Biliopancreatic Limb Length Research Articles

BS SO11 - Impact of various biliopancreatic limb lengths on EBWL, Nutritional deficiencies and resolution of ORMs -MGB/OAGB

Abstract Background OAGB was first described by Robert Rutledge. There have been a few modifications of MGS since its first introduction. There have been modifications in the limb length, pouch side, type, and location of anastomosis. Concerns have been raised about nutritional deficiencies by various authors about the longer limb length. Few other authors have published promising results from their studies regarding good outcomes on longer limb length. Method We follow BMI based guidelines at our center to decide on OAGB limb length.BMI < 50- BP limb length – 150 cmBMI >50 BP limb length- 200 cmBMI > 60 BP limb length- 250 cm. We analysed our results from BP limb lengths >/=200 cm in terms of EBWL, ORM resolutions, Nutritional deficiencies and compared it to similar outcomes in BP limb lengths of 150 cm Results Our data is currently under review. Initial assessment suggests promising results of longer limb lengths with no major complications highlighted. All the longer limb length patients are under 3 monthly follow up with 2 years follow up data now being analysed. Literature review suggests inadequate weight loss with shorter limb lengths. The longer limb lengths are associated with nutritional deficiencies. We are excited to take this opportunity to discuss our results Conclusion Limb length should be tailored as per patient factors and available support. One standard limb length doesn't apply to all the patients.

A Longer Biliopancreatic Limb and Shorter Common Channel Enhance Weight Loss But May Have Harmful Effects in Mouse Models of Roux-en-Y Gastric Bypass.

RYGB consists of the Roux limb (RL), the biliopancreatic limb (BPL), and the common channel (CC). There is no consensus on the optimal limb lengths. Using a mouse model of RYGB, 30 diet-induced obese mice were divided into two groups with varying BPL and CC lengths: a standard BPL with a long CC (RYGB S) and a long BPL with a short CC (RYGB L). Additionally, 9 age-matched, lean control mice (LC) were also included in this study. RYGB S had limb lengths of RL = 17%, BPL = 24%, and CC = 59%. RYGB L had limb lengths of RL = 17%, BPL = 32%, and CC = 51%. RYGB S and RYGB L had 67% and 40% survival, respectively. Mortality in RYGB L included more instances where the cause of death was not apparent. RYGB L demonstrated greater weight loss, lower energy expenditure, and lower heart mass as compared to RYGB S. Both RYGB groups had lower epidydimal fat mass, spleen mass, and bone mineral density compared to LC. RYGB L had a lower heart mass than RYGB S and LC. While the relative abundance of Eubacterium was lower in RYGB L than in RYGB S, no other gut microbiota differences were observed. A longer BPL with a shorter CC induces greater weight loss but may lead to adverse effects, including lower heart mass, reduced bone density, and deaths with unclear causes.

A Meta-Analysis Comparing RYGB with Long Biliopancreatic Limb (BPL) Versus Long Alimentary Limb (AL) in Groups with Equal or Nearly Equal Combined Bypass Lengths (Combined BPL and AL Lengths): Does Switching Seats Enhance Weight Loss?

It is well-established that extending either the biliopancreatic limb (BPL), the alimentary limb (AL), or both, results in increased combined bypass (CB) length, which in turn leads to enhanced weight loss and potential nutritional deficiencies due to heightened malabsorptive effects. However, a key question remains: Assuming no change in CB length, does altering BPL length affect outcomes? To address this question, we examined studies comparing long BPL and long AL (short BPL) while maintaining equal or nearly equal CB lengths. We conducted this systematic literature review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a meta-analysis on weight loss outcomes, adverse events and safety-related outcomes, gastrointestinal complaints, and nutritional outcomes at the 2-year mark.

Metabolic and bariatric surgery in vegetarians and vegans.

Vegetarianism is constantly increasing worldwide. However, the role of metabolic and bariatric surgery (MBS) in vegetarians/vegans is unclear as there is very limited data on this topic. The aim of this study was to evaluate MBS outcomes in vegetarians or vegans. Retrospective analysis of a prospectively maintained database of a single-bariatric surgeon was carried out. All patients with a vegetarian or vegan lifestyle undergoing MBS were included. Eleven patients were included; none were lost to follow-up. Ten patients were women, the mean age and Body Mass Index (BMI) were 40.8±14 years and 43.5±4.9 kg/m2, respectively. Five patients (45%) were lacto-ovo-vegetarians, one (9%) was ovo-vegetarian, two (18%) were lacto-ovo-pesco-vegetarians, and three (27%) were vegans. Eight patients consumed vitamin supplements preoperatively, the mean albumin level was 4.1±0.2, 3/11 patients had vitamin D deficiency, 2/11 patients had vitamin-B12 deficiency, and 2/11 patients had iron deficiency. Eight patients (73%) underwent one anastomosis gastric bypass (OAGB), 2/11 patients (18%) underwent single anastomosis duodeno-ileal bypass with sleeve gastrectomy, and one patient (9%) underwent sleeve gastrectomy, the mean biliopancreatic limb length in OAGB was 225 cm. The median follow-up time was 17 months, the mean BMI and percentage of total weight loss during follow-up were 28.2±5 kg/m2 and 35.3±10.7%, respectively. The mean albumin level was 3.82±0.27, 3/11 patients had vitamin D deficiency, and 3/11 patients had iron deficiency. This study reports preliminary data on MBS outcomes in vegetarian/vegan patients. It was shown to be safe, effective, and an acceptable rate of nutritional deficiencies during follow-up. Further large cohort studies are required to clarify this data.

Effect of tailoring biliopancreatic limb length based on total small bowel length versus standard limb length in one anastomosis gastric bypass: 1-year outcomes of the TAILOR randomized clinical superiority trial.

Tailoring the biliopancreatic limb length in one anastomosis gastric bypass is proposed as beneficial in retrospective studies, yet randomized trials are lacking. The aim of this double-blind, single-centre RCT was to ascertain whether tailoring biliopancreatic limb length based on total small bowel length (TSBL) results in superior outcomes after one anastomosis gastric bypass compared with a fixed 150 cm biliopancreatic limb length. Eligible patients, meeting International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) criteria for metabolic bariatric surgery, scheduled for primary one anastomosis gastric bypass surgery, and willing to be randomized, underwent TSBL measurement during surgery. When TSBL measurement was feasible, patients were randomly assigned to a standard 150 cm biliopancreatic limb length or a tailored biliopancreatic limb based on TSBL: TSBL less than 500 cm, biliopancreatic limb 150 cm; TSBL 500-700 cm, biliopancreatic limb 180 cm; and TSBL greater than 700 cm, biliopancreatic limb 210 cm. The primary outcome was percentage total weight loss at 5 years. Between September 2020 and August 2022, 212 patients were randomized into the standard biliopancreatic limb group (105 patients) or the tailored biliopancreatic limb group (107 patients). The mean(s.d.) TSBL was 657(128) cm (range 295-1020 cm). In the tailored group, 150, 180, and 210 cm biliopancreatic limb lengths were applied to 8.4%, 53.3%, and 38.3% of patients respectively. The mean(s.d.) 1-year percentage total weight loss was 32.8(6.9)% in the standard group and 33.1(6.2)% in the tailored group (P = 0.787). Nutritional deficiencies and short-term complications showed no significant differences. Tailoring biliopancreatic limb length based on TSBL is safe and feasible. One year after surgery, it is not superior to a standard biliopancreatic limb length of 150 cm in terms of percentage total weight loss. Dutch Trial Register, NL7945.

The length of the biliopancreatic limb in one anastomosis gastric bypass.

The one-anastomosis gastric bypass (OAGB), first published by Dr Rutledge in 1997 is now a well-established procedure in the bariatric-metabolic armamentarium. This procedure based on a (single) loop gastro-jejunal anastomosis (the biliopancreatic limb or BPL) with a long narrow gastric pouch combines restriction with hypo-absorption. The biliopancreatic limb and in particular its length is held responsible for the degree of the hypo-absorptive effect but the most appropriate or "optimal" length of the BPL remains debatable. The following text is based on a comprehensive and meticulous selection of the most recent literature in Cochrane, Pubmed and Google Scholar using the search terms "biliopancreatic limb", "biliopancreatic limb in one anastomosis gastric bypass" in an attempt to define not only the most common used biliopancreatic limb length but also to find out If there is an "ideal" limb length not only to optimize the outcomes of the OAGB in terms of weight loss and resolution of obesity-related diseases but also to reduce the potential side-effects in particular nutritional deficiencies. Until today there is no consensus about the "standard" or "ideal" length of the biliopancreatic limb in OAGB, a fixed length of 200 cm is still the most common used procedure although many reports and studies are in favour of shorter limb lengths adjusted to the BMI or the total small bowel length. The "ideal" or "optimal" biliopancreatic limb length in OAGB still needs to be defined. There are different options and all of them have their credits, the question remains if a consensus can be reached regarding the best strategy to obtain the best outcome.

The Impact of Longer Biliopancreatic Limb Length on Weight Loss and Comorbidity Improvement at 5 Years After Primary Roux-en-Y Gastric Bypass Surgery: A Population-Based Matched Cohort Study

IntroductionDifferent limb lengths are used in Roux-en-Y gastric bypass (RYGB) surgery, as there is no consensus which limb length strategy has the best outcomes. The biliopancreatic limb (BPL) is thought to play an important role in achieving weight loss and associated comorbidity resolution. The objective of this study was to assess the impact of a longer BPL on weight loss and comorbidity improvement at 5 years after primary RYGB.MethodsAll patients aged ≥ 18 years undergoing primary RYGB between 2014–2017 with registered follow-up 5 years after surgery were included. Long BPL was defined as BPL ≥ 100 cm and short BPL as BPL < 100 cm. The primary outcome was achieving at least 25% total weight loss (TWL) at 5 years. Secondary outcomes included absolute %TWL and improvement of comorbidities. A propensity score matched logistic and linear regression was used to estimate the difference in outcomes between patients with long and short BPL.ResultsAt 5 years, long BPL had higher odds to achieve ≥ 25% TWL (odds ratio (OR) 1.19, 95% confidence interval (CI) [1.01 – 1.41]) and was associated with 1.26% higher absolute TWL (β = 1.26, 95% CI [0.53 – 1.99]). Furthermore, long BPL was more likely to result in improved diabetes mellitus (OR = 2.17, 95% CI [1.31 – 3.60]) and hypertension (OR = 1.45, 95% CI [1.06 – 1.99]).ConclusionPatients undergoing RYGB with longer BPL achieved higher weight loss and were more likely to achieve improvement of comorbidities at 5 years.Graphical

620 Outcomes of One Anastomosis Gastric Bypass Conversion to Roux-en-Y Gastric Bypass for Morbid Obesity: A Systematic Review and Meta-Analysis

Abstract Introduction One anastomosis or ‘mini’ gastric bypass (OAGB) is a highly effective procedure to treat morbid obesity. However, conversion to Roux-en-Y gastric bypass (RYGB) for OAGB-related complications such as bile reflux is increasing. We therefore conducted the first systematic review to determine the weight outcomes, safety and efficacy associated with OAGB-RYGB conversion surgery. Method A systematic search was conducted by three independent reviewers using Medline, Embase and the Cochrane library following PRISMA guidelines. Data extracted included patient demographics, weight, and reflux outcomes. Risk of bias was assessed using the Newcastle-Ottawa scale. The mean BMI difference was analysed using a random effects model. This study was registered on PROSPERO (Registration ID: CRD42022379759). Results 6 studies were selected which included data from 134 patients undergoing OAGB-RYGB conversion surgery. Follow-up ranged from 6-60 months. Patients' baseline BMI at conversion was 30.2 (S.D. 2.85). Common indications for conversion surgery were reflux (47.8%), malnutrition (31.3%) and inadequate weight loss (8.2%). Biliopancreatic limb length ranged from 50-200cm. Weighted mean of study outcomes demonstrated biliary reflux symptoms resolved in 90.9% cases (95 % CI 78.8-n100%). Studies reporting BMI at &amp;gt;24 months reported overall stable medium-term weight (mean BMI difference -0.71 (-4.03-2.61)) with moderate study heterogeneity (I2 = 82%). The rate of major post-op complications was 14.7% (6.25%-23.1%). Conclusions OAGB to RYGB conversion surgery is associated with a high resolution of reflux symptoms. However, it is associated with weight regain, albeit this may be acceptable to patients to treat biliary reflux as the weight gain is small and stable over the long-term.

An alternative combined revision of Roux-en-Y gastric bypass: Cover all aspects (of failure)!

The revisional surgical techniques for managing weight regain after laparoscopic Roux-en-Y gastric bypass have lacked a clear gold standard. Various methods such as pouch minimising, gastroenterostomy narrowing and distalization have been described, but none have consistently achieved optimal success. This study introduces a combined revision technique that enables the reassessment of both alimentary limb and biliopancreatic limb lengths based on the individual patient's total bowel length. This approach aims to promote effective weight loss while minimising the pouch and gastroenterostomy.

Metabolic outcomes in obese mice undergoing one-anastomosis gastric bypass (OAGB) with a long or a short biliopancreatic limb.

One-anastomosis gastric bypass (OAGB) has gained importance as a simple, safe, and effective operation to treat morbid obesity. We previously found that Roux-en-Y gastric bypass surgery with a long compared with a short biliopancreatic limb (BPL) leads to improved weight loss and glucose tolerance in obese mice. However, it is not known whether a long BPL in OAGB surgery also results in beneficial metabolic outcomes. Five-week-old male C57BL/6J mice fed a high-fat diet (HFD) for 8 weeks underwent OAGB surgery with defined BPL lengths (5.5 cm distally of the duodenojejunal junction for short and 9.5 cm for long BPL), or sham surgery combined with caloric restriction. Weight loss, glucose tolerance, obesity-related comorbidities, endocrine effects, gut microbiota, and bile acids were assessed. Total weight loss was independent of the length of the BPL after OAGB surgery. However, a long BPL was associated with lower glucose-stimulated insulin on day 14, and an improved glucose tolerance on day 35 after surgery. Moreover, a long BPL resulted in reduced total cholesterol, while there were no differences in the resolution of metabolic dysfunction-associated steatotic liver disease (MASLD) and adipose tissue inflammation. Tendencies of an attenuated hypothalamic-pituitary-adrenal (HPA) axis and aldosterone were present in the long BPL group. With both the short and long BPL, we found an increase in primary conjugated bile acids (pronounced in long BPL) along with a loss in bacterial Desulfovibrionaceae and Erysipelotrichaceae and simultaneous increase in Akkermansiaceae, Sutterellaceae, and Enterobacteriaceae. In summary, OAGB surgery with a long compared with a short BPL led to similar weight loss, but improved glucose metabolism, lipid, and endocrine outcomes in obese mice, potentially mediated through changes in gut microbiota and related bile acids. Tailoring the BPL length in humans might help to optimize metabolic outcomes after bariatric surgery.NEW & NOTEWORTHY Weight loss following OAGB surgery in obese mice was not influenced by BPL length, but a longer BPL was associated with improved metabolic outcomes, including glucose and lipid homeostasis. These changes could be mediated by bile acids upon altered gut microbiota. Further validation of these findings is required through a randomized human study.

Enteroendocrine Reprogramming by Altered Epithelial-Mesenchymal Crosstalk in Metabolic Surgery.

Metabolic surgery is an effective treatment option for type 2 diabetes. However, the therapeutic scope has been limited by unexpected inconsistent outcomes. This study aims to overcome these obstacles by determining fundamental mechanisms from a novel perspective by analyzing and comparing the surgical anatomy, clinical characteristics, and outcomes of metabolic surgery, including duodenal-jejunal bypass, Roux-en-Y gastric bypass, biliopancreatic diversion, one anastomosis gastric bypass, and their modified procedures, predominantly focusing on nonobese patients to mitigate confounding effects from overweighted type 2 diabetes. Regional epithelial cell growth and unique villus formation along the anterior-posterior axis of the small intestine depend on crosstalk between the epithelium and the underlying mesenchyme. Due to altered crosstalk between the epithelium and the opposite mesenchyme at the anastomotic site, the enteroendocrine lineage of the distal intestine is replaced by the proximal epithelium after the bypass procedure. Subsequent intestinal compensatory proliferation accelerates the expansion of the replaced epithelium, including enteroendocrine cells. The primary reasons for unsatisfactory results are incomplete duodenal exclusion and insufficient biliopancreatic limb length. We anticipate that this novel mechanism will have a significant impact on metabolic surgery outcomes and provide valuable insight into optimizing its effectiveness in type 2 diabetes.

IBC-Oxford University2023_BJSPoster_3Mini-Gastric Bypass, One Anastomosis Gastric Bypass, Tailored Biliopancreatic, Bypass vs. Weight Loss

Abstract Introduction Studies of different Bariatric procedures have resulted in conflicting findings on the effects of the surgery on daily Dietary Food Choices (DFCs.) Some suggest a pure volume effect, others report changes in type and preferences and still others suggest the effects change over time. The Biliopancreatic Limb (BPL) length in the One Anastomosis Gastric Bypass (OAGB), Mini-Gastric Bypass-Original Technique (MGB-OT) version, includes a "tailored" BPL length. The purpose of this study was to investigate the relationship between BPL length and DFCs in patients undergoing MGB-OT. The primary hypothesis was that the changes in dietary habits and food choices would be related to the BPL length in the MGB-OT. Methods Data from a long term online patient survey including MGB-OT patients were collected including basic demographics, MGB-OT BPL length, patient reported DFCs and weight loss classes. Linear regression modelling was used to assess the relative association between BPL length with various mean patient reported DFCs and a composite model of Food Choices. Results 286 patients had responses for evaluation. Patients with BPL lengths of 3 to 9 ft (92-274cm) were selected. As reported in prior publications, patient reported mean weight loss classes varied linearly related to BPL length. The mean "Bad" Food Choices (BFC) declined from 5.7/day to 2.0/day. The mean composite "Bad" food choices declined from a mean of 2,070 DFCs per year to an estimated 745. There was a strong linear relation between BPL length and the decline in mean "Bad" daily food choices. (y=-0.3x-3, R2 = 0.7, p&amp;lt;0.05.) Conclusions The present study of mean patient reported DFC outcomes following a "Tailored" BPL length in the MGB-OT version of the OAGB declined substantially. The patient dietary food choices for fried foods, sugar sweetened beverages, processed meats and junk foods all declined. These changes were linearly related to the Bilio-pancreatic limb length. In cases of the MGB-OT a longer Bilio-pancreatic Limb Length was associated with greater weight loss and a greater improvement in daily Dietary Food Choices. If confirmed by other studies the possibility of tailoring the power of a bariatric operation based upon BPL length seems like an important advancement in bariatric surgery.

IBC-Oxford University2023_BJSPoster_4Biliopancreatic Limb Length and Patient Satisfaction One Anastomosis Gastric Bypass (Mini-Gastric Bypass-Original Technique)

Abstract Introduction Daily Food Choices (DFCs) in obesity and Bariatric Surgery (BS) are critical components of patient’s health. The Biliopancreatic Limb (BPL) length in the Mini-Gastric Bypass-Original Technique (MGB-OT) version of the One Anastomosis Gastric Bypass (OAGB) includes a “Tailored" BPLL designed to change the outcome of the operation related to patient needs. The purpose of this study was to investigate the relationship between the impact of the MGB-OT and the "Tailored" BPL length, on weight loss and patient-reported DFCs. The primary hypothesis was that the MGB-OT would be associated with major changes in both DFCs and weight loss and that the “Tailored" BPL length would be associated with both DFCs and weight loss. Methods Data from an online patient survey of MGB-OT patients were collected including basic demographics, BPL length, pre and post-operative DFCs and weight loss. Linear regression modelling was used to quantitate the relative association between MGB-OT and the "Tailored" BPL length with DFCs and weight loss. Results 377 patients had complete responses for evaluation; 72% of patients were female, mean age 48+/-15 range 24-80 years; mean BPL length was 2.0+/-0.3m range 0.9-2.7m, mean preop weight was 131.0+/-24.2 range 86.3-222.5kg, mean post weight was 82.6+/-20.0 range 47.2-193.0, mean weight loss 48.4+/-19.2 range 6.4-119.4 and Percent Total Weight Loss (%TWL) was 36.9%+/-8.0% range 6.4%-53.7%. 90.8% of patients reported %TWL greater than 20%. As reported elsewhere, various measures of weight loss varied linearly related to BPL length. The mean DFCs of Meat, Sugar-Sweetened Beverages and Fatty Foods (Meat, SSBs and FFs respectively) were all higher before MGB-OT and declined post-op. The mean “Bad” Food Choices (Bad DFCs = DFCs Meat+SSBs+FFs) declined from mean of 8.6+/-0.9 to 5.0+/0.7 a Delta “Bad” DFCs of 3.6+/-0.9. Daily DFCs of Fresh Fruit and Vegetables (FFVs) increased, Delta FFVs 1.2+/-0.1. The Delta All DFCs, (Delta Bad+FFVs) was 4.8+/-1.0/day with an estimated Delta of 1,757 “Yearly” Food Choices (YFCs.) The estimated Yearly “Bad” food choices declined from 2,070 YFCs to an estimated 745. Finally, there was a strong linear relation between BPL length and the decline in mean “Bad” daily food choices. Conclusions The present study demonstrates that patients report major weight loss following a “Tailored" BPL length in the MGB-OT. Patients also reported declines in “Bad” DFCs (meat, FFs &amp; SSBs) and improvements in FFVs. Yearly projections of these changes suggest both an improvement in quality and a decrease in caloric intake of hundreds of thousands of calories per year. Both these were linearly related to Biliopancreatic limb length. A longer Biliopancreatic Limb Length was associated with greater weight loss and a greater improvement in patient-reported Daily Food Choices.

IBC-Oxford University2023_BJSOral_3Tailored Bilio-Pancreatic Limb Length and Haemoglobin A1c Levels 10 years following Mini-Gastric Bypass Original Technique of One Anastomosis Gastric Bypass

Abstract Introduction The need for or the ideal length of the Biliopancreatic Bypass limb (BPL) length is a controversial topic. The Mini Gastric Bypass original technique (MGB-OT) version of the One Anastomosis Gastric Bypass (OAGB) includes a “Tailored” BPL length. This study aimed to investigate the 1 to 10-year outcomes of the “Tailored’ BPL length in patients undergoing MGB-OT in diabetic patients with Class III obesity. Methods The study is a retrospective chart review of 114 patients who underwent the Mini Gastric Bypass original technique (MGB-OT) with a tailored Biliopancreatic Limb length as described by Rutledge et al. These cases were performed between June 2008 and December 2009. The study investigated the relationship between the length of the BPLL and glycaemic control, primarily as measured by the change in (Delta) HbA1c levels, in morbidly obese diabetic patients undergoing the MGB-OT. The mean BPL length in the study was 185 cms, with a range of 120-350 cms. The study analysed preoperative, post-operative, and Delta HbA1c levels as the primary outcomes. The critical outcome goal for the study was HbA1c levels of less than 7%, which is a commonly used target for glycaemic control in diabetic patients. Results Only 89 of 114 (78%) patients completed the 10-year follow-up. The mean preoperative HbA1c was 9.2+/-1.6 (range 6.8-14.7). Longer BPL length were selected for patients based on a variety of patient factors including the patient’s preoperative HbA1c levels. Patients with longer BPL length had greater weight loss (R2 0.8.) The mean HbA1c levels were 5.50+/-0.36, 5.65+/-0.35, and 5.82+/-0.41 at 1, 5, and 10 years post-op. 100% of patients evaluated at 1 and 5 years had HbA1c levels below 7%, and only 1 out of 89 patients at 10 years had HbA1c levels above 7%. The correlation between BPL length and the 10-year Delta HbA1c was high, with a correlation coefficient (r) of 0.8. The Delta HbA1c was significantly greater in the patients with BPL length &amp;gt; 150 cm (3.99 +/- 1.87 vs 2.08 +/- 0.71 in the BP150 patients difference 1.91, SEM 0.40, 95% CI 1.12 to 2.69, P &amp;lt; 0.0001) i.e., longer BPL length (&amp;gt; 150cms) had significantly greater Delta HbA1c than 150 cm BPL length. Conclusions The study suggests that individualized tailoring of the biliopancreatic limb length in the OAGB procedure can potentially lead to a combination of excellent weight loss and near-complete normalization of HbA1c levels for up to 10 years. However, this a small and incomplete study and the optimal length may vary based on individual patient factors. Further research is needed to confirm these findings and establish standardized guidelines for determining the appropriate BPL length. Overall, the study highlights the importance and potential value of continued research and individualized treatment approaches for patients with obesity and diabetes.

New Mouse Models of Roux-en Y Gastric Bypass and One Anastomosis Gastric Bypass for Type 2 Diabetes.

Current bariatric surgery models primarily utilize mice with obesity, overlooking those with type 2 diabetes (T2DM). These models have limitations in replicating clinical procedures accurately and achieving broad applicability. This study aimed to develop novel mouse models of Roux-en-Y gastric bypass (RYGB) and one anastomosis gastric bypass (OAGB) surgeries specifically designed for T2DM research, utilizing simplified surgical techniques closely resembling clinical procedures. Eight-week-old C57/Bl6 mice, except for the Blank-Control group, were induced with T2DM by combining a high-fat diet and streptozotocin injection. RYGB involved creating a 10% gastric pouch, a 4-cm biliopancreatic limb (BL), and a 4-cm Roux limb (RL). Similarly, OAGB maintained a 10% gastric pouch and a 4-cm BL. To assess the efficacy of these models, we measured the body weight and fasting blood glucose (FBG) and conducted intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test (ITT), and liver B-ultrasound, as well as a histopathological analysis of multiple organs 12weeks post-operation. The survival rates in the Blank-Control, T2DM-Sham, T2DM-RYGB, and T2DM-OAGB groups were 100% (6/6), 100% (6/6), 85.7% (6/7), and 100% (6/6), respectively. Both RYGB and OAGB surgeries similarly led to sustained weight loss, reduced the FBG levels, improved the IPGTT and ITT results, and alleviated the histopathological manifestations in multiple organs. The innovative mouse models of RYGB and OAGB surgeries effectively improve T2DM. Both surgeries demonstrate comparable efficacy in ameliorating T2DM, even when utilizing a gastric pouch of the same size and the same length of BL in OAGB.

Optimal Small Bowel Limb Lengths of Roux-en-Y Gastric Bypass.

Gastric bypass and biliopancreatic diversion (BPD) have come full circle, from a loop configuration to a Roux-en-Y and finally back to a loop configuration as one anastomosis gastric bypass and single-anastomosis duodenal switch. Most surgeons performing Roux-en-Y gastric bypass (RYGB) do not measure the common channel (CC) length and most surgeons performing BPD do not measure the biliopancreatic limb length (BPL). The small bowel length in humans is variable from as short as < 400cm to as long as > 1000cm. The combination of these two facts means that even if surgeons keep the limb lengths constant, surgeons will get variable limb length due to the variability of small bowel length in patients. Hence, outcomes of weight loss, resolution of medical problems, or developing nutritional deficiencies which are related to limb length are variable. In this article, we evaluate the published literature related to the effect of varying the Roux limb, BPL, CC, and total alimentary limb lengths on the outcomes of RYGB. We have focused on historical and current randomized controlled trials as well as systematic reviews and meta-analysis to outline the current literature and our interpretation of this literature.

BP Limb Length as a Factor for T2DM Remission

Background: There has been increased interest in identifying the associated factors to Type 2 Diabetes Mellitus (T2DM) remission after bariatric surgery. One of these factors is the BP limb length. The objective of our study was to evaluate the T2DM remission rate in patients subjected to Roux -en- Y gastric bypass (RYGB) who had different Biliopancreatic (BP) limbs length. Methods: 48 patients with obesity grade II, and T2DM diagnosis, were subjected to RYGB and completed a one year of surgical follow up. All patients were grouped according to the BP limb length: In group A (n= 24) patients with BP limbs of 100 cm or less; in group B (n= 24) patients with BP limb from 150 to 170 cm in length. Results: Both groups presented an elevated remission rate of T2DM (83% full remission in the population studied). In group A 18 patients (75%) presented a full remission, while 2 patients (8.3%) showed a partial remission and only 4 patients (16.7%) were considered without remission at the one year follow up. In group B all patients had some remission: 22 patients (91.7%) presented a full remission (91.7%) and the rest of the patients showed a partial remission (8.3%), no significant difference was found between the two groups. Conclusions: Bariatric surgery remains as the best long term treatment for obesity and its comorbidities, despite some differences in the RYGB technique, BP limb length from 50 to 170 cm did not affect post RYGB glycemic control.

BS O03 Nutritional Complications After LaparoscopicRoux-en-Y Gastric Bypass and One-AnastomosisGastric Bypass: A Comparative Systematic Review and Meta-Analysis

Abstract Background This systematic review and meta-analysis were done to assess the incidence of nutritional complications at follow-up after one-anastomosis gastric bypass (OAGB) and Roux-en-Y gastric bypass (RYGB). Methods A systematic review and meta-analysis were carried out involving studies that compared the nutritional complications of Roux-en-Y gastric bypass (RYGB) and one-anastomosis gastric bypass (OAGB); these included the incidence of malnutrition as well as deficiencies of other nutritional elements, such as total protein, albumin, calcium, and iron. A comprehensive search strategy was implemented in PubMed, Embase, and the Cochrane Library. Effect sizes included the pooled odds ratios (ORs) and 95% confidence intervals (95% CIs), as well as mean differences (MDs) and 95% CIs of the percentage total weight loss (%TWL) and excess weight loss percentage (%EWL). Results Thirteen studies were included (12,964 patients, 66.27% females, 53.82% underwent OAGB). At the longest follow-up period (≥3 years), OAGB was associated with significantly higher %TWL (MD=5.41%, 95%CI, 1.52 to 9.29) and %EWL (MD=13.81%, 95%CI, 9.60 to 18.02) compared to RYGB. However, OAGB procedures were associated with malnutrition (OR=3.00, 95%CI, 1.68 to 5.36, p&amp;lt;0.0001), hypoalbuminemia (OR=2.38, 95%CI, 1.65 to 3.43, p&amp;lt;0.0001), hypoproteinemia (OR=1.85, 95%CI, 1.09 to 3.14, p=0.022), anemia (OR=1.38, 95%CI, 1.08 to 1.77, p=0.011), and hypocalcemia (OR=1.78, 95%CI, 1.01 to 3.12, p=0.046). On subgroup analyses, the proportions of anemia and hypoalbuminemia remained significantly higher at longer follow-up periods and in studies published in Asia. Conclusions Despite the favorable weight loss profile, the unfavorable nutritional consequences of OAGB merit further investigations to explore the malabsorptive element, ethnic variation, and the role of the biliopancreatic limb length.

Biliopancreatic Limb Length as a Potential Key Factor in Superior Glycemic Outcomes After Roux-en-Y Gastric Bypass in Patients With Type 2 Diabetes: A Meta-Analysis.

Optimal length of biliopancreatic (BP) and Roux limb in Roux-en-Y gastric bypass (RYGB) for improved glycemic control are not known. To investigate how the lengths of the BP and Roux limbs in RYGB differentially affect postoperative glycemic outcomes in patients with type 2 diabetes. We conducted a systematic literature search using the PubMed, Embase, and the Cochrane Library databases. We included studies that reported glycemic outcomes after RYGB and lengths of the BP and Roux limbs. A total of 28 articles were included for data extraction. Glycemic outcomes after RYGB were assessed on the basis of two definitions: remission and improvement. We categorized the included studies into four groups according to the BP and Roux limb lengths. The type 2 diabetes remission/improvement rates were as follows: long BP-long Roux group 0.80 (95% CI 0.70-0.90)/0.81 (0.73-0.89), long BP-short Roux group 0.76 (0.66-0.87)/0.82 (0.75-0.89), short BP-long Roux group 0.57 (0.36-0.78)/0.64 (0.53-0.75), and short BP-short Roux group 0.62 (0.43-0.80)/0.53 (0.45-0.61). Meta-regression analysis also showed that a longer BP limb resulted in higher postoperative type 2 diabetes remission and improvement rates, whereas a longer Roux limb did not. There was no significant difference or heterogeneity in baseline characteristics, including diabetes-related variables, among the four groups. Not all included studies were randomized controlled trials. Longer BP limb length led to higher rates of type 2 diabetes remission and improvement by 1 year after RYGB in comparisons with the longer Roux limb length.

Roux-en-Y gastric bypass with a long versus a short biliopancreatic limb improves weight loss and glycemic control in obese mice.

Roux-en-Y gastric bypass (RYGB) results in long-term weight loss and reduced obesity related co-morbidities. However, little is known about how the lengths of the biliopancreatic limb (BPL), the alimentary limb (AL), and the common limb (CL) affect weight loss and glucose metabolism. Our aim was to establish a RYGB obese mouse model with defined proportions of the AL and BPL and a constant CL to assess the effects on weight loss,glucose metabolism, and obesity-related co-morbidities. In vivo mouse study. Six-week-old male C57BL/6J mice fed with a high-fat diet (HFD) underwent bariatric surgery with defined BPL lengths: a very long, long, and short BPL (35%, 25%, and 15% of total bowel length), or sham surgery. The length of the AL was adjusted to achieve the same CL length. Mice were analyzed for weight loss, glycemic control, and obesity-related co-morbidities. Mice undergoing RYGB surgery with a very long BPL had excessive weight loss and mortality and were therefore not further analyzed. Mice with a long BPL showed a significantly increased total weight loss when compared with mice with a short BPL. In addition, a long BPL improved glucose tolerance, particularly early after surgery. A long BPL was also associated with lower triglyceride levels. Resolution of hepatic steatosis and adipose tissue inflammation was, however, not statistically significant. Of note, bariatric surgery dramatically changed gut microbiota, regardless of limb length. In obese mice, a long BPL results in enhanced weight loss and improved glucose tolerance. These findings could potentially be translated to humans by tailoring the BPL length according to body weight, obesity-related co-morbidities, and total bowel length of an individual patient.