Laparoscopic One Anastomosis Gastric Bypass as a Revisional Procedure After Failed Vertical Banded Gastroplasty: Our Center Experience.

Introduction It has been observed that 5–8% of primary bariatric procedures result in treatment failure, necessitating the need for revisional surgery. Single anastomosis duodeno-ileal bypass (SADI) and one anastomosis gastric bypass (OAGB) have been suggested as technically less complex but equally efficient substitutes for the Roux-en-Y procedures. In this systematic review and meta-analysis, our aim is to compare the effectiveness of SADI and OAGB in addressing weight regain following sleeve gastrectomy. Methods We systematically searched PubMed, Scopus, Web of Science and Cochrane Central Register of Controlled Trials databases. Studies were considered eligible if compared SADI with OAGB as revisional surgeries following sleeve gastrectomy. Weight loss parameters included total weight loss percentage (TWL%) and excess weight loss percentage (EWL%). Results Our search strategy yielded 4 articles with a total of 309 patients. 151 patients were assigned to SADI group, on the other hand 158 patients were assigned to OAGB group. For weight loss parameters comparing both procedures at 1 year, the results were in favor of SADI with an EWL% (95% c.i. 3.90 to 17.66; P < 0.01) and a TWL% (95% c.i. 2.43 to 6.17; P < 0.01). At 2 years of follow-up EWL% did not show a statistically significant difference between both operations (95% c.i. −1.18 to 25.86; P = 0.07). In contrast, TWL% was significantly higher in SADI compared to OAGB (95% c.i. 0.96 to 9.68; P = 0.02) at 2 years of follow-up. Regarding post-operative bile reflux, OAGB group had a significantly higher incidence of biliary reflux (OR 0.15; 95% c.i. 0.04 to 0.53; P = 0.003). Patients enrolled in SADI did not develop anastomotic ulcers according to the 4 studies included in the analysis. In contrast, 7 patients in OAGB group did develop anastomotic ulcers but the difference was not statistically significant (OR 0.23; 95% c.i. 0.05 to 1.10; P = 0.07). Conclusion SADI is a feasible procedure with a favorable outcome compared to OAGB as a revisional surgery following sleeve gastrectomy regarding weight loss at 1 year with a lower incidence of post-operative biliary reflux.

The YOMEGA study (Y-study) was a randomized trial comparing one anastomosis gastric bypass (OAGB) and Roux-en-Y gastric bypass (RYGB). Here, we aim to compare the Y-study and our pioneer trial from Taiwan (T-study). Data from the Y-study and the T-study were collected and compared. The Y-study recruited 234 patients with a mean body mass index (BMI) of 43.9 and age of 43.5years. The T-study recruited 80 patients with a similar mean BMI of 44.3 and mean age of 31.4years. The studies had similar findings including (1) OAGB is easier and possibly safer procedure than RYGB. Both studies showed that OAGB had a shorter operation time than RYGB, but a lower surgical complication rate was only demonstrated in T-study. (2) Both procedures have similar weight loss but OAGB features better glycemic control than RYGB. Weight loss at 2years after surgery was similar between two procedures, but OAGB reduced HbA1c to a greater degree than RYGB at 2years in Y-study (- 2.3% vs. - 1.3%; p = 0.025). The resolution of the metabolic syndrome was 100% for both groups in the T-study. (3) OAGB carried a higher risk of malnutrition. OAGB had more malabsorptive problems with a lower hemoglobin level than RYGB at 2years after surgery. Adverse malnutrition events occurred in nine (7.8%) OAGB patients in the Y-study. Four (3.4%) patients of OAGB received revision surgery in Y-study but none in T-study. (4) Bile reflux was noted in OAGB patients but did not influence quality of life or revision rate. Y-study found that bile in the gastric pouch was present in 16% of patients in the OAGB group versus none in the RYGB, but no inter-group difference in quality of life was detected. There was a trend for RYGB patients to experience more abdominal pain than OAGB. Both studies showed that OAGB is a technically easier procedure and features better glycemic control than RYGB, but has a mal-absorptive effect. However, the bile reflux and abdominal pain controversies persisted.

One Anastomosis Gastric Bypass (OAGB) is a modification of Mason's loop bypass procedure, which has become a well-established procedure in the field of Bariatric and Metabolic surgery (BMS). However, the optimal length of Biliopancreatic Limb (BPL) in OAGB remains an ongoing debate. This review aims to analyse the current trends and evidence regarding different BPL lengths in OAGB and their impact on outcomes. A comprehensive literature search using search terms, 'One Anastomosis Gastric Bypass', 'Mini-Gastric Bypass', 'Biliopancreatic Limb', and 'Small bowel limb' was conducted. The articles were extracted and critically appraised for various outcomes including weight loss, comorbidities resolution, nutritional deficiencies, complications and quality of life. There appears to be a direct relationship between length of the BPL and the incidence of malnutrition. Longer BPL lengths (> 200cm) are associated with a higher risk of malnutrition. Shorter BPL lengths (150-200cm), particularly 150cm, have shown promising outcomes. Shorter BPL lengths offer potential advantages by reducing nutritional risks associated with OAGB. Further research with long-term follow-up is needed to investigate the efficacy of even shorter BPL lengths (< 150cm).

Whether one anastomosis gastric bypass (OAGB) or Roux-en-Y gastric bypass (RYGB) is a better revisional bariatric surgery (RBS) after sleeve gastrectomy (SG) is still under debate. The aim is to compare short-term outcomes of RYGB and OAGB as a RBS after SG, pertaining to their effects on weight loss, resolution of comorbidities, and complications. We performed a single-center analysis of 55 patients (n = 34 OAGB, n = 21 RYGB). Indications for revisional surgery included weight regain/loss failure (67%) and intractable gastroesophageal reflux disease (33%). Data were collected up to 1-year follow-up (FU) and included time of revisional surgery, operation time, weight, body mass index, excess weight loss, and total weight loss (TWL), both in percent, complications and resolution of comorbidities. Operation time was 79 ± 36 (OAGB-MGB) and 98 ± 24min (RYGB) (p = 0.03). In the first 30 postoperative days, three patients in the RYGB group, and no patient in the OAGB group, had postoperative complications. FU was 100%. Minor complication rates at 12months were 33.3% (RYGB) and 35.3% (OAGB). At 12months, mean % TWL was 10.3 ± 7.6% (RYGB) and 15.8 ± 7.8% (OAGB) (p = 0.0132). OAGB after failed SG was found to be a quicker procedure with less perioperative complications. At 1-year FU, no significant differences were seen between RYGB and OAGB regarding readmission and minor complications. Still long-term FU including the risk of malnutrition is needed to have a complete evaluation of OAGB as a RBS for the future.

This study aims to evaluate and compare long-term results of laparoscopic sleeve gastrectomy (LSG) and one anastomosis gastric bypass (OAGB) based on bariatric analysis reporting and outcome system (BAROS) score. Patients operated for morbid obesity between 2013 and 2015 were randomised to LSG and OAGB groups. Based on inclusion and exclusion criteria, 201 patients (100 LSG and 101 OAGB) were analysed for changes in total body weight (TBW), body mass index (BMI), percent excess weight loss (%EWL), percent total weight loss (%TWL), QoL (quality of life) scores, comorbidity resolution and outcome based on BAROS at 7years. Sixty-six LSG and 64 OAGB patients were followed up at 7years. Mean pre-operative TBW and BMI were 119 ± 28.2 and 44.87 ± 7.71 for LSG group and 113.25 ± 23.74 and 44.71 ± 8.75 for OAGB group respectively. At 7years after surgery, there was significant drop in mean TBW and BMI in both groups. Mean %EWL for LSG and OAGB patients was 50.78 ± 28.48 and 59.99 ± 23.32 and mean %TWL for LSG and OAGB patients was 23.22 ± 12.66 and 27.71 ± 12.27 respectively. Mean QoL scores at 7years were significantly higher than the pre-operative scores and most of the patients in both groups had remission or improvement in their comorbidities. 68.76% OAGB patients had very good or excellent outcome on BAROS score while only 36.37% LSG patients had similar outcome. LSG and OAGB are successful bariatric procedures over the long term. OAGB outperforms LSG and has significantly higher %EWL and %TWL over the long term.

Introduction Roux-en-Y gastric bypass (RYGB) is currently regarded as the predominant method for bariatric surgery. However, one anastomosis gastric bypass (OAGB) emerged after RYGB as a more straightforward and readily reversible operation. In this systematic review and meta-analysis, our aim is to compare both procedures and update the currently existing evidence. Methods We systematically searched PubMed, Scopus, and the Cochrane Central Register systematically searched for randomized controlled trials (RCTs) that compared OAGB with RYGB as primary operations in terms of weight loss, comorbidities resolution, and post-operative complications in bariatric patients. Revisional surgeries were excluded from the analysis. Results Twelve studies were included in this meta-analysis, with a total of 904 patients. 445 patients were assigned to OAGB group (0.49%). The follow-up periods ranged from 6 months to 60 months. Total weight loss percentage (TWL%) was statistically higher in OAGB group at 6 months (95% c.i.:0.80 to 2.94; P = 0.006) with no differences at 12, 24, 36 months when compared to RYGB. On the other hand, OAGB exhibited a significantly higher excess weight loss percentage (EWL%) in comparison to RYGB at 12 months (95% c.i.: 3.08 to 9.73; P = 0.0002). EWL% was comparable in both procedures at 6, 24, 60 months of follow-up, which suggests that OAGB yields similar weight loss outcomes when compared to RYGB. There were no statistically significant differences in terms of resolution of diabetes mellitus, hypertension, dyslipidemia, obstructive sleep apnea and musculoskeletal pain. De Novo gastro-esophageal reflux disease (GERD) (RR 2.58; 95% c.i. 1.55 to 4.3; P = 0.0003) and marginal ulcers (RR 2.7; c.i. 95% 1.07 to 6.84; P = 0.04) were significantly higher in patients who underwent OAGB in comparison to RYGB. In contrast, diarrhea and dumping syndrome had a similar incidence in both procedures. Conclusion In conclusion, OAGB is not inferior to RYGB in terms of weight loss parameters and comorbidities resolution. However, OAGB can lead to a higher risk of development of marginal ulcers and de Novo GERD.

Laparoscopic sleeve gastrectomy (LSG) is one of the most popular bariatric procedure. One anastomosis gastric bypass (OAGB) is rapidly emerging as a safe and effective metabolic procedure. This study aims at comparing the 1-year follow-up results of OAGB and LSG in terms of excess weight loss, complications, resolution of comorbidities, and quality of life. A prospective randomized study of results between 100 LSG and 101 OAGB patients was done from 2012 to 2015. The results were compared regarding operative outcomes, percentage of excess weight loss, complications, resolution of comorbidities, and quality of life (BAROS score). The mean BMI for the OAGB and LSG group was 44.31 and 43.75kg/m2, respectively. Percentage of excess weight loss (%EWL) for OAGB vs LSG was 66.87±10.87 vs 63.97±13.24 at 1year (p>0.05), respectively. Diabetes remission was 83.63% in OAGB patients and 76.58% in LSG patients. Remission of hypertension is 64.15% in OAGB patients and 66.07% in LSG patients. Bariatric Analysis Reporting and Outcome System (BAROS) was 3.71 in LSG and 3.96 in OAGB. In our study, there was no significant difference between LSG and OAGB in outcome at 1year follow-up in % excess weight loss, remission of HTN, and quality of life. OAGB has marginally better outcome in T2 DM remission. However, a longer follow-up is required to establish a correct comparative result.

One anastomosis gastric bypass (OAGB) is gaining popularity among bariatric procedures. However, data on the number and outcomes of revisional surgeries is scarce. This study included patients undergoing OAGB revision in a high-volume centre between January 2020 and October 2024. The study evaluates the indication for revision, the type of procedure performed, and the success of revisional surgery, assessed by symptom resolution or percent excess weight loss (%EWL) > 40% at 2 years. OAGB was performed on 3280 patients, of which 52 (1.6%) necessitated surgical revision for late complications as well as 18 patients who had their primary OAGB elsewhere. A total of 68 patients (47 females, 21 males) underwent OAGB revision. The mean time to revision after primary OAGB was 28 months. Indications for revision in the 68 patients were recurrent weight gain (51.5%, 0.73% of the total), severe bile reflux (29.4%, 0.52% of the total), marginal ulcers (7.4%, 0.12% of the total), excessive malabsorption (5.9%, 0.06% of the total), and stenosis (5.9%, 0.12% of the total). Revisional procedures in the 68 patients included biliary-pancreatic limb lengthening (47%), conversion to RYGB (29.4%), redo gastro-jejunal anastomosis (13.3%), biliary-pancreatic limb shortening (5.9%), and pouch resizing (4.4%). There were no major postoperative complications and 5.8% minor complications, all managed conservatively. At 20 months, 98.5% of revisional surgeries were successful, with complete symptom resolution for reflux, anastomotic ulcers and stenosis. The mean of %EWL in the recurrent weight gain group was 33.7%, 57.4% and 84% at 3 months, 1 year and 2 years. OAGB appears to be a safe procedure with a low revision rate. When necessary, surgical revision procedures can be tailored and have a high success rates and low morbidity. A management algorithm has been developed and proposed.

One anastomosis gastric bypass (OAGB) is a relatively novel technique with excellent outcomes, comparable to most accepted procedures. Our aim was to compare OAGB and Roux-en-Y gastric bypass (RYGB) in terms of percent of excess weight lost (%EWL) and resolution of comorbidities. Thirty-three patients were randomly assigned (1:2) to two groups (OAGB = 9 and RYGB = 24). Patients were analyzed prospectively. The 5-year follow-up was 85% (28 patients). Both groups were comparable preoperatively in age, weight, body mass index (BMI), and excess weight. One intraoperative complication in OAGB group and no major postoperative complications for both groups were recorded. Progressive decrease in weight, BMI, and %EWL was observed at 1, 6, 12 months, and 5 years, with no differences between groups. Regarding comorbidities, we registered complete remission in type 2 diabetes mellitus (T2DM), insulin resistance, and dyslipidemia with OAGB. RYGB group reported complete remission in T2DM, insulin resistance, dyslipidemia, and gastroesophageal reflux disease (GERD). Mean operative time were 113.3 min ± 41.2 and 143.7 min ± 21.85 for OAGB and RYGB respectively. Mean number of reloads used was 5 for OAGB and 7 for RYGB, which demands further investigations. Postoperative pain was significantly higher in RYGB group. Hospital stay was 3 days for both groups. At 5-year follow-up, patients of both techniques achieved similar outcomes in terms of %EWL and resolution of comorbidities, without early or mid-term major complications and no mortality. OAGB demonstrated less use of surgical stapling and unexplainably less postoperative pain compared to RYGB.

Bile reflux (BR) is an issue after one anastomosis gastric bypass (OAGB). Cholecystectomy can increase BR in patients without a history of metabolic and bariatric surgery. We aimed to evaluate the effect of cholecystectomy on BR after OAGB. This prospective observational study was conducted between March 2017 and December 2022 including 34 matched adult individuals with a body mass index ≥ 40kg/m2 or ≥ 35 in the presence of comorbidities and gallstone disease in preop evaluations who underwent primary OAGB including 17 patients who had undergone cholecystectomy simultaneously or after OAGB (OAGB + LC) and 17 patients without cholecystectomy (OAGB). All patients underwent evaluations for gastroesophageal reflux disease (GERD) and bile reflux (BR) using various methods including esophagogastroduodenoscopy (EGD), the GERD-Q questionnaire, and a hepatobiliary iminodiacetic acid (HIDA) scan. Thirty-four patients were included in this study. BR into the esophagus was not detected in both groups. BR to the gastric pouch was observed in 4 patients (23.5%) of the OAGB group and 6 patients (35.3%) of the OAGB + LC group (P = 0.452). BR to gastric remnant was observed in 6 patients (one and five patients in OAGB and OAGB + LC groups respectively) (P = 0.072). There was no statistically significant difference between the two groups, although it was clinically significant. Cholecystectomy after OAGB is not associated with a change in the rate of BR in the gastric pouch but increases the incidence of BR into gastric remnant that may be harmful in the long term.

One-Anastomosis Gastric Bypass (OAGB) has become an established bariatric procedure globally, known for its technical simplicity and favorable outcomes. Despite its increasing adoption, OAGB remains under scrutiny for long-term safety and efficacy. This study aims to evaluate the clinical outcomes, safety, and resolution of obesity-related comorbidities following OAGB with a biliopancreatic limb (BPL) of 150cm length, performed in a single center, over a three-year period. This retrospective study included all patients who underwent laparoscopic OAGB between October 2020 and October 2023. The procedure was standardized with a BPL of 150cm length. Data were collected and analyzed retrospectively to assess weight loss outcomes, resolution of comorbidities, and perioperative and late complications. Overall, 102 patients underwent OAGB during the study period, with 76% being female and a mean age of 35.7 ± 8.34years. The mean preoperative weight and body mass index (BMI) were 125 ± 16.2kg and 46 ± 7.6kg/m2, respectively. The total weight loss (TWL) was 32,78 ± 5.57% at one year, 37,45 ± 4.36% at two years, and 37,85 ± 4.74% at three years. Significant improvements were noted in obesity-related comorbidities: 92% of patients with type 2 diabetes (T2D) experienced remission at one year, sustained at three years in 82%. Early complications were observed in 3.92% of cases, while late complications occurred in 7.84%, with no postoperative deaths or internal hernia reoperations during the three-year follow-up. Iron and ferritin deficiencies were identified in 4.9%, hypoalbuminemia (< 35g/l) in 1.96%, and anemia (< 12g/dl) in 4.9% of patients, with no patients requiring revision for malnutrition. OAGB demonstrates high efficacy in achieving substantial weight loss and resolving comorbidities, with an acceptable safety profile when using a BPL of 150cm. The findings support the continued adoption of OAGB as a primary bariatric surgery when performed with standardized techniques and multidisciplinary follow-up.

Previous studies showed a high conversion rate and failure of restrictive procedures, including sleeve gastrectomy (SG), adjustable gastric banding (AGB), gastric plication (GP), and vertical banded gastroplasty (VBG) in a long-term follow-up. The current study aims to evaluate the efficacy and safety of a revisional one anastomosis gastric bypass (OAGB) for weight loss and treatment of obesity-related problems after primary metabolic and bariatric restrictive procedures. A retrospective study on prospectively collected data was conducted on a sample of 151 patients who experienced insufficient weight loss or weight regain after primary restrictive surgeries and underwent OAGB as a revisional procedure. A total of 151 patients with a history of previous restrictive metabolic and bariatric surgery who underwent a revisional OAGB were included in this study. The restrictive procedures consisted of SG (n = 79), AGB (n = 45), GP (n = 15), and VBG (n = 12). Total weight loss percent (%TWL) after the revisional OAGB was 27.03 ± 9.12, 27.74 ± 10.05, 24.62 ± 9.87, and 24.34 ± 8.05 after 12, 24, 60, and 84 months, respectively. After 24 months of follow-up, TWL was significantly higher in the GP group compared to the AGB group. However, weight loss outcomes were not significantly different after 60 months of follow-up. The revisional OAGB was associated with a significant resolution of obesity-related problems, including type 2 diabetes (55.55%), hypertension (50%), dyslipidemia (77%), and obstructive sleep apnea (100%) after 2 years of follow-up. There was no serious complication after the revisional OAGB in the short- and long-term follow-up. OAGB is an efficient and safe option as a conversion surgery after restrictive procedures.

In 2001, Rutledge reported the first case of mini gastric bypass (MGB). Carbajo improved the technique of MGB and named it one anastomosis gastric bypass (OAGB). Over the past 20 years, a large number of clinical and basic studies on OAGB/MGB have been reported, and the answers to some key questions about OAGB/MGB have gradually become clear. From a technical point of view, MGB and OAGB can be regarded as two subvariants of one surgery. The advantages of OAGB/MGB include: (1) simplicity, safety and lower probability of internal hernia;(2) stable and durable weight reduction effect; (3) stable and durable remission rate of type 2 Diabetes. The disadvantages of OAGB/MGB include: (1) bile reflux; (2) higher risk of malnutrition. OAGB/MGB has achieved a good balance between effectiveness and safety, and has become the most noticed and fastest-growing bariatric and metabolic procedure in recent years. OAGB/MGB has been recommended as a standard bariatric and metabolic procedure by IFSO and ASMBS.

Biliary reflux resistant to medical treatment has an incidence of 0.6-10% after one anastomosis gastric bypass (OAGB) and may be a reason for revisional surgery. The aim of this study is to report the results of a single-institution series of patients who underwent conversion from OAGB to Roux-en-Y gastric bypass (RYGB) for biliary reflux. Data of OAGB patients converted to RYGB between May 2010 and December 2017 were prospectively collected and retrospectively analyzed. The afferent limb was sectioned proximally to the gastrojejunal anastomosis. A jejuno-jejunal latero-lateral anastomosis was performed between the biliary and alimentary limb. The final RYGB had an alimentary limb of 100cm and a biliary limb of 150cm. During the study period, 2780 patients underwent OAGB. A total of 32 patients (1.2%) underwent conversion from OAGB to RYGB for biliary reflux, at a mean of 30.3months from OAGB. Mean weight before RYGB was 70.6kg, and mean body mass index BMI was 26kg/m2. Four patients experienced postoperative complications (12.5%). Patients' mean weight was 74.3kg at 24months follow-up, with BMI of 27.2kg/m2. Conversion to RYGB relieved symptoms of biliary reflux in all patients but 2 (93.8%). Biliary reflux although rare can complicate OAGB. RYGB is a safe and feasible technique of revision in this case. A shorter length of the afferent limb during the initial operation facilitates the revision.

Reoperations due to failures constitute an essential but challenging part of bariatric surgery practice today. The aim of this study was to evaluate the perioperative safety, efficacy, and postoperative quality of life in patients with biliopancreatic diversion (BPD), after failed vertical banded gastroplasty (VBG). Twelve patients after failed or complicated VBG, eight females and four males, median age 45 years (range 39-52), median body mass index (BMI) 46.39 kg/m2 (range 25.89-69.37), who underwent conversion to BPD, were studied. Ten patients due to weight regain and two patients because of severe stenosis of the gastric pouch outlet were submitted in conversion to BPD. In eight (66.6%) patients the primary VBG had been followed by at least one revisional operation due to inadequate weight loss. The 10 patients after failed VBG, reached the lowest BMI recorded after VBG in just a year after BPD (p=0.721 for the comparison between the two time points). The two patients with stomal stenosis regained weight in the first six postoperative months and remain stable since then. Regarding safety, one major perioperative complication (gastrojejunostomy stenosis) occurred. At a median follow-up of 21 months (range 12-30) six complications have been documented, including a case of incisional hernia, four cases of pouch gastritis and a case of intractable iron-deficiency anemia. Our early results indicate that conversion of failed VBG to BPD is highly effective with acceptable morbidity. Our data show that the effect on weight is strongly dependent on the indication for the conversion. Conversion to BPD, in such a group of patients, is a wise alternative, since it may reduce operative risks.