight loss outcomes in the short- and long-term. Despite RYGB and SG being the dominant bariatric procedures, recent reports have demonstrated a high rate of insufficient weight loss (IWL) following these procedures, deemed as ‘surgical failure’. Indeed, IWL rates, defined as % excess weight loss (EWL) <50%, can reach up to 35% after RYGB and 25% after SG. On the other hand, the DS shows a higher likelihood of successful weight loss on the short and long-term (41). A 2020 retrospective study showed that DS was associated with long-term weight loss failure in only 17.4% of patients (38). Also, DS seems to be associated with lower rates of long-term weight recurrence compared to RYGB and SG, highlighting the sustained effect of weight loss after DS (42,43).

The BPD-DS has the highest amount of weight loss. In the short-term, the %EWL can reach 78.7% (39). A systematic review of fourteen studies found that at 3 months post-operative the SADI-S resulted in a mean total weight loss ranging from 11.3% to 17.3%, mean excess body weight loss from 21.8% to 40.2%, and mean excess BMI loss from 9.4% to 31.1% (44). The SADI-S procedure was shown to induce similar percentage of EWL and excess BMI loss 6 months post-operation as the BPD-DS.

Similar to RYGB and SG trends, the greatest weight loss is achieved within the first 24 months post-DS, after which the weight loss curve plateaus. However, weight loss after DS is typically sustained on the long-term, with very low rates of weight recurrence (45). A recent study by Sethi et al. demonstrated a sustained long-term EWL of 67.9% in patients at 10–15 years post-operative (39). Similarly, other retrospective studies supported the EWL of 71% that was maintained up to 20 years after surgery (46). Lastly, while there was no difference in EWL between SADI-S and BPD-DS at 2 years post-operative, BPD-DS had a more favorable outcome than SADI-S at 1- and 2-year post-operative when measuring excess BMI loss (23).

Obesity-related medical conditions resolution

Among bariatric surgical procedures, BPD-DS has been shown to have the highest resolution rate for type 2 diabetes mellitus (T2DM). Multiple studies have shown that T2DM remission rates at 1- and 2-year post-BPD-DS can reach up to 90% and 85% respectively compared to 50–60% T2DM remission rate in RYGB patients (47,48). Similarly, hypertension, hyperlipidemia, and obstructive sleep apnea (OSA) resolution rates within one year of BPD-DS exceed 90%, with one study showing that every patient with OSA was cured within 8 months of surgery (49). In a previous study, 44.7% of patients with gastroesophageal reflux disease (GERD) experienced complete resolution following BPD-DS. The study also found that patients with preoperative T2DM were less likely [odds ratio (OR) =0.248] to experience GERD resolution than those without (50). In patients with BMI >50 kg/m², BPD-DS is more effective at resolving hypertension, hyperlipidemia, and OSA than RYGB and SG, although no significant difference was found in T2DM resolution between the three procedures (45).

SADI-S also demonstrated a significant post-surgical resolution of medical conditions. Two separate systematic reviews reported T2DM resolution in 72.6% and 74.1% of patients, respectively. Dyslipidemia resolution was observed in 77.2% of cases post-surgery, although another systematic review reported resolution or improvement in only 68.3% of cases. Hypertension was either resolved or improved in greater than 90% of patients as well. OSA and GERD both had resolution/improvement rates surpassing 75% (44,51). At 6 years post-operative, 77% of T2DM cases were resolved, along with 66.4% of hyperlipidemia, 60% of hypertension, 53.7% of GERD, and 52.9% of OSA cases (38). No significant difference in the remission rates of dyslipidemia, hypertension, diabetes mellitus, or OSA between SADI-S and BPD-DS were found (23).

DS as a revisional procedure

Revisional MBS has become the third most commonly performed bariatric procedure in the United States (7). While RYGB is still the most performed revisional procedure, there has been a recent increase in revisional DS procedures (7). As a revisional procedure, BPD-DS is mostly indicated as a second-stage surgery after primary SG for weight-related indications (52). However, some studies have also described the outcomes of revisions to BPD-DS after a primary adjustable gastric band (AGB) or RYGB. Revisions/conversions to SADI-S have also been described but remain scarce.

SG is currently the most dominant bariatric procedure worldwide (7). Unfortunately, some patients might eventually require revisional surgery in the long-term due to IWL, severe reflux, or other surgery-specific complications. The rates of revisional procedures after SG were reported to reach up to 12.2% at 10 years’ follow-up (53). Revisional options include RYGB, SADI-S, and BPD-DS. RYGB remains the preferred revisional option compared to DS for patients experiencing weight recurrence with documented reflux after SG (52). However, DS presents a valid revisional option for weight management after primary SG complicated by weight recurrence or IWL. Revisional DS is associated with the greatest weight loss compared to RYGB or other bariatric procedures while also having a similar safety profile with comparable morbidity and mortality (54). A recent analysis of the national MBSAQIP database demonstrated no significant differences in short-term mortality between SADI-S, BPD-DS, and RYGB as revisional procedures after primary SG. However, SADI-S and BPD-DS patients had longer operative time and higher leak rates which might be correlated with higher long-term complications and requires further investigation (53).

Primary RYGB and AGB conversions to DS are relatively less performed and the published literature on this topic remains scarce. AGBs are commonly revised or converted to RYGB due to device-related complications such as dysphagia, erosion, slippage, and infections (55). However, a recent retrospective study evaluating DS as a revisional bariatric option demonstrated that DS conversions are an effective salvage procedure for IWL and/or weight recurrence after primary AGB, SG, and RYGB and that it is also safe with low readmission, reoperation, and mortality rates (54). Despite these promising results, a recent expert consensus concluded that the applicability of BPD-DS as a revisional procedure for failed RYGB is still limited by the technical difficulty of this revision (52).

The rise of the DS

The recent surge in the popularity of DS procedures in bariatric surgery is a notable trend, marked by its increasing use for the treatment of obesity. While it is still primarily being used as a revisional option for SG, some surgeons adopted the DS as a primary procedure. There is a growing interest in this technique among the surgical community. This interest, however, has not uniformly translated into widespread adoption due to various factors, including a perceived high complication rate, lack of training, and technical challenges (5).

A significant development in the realm of DS procedures is the role of robotic platforms. Robotic-assisted surgery rates are notably higher in BPD-DS (34.9%) and SADI-S (30.2%) groups compared to the RYGB (21.5%) (53). This increased use of robotic assistance has broadened the adoption of DS by overcoming some of the technical hurdles presented by laparoscopy.

Despite technological advancements and growing interest, several barriers to the adoption of DS remain. Among surgeons, 43.5% cited a high long-term complication rate as a deterrent, while 38.1% pointed to a lack of training, and 31.5% noted that the procedure is seldom demanded by patients (5). Additionally, surgeons intending to familiarize themselves with DS often face challenges due to the procedure’s technical complexity and the need for specialized training (53). More importantly, there has not been widespread coverage by third-party payors. Until this happens, there is unlikely to be an increase in DS procedures. The ASMBS’s recent endorsement of this procedure has enhanced its practice by providing strong evidence regarding the favorable safety profile and superior efficacy compared to other bariatric procedures.

Conclusions

The DS, whether BPD-DS or SADI-S, is becoming more commonly performed. Recent short and long-term reports have validated the superior aspects of this procedure compared to traditional bariatric surgeries. The DS is associated with higher and sustained weight loss outcomes while also demonstrating a favorable safety profile with low morbidity and mortality. Further long-term comparative studies are needed to support these findings and reinforce the DS’s role amongst bariatric surgeons.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the Narrative Review reporting checklist. Available at https://ales.amegroups.com/article/view/10.21037/ales-24-9/rc

Peer Review File: Available at https://ales.amegroups.com/article/view/10.21037/ales-24-9/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://ales.amegroups.com/article/view/10.21037/ales-24-9/coif). O.M.G. serves as an unpaid editorial board member of Annals of Laparoscopic and Endoscopic Surgery from September 2023 to August 2025. B.C. is a consultant for Moon Surgical and Medtronic, and reports receiving meal stipend from Ethicon. The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Scopinaro N, Gianetta E, Civalleri D, et al. Bilio-pancreatic bypass for obesity: II. Initial experience in man. Br J Surg 1979;66:618-20. [Crossref] [PubMed]
2. Scopinaro N, Adami GF, Marinari GM, et al. Biliopancreatic diversion. World J Surg 1998;22:936-46. [Crossref] [PubMed]
3. Hess DS, Hess DW. Biliopancreatic diversion with a duodenal switch. Obes Surg 1998;8:267-82. [Crossref] [PubMed]
4. Sánchez-Pernaute A, Rubio Herrera MA, Pérez-Aguirre E, et al. Proximal duodenal-ileal end-to-side bypass with sleeve gastrectomy: proposed technique. Obes Surg 2007;17:1614-8. [Crossref] [PubMed]
5. Clapp B, Badaoui JN, Gamez JA, et al. Reluctance in duodenal switch adoption: an international survey among bariatric surgeons. Surg Obes Relat Dis 2021;17:1760-5. [Crossref] [PubMed]
6. Kallies K, Rogers AMAmerican Society for Metabolic and Bariatric Surgery Clinical Issues Committee. American Society for Metabolic and Bariatric Surgery updated statement on single-anastomosis duodenal switch. Surg Obes Relat Dis 2020;16:825-30. [Crossref] [PubMed]
7. Clapp B, Ponce J, DeMaria E, et al. American Society for Metabolic and Bariatric Surgery 2020 estimate of metabolic and bariatric procedures performed in the United States. Surg Obes Relat Dis 2022;18:1134-40. [Crossref] [PubMed]
8. Gadde KM, Martin CK, Berthoud HR, et al. Obesity: Pathophysiology and Management. J Am Coll Cardiol 2018;71:69-84. [Crossref] [PubMed]
9. Pennestrì F, Sessa L, Prioli F, et al. Single anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S): experience from a high-bariatric volume center. Langenbecks Arch Surg 2022;407:1851-62. [Crossref] [PubMed]
10. Clapp B, Mehta K, Corbett J, et al. Duodenal switch versus Roux-en-Y gastric bypass: a perioperative risk comparative analysis of the MBSAQIP Database (2015-2019). Surg Obes Relat Dis 2022;18:253-9. [Crossref] [PubMed]
11. Nakanishi H, Abi Mosleh K, Al-Kordi M, et al. Evaluation of Long-Term Nutrition Outcomes After Duodenal Switch: A Systematic Review and Meta-Analysis. Am Surg 2024;90:399-410. [Crossref] [PubMed]
12. Schlottmann F, Nayyar A, Herbella FAM, et al. Preoperative Evaluation in Bariatric Surgery. J Laparoendosc Adv Surg Tech A 2018;28:925-9. [Crossref] [PubMed]
13. Mechanick JI, Youdim A, Jones DB, et al. Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery. Obesity (Silver Spring) 2013;21:S1-27. [Crossref] [PubMed]
14. Afaneh C, Pomp A. Duodenal Switch: Technique and Outcomes. In: Reavis KM, Barrett AM, Kroh MD. editors. The SAGES Manual of Bariatric Surgery. Cham: Springer International Publishing; 2018:327-38.
15. Andalib A, Safar A, Bouchard P, et al. Single Anastomosis Duodenal Switch versus Classic Duodenal Switch: Long-term Outcomes from a Prospective Comparative Cohort Study. Obes Surg 2023;33:3951-61. [Crossref] [PubMed]
16. Cottam D, Cottam S, Surve A. Single-Anastomosis Duodenal Ileostomy with Sleeve Gastrectomy "Continued Innovation of the Duodenal Switch". Surg Clin North Am 2021;101:189-98. [Crossref] [PubMed]
17. Halawani HM, Antanavicius G, Bonanni F. How to Switch to the Switch: Implementation of Biliopancreatic Diversion with Duodenal Switch into Practice. Obes Surg 2017;27:2506-9. [Crossref] [PubMed]
18. Gebellí JP, Lazzara C, de Gordejuela AGR, et al. Duodenal Switch vs. Single-Anastomosis Duodenal Switch (SADI-S) for the Treatment of Grade IV Obesity: 5-Year Outcomes of a Multicenter Prospective Cohort Comparative Study. Obes Surg 2022;32:3839-46. [Crossref] [PubMed]
19. Abi Mosleh K, Belluzzi A, Jawhar N, et al. Single Anastomosis Duodenoileostomy with Sleeve: A Comprehensive Review of Anatomy, Surgical Technique, and Outcomes. Curr Obes Rep 2024;13:121-31. [Crossref] [PubMed]
20. Roslin M, Tugertimur B, Zarabi S, et al. Is There a Better Design for a Bariatric Procedure? The Case for a Single Anastomosis Duodenal Switch. Obes Surg 2018;28:4077-86. [Crossref] [PubMed]
21. Biertho L, Lebel S, Marceau S, et al. Biliopancreatic Diversion with Duodenal Switch: Surgical Technique and Perioperative Care. Surg Clin North Am 2016;96:815-26. [Crossref] [PubMed]
22. Bal BS, Finelli FC, Shope TR, et al. Nutritional deficiencies after bariatric surgery. Nat Rev Endocrinol 2012;8:544-56. [Crossref] [PubMed]
23. Nakanishi H, Matar RH, Vahibe A, et al. Single Versus Double Anastomosis Duodenal Switch in the Management of Obesity: A Meta-analysis and Systematic Review. Surg Laparosc Endosc Percutan Tech 2022;32:595-605. [Crossref] [PubMed]
24. Skogar ML, Sundbom M. Early complications, long-term adverse events, and quality of life after duodenal switch and gastric bypass in a matched national cohort. Surg Obes Relat Dis 2020;16:614-9. [Crossref] [PubMed]
25. Marceau P, Biron S, Hould FS, et al. Duodenal switch: long-term results. Obes Surg 2007;17:1421-30. [Crossref] [PubMed]
26. Moon RC, Kirkpatrick V, Gaskins L, et al. Safety and effectiveness of single- versus double-anastomosis duodenal switch at a single institution. Surg Obes Relat Dis 2019;15:245-52. [Crossref] [PubMed]
27. Pereira AM, Guimarães M, Pereira SS, et al. Single and dual anastomosis duodenal switch for obesity treatment: a single-center experience. Surg Obes Relat Dis 2021;17:12-9. [Crossref] [PubMed]
28. Yashkov Y, Bordan N, Torres A, et al. SADI-S 250 vs Roux-en-Y Duodenal Switch (RY-DS): Results of 5-Year Observational Study. Obes Surg 2021;31:570-9. [Crossref] [PubMed]
29. Bashah M, Khidir N, El-Matbouly M. Management of leak after sleeve gastrectomy: outcomes of 73 cases, treatment algorithm and predictors of resolution. Obes Surg 2020;30:515-20. [Crossref] [PubMed]
30. Mocanu V, Dang J, Ladak F, et al. Predictors and outcomes of leak after Roux-en-Y gastric bypass: an analysis of the MBSAQIP data registry. Surg Obes Relat Dis 2019;15:396-403. [Crossref] [PubMed]
31. Bekhali Z, Sundbom M. Low Risk for Marginal Ulcers in Duodenal Switch and Gastric Bypass in a Well-Defined Cohort of 472 Patients. Obes Surg 2020;30:4422-7. [Crossref] [PubMed]
32. Wynn M, Tecson KM, Provost D. Marginal ulcers and associated risk factors after Roux-en-Y gastric bypass. Proc (Bayl Univ Med Cent) 2023;36:171-7. [Crossref] [PubMed]
33. Salame M, Teixeira AF, Lind R, et al. Marginal Ulcer and Dumping Syndrome in Patients after Duodenal Switch: A Multi-Centered Study. J Clin Med 2023;12:5600. [Crossref] [PubMed]
34. Pokala B, Giannopoulos S, Stefanidis D. Prevention and management of internal hernias after bariatric surgery: an expert review. Minim Invasive Surg 2022;6:23. [Crossref]
35. Morgan H, Chastanet R, Lucha PA Jr. Internal hernia after laparoscopic gastric bypass surgery: a case report and literature review. Postgrad Med 2008;120:E01-5. [Crossref] [PubMed]
36. Portela R, Marrerro K, Vahibe A, et al. Bile Reflux After Single Anastomosis Duodenal-Ileal Bypass with Sleeve (SADI-S): a Meta-analysis of 2,029 Patients. Obes Surg 2022;32:1516-22. [Crossref] [PubMed]
37. Mabrut JY, Collard JM, Baulieux J. Duodenogastric and gastroesophageal bile reflux. J Chir (Paris) 2006;143:355-65. [Crossref] [PubMed]
38. Surve A, Cottam D, Medlin W, et al. Long-term outcomes of primary single-anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S). Surg Obes Relat Dis 2020;16:1638-46. [Crossref] [PubMed]
39. Sethi M, Chau E, Youn A, et al. Long-term outcomes after biliopancreatic diversion with and without duodenal switch: 2-, 5-, and 10-year data. Surg Obes Relat Dis 2016;12:1697-705. [Crossref] [PubMed]
40. Lange J, Königsrainer A. Malnutrition as a Complication of Bariatric Surgery - A Clear and Present Danger? Visc Med 2019;35:305-11. [Crossref] [PubMed]
41. Prachand VN, Davee RT, Alverdy JC. Duodenal switch provides superior weight loss in the super-obese (BMI > or =50 kg/m2) compared with gastric bypass. Ann Surg 2006;244:611-9. [PubMed]
42. Lind R, Hage K, Ghanem M, et al. Long-Term Outcomes of Sleeve Gastrectomy: Weight Recurrence and Surgical Non-responders. Obes Surg 2023;33:3028-34. [Crossref] [PubMed]
43. Möller F, Hedberg J, Skogar M, et al. Long-term Follow-up 15 Years After Duodenal Switch or Gastric Bypass for Super Obesity: a Randomized Controlled Trial. Obes Surg 2023;33:2981-90. [Crossref] [PubMed]
44. Spinos D, Skarentzos K, Esagian SM, et al. The Effectiveness of Single-Anastomosis Duodenoileal Bypass with Sleeve Gastrectomy/One Anastomosis Duodenal Switch (SADI-S/OADS): an Updated Systematic Review. Obes Surg 2021;31:1790-800. [Crossref] [PubMed]
45. Maroun J, Li M, Oyefule O, et al. Ten year comparative analysis of sleeve gastrectomy, Roux-en-Y gastric bypass, and biliopancreatic diversion with duodenal switch in patients with BMI ≥50 kg/m(2). Surg Endosc 2022;36:4946-55. [Crossref] [PubMed]
46. Marceau P, Biron S, Marceau S, et al. Long-Term Metabolic Outcomes 5 to 20 Years After Biliopancreatic Diversion. Obes Surg 2015;25:1584-93. [Crossref] [PubMed]
47. Mingrone G, Panunzi S, De Gaetano A, et al. Bariatric surgery versus conventional medical therapy for type 2 diabetes. N Engl J Med 2012;366:1577-85. [Crossref] [PubMed]
48. Hage K, Ikemiya K, Ghusn W, et al. Type 2 diabetes remission after Roux-en-Y gastric bypass: a multicentered experience with long-term follow-up. Surg Obes Relat Dis 2023;19:1339-45. [Crossref] [PubMed]
49. Pata G, Crea N, Di Betta E, et al. Biliopancreatic diversion with transient gastroplasty and duodenal switch: long-term results of a multicentric study. Surgery 2013;153:413-22. [Crossref] [PubMed]
50. Badaoui JN, Kellogg TA, Abu Dayyeh BK, et al. The Outcomes of Laparoscopic Biliopancreatic Diversion with Duodenal Switch on Gastro-esophageal Reflux Disease: the Mayo Clinic Experience. Obes Surg 2021;31:4363-70. [Crossref] [PubMed]
51. Shoar S, Poliakin L, Rubenstein R, et al. Single Anastomosis Duodeno-Ileal Switch (SADIS): A Systematic Review of Efficacy and Safety. Obes Surg 2018;28:104-13. [Crossref] [PubMed]
52. Merz AE, Blackstone RB, Gagner M, et al. Duodenal switch in revisional bariatric surgery: conclusions from an expert consensus panel. Surg Obes Relat Dis 2019;15:894-9. [Crossref] [PubMed]
53. Hage K, Barajas-Gamboa JS, Romero-Velez G, et al. Revisional Procedures after Sleeve Gastrectomy for Weight Recurrence or Inadequate Weight Loss: An Analysis of the MBSAQIP Database. J Clin Med 2023;12:5975. [Crossref] [PubMed]
54. Lind R, Ghanem OM, Ghanem M, et al. Duodenal Switch Conversion in Non-responders or Weight Recurrence Patients. Obes Surg 2022;32:3984-91. [Crossref] [PubMed]
55. Gagner M, Gumbs AA. Gastric banding: conversion to sleeve, bypass, or DS. Surg Endosc 2007;21:1931-5. [Crossref] [PubMed]