Banded One-Anastomosis Gastric Bypass (BOAGB) for Patients Living with Obesity and Extreme Obesity: A Single Institution's Experience

BACKGROUND

The prevalence of patients suffering from extreme obesity (body mass index (BMI) ≥ 50) has significantly increased over the past three decades, surpassing the rise in the general population of overweight patients. Weight loss outcomes after bariatric surgery in patients suffering from extreme obesity are less favorable, with a higher incidence of weight regain. Variations of existing bariatric procedures have been proposed to address this issue. One such variation is adding a gastric band to limit the expansion of the newly created pouch. Limited data exist regarding the effectiveness of this procedure, called the banded one-anastomosis gastric bypass (BOAGB) procedure, compared to other bariatric procedures.

METHOD

In this retrospective study, we compared all patients who underwent the BOAGB procedure at the Bariatric Surgery Unit in our Medical Center with a postoperative follow-up of at least 1 year with patients who underwent a one-anastomosis gastric bypass (OAGB) or sleeve gastrectomy (SG) procedures. Data collected included demographics, comorbidities, surgical outcomes, complications, and postoperative quality-of-life assessments.

RESULTS

One hundred eleven patients were enlisted to our study during the relevant study period-24 patients underwent the BOAGB procedure, 43 underwent OAGB, and 44 underwent a SG. Lost to follow-up beyond 30 days was 9% (at 1-year post-surgery, we were able to establish contact with 101 patients). The pre-op BMI was significantly higher in the BOAGB group compared to the other procedures. Additionally, a higher prevalence of diabetes was observed in the BOAGB group. The duration of surgery was significantly longer for the BOAGB procedure. No significant differences were found in surgical complications. Overall, all procedures resulted in significant excess weight loss (EWL) or change in BMI, improvement in comorbidities, and improved quality of life postoperatively.

CONCLUSIONS

The BOAGB procedure, like OAGB and SG, demonstrated favorable weight loss outcomes and weight maintenance 1 year postoperatively without significant differences between the procedures. The BOAGB procedure is relatively new, with good bariatric outcomes and a favorable safety profile. Long-term study is needed to evaluate these various bariatric procedures' efficacy further.

Technical Variations and Considerations around OAGB in IFSO-APC and IFSO-MENAC Chapters, an Expert Survey

OBJECTIVE

This study aimed to evaluate the technical variations of one-anastomosis gastric bypass (OAGB) among IFSO-APC and MENAC experts.

BACKGROUND

The multitude of technical variations and patient selection challenges among metabolic and bariatric surgeons worldwide necessitates a heightened awareness of these issues. Understanding different perspectives and viewpoints can empower surgeons performing OAGB to adapt their techniques, leading to improved outcomes and reduced complications.

METHODS

The scientific team of IFSO-APC, consisting of skilled bariatric and metabolic surgeons specializing in OAGB, conducted a confidential online survey. The survey aimed to assess technical variations and considerations related to OAGB within the IFSO-APC and IFSO-MENAC chapters. A total of 85 OAGB experts participated in the survey, providing their responses through a 35-question online format. The survey took place from January 1, 2024, to February 15, 2024.

RESULTS

Most experts do not perform OAGB for children and adolescents younger than 18 years. Most experts create the gastric pouch over a 36-40-F bougie and prefer to create a gastrojejunostomy, at the posterior wall of the gastric pouch. An anti-reflux suture during OAGB is performed in all patients by 51.8% of experts. Most experts set a common limb length of > 4 m in revisional and conversional OAGBs to prevent nutritional complications.

CONCLUSION

The ongoing debate among metabolic and bariatric surgeons regarding the technical variations and patient selection in OAGB remains a significant point of discussion. This survey demonstrated the variations in technical aspects and patient selection for OAGB among MBS surgeons in the IFSO-APC and IFSO-MENAC chapters. Standardizing the OAGB technique is crucial to ensure optimal safety and efficacy in this procedure.

American Society for Metabolic and Bariatric Surgery position statement on one-anastomosis gastric bypass

The following position statement is issued by the American Society for Metabolic and Bariatric Surgery in response to inquiries made to the society by patients, physicians, society members, hospitals, health insurance payors, and others regarding one-anastomosis gastric bypass as a treatment for obesity and metabolic disease. This statement is based on current clinical knowledge, expert opinion, and published peer-reviewed scientific evidence available at this time. The statement may be revised in the future as more information becomes available.

Conversion of one-anastomosis gastric bypass (OAGB) to Roux-en-Y gastric bypass (RYGB) for gastroesophageal reflux disease (GERD): who is more at risk? A multicenter study

BACKGROUND

Although gastroesophageal reflux disease (GERD) affects 0.6% to 10% of patients operated on for one-anastomosis gastric bypass (OAGB), only about 1% require surgery to convert to Roux-en-Y gastric bypass (RYGB) [3-5]. The aim of the present study was to analyze the characteristics of OAGB patients converted to RYGB for GERD not responding to medical treatment.

METHODS

This retrospective multicenter study included patients who underwent conversion from OAGB to RYGB for severe GERD. The conversion was performed with resection of the previous gastro-jejunal anastomosis and the use of the afferent loop as a new biliary loop.

RESULTS

A total of 126 patients were included in the study. Of these patients, 66 (52.6%) had a past medical history of bariatric restrictive surgery (gastric banding, sleeve gastrectomy). A hiatal hernia (HH) was present in 56 patients (44.7%). The association between previous restrictive surgery and HH was recorded in 33 (26.2%) patients. Three-dimensional gastric computed tomography showed an average gastric pouch volume of 242.4 ± 55.1 cm3. Conversion to RYGB was performed on average 60 ± 35.6 months after OAGB. Seven patients (5.5%) experienced an early postoperative complication (4 patients grade IIIb and 3 grade IIb), and 3 (2.4%) a late complication. Patients showed further weight loss after RYGB conversion and an average of 24.8 ± 21.7 months after surgery, with a mean % of total weight loss (%TWL) of 6.9 ± 13.6 kg. From a clinical point of view, the problem of GERD was definitively solved in more than 90% of patients.

CONCLUSIONS

Situations that weaken the esogastric junction appear to be highly frequent in patients operated on for OAGB and converted to RYGB for severe reflux. Similarly, the correct creation of the gastric pouch could play an important role in reducing the risk of conversion to RYGB for GERD.

Outcomes of Laparoscopic Sleeve Gastrectomy (LSG) vs One-Anastomosis Gastric Bypass (OAGB) in Patients with Super-Super Obesity (BMI ≥ 60 kg/m2)

INTRODUCTION

The data comparing laparoscopic sleeve gastrectomy (LSG) and one-anastomosis gastric bypass (OAGB) in patients with BMI ≥ 60 kg/m2 is scarce.

METHODS

Prospectively collected data of patients with BMI ≥ 60 kg/m2 undergoing LSG or OAGB from January 2008 until June 2022 was analyzed retrospectively. Weight loss outcomes, impact on comorbidities, and complications were compared in both groups.

RESULTS

Fifty-six patients underwent LSG and 13 patients underwent OAGB. The median age and BMI were 37 (34-44) years and 63 (61.3-64.6) kg/m2 respectively. Both the groups had similar baseline demographic parameters. The percentage excess BMI loss (%EBMIL) was statistically similar in LSG and OAGB groups at 1 year (46.2% vs 46.1%), 3 years (52.9% vs 56.7%), and 5 years (51.1% vs 62.3%). The percentage excess BMI regain was lower (although statistically similar) following OAGB at 3 years (5.3% vs 0.1%) and 5 years (12.9% vs 4.4%). OAGB was found to correlate positively with weight loss and negatively with weight regain (p > 0.05). There was one 30-day mortality due to postoperative lower respiratory infection in the LSG group.

CONCLUSION

OAGB has a trend towards better weight loss outcomes as compared to LSG in patients with a BMI ≥ 60 kg/m2 with lesser complication rates and might be a preferred option. LSG also has acceptable weight loss and should be considered a standalone procedure if OAGB is not feasible technically.

Management of Leak by Intraoperative Megastent Insertion During Revisional Bariatric Metabolic Surgery: a Case Report

We describe gastric tube continuity restoration (gastrogastrostomy) in a patient who underwent revisional laparoscopic one-anastomosis gastric bypass (OAGB) due to weight recurrence after laparoscopic sleeve gastrectomy (SG). The patient sought restoration to SG due to poor quality of life. A postoperative 11-mm leak at the site of the gastrogastrostomy, attributed to adhesions and edema from a marginal ulcer, complicated the procedure. As a result, laparoscopic exploration was performed, followed by insertion of a megastent. We hereby present video documentation of this case report as well as megastent insertion technique for the treatment of such complications.

Early outcomes of one-anastomosis gastric bypass in the elderly population at high-volume bariatric centers

The increasing rate of obesity and life expectancy will lead to increasing numbers of bariatric procedures in the elderly. We aim to report the early (≤ 30 days) adverse events of One-Anastomosis Gastric Bypass (OAGB) in this patient population. Assuta Bariatric Centers in Israel. Retrospective review of perioperative OAGB outcomes between elderly group (≥ 65 years) and non-elderly group (18-64 years) at high-volume bariatric centers between January 2017-December 2021. Operative time, length of stay (LOS), and overall ≤ 30 days complication rates, as ranked by the Clavien-Dindo Classification (CDC) were compared. There were 6618 patients (non-elderly group) and 104 (elderly group) who underwent OAGB. Gender and preoperative BMI were comparable between the two age groups. The elderly group had significantly higher rate of ischemic heart disease and chronic renal failure. The number of patients with LOS ≥ 3 days was significantly higher in the elderly group [19.4% (n = 20) vs. 6.6% (n = 331), respectively; p < 0.001]. The total early adverse events were higher in the elderly group with no statistical significance [7.7% (n = 8) vs. 3.8% (n = 250), respectively; p = 0.062]. The rate of minor and major adverse events and reoperation rate was comparable between the two groups. The rate of readmissions was significantly higher in the elderly group 5.8% (n = 6) vs. 1.9% (n = 124), respectively p = 0.015. There was 0.06% mortality (n = 2) in the non-elderly group. OAGB is a relatively safe metabolic and bariatric surgery for elderly obese patients with early (≤ 30 days) morbidity rates similar to the non-elderly population.

Malnutrition Following One-Anastomosis Gastric Bypass: a Systematic Review

Severe malnutrition following one-anastomosis gastric bypass (OAGB) remains a concern. Fifty studies involving 49,991 patients were included in this review. In-hospital treatment for severe malnutrition was needed for 0.9% (n = 446) of patients. Biliopancreatic limb (BPL) length was 150 cm in five (1.1%) patients, > 150 cm in 151 (33.9%), and not reported in 290 (65%) patients. OAGB was revised to normal anatomy in 126 (28.2%), sleeve gastrectomy in 46 (10.3%), Roux-en-Y gastric bypass in 41 (9.2%), and shortening of BPL length in 17 (3.8%) patients. One hundred fifty-one (33.8%) patients responded to treatment; ten (2.2%) did not respond and was not reported in 285 (63.9%) patients. Eight (0.02%) deaths were reported. Standardisation of the OAGB technique along with robust prospective data collection is required to understand this serious problem.

Does One-Anastomosis Gastric Bypass Expose Patients to Gastroesophageal Reflux: a Systematic Review and Meta-analysis

This systematic review and meta-analysis aimed to investigate the incidence of new-onset gastroesophageal reflux, reflux change, esophagitis, Barrett's esophagus, and revision due to reflux, gastritis, and marginal ulcer after one-anastomosis gastric bypass (OAGB). We performed subgroup analyses based on primary and revisional OAGB and time of follow-up. Meta-analysis of 87 studies with 27,775 patients showed a 6% rate of new-onset reflux after OAGB. Preoperative reflux status did not change significantly after OAGB. The rate of esophagitis and Barrett's esophagus was 15% and 1%, respectively. The new-onset reflux rate after OAGB was significantly higher than gastric bypass but not different with sleeve gastrectomy. The current study showed a relatively low rate of reflux and its complications after OAGB, but it was significantly higher than Roux-en-Y gastric bypass.

One-anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) as revisional procedures after failed laparoscopic sleeve gastrectomy (LSG): systematic review and meta-analysis of comparative studies

INTRODUCTION

The aim of this study was to compare weight loss and gastroesophageal reflux disease (GERD) remission after one-anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) as revisional procedures after laparoscopic sleeve gastrectomy (LSG).

METHODS

In PubMed, Embase, and Cochrane Library, a search was performed using the terms "Roux-en-Y gastric bypass versus one anastomosis gastric bypass," "revisional surgery," and "sleeve gastrectomy." Only original articles in English language comparing OAGB and RYGB were included. No temporal interval was set. The primary outcome measure was weight loss (%TWL). The secondary endpoints were leak, bleeding, marginal ulcer, and GERD. PRISMA flowchart was used. Differences in continuous and dichotomous outcome variables were expressed as mean difference (MD) and risk difference (RD) with 95% CI, respectively. Heterogeneity was assessed by using I2 statistic.

RESULTS

Six retrospective comparative articles were included in the present meta-analysis. Weight loss analysis showed a MD = 5.70 (95% CI 4.84-6.57) in favor of the OAGB procedure with a statistical significance (p = 0.00001) and no significant statistical heterogeneity (I2 = 0.00%). There was no significant RD for leak, bleeding, or marginal ulcer after the two revisional procedures. After conversion to OAGB, remission from GERD was 68.6% (81/118), and it was 80.6% (150/186) after conversion to RYGB with a RD = 0.10 (95% CI -0.04, 0.24), no statistical significance (p = 0.19), and high heterogeneity (I2 = 96%). De novo GERD was 6.3% (16/255) after conversional OAGB, and it was 0.5% (1/180) after conversion to RYGB with a RD = -0.23 (95% CI -0.57, 0.11), no statistical significance (p = 0.16), and high heterogeneity (I2 = 92%).

Markers for Major Complications at Day-One Postoperative in Fast-Track Metabolic Surgery: Updated Metabolic Checklist

INTRODUCTION

In fast-track metabolic surgery, the window to identify complications is narrow. Postoperative checklists can be useful tools in the decision-making of safe early discharge. The aim of this study was to evaluate the predictive value of a checklist used in metabolic surgery.

METHODS

Retrospective data from June 2018 to January 2021 was collected on all patients that underwent metabolic surgery in a high-volume bariatric hospital in the Netherlands. Patients without an available checklist were excluded. The primary outcome was major complications and the secondary outcomes were minor complications, readmission, and unplanned hospital visits within 30 days postoperatively.

RESULTS

Major complications within 30 days postoperatively occurred in 62/1589 (3.9%) of the total included patients. An advise against early discharge was significantly more seen in patients with major complications compared to those without major complications (90.3% versus 48.1%, P < 0.001, respectively), and a negative checklist (advice for discharge) had a negative predictive value of 99.2%. The area under the curve for the total checklist was 0.80 (P < 0.001). Using a cut-off value of ≥3 positive points, the sensitivity and specificity were 65% and 82%, respectively. Individual parameters from the checklist: oral intake, mobilization, calf pain, willingness for discharge, heart rate, drain (>30 ml/24 h), hemoglobin, and leukocytes count were also significantly different between groups.

CONCLUSION

This checklist is a valuable tool to decide whether patients can be safely discharged early. Heart rate appeared to be the most predictive parameter for the development of major complications. Future studies should conduct prediction models to identify patients at risk for major complications.

A narrative review

One-anastomosis gastric bypass has now become the third most commonly performed bariatric technique worldwide. However, as a consequence of the configuration of this surgery, it can present some chronic complications (anastomotic mouth ulcers and biliary reflux) that physicians must come to better understand and assess. In this narrative review, we aimed to update our knowledge of both the diagnosis and treatment of these two complications in the context of bariatric surgeries. We concluded that a series of pre-, intra-, and postoperative preventive strategies should be considered by surgeons to help reduce the appearance of these complications.

Roux-en-Y and One-Anastomosis Gastric Bypass Surgery Are Superior to Sleeve Gastrectomy in Lowering Glucose and Cholesterol Levels Independent of Weight Loss: a Propensity-Score Weighting Analysis

BACKGROUND

The superior effects of gastric bypass surgery in preventing cardiovascular diseases compared with sleeve gastrectomy are well-established. However, whether these effects are independent of weight loss is not known.

METHODS

In this retrospective cohort study, we compared the change in cardiometabolic risks of 1073 diabetic patients undergoing Roux-en-Y gastric bypass (RYGB) (n = 265), one-anastomosis gastric bypass (OAGB) (n = 619), and sleeve gastrectomy (SG) (n = 189) with equivalent weight loss from the Min-Shen General Hospital. Propensity score-weighting, multivariate regression, and matching were performed to adjust for baseline differences.

RESULTS

After 12 months, OAGB and, to a lesser extent, RYGB exhibited superior effects on glycemic control compared with SG in patients with equivalent weight loss. The effect was significant in patients with mild-to-modest BMI reduction but diminished in patients with severe BMI reduction. RYGB and OAGB had significantly greater effects in lowering total and low-density lipoprotein cholesterol than SG, regardless of weight loss. The results of matching patients with equivalent weight loss yielded similar results. The longer length of bypassed biliopancreatic (BP) limbs was correlated with a greater decrease in glycemic levels, insulin resistance index, lipids, C-reactive protein (CRP) levels, and creatinine levels in patients receiving RYBG. It was correlated with greater decreases in BMI, fasting insulin, insulin resistance index, and C-reactive protein levels in patients receiving OAGB.

CONCLUSION

Diabetic patients receiving OAGB and RYGB had lower glucose and cholesterol levels compared with SG independent of weight loss. Our results suggest diabetic patients with cardiovascular risk factors such as hypercholesterolemia to receive bypass surgery.

Adenocarcinoma of the Gastro-jejunal Anastomosis After One Anastomosis Gastric Bypass

INTRODUCTION

One anastomosis gastric bypass (OAGB) is mainly criticized for the supposed carcinogenic effect of bile reflux on the gastric pouch mucosa.

CASE PRESENTATION

A 56-year-old male patient presented 12 years after OAGB with a 10-month history of gradual dysphagia and vomiting. He was diagnosed with a tumor of the gastro-jejunal anastomosis, and underwent total gastrectomy with D2 lymphadenectomy. Specimen examination showed a diffuse isolated cell-type adenocarcinoma. To our knowledge, we report the first case in literature of adenocarcinoma of the gastro-jejunal anastomosis post-OAGB, and the second reported case if we include the Mason loop gastric bypass, which was the earlier version of OAGB with a different conceptual and physiological aspect.

CONCLUSION

The carcinogenic effect of bile reflux in OAGB will remain hypothetical until a detailed controlled study may prove the causality between bile reflux and gastric pouch malignancies in patients with a history of OAGB.

[Anastomotic techniques in minimally invasive bariatric surgery]

BACKGROUND

Recommendations for the use of specific anastomotic techniques are not available in laparoscopic bariatric surgery. Recommendation criteria should consider the rate of insufficiency, bleeding, tendency to stricture or ulceration as well as the impact on weight loss or dumping.

OBJECTIVE

This article gives a review of the available evidence on the anastomotic techniques of typical surgical procedures in laparoscopic bariatric surgery.

MATERIAL AND METHODS

The current literature was reviewed and is discussed regarding anastomotic techniques for Roux-en‑Y gastric bypass (RYGB), one-anastomosis gastric bypass (OAGB), single anastomosis sleeve ileal (SASI) bypass and biliopancreatic diversion with duodenal switch (BPD-DS).

RESULTS

Few comparative studies exist, except for the RYGB. In RYGB gastrojejunostomy, a complete manual suture was shown to be equivalent to a mechanical anastomosis. In addition, the linear staple suture showed slight advantages over the circular stapler in terms of wound infections and bleeding. The anastomosis technique of the OAGB and SASI can be performed entirely with a linear stapler or with suture closure of the anterior wall defect. There seems to be an advantage of manual anastomosis in BPD-DS.

CONCLUSION

Due to the lack of evidence, no recommendations can be made. Only in RYGB was there an advantage of the linear stapler technique with hand closure of the stapler defect compared to the linear stapler. In principle, prospective, randomized studies should be strived for.

Are male patients undergoing bariatric surgery less healthy than female patients?

BACKGROUND

Male patients are underrepresented in bariatric surgery (BS) despite a relatively equal proportion of men and women experiencing obesity.

OBJECTIVES

Differences in frequency and severity of obesity-associated medical problems (OAMPs) between men and women undergoing BS or in a control group (HELIUS [HEalthy Life In an Urban Setting]) were evaluated. The hypothesis was that men undergoing BS are less healthy than women.

SETTING

A cross-sectional study of 2 cohorts undergoing BS in 2013 (BS2013) and 2019 (BS2019) and a control group of patients with severe obesity from a general population (HELIUS).

METHODS

Characteristics concerning weight and OAMPs, medication usage, intoxications, postoperative complications (for BS2019) were compared between men and women. Members of the HELIUS cohort were tested for eligibility for BS.

RESULTS

Of 3244 patients included, the majority were female (>78.4%). Median (interquartile range) age and body mass index (kg/m2) in male versus female patients were 47.0 (41.0-53.8) versus 43.0 (36.0-51.0) years and 41.5 (38.4-45.2) versus 42.3 (40.2-45.9), respectively, in BS2013, and 52.0 (39.8-57.0) versus 45.0 (35.0-53.0) years and 40.4 (37.4-43.8) versus 41.3 (39.0-44.1) in BS2019 (P < .05). The rates of men with OAMPs were 71.4% and 82.0% compared with 50.2% and 56.9% of women in BS2013 and BS2019, respectively. Overall medication usage was higher in male patients (P = .014). In BS2019, male patients exhibited a higher median HbA1C (P < .001) and blood pressure (P = .003) and used more antihypertensives and antidiabetics (P = .004). Postoperative complications did not differ between men and women. In the control cohort, 66.5% of men and 66.6% of women were eligible for BS.

CONCLUSION

Men undergoing BS more often experience OAMPs than women, and OAMPs are more advanced in men.

Marginal Ulcers Following One-Anastomosis Gastric Bypass: a Systematic Review and Meta-analysis

BACKGROUND

Marginal ulcer (MU) is an uncommon but significant complication following one-anastomosis gastric bypass (OAGB). Our study aims to understand the incidence rates, risk factors, and management of MU following OAGB.

METHODS

MEDLINE, Scopus, and Cochrane Library databases were examined to identify all studies on OAGB where authors had reported on MU. Data were collected on basic demographics, incidence rates, risk factors, and management of this condition.

RESULTS

Thirty-two studies involving 8868 patients were analysed. The mean age and body mass index (BMI) of patients in these studies were 40.9 ± 4.5 years and 47.6 ± 5.6 kg/m2, respectively. Among the patient cohort, approximately 72% were female, and 20.6% had preoperative gastroesophageal reflux disease (GERD). The authors described prescribing proton-pump inhibitors (PPI) prophylaxis to 14.1% of patients after surgery. Two hundred twenty-eight patients were reported to have MU. The incidence of MU was 2.59% (95% CI 1.89-3.52), of which 53 patients presented within 12 months, 24 patients presented after 31 months, and five patients after 6 years. One hundred forty-six patients did not have presentation time documented. Sixty-five patients were described to have MU diagnosed on endoscopy, of which 54 were symptomatic and 11 were asymptomatic. The authors were, however, not specific on the choice of investigation for the remaining 163 patients. Of patients, 89.7% were treated conservatively with PPIs, whilst 10.3% had surgery to treat MU.

CONCLUSIONS

Marginal ulcer is an uncommon complication following OAGB. The majority of patients are treated conservatively with PPIs. Larger, well-designed studies reporting on risk factors, investigation, and management of MU following OAGB are warranted.

The male patient with obesity undergoing metabolic and bariatric surgery: changes in testosterone levels correlate with weight loss after one-anastomosis gastric bypass and Roux-en-Y gastric bypass

BACKGROUND

Male obesity secondary hypogonadism (MOSH) is a common disease among men with obesity and can be associated with metabolic syndrome and a variety of metabolic problems ultimately leading to androgen deficiency. Metabolic and bariatric surgery is a well-established treatment option associated with significant weight loss and reduction in metabolic co-morbidities.

OBJECTIVES

To evaluate the impact of surgery on plasma levels of sexual hormones and their effect on weight loss comparing 2 surgical methods (one-anastomosis gastric bypass [OAGB] and Roux-en-Y gastric bypass [RYGB]) in male patients with obesity.

SETTING

University hospital, Austria.

METHODS

Patients undergoing OAGB and RYGB between 2012 and 2017 were analyzed retrospectively. Follow-up in this study was up to 24 months. Systemic levels of sexual hormones (luteinizing hormone [LH]), follicle stimulating hormone [FSH], total testosterone [TT], sexual hormone binding globin [SHBG], 17 beta-estradiol [17bE], androstenedione [AS]) were retrieved at each visit. A linear mixed model was used to assess the correlation between changes in testosterone levels and percent excess weight loss (%EWL).

RESULTS

In 30.8% of all patients, MOSH was present preoperatively. A significant increase of TT was observed postoperatively that led to a complete resolution of hypogonadism within the period observed. Bioavailable testosterone (bTT) and FSH levels significantly increased each month of follow-up after surgery (all P < .01). Levels of 17bE did not change significantly after surgery. The overall change of TT, comparing preoperative and 1-year postoperative TT levels (ΔTT), significantly correlated with %EWL. Changes in TT levels were not affected by the choice of surgical method.

CONCLUSIONS

Serum plasma testosterone levels rise significantly after metabolic and bariatric surgery in male patients. The change of testosterone levels seems to play a role in continued weight loss after surgery. This is true irrespective of the surgical method used.

A Randomized Controlled Trial of Acid and Bile Reflux Esophagitis Prevention by Modified Fundoplication of the Excluded Stomach in One-Anastomosis Gastric Bypass: 1-Year Results of the FundoRing Trial

BACKGROUND

The advantages and disadvantages of one-anastomosis gastric bypass (OAGB) with primary modified fundoplication using the excluded stomach ("FundoRing") is unclear. We aimed to assess the impact of this operation in a randomized controlled trial (RCT) and answer the next questions: (1) What the impact of wrapping the fundus of the excluded part of the stomach in OAGB on protection in the experimental group against developing de novo reflux esophagitis? (2) If preoperative RE could be improved in the experimental group? (3) Can preoperative acid reflux as measured by PH impedance, be treated by the addition of the "FundoRing"?

METHODS

The study design was a single-center prospective, interventional, open-label (no masking) RCT (FundoRing Trial) with 1-year follow-up. Endpoints were body mass index (BMI, kg/m2) and acid and bile RE assessed endoscopically by Los Angeles (LA) classification and 24-h pH impedance monitoring. Complications were graded by Clavien-Dindo classification (CDC).

RESULTS

One hundred patients (n = 50 FundoRingOAGB (f-OAGB) vs n = 50 standard OAGB (s-OAGB)) with complete follow-up data were included in the study. During OAGB procedures, patients with hiatal hernia underwent cruroplasty (29/50 f-OAGB; 24/50 s-OAGB). There were no leaks, bleeding, or deaths in either group. At 1 year, BMI in the f-OAGB group was 25.3 ± 2.77 (19-30) vs 26.48 ± 2.8 (21-34) s-OAGB group (p = 0.03). In f-OAGB vs s-OAGB groups, respectively, acid RE was seen in 1 vs 12 patients (p = 0.001) and bile RE in 0 vs 4 patients (p < 0.05).

CONCLUSION

Routine use of a modified fundoplication of the OAGB-excluded stomach to treat patients with obesity decreased acid and prevented bile reflux esophagitis significantly more effectively than standard OAGB at 1 year in a randomized controlled trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04834635.

Clinical influence of conversion of laparoscopic sleeve gastrectomy to one anastomosis gastric bypass on gastroesophageal reflux disease

PURPOSE

Assess the subjective impact of gastro-esophageal reflux disease (GERD) symptoms on patients undergoing revision from laparoscopic sleeve gastrectomy (LSG) to one-anastomosis gastric bypass (OAGB) using the Reflux Disease Questionnaire for GERD (RDQ) and the GERD-health related quality of life score (GERD-HRQL), prior to- and following conversion.

METHODS

Patients undergoing revision from LSG to OAGB were prospectively followed between May 2015 and December 2020. Data retrieved included demographics, anthropometrics, previous bariatric history, time interval between LSG and OAGB, weight loss, and co-morbidities. Pre- and post-OAGB RDQ and GERD-HRQL questionnaires were obtained. In the case of sleeve dilatation, sleeve resizing was performed.

RESULTS

During the study period, 37 patients underwent revision from LSG to OAGB. Mean ages at LSG and pre-OAGB were 38 ± 11.74 and 46 ± 12.75, respectively. Median follow-up time was 21.5 months (range 3-65). All patients underwent sleeve resizing. RDQ and GERD-HRQL scores were obtained at a median of 14 months (range 3-51) between pre- and post-OAGB. Median RDQ score pre-OAGB vs post-OAGB was significantly reduced (30 (range 12-72) vs 14 (range 12-60), p = 0.007). All 3 parts of the GERD- HRQL questionnaires were significantly reduced between pre-OAGB and post-OAGB: Symptoms (20; 62.5% vs 10; 31.3%, p = 0.012), overall score (15 (0-39) vs 7 (0-28), p = 0.04) and subjective improvement (10; 31% vs 20; 62.5%, p = 0.025).

CONCLUSION

Conversion of LSG to OAGB showed subjective improvement of GERD symptoms both in RDQ and in GERD-HRQL.

Comparison of hypertension remission and relapse after sleeve gastrectomy and one-anastomosis gastric bypass: a prospective cohort study

This study aimed to assess the remission and relapse of hypertension (HTN) in hypertensive individuals who underwent sleeve gastrectomy (SG) and one-anastomosis gastric bypass (OAGB) and identify the predictors of HTN remission and relapse following bariatric surgery. A prospective cohort study with a follow-up of 3 years was conducted on severely obese patients between 2013 and 2018. Hypertension remission was defined as the normalization of blood pressure (BP) with the discontinuation of medical treatment, and HTN relapse was defined as the need for the onset of antihypertensive drugs or the occurrence of BP impairment. A total of 787 hypertensive patients were included in this study. The cumulative incidence of HTN remission and relapse were 83.9% (95% CI: 81.6-86.5) and 31.4% (95% CI: 25.6-38.2), respectively. Remission and relapse were not significantly different among the patients undergoing either surgery (SG or OAGB). A higher remission rate was linked to a younger age and the use of fewer antihypertensive medications pre-operation. However, failure to successfully lose weight during the first year postoperative and weight regain predicted a higher risk of HTN relapse after 3 years. Following bariatric surgery, BP drops initially but then gradually rises. These alterations are responsible for about 31% relapse after 3 years in those who initially achieve remission. Patients who are younger and use less antihypertensive medications before surgery may benefit the most from bariatric surgery in terms of HTN. First-year successful weight loss and control of weight regain may prevent HTN relapse in the following years.

Intrathoracic pouch migration in one-anastomosis gastric bypass with and without hiatoplasty: A 3-dimensional-computed tomography volumetry study

BACKGROUND

Currently, 4.8% of bariatric operations worldwide are one-anastomosis gastric bypass (OAGB) procedures. If a hiatal hernia is detected in a preoperative gastroscopy, OAGB can be combined with hiatoplasty. Intrathoracic pouch migration (ITM) is common after bypass procedures because the fundus, a natural abutment, is separated from the pouch.

OBJECTIVE

The aim of this study was to find out whether OAGB or OAGB combined with hiatoplasty carries a higher risk of ITM and, therefore, also gastroesophageal reflux disease (GERD).

SETTING

University hospital.

METHODS

Fifty patients (group 1: 25× primary OAGB; group 2: 25× primary OAGB with hiatoplasty) were included in this study. History of weight, GERD, and quality of life were recorded in patient interviews and pouch volume and ITM were evaluated using 3-dimensional-computed tomography volumetry.

RESULTS

There were no differences in terms of patient characteristics, history of weight, pouch volume, or quality of life between both groups. ITM was found in group 1 in 60% (n = 15) and group 2 in 76% (n = 19) of all patients (P = .152). The ITM mean length was significantly lower in group 1 with .9 ± 1.1 cm than in group 2 with 1.8 ± 1.2 cm (P = .007). Regarding GERD, there was no difference between both groups; nevertheless, significantly more patients with ITM (38.2%; n = 13) had GERD compared with patients without ITM (6.3%; n = 1).

CONCLUSION

In primary OAGB, an additional hiatoplasty was not associated with higher rates of ITM or GERD; nevertheless, the length of ITM was higher after hiatoplasty. If ITM occurs, patients have a risk of developing GERD.

The effects of laparoscopic Roux-en-Y gastric bypass and one-anastomosis gastric bypass on glycemic control and remission of type 2 diabetes mellitus: study protocol for a multi-center randomized controlled trial (the DIABAR-trial)

Background

Metabolic surgery induces rapid remission of type 2 diabetes mellitus (T2DM). There is a paucity of high level evidence comparing the efficacy of the laparoscopic Roux-en-Y gastric bypass (RYGB) and the laparoscopic one-anastomosis gastric bypass (OAGB) in glycemic control. Also, the mechanisms that drive the conversion of T2DM in severe obese subjects to euglycemia are poorly understood.

Methods

The DIABAR-trial is an open, multi-center, randomized controlled clinical trial with 10 years follow-up which will be performed in 220 severely obese patients, diagnosed with T2DM and treated with glucose-lowering agents. Patients will be randomized in a 1:1 ratio to undergo RYGB or OAGB. The primary outcome is glycemic control at 12 months follow-up. Secondary outcome measures are diverse and include weight loss, surgical complications, psychologic status and quality of life, dietary behavior, gastrointestinal symptoms, repetitive bloodwork to identify changes over time, glucose tolerance and insulin sensitivity as measured by mixed meal tests, remission of T2DM, presence of non-alcoholic fatty liver disease/non-alcoholic steatohepatitis in liver biopsy, oral and fecal microbiome, cardiovascular performance, composition of bile acids, and the tendency to develop gallstones.

Discussion

The DIABAR-trial is one of the few randomized controlled trials primarily aimed to evaluate the glycemic response after the RYGB and OAGB in severe obese patients diagnosed with T2DM. Secondary aims of the trial are to contribute to a deeper understanding of the mechanisms that drive the remission of T2DM in severe obese patients by identification of microbial, immunological, and metabolic markers for metabolic response and to compare complications and side effects of RYGB and OAGB.

Trial registration

ClinicalTrials.gov NCT03330756; date first registered: October 13, 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06762-3.

Small Intestinal Bacterial Overgrowth in Patients with Roux-en-Y Gastric Bypass and One-Anastomosis Gastric Bypass

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) is defined as an excessive growth and/or changed composition of bacteria in the small bowel. Obese patients are at increased risk of SIBO and related complications. The purpose of this study is to evaluate the incidence of SIBO after bariatric bypass procedures, connection between SIBO, symptoms, comorbidities, and liver pathology.

METHODS

Patients underwent a hydrogen breath test with glucose substrate (25 g/200 ml of water). The demographic, anthropometric data, comorbidities, and symptoms were analysed with a questionnaire. In 45 patients, the NAFLD Activity Score was evaluated in liver biopsies.

RESULTS

Glucose breath test was positive in 24/56 (43%) of patients and was associated with higher frequency of defecation (p = 0.022), lactose intolerance (p = 0.047), scleroderma (p = 0.042), irritable bowel syndrome (p = 0.018), and diabetes (p = 0.002). Mean NAFLD Activity Score in SIBO patients (n = 18) was 3.33 and 3.00 in non-SIBO patients (n = 27). In SIBO-positive cohort of patients, a statistically important trend in difference between NAS and difference to range value anti-Xa 4 h after subtherapeutic dose application was calculated.

CONCLUSIONS

The incidence of SIBO after bariatric surgery bypass procedures is alarmingly high (43%). The results of our study conclude that diagnosis cannot be set based on specific symptom and SIBO is related to reduced response to the application of LMWH. Mandatory SIBO screening and appropriate treatment would affect the clinical outcome of the underlying disease, improve it significantly, and prevent the development of its complications.

Ten-year outcome of one-anastomosis gastric bypass with a biliopancreatic limb of 150 cm versus Roux-en-Y gastric bypass: a single-institution series of 940 patients

BACKGROUND

Long-term outcomes of one-anastomosis gastric bypass (OAGB) need to be compared with those of Roux-en-Y gastric bypass (RYGB).

OBJECTIVE

The present study evaluates the long-term outcomes at 10-year follow-up of OAGB with a biliopancreatic limb of 150 cm versus RYGB.

SETTING

Private practice, France.

METHODS

Data of patients who underwent OAGB or RYGB as primary or secondary procedures between 2010 and 2011 at a referral center were collected prospectively and analyzed retrospectively.

RESULTS

A total of 940 patients underwent OAGB (n = 405) or RYGB (n = 535). Operative time was significantly shorter in the OAGB group. Postoperative morbidity occurred in 17.2% of patients after RYGB versus 8.1% after OAGB (P ≤ .0001). Patients in the RYGB group had a significantly higher rate of kinking of the jejuno-jejunal anastomosis, stenosis of the gastrojejunal anastomosis, and dysphagia for early ulcers. At long term, no differences were found in the rate of severe malnutrition. Cumulated morbidity was significantly higher after RYGB, with higher incidence of internal hernia, anastomotic ulcer, blind-loop syndrome, and hypoglycemia. Conversion to RYGB and laparoscopic exploration for chronic pain were more frequent after OAGB. Surgery for weight regain was significantly more frequent after RYGB. Patients in the OAGB group had significantly lower weight, body mass index, and greater percentage excess, and total weight losses at 120 months. No significant differences were detected in co-morbidity outcomes.

CONCLUSION

After 10 years, both RYGB and OAGB are effective procedures. However, OAGB is associated with shorter operative times and better results in short- and long-term morbidity and weight loss outcomes.

150-cm Versus 200-cm Biliopancreatic Limb One-Anastomosis Gastric Bypass: Propensity Score-Matched Analysis

BACKGROUND

It has been suggested that shortening the length of the biliopancreatic limb (BPL) to 150 cm in one anastomosis gastric bypass (OAGB) would reduce nutritional complication rates without impairing weight loss outcomes. The aim of this study is to compare patients who underwent OAGB with a 200-cm BPL (OAGB-200) to patients with OAGB with a 150-cm BPL (OAGB-150) in terms of weight loss and late morbidity.

METHODS

This is a monocentric retrospective matched cohort study including patients with a body mass index between 35 and 50 kg/m² who underwent an OAGB-150 or an OAGB-200. Patients were matched 1:1 based on age, sex, and body mass index, prior to bariatric surgery.

RESULTS

In total, 784 patients who underwent OAGB were included (OAGB-150 n = 392 and OAGB-200 (n = 392). There was no significant difference in terms of early morbidity. Regarding late morbidity in patients with an OAGB-150, significantly lower rates for marginal ulcer (OR = 0.4, CI 95% [0.2; 0.8], p = 0.006), incisional hernia (OR = 0.5, CI 95% [0.3; 1], p = 0.041), and bowel obstruction (OR = 0.3, CI 95% [0.1; 0.9], p = 0.039) were reported. Likewise, regarding late nutritional deficiencies, post-OAGB-150, a significantly lower number of patients with hypoalbuminemia (OR = 0.3, CI 95% [0.2; 0.7], p = 0.006), low vitamin B9 (OR = 0.5, CI 95% [0.2; 1], p = 0.044), and low ferritin (OR = 0.5, CI 95% [0.3; 0.8], p = 0.005) were observed. There was no significant difference in the percentage of excess BMI loss at 1, 2, 3, 4, and 5 years.

CONCLUSION

Compared to OAGB-200 in patients with BMI ≤ 50 kg/m², OAGB-150 results in fewer nutritional deficiency rates long term, without impairing weight loss.

What Is the Efficacy of Short Length of Biliopancreatic Limb in One-Anastomosis Gastric Bypass? A Systematic Review and Meta-analysis of Short-Term Results

OBJECTIVE

To systematically review the efficacy of short length of biliopancreatic limb (BPL) in laparoscopic one anastomosis gastric bypass (OAGB).

METHODS

By thoroughly investigating in PubMed, Embase, and the Cochrane Library, each research containing the comparison between short BPL and 200-cm BPL was included, inception in July 2021. The research followed the guidance of Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) recommendations.

RESULT

A total of 1288 patients were included for meta-analysis. Results showed that in the short term, compared with 200-cm BPL, percentage excess weight loss (%EWL) did not show significant reduction (p = 0.91), neither did the incidence of vitamin D deficiency (p = 0.87) nor hypoalbuminemia (p = 0.06), while percentage total weight loss (%TWL) was significantly higher in the 200-cm BPL group (p = 0.0005). At 1, 2, and 8 years postoperatively, patients with short BPL still obtained significantly reduced body mass index (BMI).

CONCLUSION

Short BPL shows significant effect of weight loss; however, it seems no significantly lower rates of adverse events in the short term are found. More research with randomized controlled design is encouraged to further address the incidence of adverse events in the long term.

One-Anastomosis Gastric Bypass Revision for Gastroesophageal Reflux Disease: Long Versus Short Biliopancreatic Limb Roux-en-Y Gastric Bypass

PURPOSE

One-anastomosis gastric bypass (OAGB) may be associated with refractory gastroesophageal reflux disease (GERD). The nature of this GERD remains unclear. This complication can be treated either with an additional enteroenterostomy without shortening of gastric pouch (long biliopancreatic limb Roux-en-Y gastric bypass (L-BPL-RYGB)) or revision to conventional short biliopancreatic limb Roux-en-Y gastric bypass (S-BPL-RYGB). The objective of this study is to compare the aforementioned procedures in terms of efficacy on GERD symptoms.

MATERIALS AND METHODS

Retrospective analysis between October 2012 and June 2020.

RESULTS

Fifty-two patients underwent OAGB revision to S-BPL-RYGB (n = 21) or L-BPL-RYGB (n = 31) secondary to GERD. Investigation with pH impedance prior to revision was performed in 15 patients showing biliary reflux (BR) in 7 (46.6%), acid reflux (AR) in 6 (40%), and no confirmation in 2. Patients with AR had a revision to S-BPL-RYGB, whereas patients with BR underwent L-BPL-RYGB. Among the patients without pH metry results (n = 37), S-BPL-RYGB was performed for associated disabling digestive disorders or nutritional deficiencies. GERD was treated in 68% of patients with L-BPL-RYGB versus 95% of patients after S-BPL-RYGB. Patients, whose decision for revisional procedure was based on the results of pH impedance testing, did not reveal refractory GERD.

CONCLUSION

L-BPL-RYGB seems appropriate in patients with BR, whereas conversion to S-BPL-RYGB should be preferred if AR is present.

Outcome of Sleeve Gastrectomy Converted to Roux-en-Y Gastric Bypass and One-Anastomosis Gastric Bypass

Purpose

Sleeve gastrectomy (SG) is the commonest bariatric procedure worldwide but there is also a high conversion rate mainly due to weight regain and gastroesophageal reflux disease (GERD) reported in studies with long-term follow-up. The aim of this study is to highlight benefits and limitations of converting SG patients to Roux-en-Y gastric bypass (RYGB) and one-anastomosis gastric bypass (OAGB).

Setting

Retrospective cross-sectional-study, medical university clinic setting.

Methods

This study includes all patients converted from primary SG to RYGB or OAGB by 12/2018 at the Medical University of Vienna. Patients were examined using gastroscopy, esophageal manometry, 24-h pH-metry, and questionnaires.

Results

Fifty-eight patients were converted from SG to RYGB (n = 45) or OAGB (n = 13). Total weight loss of patients converted to RYGB and OAGB was 41.5% and 44.8%, respectively, at nadir. Six patients had Barrett’s esophagus (BE) after SG. In four out of these six patients, a complete remission of BE after conversion to RYGB was observed; nevertheless, two patients after RYGB and one after OABG newly developed BE. Clinical GERD improved at a higher rate after RYGB than after OAGB. Both revisional procedures improved associated medical problems.

Conclusion

Conversion to RYGB is probably the best option for patients with GERD after SG. OAGB has shown a low potential to cure patients from GERD symptoms after SG. In terms of additional weight loss and remission of associated medical problems, both procedures studied were equal. Surveillance gastroscopies every 5 years after SG revisions are recommended.

Graphical abstract

One-Anastomosis and Roux-en-Y Gastric Bypass Promote Similar Weight Loss, Patient Satisfaction, Quality of Life, Inflammation Grade, and Cellular Damage in the Esophagus and Gastric Pouch in a Short-term Follow-up

Background

One-anastomosis gastric bypass (OAGB) is a simpler procedure than Roux-en-Y gastric bypass (RYGB); however, biliary reflux can occur and impair outcomes. This study aimed to compare outcomes of OAGB and RYGB.

Methods

Twenty patients with morbid obesity were randomized prospectively into two groups: OAGB (n=10) or RYGB (n=10). Quality of life (36-item short-form health survey [SF-36]), satisfaction (Visick scale), and body mass index (BMI) were evaluated before and 6 months after the operation. All patients underwent esophagogastroduodenoscopy with gastric and esophageal mucosal biopsies at 3 and 6 months after their operation.

Results

The study found no significant difference in BMI before surgery (OAGB, 43.2 kg/m²; RYGB, 43.1 kg/m²; P=0.90) or at 6 months postoperative (OAGB, 32.1 kg/m²; RYGB, 31.8 kg/m²; P=0.91). There was no significant difference in improvement of quality of life (four SF-36 domains) or satisfaction (P=0.08) between groups at 6 months. There was no statistical difference between gastric (P=0.10) and esophageal (P=0.76) inflammation grade at three or 6 months between the two groups.

Conclusion

OAGB and RYGB are equally effective in terms of weight loss, patient satisfaction, and quality of life improvement at 6 months after the procedures. Inflammation grade and cellular damage in the gastric pouch and in the esophagus were similar.

Early and intermediate term outcomes after laparoscopic one-anastomosis gastric bypass for morbidly obese patients: a single center experience

Objectives

To evaluate our outcomes of laparoscopic one-anastomosis gastric bypass (LOAGB) as a primary weight loss procedure. We evaluated the impact of biliary reflux by combination of upper endoscopy (UGIE), ambulatory pH metry, and ambulatory biliary reflux monitoring.

Material and Methods

We reviewed the data of patients who underwent LOAGB during the period between July 2015 till August 2018.

Results

Forty consecutive patients were included in the study. Thirty-seven patients (92.5%) had obesity related comorbidities. The median follow-up duration was 18 months (6-36 months). The 1-, 2-, and 3-years excess weight loss percentages were 53.1%, 60.4%, and 62.3%. At three years follow-up, complete remission of diabetes mellitus occurred in 7/7 patients (100%) and of hypertension in 4/7 patients (57.1%). Eighteen patients (45%) accepted to undergo UGIE with routine biopsies and evaluation of acidic and biliary reflux. All examined patients had negative acid reflux results according to ambulatory PH metry with median DeMeester score of 2 (0.3-8.7). According to ambulatory biliary reflux monitoring, 17/18 patients (94.1%) had posi- tive result. Only 6/18 patients (33.3%) had symptoms of biliary reflux and had positive symptom index on bilimetric study. Regarding UGIE, all patients had just gastritis and reflux esophagitis with no evidence of gross mucosal changes. Pathological examination of all routine biopsies did not show any sign of faveolar hyperplasia, atypia or malignancy.

Conclusion

LOAGB is a safe and efficient bariatric procedure with acceptable morbidity rate. LOAGB is not associated with significant biliary reflux or pathological changes in the esophagogastric mucosa.

One-Anastomosis Gastric Bypass: Tehran Obesity Treatment Study (TOTS)

PURPOSE

This study aimed to evaluate body composition changes and the determinants of fat-free mass loss (FFML) up to 3 years after sleeve gastrectomy (SG) and one-anastomosis gastric bypass (OAGB).

MATERIALS AND METHODS

A prospective study was conducted on 3864 patients with severe obesity who underwent either SG (2746, 76.1% women, mean age: 39.2 ± 11.6 years, and BMI: 44.3 ± 5.6 kg/m²) or OAGB (1118, 82.2% women, age: 39.9 ± 10.7 years, BMI: 45.6 ± 6.3 kg/m²). Body composition parameters were measured by bioelectrical impedance analysis preoperatively and 1, 3, 6, 9, 12, 18, 24, and 36 months after surgery. Changes in body composition were assessed using the propensity matched generalized estimated equation (GEE) method. The determinants of fat-free mass loss/weight loss (FFML/WL%) were defined using a mixed-model GEE analysis.

RESULTS

Means of FM, FFM, and FFML/WL% decreased significantly in both study groups (P_trend < 0.001). Changes in BMI, EWL%, FM, and FFML/WL% were different between the two groups (P_between < 0.05). The results showed a better FFM preservation and a greater FM loss over time in the OAGB group compared to the SG group (P_interaction < 0.05). FFML during the first 3 months was greater in the SG compared to the OAGB group (P < 0.001). SG surgery, higher preoperative BMI, and female gender were associated with greater FFML/WL%.

CONCLUSION

In the SG compared to the OAGB group, FFML was greater, especially early after the surgery, emphasizing the need for therapeutic interventions such as regular exercise programs and dietary intake modifications.

The Effects of One-Anastomosis Gastric Bypass on Fatty Acids in the Serum of Patients with Morbid Obesity

Purpose

Obesity is associated with alterations in serum fatty acid profiles. One-anastomosis gastric bypass is a type of bariatric surgery used in the treatment of morbid obesity. The aim of this study was to establish if, between 6 and 9 months after this procedure, the fatty acid composition in the serum of patients normalizes to values similar to the healthy, lean population.

Materials/Methods

The study included 46 patients that underwent surgical treatment for obesity with one-anastomosis gastric bypass. The serum fatty acid composition was determined using gas chromatography-mass spectrometry. Principal component analysis was conducted to detect the differences between fatty acid profiles in patients pre- and post-surgery, and in 29 control nonobese subjects.

Results

Patients with morbid obesity were characterized by lowered levels of beneficial odd- and branched-chain fatty acids and polyunsaturated fatty acids. While the odd- and branched-chain fatty acid amounts normalized 6–9 months after bariatric treatment, the polyunsaturated fatty acid levels did not. Moreover, the total fatty acid profiles of patients pre- and post-bariatric surgery were still markedly different than those of lean, healthy controls.

Conclusion

Following one-anastomosis gastric bypass, there are some beneficial changes in serum fatty acids in treated patients, possibly due to weight loss and dietary regimen changes. However, they may be insufficient to restore the proper levels of other fatty acids, which may need to be additionally supplemented.

Graphical abstract

Acid Reflux Is Common in Patients With Gastroesophageal Reflux Disease After One-Anastomosis Gastric Bypass

INTRODUCTION

Patients with one-anastomosis gastric bypass (OAGB) can develop gastroesophageal reflux disease (GERD). The nature of this GERD (acid or biliary) remains unclear.

OBJECTIVE

To assess the nature of GERD via impedance pH testing in patients presenting with reflux post OAGB.

METHODS

Retrospective analysis of a prospectively collected database of 43 patients with OAGB backgrounds who developed postoperative GERD and were investigated with impedance pH monitoring between 2006 and 2019.

RESULTS

Mean age was 52.48 ± 9 years. Mean body mass index (BMI) prior to OAGB was 46.82 kg/m². None of these patients had clinical GERD before surgery. The median time interval between surgery and investigation with 24-h impedance pH monitoring was 64 (56) months. The mean BMI at the time of investigations was 32.67 ± 6.9 kg/m². The type of reflux was acid in 13 (30.2%), non-acid (biliary) in 12 (27.9%), and mixed (acid and biliary) in 5 (11.6%) patients. However, it remained not confirmed in 13 (30.2%). Median DeMeester score was 48.95 (27.67) in patients with acid, 2.8 (7.4) in patients with biliary, and 28.7 (5.6) in patients with mixed reflux. Median percent of time spent with pH < 4 was 9.65 (8) in patients with acid, 0.6 (1.75) in patients with biliary, and 7.7 (3.9) in patients with mixed reflux.

CONCLUSION

Acid reflux seems to be as common as bile reflux in patients presenting with GERD after OAGB. In case of revisional surgery for severe GERD post OAGB, 24-h impedance pH monitoring could be essential to determine the surgical procedure of choice.

Reversal to normal anatomy after one-anastomosis/mini gastric bypass, indications and results: a systematic review and meta-analysis

This review evaluates the indications and outcomes of one-anastomosis/mini gastric bypass (OAGB/MGB) reversal to normal anatomy. A systematic literature search and meta-analysis was performed in PubMed, Web of Science, and Scopus for articles published by October 1, 2020, including the keywords "one anastomosis gastric bypass," "OAGB," "mini gastric bypass," "MGB," "reversal," "reverse," "malnutrition," and "reversal bariatric surgery". After examining 182 papers involving 11,578 patients, 14 studies were included. A reversal was performed in 119 patients on average 23.6 months after the primary OAGB/MGB surgery. The mean body mass index (BMI) was 22.92 ± 3.47 kg/m² and the mean albumin level was 25.17 ± 4.21 g/L at reversal. The mean length of the common channel (CC) was 383.57 ± 159.35 cm, with a mean biliopancreatic limb (BPL) length of 214.21 ± 48.45 cm. Pooled estimation of the meta-analysis of prevalence studies reported a prevalence of 1% for reversal. The major signs and symptoms of protein-energy malnutrition were the leading causes of the reversal of OAGB/MGB. Bleeding, leakage, and death due to severe liver failure were the most reported complications after reversal, with an overall incidence of 10.9%. In conclusion, OAGB/MGB reversal has a prevalence of 1% and has a complication rate of 10.9%. Protein-energy malnutrition with hypoalbuminemia was the most common etiology. The mean lengths of BPL and CC were reported as 215 cm and 380 cm, respectively, in the cases. Therefore, special attention should be paid to malnutrition in all OAGB/MGB patients during follow-up to prevent severe malnutrition and subsequent increase in reversal procedures.

Utility of Inflammatory Markers in Detection of Perioperative Morbidity After Laparoscopic Sleeve Gastrectomy, Laparoscopic Roux-en-Y Gastric Bypass, and One-Anastomosis Gastric Bypass-Multicenter Study

Background

The most commonly performed bariatric operations are laparoscopic sleeve gastrectomy (LSG) and bypass surgeries (laparoscopic one-anastomosis gastric bypass (OAGB) and laparoscopic Roux-en-Y gastric bypass (LRYGB)), and predicting perioperative morbidity is crucial for early, safe patient discharge. We aimed to determine whether C-reactive protein (CRP) and white blood count (WBC) measured on the first postoperative day predicts perioperative morbidity in the first 30-days after LSG and bypass surgeries.

Methods

We retrospectively analyzed data for 1400 patients who underwent bariatric surgery in seven bariatric centers from 2014 to 2018. Patients were divided into a complicated group (patients with postoperative complications) and a non-complicated group. We also performed separate analyses for LSG and bypass surgeries.

Results

Patients were 929 women (66%) and 471 men (34%) with a median age of 42 years (range, 35–51 years); 1192 patients underwent LSG (85%), 120 underwent LRYGB (9%), and 80 underwent OAGB (6%). We performed ROC analyses to set cut-off points, followed by multivariate logistic regressions. CRP > 33.32 mg/L increased the odds ratio (OR) of perioperative complications after LSG 2.27 times, while WBC > 12.15 × 10³/μL on postoperative day 1 was associated with a 3.34-times greater or of developing complications. WBC > 13.78 × 10³/μL was associated with a 13.34-times higher or of perioperative morbidity in patients undergoing bypass surgeries.

Conclusion

Even slightly elevated CRP and WBC on postoperative day 1 should alert surgeons to the potential risk of perioperative morbidity.

IFSO (International Federation for Surgery of Obesity and Metabolic Disorders) Consensus Conference Statement on One-Anastomosis Gastric Bypass (OAGB-MGB): Results of a Modified Delphi Study

BACKGROUND

One-anastomosis gastric bypass (OAGB-MGB) is currently the third performed primary bariatric surgical procedure worldwide. However, the procedure is hampered by numerous controversies and there is considerable variability in surgical technique, patient selection, and pre- and postoperative care among the surgeons performing this procedure. This paper reports the results of a modified Delphi consensus study organized by the International Federation for Surgery of Obesity and Metabolic Disorders (IFSO).

METHODS

Fifty-two internationally recognized bariatric experts from 28 countries convened for voting on 90 consensus statements over two rounds to identify those on which consensus could be reached. Inter-voter agreement of ≥ 70% was considered consensus, with voting participation ≥ 80% considered a robust vote.

RESULTS

At least 70% consensus was achieved for 65 of the 90 questions (72.2% of the items), 61 during the first round of voting and an additional four in the second round. Where consensus was reached on a binary agree/disagree or yes/no item, there was agreement with the statement presented in 53 of 56 instances (94.6%). Where consensus was reached on a statement where options favorable versus unfavorable to OAGB-MGB were provided, including statements in which OAGB-MGB was compared to another procedure, the response option favorable to OAGB-MGB was selected in 13 of 23 instances (56.5%).

CONCLUSION

Although there is general agreement that the OAGB-MGB is an effective and usually safe option for the management of patients with obesity or severe obesity, numerous areas of non-consensus remain in its use. Further empirical data are needed.

Short-Term Changes on Body Composition and Bone Mass After One-Anastomosis Gastric Bypass: a Prospective Observational Study

PURPOSE

Bariatric surgery generates a large weight loss. It is considered a successful surgery when 50% of the excess weight loss is reached. However, this measure does not include some variables that may have a direct impact on a patient's health, such as fat-free mass (FFM) or bone mass. Therefore, the aim of this study is to evaluate body composition and bone mass in patients undergoing one-anastomosis gastric bypass (OAGB).

METHODS

A prospective observational study was performed in patients undergoing OAGB. Body composition and bone mass were evaluated by bioelectrical impedance analysis at baseline (1 day prior to surgery), at 6 and 12 months after surgery.

RESULTS

A total of 94 patients (67% females and 33% males) were included in the study. The excess BMI loss at 6 and 12 months after surgery was 97.9 ± 20.1% and 110.2 ± 30.5% respectively. The FFM showed a reduction of 6.6 ± 4.8 kg (p < 0.01) 6 months after surgery and of 7.9 ± 4.9 kg (p < 0.01) at 12 months, meaning a decrease of 10.5 ± 7.3% and a 12.9 ± 6.6% respectively. The bone mass decrease was 10.1 ± 6.9% (p < 0.01) and 12.9 ± 6.5% (p < 0.01) at 12 months after OAGB.

CONCLUSIONS

OAGB obtains a relevant weight loss in patients with morbid obesity, mainly, due to fat mass reductions. However, this procedure also provokes FFM and bone mass decreases, especially in females, but not significantly greater than other restrictive or mixed procedures.

Missing Jejunal Perforation During Small Bowel Measurement in Patient Operated by Laparoscopic One-Anastomosis Gastric Bypass

BACKGROUND

Obesity surgery is justified as it produces sustained weight loss, increases life expectancy, and reduces the complications of obesity. For this reason, increasing numbers of patients are undergoing this surgery [1]. Complications following surgical treatment of severe obesity vary based upon the procedure performed and, although it is currently below 7% in more experienced centers, it may increase in more complex surgeries (such as revision surgery) and can be as high as 40% [2, 3]. Patients with early postoperative complications may be managed in specialist centers by the bariatric surgeon during the hospital stay [4]. Missing bowel injury may occur primarily during insertion of a Veress needle and trocar, use of electrosurgery and laser beams, suturing, and adhesiolysis [5]. Less frequently, the bowel perforation is due to the measurement of the loop and goes unnoticed. Perforation of the intestines due to any reason is a severe condition that can clinically present with free intraabdominal air, purulent or even fecal peritonitis, and abdominal compartment syndrome [6]. High clinical suspicion is crucial for early diagnosis. Early recognition of bowel injury and early intervention is crucial to reduce its morbidity and mortality [5].

METHODS

We present a case of a 50-year-old male patient with a BMI of 36.1 kg/m², hypertension, and dyslipidemia who was proposed for bariatric surgery. A laparoscopic one-anastomosis gastric bypass (OAGB) was performed with no intraoperative incidents. Few hours after the surgery, the patient manifests intense abdominal pain and tachycardia (120 bpm) so we decided to order an abdominal CT scan that showed signs of jejunal perforation (pneumoperitoneum, oral contrast extravasation, and small air bubbles next to the jejunum wall).

RESULTS

Emergency laparoscopy was done and showed generalized peritonitis caused by a 4-mm perforation in the mesenteric border of the jejunum with everted mucosa that was located 150 cm from the loop of Treitz. We decided to place three infraumbilical trocars to help us with washing, viewing, and surgical repair. We performed a 2-0 barbed simple suture of the perforation and extensive washing of the entire cavity with 10 L of serum. We left three drains. The patient made an uneventful recovery and was discharged 72 h after surgery with an established oral diet.

CONCLUSIONS

Missing intestinal perforation is an uncommon injury during bariatric surgery, but its early diagnosis is important to avoid endangering the patient's life. Simple postoperative tachycardia in obese patients should be taken seriously as it is a warning signal. Laparoscopic reoperation in these early diagnosed cases is safe and effective, since it allows visualization and washing of the entire cavity. Bowel injuries, which may occur as a result of the insertion of an insufflation needle or trocar, are a rare complication of laparoscopy. In the case we present, the perforation occurred during the small bowel measurement so we insist on the extreme caution that surgeons must take during every detail of the surgical technique. The use of atraumatic forceps, handling of the bowel strictly at the antimesenteric side, and the infusion of sufficient methylene blue in the anastomosis testing are gestures that can help reduce the risk.

Internal Hernia After Laparoscopic One-Anastomosis (Mini) Gastric Bypass: Video Case Series of a Single-Center Experience

Internal hernia (IH) after one-anastomosis gastric bypass (OAGB) was thought to have an extremely low incidence. In this video, we report three cases of post-OAGB symptomatic internal herniation. The first case is a 45-year-old female who presented 4 months after her OAGB with crampy abdominal pain and reflux symptoms. An exploratory laparoscopy showed Petersen's hernia; the hernia was reduced with no ischemia and the defect was closed. The second case is a 40-year-old male who presented 7 months after his surgery with abdominal pain and reflux. An exploratory laparoscopy showed Petersen's hernia; bowel was reduced and defect was closed through a laparotomy. The third case is a 64-year-old male who presented with refractory biliary reflux after OAGB. An elective diagnostic laparoscopy showed Petersen's hernia; the hernia was reduced and defect was closed. All patients recovered well with no recurrence of symptoms on follow-up. Internal hernia after OAGB is more common than the reported incidence. The threshold for diagnostic laparoscopy should be lowered for a OAGB patient with symptoms suggestive of IH.

Bridged one-anastomosis gastric bypass: technique and preliminary results

PURPOSE

One-anastomosis gastric bypass (OAGB) is an established bariatric procedure performed worldwide. We developed a modification of OAGB leaving a bridge at the cranial 2 cm of the fundus as a gastro-gastric fistula to allow for endoscopic access to the bypassed stomach. We present the preliminary results of 44 patients who underwent this technique in our hospital.

METHODS

We analyzed, retrospectively, data collected prospectively on 44 patients who underwent our bridged one-anastomosis gastric bypass (BOAGB) procedure between September, 2018 and November, 2020.

RESULTS

The mean age of the patients was 45.2 ± 9.3 years (range 20-66 years). The mean preoperative body mass index (BMI), weight, and HbA1c values were 41.5 ± 6.4 kg/m² (range 35-59), 116 ± 22.7 kg, and 8.2 ± 2.1%, respectively. After a median follow-up period of 18 months (11-26 months), the mean postoperative BMI was 28.4 ± 3.2 kg/m² (range 21-38), the mean total weight loss was 35.8 ± 13.5 kg (range 20-80 kg), and the mean percentage of excess weight loss (%EWL) and the percentage of total weight loss (%TWL) were 79.8 ± 16.1% (range 47-109) and 30.6 ± 6.9% (range 19-48), respectively. The mean postoperative HbA1c level was 6.3 ± 0.9%. There were two early complications (stenosis and bleeding) and one late complication (marginal ulcer).

CONCLUSION

Patients who underwent BOAGB lost weight similarly to those who underwent OABG as reported in the literature, without an apparent increase in complications related to the technique. Randomized studies with longer term follow-up are needed.

Impact of COVID-19 Lockdown on Short-term Weight Loss in a Single Italian Institution

Italy was the first European country to have a major outbreak of COVID-19. Bariatric procedures were stopped and telemedicine had to be implemented. A large percentage of patients struggled to follow postoperative diet and to start physical activity due to social restrictions. We have compared short-term outcomes of patients who had bariatric procedures prior to lockdown with subjects that had undergone obesity surgery in the same period of the previous year at our institution. A total number of 63 patients were included in this study. Weight loss at 1, 3 and 6 postoperative months in the 2019 group was significantly higher at any point of follow-up when compared to 2020. Social limitations and nonattendance of clinical appointments may have compromised early results.

Bariatric surgery in Mexico: training, practice and surgical trends

Bariatric surgery is extremely safe and effective, but several factors need to be addressed to obtain such results. Patient selection, type of training, accreditation, type of practice, and surgical trends and technique are involved in this process. Local and global standardization are ill-advised, especially in countries with high obesity prevalence, and where the bariatric practice is fast growing.An online survey with 22 questions was sent to bariatric surgeons in Mexico. Only participants with the active practice were included, and the aim was to obtain for the first time insight in bariatric surgery training, characteristics of current practice and surgical trends.Complete responses from 114 surgeons were obtained. Most were male, under 50 years-old, ≤ 10 years of experience, and practice in low-volume hospitals. Less than half had a 12-month formal training. Gastric bypass and sleeve gastrectomy were the most common procedures. Practice trends like leak tests, use of drains, preoperative weight loss, routine endoscopy, and pharmacological tromboprofilaxis are common. In surgical technique, the gastric bypass and sleeve gastrectomy confection was more homogenic when compared to the one-anastomosis gastric bypass.Complete responses from 114 surgeons were obtained. Most were male, under 50 years-old, ≤ 10 years of experience, and practice in low-volume hospitals. Less than half had a 12-month formal training. Gastric bypass and sleeve gastrectomy were the most common procedures. Practice trends like leak tests, use of drains, preoperative weight loss, routine endoscopy, and pharmacological tromboprofilaxis are common. In surgical technique, the gastric bypass and sleeve gastrectomy confection was more homogenic when compared to the one-anastomosis gastric bypass. An important number of bariatric surgeons in Mexico are young, male, and with < 10 years of practice. The most common techniques performed are gastric bypass and sleeve gastrectomy. Several practices and technique trends are similar to global consensus. Fellowship programs and Board Certification in bariatric surgery are major advances in our country, thus standardization and high-quality practice can be achieved.

Postoperative Outcomes and Advantages of Hand-Sewn Laparoscopic One-Anastomosis Gastric Bypass: Experience on 805 Patients

PURPOSE

One-anastomosis gastric bypass (OAGB) is a novel laparoscopic approach. The anastomosis of OAGB can be sewn either with a stapler or manually. The aim of this study is to determine the outcome of hand-sewn OAGB.

MATERIALS AND METHODS

A total of 805 consecutive patients were retrospectively enrolled in this study. Data collection included change in weight, body mass index (BMI), symptoms, and complications before surgery and continued during annual follow-up visits up to 5 years. Inclusion criteria were patients with a BMI of higher than 40 kg/m2 or higher than 35 kg/m2 with one severe comorbidity. Patients with BMI > 50 kg/m2 were referred to dieticians.

RESULTS

The follow-up rate ranged from 93 to 50% at the 1-year and 5-year visits after surgery, respectively. Mean weight and BMI of patients before surgery were 121.93 kg (± 22.92) and 44.79 kg/m2 (± 6.07), respectively. Mean of annual BMI in 5 years of follow-up were 27.83, 27.26, 28.90, 29.45, and 29.56 kg/m2. Excess weight loss (EWL) in 5 years of follow-up were 85.7%, 89.5%, 78.9%, 77.7%, and 76.0%. Reflux was present in 202 patients (25.1%) before surgery and resolved in 153 cases (75.7%) 1 year after surgery. Procedure-specific early complication was an anastomosis leak in one patient, which led to death. Two cases of malnutrition necessitating reversal and two severe reflux disorders leading to Roux-en-Y bypass surgery were remarkable late complications.

CONCLUSION

Hand-sewn anastomosis could represent an efficient and safe technique in the management of patients undergoing OAGB surgery with acceptable outcomes and rare adverse complications.

Sleeve Gastrectomy, One-Anastomosis Gastric Bypass (OAGB), and Single Anastomosis Sleeve Ileal (SASI) Bypass in Treatment of Morbid Obesity: a Retrospective Cohort Study

PURPOSE

Bariatric surgery is the most effective treatment for morbid obesity. The present study aimed to assess three bariatric procedures with different mechanisms of actions; sleeve gastrectomy (SG), one-anastomosis gastric bypass (OAGB), and single anastomosis sleeve ileal (SASI) bypass, in terms of efficacy and safety.

METHODS

This was a retrospective cohort study on patients with morbid obesity who underwent SG, OAGB, or SASI bypass. The main outcome measures were weight loss and improvement in comorbidities at 6 and 12 months postoperatively, and complications.

RESULTS

A total of 264 patients (186 female) with mean preoperative body mass index (BMI) of 43.6 ± 9.9 kg/m²were included to the study. Significant weight loss was recorded at 6 and 12 months after the three procedures. At 6 and 12 months postoperatively, body weight and BMI were significantly lower after SASI bypass than after SG and OAGB. The %total weight loss (%TWL) and %excess weight loss (%EWL) were significantly higher after SASI bypass than after SG and OAGB. SASI bypass was associated with a significantly higher rate of improvement in DM than SG and OAGB (97.7% vs 71.4% vs 86.7%; p = 0.04) whereas improvement in other comorbidities was similar. The short-term complication rate was similar between the three procedures, yet SASI bypass was followed by higher long-term complication rate.

CONCLUSION

Based on retrospective review of data, SASI bypass was associated with more reduction in body weight and BMI, higher %TWL and %EWL, better improvement in T2DM, and more long-term nutritional complications than SG and OAGB.

Effect of one-anastomosis gastric bypass on cardiovascular risk factors in patients with vitamin D deficiency and morbid obesity: A secondary analysis

BACKGROUND AND AIMS

Bariatric patients often suffer from vitamin D (VD) deficiency, and both, morbid obesity and VD deficiency, are related to an adverse effect on cardiovascular disease (CVD) risk. Therefore, we assessed the change of known CVD risk factors and its associations during the first 12 months following one-anastomosis gastric bypass (OAGB).

METHODS AND RESULTS

In this secondary analysis, CVD risk factors, medical history and anthropometric data were assessed in fifty VD deficient (25-hydroxy-vitamin D (25(OH)D) <75 nmol/l) patients, recruited for a randomized controlled trial of VD supplementation. Based on previous results regarding bone-mass loss and the association between VD and CVD risk, the study population was divided into patients with 25(OH)D ≥50 nmol/l (adequate VD group; AVD) and into those <50 nmol/l (inadequate VD group; IVD) at 6 and 12 months (T6/12) postoperatively. In the whole cohort, substantial remission rates for hypertension (38%), diabetes (30%), and dyslipidaemia (41%) and a significant reduction in CVD risk factors were observed at T12. Changes of insulin resistance markers were associated with changes of total body fat mass (TBF%), 25(OH)D, and ferritin. Moreover, significant differences in insulin resistance markers between AVD and IVD became evident at T12.

CONCLUSION

These findings show that OAGB leads to a significant reduction in CVD risk factors and amelioration of insulin resistance markers, which might be connected to reduced TBF%, change in 25(OH)D and ferritin levels, as an indicator for subclinical inflammation, and an adequate VD status. REGISTERED AT CLINICALTRIALS.GOV: (Identifier: NCT02092376) and EudraCT (Identifier: 2013-003546-16).