The importance of the length of the limbs for gastric bypass patients--an evidence-based review

Long-term Outcome of the Dutch Common Channel Trial (DUCATI): Preservation of Superior Weight Loss Results Without Significant Malnutrition Side Effects

PURPOSE

The optimal bowel limb lengths for laparoscopic Roux-en-Y gastric bypass (LRYGB) to maximize weight loss while minimizing nutritional deficiencies in severe obesity treatment remain a topic of debate. The multi-center Dutch Common Channel Trial (DUCATI) aims to compare the outcomes of a very long Roux Limb Roux-en-Y gastric bypass (VLRL-LRYGB) with a standard Roux-en-Y gastric bypass (S-LRYGB).

METHODS

A total of 444 patients were randomly assigned in a 1:1, double-blind manner to undergo either VLRL-RYGB or S-LRYGB. Five-year follow-up data were assessed, concentrating on weight loss, obesity-related medical conditions, complications, re-operations, and malnutrition.

RESULTS

Both groups had comparable total alimentary lengths (RL + CC). The VLRL-LRYGB group demonstrated significantly greater %TWL (32.2% vs. 28.6%, p = 0.002) and %EWL (81.2% vs. 70.3%, p = 0.002) at 5 years. Eight (3.6%) patients in the VLRL-LRYGB group versus 2 (0.9%) in the S-LRYGB group (p = 0.055) needed modification surgery for malabsorption. Suboptimal clinical response rate was significantly higher (22.0% vs. 8.3%) in S-LRYGB group. No significant differences for nutrient deficiencies in favor of the S-LRYGB group were found.

CONCLUSION

A 100-cm common channel with a relatively long Roux limb provides superior, sustainable weight loss over 5 years, without significantly increased rate of malabsorption-related re-operations. These results suggest that a longer Roux limb can still ensure adequate micronutrient uptake in the total alimentary tract. These findings should be considered in discussions regarding the optimal Roux-en-Y limb length for severe obesity treatment.

American society for metabolic and bariatric surgery: intra-operative care pathway for minimally invasive Roux-en-Y gastric bypass

BACKGROUND

Clinical care pathways help guide and provide structure to clinicians and providers to improve healthcare delivery and quality. The Quality Improvement and Patient Safety Committee (QIPS) of the American Society for Metabolic and Bariatric Surgery (ASMBS) has previously published care pathways for the performance of laparoscopic sleeve gastrectomy (LSG) and pre-operative care of patients undergoing Roux-en-Y gastric bypass (RYGB).

OBJECTIVE

This current RYGB care pathway was created to address intraoperative care, defined as care occurring on the day of surgery from the preoperative holding area, through the operating room, and into the postanesthesia care unit (PACU).

METHODS

PubMed queries were performed from January 2001 to December 2019 and reviewed according to Level of Evidence regarding specific key questions developed by the committee.

RESULTS

Evidence-based recommendations are made for care of patients undergoing RYGB including the pre-operative holding area, intra-operative management and performance of RYGB, and concurrent procedures.

CONCLUSIONS

This document may provide guidance based on recent evidence to bariatric surgeons and providers for the intra-operative care for minimally invasive RYGB.

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

INTRODUCTION

Different limb lengths are used in Roux-en-Y gastric bypass (RYGB) surgery, as there is no consensus which limb length strategy has the best outcomes. The biliopancreatic limb (BPL) is thought to play an important role in achieving weight loss and associated comorbidity resolution. The objective of this study was to assess the impact of a longer BPL on weight loss and comorbidity improvement at 5 years after primary RYGB.

METHODS

All patients aged ≥ 18 years undergoing primary RYGB between 2014-2017 with registered follow-up 5 years after surgery were included. Long BPL was defined as BPL ≥ 100 cm and short BPL as BPL < 100 cm. The primary outcome was achieving at least 25% total weight loss (TWL) at 5 years. Secondary outcomes included absolute %TWL and improvement of comorbidities. A propensity score matched logistic and linear regression was used to estimate the difference in outcomes between patients with long and short BPL.

RESULTS

At 5 years, long BPL had higher odds to achieve ≥ 25% TWL (odds ratio (OR) 1.19, 95% confidence interval (CI) [1.01 - 1.41]) and was associated with 1.26% higher absolute TWL (β = 1.26, 95% CI [0.53 - 1.99]). Furthermore, long BPL was more likely to result in improved diabetes mellitus (OR = 2.17, 95% CI [1.31 - 3.60]) and hypertension (OR = 1.45, 95% CI [1.06 - 1.99]).

CONCLUSION

Patients undergoing RYGB with longer BPL achieved higher weight loss and were more likely to achieve improvement of comorbidities at 5 years.

Gastrointestinal Permeability After Bariatric Surgery: A Systematic Review

Gastrointestinal permeability refers to the movement of substances across the gut wall. This is mediated by endotoxemia (bacterial products entering the systemic circulation), and is associated with metabolic disease. The effect of bariatric surgery on permeability remains uncertain; the associated dietary, metabolic and weight changes are suggested to influence, or trigger, altered permeability. The primary aim of this study is to synthesize evidence and analyze the effect of bariatric surgery on permeability. A systematic review was performed, searching MEDLINE, EMBASE, and Scopus until February 2023, using MESH terms "intestinal permeability", "bariatric", for studies reporting in vivo assessment of permeability. Three cohort studies and two case series were identified (n=96). Data was heterogeneous; methodology and controls preclude meta-analysis. Gastroduodenal permeability reduced post-sleeve gastrectomy (SG). Two studies showed an increase in small intestinal permeability after biliopancreatic diversion. Two studies revealed a decrease in post-Roux-en-Y gastric bypass. One study identified increased colonic permeability six months post-SG. Evidence regarding permeability change after bariatric surgery is conflicting, notably for the small intestine. Impaired colonic permeability post-SG raises concerns regarding colonic protein fermentation and harmful dietary sequelae. There are multiple interacting variables confounding gastrointestinal permeability change; procedure type, altered microbiota and metabolic response to surgery. Further understanding of this important aspect of obesity is required, both before and after bariatric surgery.

Long Biliopancreatic Limb Roux-En-Y Gastric Bypass Versus One-Anastomosis Gastric Bypass: a Randomized Controlled Study

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is the gold standard in bariatric surgery. The one-anastomosis gastric bypass (OAGB) procedure, first introduced by Dr. Rutledge, has demonstrated a 25% greater weight loss efficiency than the traditional Roux-en-Y gastric bypass (RYGB) procedure due to the substantially longer biliopancreatic limb (BPL).

AIM OF THE STUDY

The current work aimed to compare the outcomes of OAGB and long BPL RYGB regarding weight loss and comorbidity resolution.

PATIENTS AND METHODS

This randomized controlled trial was done at our institution between September 2019 and January 2021. Patients who were candidates for bariatric surgery were randomly and equally allocated to two groups. Group A underwent OAGB, while group B underwent long BPL RYGB. Patients were followed up for 6 months postoperatively.

RESULTS

This study included 62 patients equally allocated to OAGB or long BPL RYGB, with no dropouts during follow-up. At 6 months, there was no statistically significant difference between the two groups regarding postoperative BMI (P = 0.313) and the EBWL (P = 0.238). There was comparable remission of diabetes mellitus (P = 0.708), hypertension (P = 0.999), OSA (P = 0.999), joint pain (P = 0.999), and low back pain (P = 0.999). Seven patients in the OAGB group experienced reflux symptoms (P = 0.011), which were managed by proton pump inhibitors.

CONCLUSION

Extending the BPL in RYGB provides weight loss and comorbidity remission comparable to that of OAGB. Some OAGB-related reflux cases remain a concern. However, they were sufficiently controlled with PPIs. Due to OAGB superior technical simplicity, long BPL RYGB should be preserved for cases whom are more risky for bile reflux.

Optimal common limb length in Roux‐en‐Y gastric bypass surgery: is it important for an ideal outcome? – a systematic review

BACKGROUND

In Roux-en-Y gastric bypass (RYGB) surgery the common limb length (CLL) is thought to significantly impact on nutritional and metabolic outcomes. However, there has been little focus on establishing routine standardized CLL measurements and its subsequent effect on weight loss and nutritional status. This review aimed to determine the effect of variations of CLL in RYGB surgery on post-operative outcomes, particularly nutritional status, while considering the need for routine CLL measurements in addition to measuring biliopancreatic limb and alimentary limb lengths.

METHODS

A systematic review was performed in accordance with the PRISMA guidelines. All English language articles addressing CLL and impact on weight loss, nutritional and metabolic outcomes were retrieved and reviewed.

RESULTS

Thirteen relevant studies were identified with CLLs varying from 76 to >600 cm. No significant difference in total body weight loss or excess weight loss was observed. Significant metabolic improvements occurred with shorter CLLs. Nutritional deficiencies were more severe when the CLL was <400 cm.

CONCLUSION

The data from this systematic review suggests that reasonable weight loss and positive impacts on metabolic outcomes can be achieved with CLLs of >400 cm.

Length of biliopancreatic limb in Roux-en-Y gastric bypass and its impact on post-operative outcomes in metabolic and obesity surgery-systematic review and meta-analysis

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is a gold-standard procedure for treatment of obesity and associated comorbidities. No consensus on the optimal design of this operation has been achieved, with various lengths of bypassed small bowel limb lengths being used by bariatric surgeons. This aim of this systematic review and meta-analysis was to determine whether biliopancreatic limb (BPL) length in RYGB affects postoperative outcomes including superior reduction in weight, body mass index (BMI), and resolution of metabolic comorbidities associated with obesity.

METHODS

A systematic search of the literature was conducted up until 1st June 2021. Meta-analysis of primary outcomes was performed utilising a random-effects model. Statistical significance was determined by p value < 0.05.

RESULTS

Ten randomised controlled trials were included in the final quantitative analysis. No difference in outcomes following short versus long BLP in RYGB was identified at 12-72 months post-operatively, namely in BMI reduction, remission or improvement of type 2 diabetes mellitus, hypertension, dyslipidaemia, and complications (p > 0.05). Even though results of four studies showed superior total body weight loss in the long BPL cohorts at 24 months post-operatively (pooled mean difference -6.92, 95% CI -12.37, -1.48, p = 0.01), this outcome was not observed at any other timepoint.

CONCLUSION

Based on the outcomes of the present study, there is no definitive evidence to suggest that alteration of the BPL affects the quantity of weight loss or resolution of co-existent metabolic comorbidities associated with obesity.

The Effect of Vitamin D Supplementation on Serum 25-Hydroxy Vitamin D in the Patients Undergoing Bariatric Surgery: a Systematic Review and Meta-Analysis of Randomized Clinical Trials

Currently, there is no consensus on the optimal vitamin D administration in bariatric patients. The present systematic review and meta-analysis were conducted to examine the effect of vitamin D supplements on serum level of 25(OH) vitamin D in the patients undergoing bariatric surgery (BS).Random model effects were used to estimate standardized mean difference (SMD) with a 95% confidence interval (CI). Nine clinical trials were included in the meta-analysis. Vitamin D supplementation in patients undergoing BS modestly improves vitamin D status (SMD, 0.53; 95% CI, 0.28, 0.77) particularly, in the dosages above 2850 IU/day and in the patients with BMI greater than 50 kg/m². Vitamin D supplementation was associated with prevention of raising of the PTH serum concentration and without impact on serum calcium levels.

Variation of Laparoscopic Roux-en-Y Gastric Bypass Techniques: a Survey of 518 Bariatric Surgeons

INTRODUCTION

Surgical technique varies dramatically in the performance of laparoscopic Roux-en-Y gastric bypass (LRYGB) and these differences can potentially lead to variation in outcomes. The objective of this study was to characterize surgical techniques used during LRYGB.

METHODS

An anonymous 44-question survey was distributed by email to all bariatric surgeons with membership in the ASMBS, SAGES, and ACS from April to June 2020. Questions were designed to evaluate surgeon demographics, experience, and variation of techniques. Only surgeons who performed LRYGB within the past year were included for analysis.

RESULTS

A total of 534 (18.8%) surgeons responded and the majority (97.0%) reported performing LRYGB in the past year. Surgeons were predominantly from the USA (77.8%). For preoperative work-up, 20.1% performed upper gastrointestinal series while 60.8% performed esophagogastroduodenoscopy. Limb length evaluation revealed mean Roux and biliopancreatic limb lengths of 124.1 ± 29.4 cm and 67.4 ± 32.2 cm, respectively. The gastrojejunostomy was most commonly formed using a linear stapler with handsewn closure of the common enterotomy (53.1%) and the jejunojejunostomy using a linear stapled anastomotic technique with handsewn closure of the common enterotomy (60.6%). The majority of surgeons closed the jejunojejunostomy mesenteric defect (91.1%) and one of the antecolic or retrocolic mesenteric defects (65.1%). Intraoperative leak tests were performed in 95.9% of cases. Only 22.1% of surgeons routinely performed upper gastrointestinal swallow studies postoperatively.

CONCLUSIONS

There are wide variations in pre- and intraoperative practice patterns for LRYGB. Further clinical trials designed to evaluate the impact of these practice pattern differences on patient outcomes are warranted.

Standard Biliopancreatic Limb (50 cm) Roux-en-Y Gastric Bypass Versus Long Biliopancreatic Limb (100 cm) Roux-en-Y Gastric Bypass in Patients with Body Mass Index 40-50 kg/m2: a Randomized Prospective Study

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is a widely performed procedure worldwide especially with the presence of associated medical conditions. Patients with body mass index (BMI) 40-50 kg/m² are at more risk of weight regain and relapse of comorbidities. There is a controversy on the optimum alimentary (AL) and biliopancreatic (BPL) limb lengths to be used in RYGB to achieve weight loss and remission of comorbidities without causing nutritional deficiencies in those patients.

STUDY DESIGN

hundred-and-fifty patients with BMI between 40 and 50 kg/m² were divided equally into 2 groups undergoing standard RYGB (S-RYGB) with AL:150 cm and BPL: 50 cm and long biliopancreatic RYGB (L-RYGB) with AL: 100 cm and BPL: 100 cm. BMI, % of total weight loss (%TWL), effect on diabetes (DM), hypertension (HTN), dyslipidemia, and nutritional statuses were recorded at 1, 2, and 3 years.

RESULTS

Only 64/75 patients in S-RYGB and 57/75 patients in L-RYGB completed the study. L-RYGB had faster weight loss, higher %TWL, and less BMI than S-RYGB with the maintenance of achieved weight. L-RYGB had better control of DM and dyslipidemia than S-RYGB. There were no significant differences in nutritional status between S-RYGB and L-RYGB rather than lower levels of calcium and Hb and higher levels of PTH in L-RYGB yet they remain within the normal range.

CONCLUSION

The application of L-RYGB helps in achieving faster weight loss for a longer period with better remission of associated comorbidities as DM, HTN, and dyslipidemia in patients with BMI 40-50 kg/m² but with effects on the nutritional status.

One Anastomosis Gastric Bypass Versus Long Biliopancreatic Limb Roux-en-Y Gastric Bypass

Background

Roux-en-Y gastric bypass (RYGB) is one of the most effective bariatric procedures. The study aimed to explore the value of lengthening the biliopancreatic limb (BPL) in RYGB compared to the outcome of one-anastomosis gastric bypass (OAGB).

Methods

This prospective study included morbidly obese patients divided into two groups. The RYGB group (n = 36) was subjected to long biliary limb Roux-en-Y gastric bypass (LPRYGB), and the OAGB Group (n = 36) had one anastomosis gastric bypass. During follow-up, weight, BMI, percentage of excess body weight loss (%EBWL), resolution of obesity-related comorbidities, and quality of life (QoL) were evaluated.

Results

There was no significant difference in weight and BMI after 3 and 6 months. At 12-month follow-up, weight loss was significantly higher in the OAGB group. After 12 months, the two groups showed significant improvement of comorbid conditions without significant difference between the two groups. The Qol was significantly higher in the LPRYGB group 3, 6, and 12 months after surgery compared to the OAGB group.

Conclusions

Extending the BPL length in RYGB to 150 cm is as effective as OAGB in remission of comorbidities, including diabetes. It was also equally effective in weight reduction in the short term. OAGB was more efficient in weight reduction and a significantly faster operation. LPRYGB showed a better QoL of life 1 year after surgery.

Graphical abstract

Standard versus distal Roux-en-Y gastric bypass in patients with BMI 50-60 kg/m2: 5-year outcomes of a double-blind, randomized clinical trial

Background

The optimal surgical weight loss procedure for patients with a BMI of 50 kg/m² or more is uncertain. This study compared distal Roux-en-Y gastric bypass (RYGB) with standard RYGB.

Methods

In this double-blind RCT, patients aged 18–60 years with a BMI of 50–60 kg/m² were allocated randomly to receive standard (150 cm alimentary, 50 cm biliopancreatic limb) or distal (150 cm common channel, 50 cm biliopancreatic limb) RYGB. The primary outcome (change in BMI at 2 years) has been reported previously. Secondary outcomes 5 years after surgery, such as weight loss, health-related quality of life, and nutritional outcomes are reported.

Results

Between May 2011 and April 2013, 123 patients were randomized, 113 received an intervention, and 92 attended 5-year follow-up. Mean age was 40 (95 per cent c.i. 38 to 41) years and 73 patients (65 per cent) were women; 57 underwent standard RYGB and 56 distal RYGB. BMI was reduced by 15.1 (95 per cent c.i. 13.9 to 16.2) kg/m² after standard and 15.7 (14.5 to 16.9) kg/m² after distal RYGB; the between-group difference was −0.64 (−2.3 to 1.0) kg/m² (P = 0.447). Total cholesterol, low-density lipoprotein cholesterol, and haemoglobin A1c levels declined more after distal than after standard RYGB. High-density lipoprotein cholesterol levels increased more after standard RYGB. Vitamin A and vitamin D levels were lower after distal RYGB. Changes in bone mineral density, resting metabolic rate, and total energy intake were comparable.

Conclusion

Distal RYGB did not enable greater weight loss than standard RYGB. Differences in other outcomes favouring distal RYGB may not justify routine use of this procedure in patients with a BMI of 50–60 kg/m². Registration number: NCT00821197 (http://www.clinicaltrials.gov).

Presented in part as abstract to the IFSO (International Federation for the Surgery of Obesity and Metabolic disorders) conference, Madrid, Spain, August 2019.

Midterm Results from the Dutch Common Channel Trial (DUCATI): Superior Weight Loss Results of the Long Roux Limb Gastric Bypass in Comparison to the Standard Bypass at 3-Year Follow-Up

In the multi-center Dutch Common Channel Trial (DUCATI), a very long Roux limb Roux-en-Y gastric bypass (VLRL-RYGB: BP-limb 60 cm, Roux limb variable, and common channel 100 cm) was compared to a standard Roux-en-Y gastric bypass (S-LRYGB: BP-limb 60 cm, Roux limb 150 cm, and common channel variable) in the treatment of morbidly obese patients. As all trial patients are beyond 3-year follow-up a midterm analysis was performed to investigate the effect of the VLRL-RYGB.

METHODS

A total of 444 patients were randomized (1:1) to receive either a VLRL-RYGB or a S-LRYGB. Follow-up results for weight loss, effect on obesity-related comorbid conditions, complications, reoperation, and malnutrition are investigated.

RESULTS

At 3-year follow-up a significant difference in %TWL (34.0% vs. 31.4%, p = 0.017) and %EWL (84.7% vs. 76.6%, p = 0.043) was observed in favor of VLRL-LRYGB group. Overall complication rate 3-years after surgery was 15.8% in the VLRL-LRYGB group vs. 9% in the S-LRYGB group (p = 0.031). Eight (3.6%) patients in the VLRL-LRYGB group versus 2 (0.9%) in the S-LRYGB group (p = 0.055) required revisional surgery for malabsorption. In the VLRL-LRYGB group 71.9% of patients had resolution of T2DM versus 48.9% in the S-LRYGB group (p = 0.044).

CONCLUSION

At midterm FU a considerable, significantly increased effect on weight loss of the VLRL-LRYGB was observed compared to the S-LRYGB, with a higher risk of overall complications, but no significant nutritional side effects. These results might impact the current view on the value of the Roux limb in the discussion on optimum limb lengths in Roux-en-Y gastric bypass surgery.

Comparing a Short Biliopancreatic Limb to a Long Biliopancreatic Limb in Patients with a Roux-en-Y Gastric Bypass with 4 Years Follow-up

INTRODUCTION

In order to design the most effective weight loss procedure, the ideal biliopancreatic limb (BPL) and alimentary limb (AL) length in Roux-en-Y gastric bypass (RYGB) have been discussed extensively. Yet, no consensus has been reached. The aim of this study was to compare weight loss after a short and long BPL in patients who underwent a RYGB with a minimum of 4 years follow-up.

METHODS

This retrospective cohort study consisted of 574 patients who underwent a primary RYGB procedure between March 2015 and January 2017. Patients were divided in two groups based on the surgical procedure performed: a short BPL group (BPL of 50 cm with an AL of 150 cm) and long BPL group (BPL of 150 cm with an AL of 75 cm). The percentage total weight loss (%TWL) between groups was compared up to 4 years after surgery. Secondary outcomes were 30-day postoperative complications and health-related quality of life (RAND-36).

RESULTS

The short BPL group consisted of 286 patient and the long BPL group of 288 patients. Follow-up rates of both groups at the first, second, third, and fourth year after surgery were comparable. The long BPL group showed significantly more %TWL compared to the short BP limb group starting at 6 months (p = 0.004) until 4 years after surgery (p < 0.001). Thirty-day complications and health-related quality of life did not differ.

CONCLUSION

The results showed significantly more %TWL in patients receiving a long BPL compared to the short BPL up to 4 years after surgery.

Types, Safety, and Efficacy of Limb Distalization for Inadequate Weight Loss After Roux-en-Y Gastric Bypass: A Systematic Review and Meta-analysis With a Call for Standardized Terminology

OBJECTIVE

Comprehensive classification and evaluation of the outcome of limb distalization (LD) for inadequate weight loss after roux-en-y gastric bypass (RYGB).

BACKGROUND

Limb distalization is a revisional malabsorptive procedure for the management of inadequate weight loss after RYGB. Multiple studies with small sample sizes reported the outcome of LD. This meta-analysis aims to reach a higher level of evidence regarding the safety and efficacy of the procedure.

METHODS

A systematic search, including all studies on LD for management of inadequate weight loss after RYGB. The search engines included were PubMed, Embase, Web of Science, Cochrane Library, Scopus, and EBSCOhost.

RESULTS

Fourteen studies were included. The pooled estimates of the mid-term percentage of excess weight loss (%EWL), diabetic, and hypertension remission were 50.8%, 69.9%, and 59.8%, respectively. The rate of surgical revision for the management of protein-energy malnutrition (PEM) was 17.1%. The %EWL was significantly higher with older age and good response to index surgery (P = 0.01, 0.04, respectively). Less total alimentary limb length was not associated with better %EWL (P = 0.9), but it was significantly associated with severe PEM (P = 0.01).

CONCLUSIONS

LD has an encouraging rate of resolution of comorbidities. A judicious patient selection is essential for better weight loss after LD. Type I LD with total alimentary limb length ≥350 cm was associated with less risk of malnutrition. PEM is a life-threatening complication that may require revisional surgery years after LD. Future studies on LD, adopting standardized surgical practice and terminology, will allow a more conclusive assessment of the outcome of the procedure.

Comparison of Conventional Methods for Bowel Length Measurement in Laparoscopic Surgery to a Novel Computer-Assisted 3D Measurement System

Purpose

Accurate laparoscopic bowel length measurement (LBLM), which is used primarily in metabolic surgery, remains a challenge. This study aims to three conventional methods for LBLM, namely using visual judgment (VJ), instrument markings (IM), or premeasured tape (PT) to a novel computer-assisted 3D measurement system (BMS).

Materials and Methods

LBLM methods were compared using a 3D laparoscope on bowel phantoms regarding accuracy (relative error in percent, %), time in seconds (s), and number of bowel grasps. Seventy centimeters were measured seven times. As a control, the first, third, fifth, and seventh measurements were performed with VJ. The interventions IM, PT, and BMS were performed following a randomized order as the second, fourth, and sixth measurements.

Results

In total, 63 people participated. BMS showed better accuracy (2.1±3.7%) compared to VJ (8.7±13.7%, p=0.001), PT (4.3±6.8%, p=0.002), and IM (11±15.3%, p<0.001). Participants performed LBLM in a similar amount of time with BMS (175.7±59.7s) and PT (166.5±63.6s, p=0.35), but VJ (64.0±24.0s, p<0.001) and IM (144.9±55.4s, p=0.002) were faster. Number of bowel grasps as a measure for the risk of bowel lesions was similar for BMS (15.8±3.0) and PT (15.9±4.6, p=0.861), whereas VJ required less (14.1±3.4, p=0.004) and IM required more than BMS (22.2±6.9, p<0.001).

Conclusions

PT had higher accuracy than VJ and IM, and lower number of bowel grasps than IM. BMS shows great potential for more reliable LBLM. Until BMS is available in clinical routine, PT should be preferred for LBLM.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11695-021-05620-6.

Roux-en-Y Gastric Bypass with Long Biliopancreatic Limb Compared to Single Anastomosis Sleeve Ileal (SASI) Bypass in Treatment of Morbid Obesity

PURPOSE

Bariatric surgery is the most effective treatment of morbid obesity. Bariatric procedures employ different mechanisms of action to induce weight loss. The present study aimed to compare single-anastomosis sleeve ileal (SASI) bypass and roux-en-Y gastric bypass RYGB with long biliopancreatic limb (BPL) in terms of weight loss, remission of comorbidities, complications, and nutritional status.

METHODS

This was a single-center cohort study on patients with morbid obesity who underwent RYGB with long BPL of 150 cm or SASI bypass. The main outcome measures were weight loss and improvement in comorbidities at 12 months, nutritional status, and complications.

RESULTS

The present study included 92 patients (59.8% females) of a mean age of 38.4 years and mean BMI of 42 kg/m². RYGB and SASI bypass were followed by a significant decrease in body mass index at 12 months and were comparable in terms of excess and total weight loss. Improvement in comorbidities after the two procedures was similar. The serum albumin levels showed a significant decline after RYGB, but not after SASI bypass. The postoperative serum iron levels were higher after SASI bypass than after RYGB. There was no significant difference in regard to complication rates (13% vs 4.3%, p = 0.27).

CONCLUSIONS

RYGB with long BPL and SASI bypass achieved satisfactory weight loss and improvement in comorbidities that were comparable among the two groups. Long BPL RYGB was followed by a significant decrease in serum albumin and iron levels at one year, which was not observed after SASI bypass.

The Importance of Intestinal Length in Triglyceride Metabolism and in Predicting the Outcomes of Comorbidities in Laparoscopic Roux-en-Y Gastric Bypass-a Narrative Review

In this narrative review, we will appraise if modification of the length of bypassed small intestine based on measured total small intestinal length could optimize the outcomes of the laparoscopic Roux-en-Y gastric bypass (LRYGB). We provide a summary of carefully selected studies to serve as examples and to draw tentative conclusions of the effects of LRYGB on remission of comorbidities. As the heterogeneity of the included studies varied in terms of outcomes, type of study, length of the bypassed small intestine, and the follow-up, a common endpoint could not be defined for this narrative article. To achieve efficient metabolic outcomes, it is important to carefully choose the small intestine length excluded from the food passage suited best to each individual patient.

Long versus short biliopancreatic limb in Roux-en-Y gastric bypass: short-term results of a randomized clinical trial

BACKGROUND

The Roux-en-Y gastric bypass continues to be one of the most performed bariatric surgeries because of its adequate balance of outcomes, complications, and durability. Recently, the role of the biliopancreatic limb on weight loss and co-morbidity control has gained attention because it seems to have a positive impact based on limb length.

OBJECTIVE

To compare results at 12 months of a "standard" (group 1) versus a long (group 2) biliopancreatic limb bypass. Biliopancreatic limbs were 50 cm and 200 cm, and alimentary limbs were 150 cm and 50 cm, respectively.

SETTING

Academic Referal Center; Mexico City; Public Seeting.

METHODS

Randomized study with patients undergoing both types of surgeries at a single academic center from 2016 to 2018. The analysis included weight loss, co-morbidity control (diabetes and hypertension), biochemical panel, operative outcomes, and complications.

RESULTS

Two-hundred ten patients were included (105 in each group). Almost all data were homogenous at baseline. Female sex comprised 86.1% of cases, with a mean body mass index of 43.5 kg/m². Excess weight loss (77.6 ± 15.7% versus 83.6 ± 16.7%; P = .011) and total weight loss (33.5 ± 6.4% versus 37.1 ± 7.1%; P < .001) was higher in group 2; better HbA1C levels were also observed. Co-morbidity outcomes, operative data, and complications were similar between groups.

CONCLUSION

The Roux-en-Y gastric bypass with 200 cm of biliopancreatic limb length induces more weight loss at 12 months than a 50 cm limb length. Better HbA1C levels were also observed, but similar effects on co-morbidities and complications were noted.

Role of Gastrointestinal Hormones as a Predictive Factor for Long-Term Diabetes Remission: Randomized Trial Comparing Metabolic Gastric Bypass, Sleeve Gastrectomy, and Greater Curvature Plication

PURPOSE

Long-term studies comparing the mechanisms of different bariatric techniques for T2DM remission are scarce. We aimed to compare type 2 diabetes (T2DM) remission after a gastric bypass with a 200-cm biliopancreatic limb (mRYGB), sleeve gastrectomy (SG), and greater curvature plication (GCP), and to assess if the initial secretion of gastrointestinal hormones may predict metabolic outcomes at 5 years.

MATERIAL AND METHODS

Forty-five patients with mean BMI of 39.4(1.9)kg/m² and T2DM with HbA_1c of 7.7(1.9)% were randomized to mRYGB, SG, or GCP. Anthropometric and biochemical parameters, fasting concentrations of PYY, ghrelin, glucagon, and AUC of GLP-1 after SMT were determined prior to and at months 1 and 12 after surgery. At 5-year follow-up, anthropometrical and biochemical parameters were determined.

RESULTS

Total weight loss percentage (TWL%) at year 1 and GLP-1 AUC at months 1 and 12 were higher in the mRYGB than in the SG and GCP. TWL% remained greater at 5 years in mRYGB group - 27.32 (7.8) vs. SG - 18.00 (10.6) and GCP - 14.83 (7.8), p = 0.001. At 5 years, complete T2DM remission was observed in 46.7% after mRYGB vs. 20.0% after SG and 6.6% after GCP, p < 0.001. In the multivariate analysis, shorter T2DM duration (OR 0.186), p = 0.008, and the GLP-1 AUC at 1 month (OR 7.229), p = 0.023, were prognostic factors for complete T2DM remission at 5-year follow-up.

CONCLUSIONS

Long-term T2DM remission is mostly achieved with hypoabsortive techniques such as mRYGB. Increased secretion of GLP-1 after surgery and shorter disease duration were the main predictors of T2DM remission at 5 years.

Are There Ideal Small Bowel Limb Lengths for One-Anastomosis Gastric Bypass (OAGB) to Obtain Optimal Weight Loss and Remission of Comorbidities with Minimal Nutritional Deficiencies?

BACKGROUND

Ideal jejunal and ileal lengths in bariatric/metabolic procedures to be left in alimentary continuity still remain unclear. We aimed to evaluate different lengths of biliopancreatic limb (BPL) and common limb (CL) performed in a series of patients submitted to OAGB, and correlate them with weight loss and nutritional deficits.

PATIENTS AND METHODS

A prospective observational study of 350 consecutive morbidly obese patients undergoing OAGB was performed. BPL and CL lengths were determined intraoperatively; BPL/TBL and CL/TBL ratios were then calculated. Anthropometric variables, remission of comorbidities and specific supplementation needs were recorded at 1, 2 and 5 years after surgery.

RESULTS

Three hundred patients were included for final analysis. BPL length and BPL/TBL ratio directly correlated with Units of BMI lost (UBMIL). Conversely, CL length and CL/TBL ratio showed an inverse correlation with UBMIL. Establishing a BMI ≤ 25 kg/m² as ideal, the most accurate AUC, to predict achieving an ideal BMI at 1, 2 and 5 years after surgery, was obtained for the CL/TBL ratio, followed by the CL length at 1, 2 and 5 years. An ideal range was established between 0.40 and 0.43 for the CL/TBL ratio, and 200 to 220 cm for the CL length. Among these ranges, there were no cases of protein or calorie malnutrition.

CONCLUSION

TBL measurement is essential to obtain optimal outcomes after OAGB, both in terms of excellent weight loss and remission/improvement of comorbidities, as well as with a low risk of nutritional deficiencies. The CL/TBL ratio, followed by CL length, are the most accurate parameters to predict a 5-year postoperative BMI ≤ 25 kg/m².

Variables Associated with Short-Term Weight Loss in a Cohort of Patients with Morbid Obesity According to Age and Three Types of Bariatric Surgery

Background The percentage of excess weight lost (%EWL) after bariatric surgery (BS) shows great discrepancies from one individual to another. Objective To evaluate the %EWL one year after BS and to determine the existence of baseline biomarkers associated with weight loss. Methods We studied 329 patients with morbid obesity undergoing three types of BS (biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG)), depending on the %EWL one year after surgery: good responders (GR) (%EWL ≥ 50%) and non-responders (NR) (%EWL < 50%). Results The GR presented a higher percentage of change in anthropometric and biochemical variables compared to the NR group, even within each type of BS. There was a greater percentage of GR among those who underwent RYGB. The patients who underwent SG showed the lowest decrease in biochemical variables, both in GR and NR. Within the GR group, those with a lower age showed greater improvement compared to the other age groups. A %EWL ≥50% was negatively associated with the age and atherogenic index of plasma (AIP), and positively with the type of BS (RYGB). Conclusions The GR group was associated with lower age and AIP and undergoing RYGB. Additionally, those patients who underwent SG showed a lower metabolic improvement.

Short versus long biliopancreatic limb in Roux-en-Y gastric bypass surgery for treatment of type 2 diabetes mellitus

Introduction

Although laparoscopic Roux-en-Y gastric bypass (RYGB) is still widely accepted as a valid procedure in the treatment of obesity and type 2 diabetes mellitus (T2DM), there continues to be a significant controversy about how long the Roux and biliopancreatic limb should be bypassed for optimum results.

Aim

To assess the effect of a longer biliopancreatic limb (BPL) length on glycemic control after RYGB in T2DM patients.

Material and methods

Eighty-four patients with uncontrolled T2DM who underwent RYGB between May 2010 and April 2017 were collected from the prospectively designed database. Forty patients (S-BPL group) received BPL lengths ≤ 50 cm, including 30 cm (n = 1), 40 cm (n = 1), and 50 cm (n = 38). Forty-four patients (L-BPL group) received 100 cm BPL. Anthropometry, serum glucose and lipid metabolic parameters were measured at baseline and 1, 3, 6, 12, 24 and 36 months after surgery.

Results

Comparing the two groups, there were no significant differences in anthropometric and biochemical measures, except the weight and body mass index, which were higher in the S-BPL group (85.91 ±20.32 vs. 76.25 ±16.99, p = 0.038; 31.87 ±6.61 vs. 28.7 ±4.29, p = 0.005) compared to the L-BPL group. The body weight, glucose and lipid metabolic parameters decreased over time and then remained essentially stable from the first year in both groups. Two years after surgery, the remission (HbA_1c% ≤ 6%) of T2DM was 31.2% in the S-BPL group and 37.5% in the L-BPL group (p = 0.685).

Conclusions

With consistent total small bowel bypass (AL + BPL) lengths, lengthening of the BPL from 30 to 100 cm did not affect the post-RYGB glycemic control and weight loss.

The Influence of Different Alimentary and Biliopancreatic Limb Lengths in Gastric Bypass Patients

PURPOSE

The aim of this study was to compare the effect of two different limb lengths after RYGB on weight loss, postoperative gastro-intestinal complications, and vitamin deficiencies.

MATERIALS AND METHODS

A retrospective analyses of 100 patients after RYGB with 2 different limb lengths were done. Group A (50 patients) had a biliopancreatic limb (BPL) of 75 cm and an alimentary limb (AL) of 150 cm. Group B (50 patients) had a BPL of 150 cm and an AL of 75 cm. The effect on weight loss, body mass index, excess weight loss (EWL), total weight loss (TWL), and postoperative complications was analyzed up to 2 years postoperatively.

RESULTS

Patients with a longer BPL achieved significantly more %EWL compared to a shorter BPL 2 years postoperatively (82.8 ± 31.2 versus 93.8 ± 15.1; p = 0.038). A significant difference was also seen in %TWL after 1 year (30.3 ± 10.1 versus 37.4 ± 6.9; p < 0.01) and 2 years (31.6 ± 7.5 versus 35.6 ± 8.6; p = 0.022), both in favor of group B. However, patients with a longer BPL (group B) showed significant more diarrhea and steatorrhea compared to group A (p < 0.01).

CONCLUSION

BPL of 150 cm is associated with more %EWL and %TWL 2 years after RYGB. However, it is accompanied by an increase of diarrhea and steatorrhea to disadvantage off group B. Future studies need to focus on further tailoring BPL and AL lengths to achieve the best possible outcomes for patients with morbid obesity.

Does the Length of the Common Channel as Part of the Total Alimentary Tract Matter? One Year Results from the Multicenter Dutch Common Channel Trial (DUCATI) Comparing Standard Versus Distal Roux-en-Y Gastric Bypass with Similar Biliopancreatic Bowel Limb Lengths

PURPOSE

Although the laparoscopic Roux-en-Y Gastric Bypass (LRYGB) is the gold-standard bariatric procedure, it remains uncertain what the optimal bowel limb lengths are to accomplish maximal weight loss while minimizing nutritional deficiencies and related gastro-intestinal complaints. The aim of this randomized controlled multicenter trial is to investigate the effect of significant lengthening of the length of the Roux limb (RL) at the cost of the length of the common channel (CC) while keeping the biliopancreatic limb (BPL) lengths the same on both study arms.

METHODS

Four hundred forty-four patients were randomized to receive either a Very Long Roux Limb LRYGB (VLRL-LRYGB) (variable RL length, BPL 60 cm, and CC 100 cm) or a Standard LRYGB (S-LRYGB) (RL 150 cm, BPL 60 cm, and a variable CC length). Results at 1-year follow-up for weight loss, effect on obesity-related comorbid conditions, complications, re-operation rate, malnutrition rate, and re-admission rate were investigated.

RESULTS

Weight loss at 1-year showed no significant differences for %EWL (84.3% versus 85.3%, p = 0.72) and %TWL (34.2% versus 33.6%, p = 0.359) comparing VLRL-LRYGB versus S-LRYGB. Malabsorption requiring surgical bowel length adjustment was observed in 1.4% in VLRL-LRYGB group versus 0.9% in S-LRYGB group (p = 0.316).

CONCLUSION

Significant lengthening of the RL at the cost of the common channel seems to have no effect on the weight loss at 1-year follow-up, which supports the theory that absorption of nutrients also occurs in the RL. Nevertheless, long-term results of the VLRL-LRYGB have to be awaited to draw final conclusions as part of the discussion towards optimal limb length in LRYGB surgery.

Effect of different limb lengths on quality of life, eating patterns and gastrointestinal symptoms after Roux-en-Y gastric bypass in superobese patients: randomized study

BACKGROUND

Distal Roux-en-Y gastrojejunal bypass (DRYGJB) gives better weight reduction than standard Roux-en-Y gastric bypass (RYGB) but at the risk of increased malnutrition side-effects. This study compared the effects of RYGB and DRYGJB on gastrointestinal symptoms, eating patterns and health-related quality of life (QoL).

METHODS

This was a single-blind RCT from a university-affiliated obesity centre. Patients with a BMI of 50 kg/m2 or above were invited to participate. Treatment arms were standard gastric bypass with an alimentary limb of 150 cm and a biliopancreatic limb of 60 cm, with a variable common channel length, or DRYGJB with biliopancreatic limb of 200 cm, common channel limb of 150 cm and variable alimentary limb length. Baseline and follow-up data to 5 years on quality of life, obesity-related problems and gastrointestinal symptoms were collected using prospectively created and validated questionnaires.

RESULTS

Some 140 patients were included. Those with a DRYGJB had better weight loss at 5 years (mean(s.d.) 68·3(21·8) kg versus 55·7(19·8) kg for standard RYGB; P = 0·011). Eating patterns improved, with no difference between the groups. Gastrointestinal symptoms (diarrhoea, indigestion) worsened significantly in both groups, but only patients with DRYGJB had significantly worse diarrhoea at the end of the study than at baseline (P = 0·006). Both groups had improved perceived generic QoL over baseline, and obesity-related problems were markedly reduced.

CONCLUSION

Standard RYGB and both improved generic and disease-specific QoL and eating behavioural pattern. Diarrhoea was increased more following DRYGJB than after RYGB. Registration number: NCT01514799 (https://clinicaltrials.gov).

Changes in bowel habits after laparoscopic sleeve gastrectomy

Introduction

Bariatric surgery has a significant impact on dietary intake, weight loss, patient’s metabolism and also on defaecation stereotypes.

Aim

To investigate changes in bowel habits of morbidly obese patients after laparoscopic sleeve gastrectomy (LSG).

Material and methods

This was a prospective clinical cohort study conducted to assess changes in bowel habits after LSG in a single institution.

Results

In total, 124 patients were enrolled in the study (age 47.1 ±11.2 years, body mass index (BMI) 44.3 ±6.8 kg/m²). The mean weight loss 6 months after LSG was 29.1 ±11.1 kg; percentage excess weight loss was 56.2 ±20.4%. Before surgery, 35.5% of patients had constipation and 6.5% of patients had faecal incontinence (FI). No correlation was found between rising level of BMI and constipation or incontinence prevalence/severity. Data analysis has not confirmed increased prevalence/severity of postoperative constipation or incontinence 6 months after LSG. Out of the group of patients with preoperative constipation, clinically relevant improvement was noted in 45.5% of patients after the surgery. Among patients without constipation before surgery, impairment was noted in 21.2% of patients. Out of the group of patients with preoperative incontinence, improvement was found in 37.5% of patients; none of these patients reported clinically relevant impairment of incontinence symptoms.

Conclusions

The present study has not revealed increased prevalence/severity of postoperative constipation or anal incontinence 6 months after LSG. Our findings suggest that weight loss in patients after LSG might be associated with an improvement of constipation symptoms of individual patients.

Conventional Versus Distal Laparoscopic One-Anastomosis Gastric Bypass: a Randomized Controlled Trial with 1-Year Follow-up

BACKGROUND

There is no consensus on the ideal small bowel length that should be bypassed in laparoscopic one-anastomosis gastric bypass (OAGB). This study aimed to compare the safety and efficacy of conventional versus distal techniques of laparoscopic OAGB.

METHODS

This randomized controlled trial involved 60 adults with morbid obesity scheduled for laparoscopic OAGB randomly assigned to one of the two techniques; conventional technique (fixed anastomosis 200 cm from the ligament of Treitz) and distal technique (anastomosis 400 cm from the ileocecal valve). Total small bowel length (TSBL) was measured in all cases. Quality of life was assessed using the Gastrointestinal Quality of Life Index (GIQLI). Outcome measures were excess body weight loss percentage (EBWL%), resolution of associated comorbidities, frequency of nutritional deficiencies, and quality of life.

RESULTS

No patients were lost to follow-up. The two groups were comparable in TSBL, EBWL%, and complete resolution of comorbidities up to 12 months. The percentage of afferent loop length to TSBL was significantly higher in the distal group (p < 0.001) but was not correlated with EBWL%. The levels of hemoglobin, cholesterol, triglycerides, iron, and albumin were significantly lower and parathormone hormone was higher in the distal group. The GIQLI score was significantly higher in the conventional group during follow-up.

CONCLUSION

OAGB achieves optimum results when the afferent loop length is 200 cm; bypassing more than 200 cm does not improve weight loss or comorbidity resolution. Measuring TSBL is recommended to avoid excessive small bowel shortening that increases the risk of nutritional consequences.

Impact of Biliopancreatic Limb Length (70 cm vs 120 cm), with Constant 150 cm Alimentary Limb, on Long-Term Weight Loss, Remission of Comorbidities and Supplementation Needs After Roux-En-Y Gastric Bypass: a Prospective Randomized Clinical Trial

BACKGROUND

The best alimentary and biliopancreatic limb (BPL) lengths in the Roux-en-Y gastric bypass (RYGB) still remain unclear. The aim of this study was to compare the effect of a BPL of 70 vs 120 cm, with a constant AL of 150 cm on long-term weight loss, remission of comorbidities, and supplementation needs after RYGB.

PATIENTS AND METHODS

A prospective randomized study of morbidly obese patients undergoing RYGB was performed. Patients were randomized into two groups: those patients undergoing RYGB with a BPL of 70 cm (BPL 70 cm) and those ones undergoing RYGB with a BPL of 120 cm (BPL 120 cm). BMI, excess BMI loss (EBMIL), remission of comorbidities and specific vitamin and mineral supplementation needs at 1, 2, and 5 years were analyzed.

RESULTS

Two hundred fifty-three patients were included in each group. There were no significant differences in BMI, EBMIL and the remission of diabetes mellitus, hypertension, and dyslipidemia between groups at 1, 2, and 5 years after surgery. Patients from group BPL 120 cm required greater specific supplementation of vitamin B12, folic acid, and vitamin A during all the follow-up.

CONCLUSION

A RYGB with 120 cm BPL does not achieve greater weight loss or remission of comorbidities than a RYGB with 70 cm BPL but is associated with greater deficiencies of vitamin B12, vitamin A, and folic acid.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT03607305. https://clinicaltrials.gov/.

Revision of Roux-en-Y Gastric Bypass with Limb Distalization for Inadequate Weight Loss or Weight Regain

BACKGROUND

Of patients undergoing Roux-en-Y gastric bypass (RYGB), 15-35% of patients fail to achieve "adequate" weight loss or regain significant weight. Multiple solutions have been proposed, but not well studied. We report our experience with limb distalization with lengthening the biliopancreatic (BP) limb and shortening the common channel (CC).

METHODS

We retrospectively reviewed data from patients undergoing laparoscopic limb distalization for excess weight loss (EWL) <50% or BMI >35 kg/m² after RYGB from 2012 to 2017. The BP limb was lengthened and CC was shortened to 100-200 cm. Perioperative outcomes such as morbidity, weight loss, nutritional deficiencies, comorbidity remission, and operative details were analyzed.

RESULTS

Twenty-two patients were included. The mean BMI prior to RYGB was 54.1 ± 8.5 kg/m² and 43.0 ± 5.5 kg/m² prior to limb distalization. The mean follow-up was 18.3 ± 12.9 months with a mean BMI change, %EWL, and %TWL (total weight loss) of 11.8 ± 7.4 kg/m², 62.3 ± 32.4%, and 25.4 ± 14.4%, respectively. The total mean BMI change, %EWL, and %TWL from RYGB was 22.2 ± 9.9 kg/m², 77.8 ± 23.6%, and 40.2 ± 13.3%, respectively. Of patients with persistent comorbidities, remission rates of diabetes, hypertension, and gastroesophageal reflux disease were 100%, 17%, and 38%, respectively. The mean operative time was 132.6 ± 54.4 min and mean hospital stay was 2.2 ± 1.3 days. Overall morbidity was 27.3%. Three patients (13.6%) developed nutritional deficiencies requiring reversal surgery.

CONCLUSION

In patients with inadequate weight loss or weight regain after RYGB, limb distalization with lengthening of the BP limb is an effective procedure for additional weight loss and further improvement of comorbidities. Nutritional complications are a risk, but can be minimized with close follow-up and patient compliance.

"Dysfunctions" induced by Roux-en-Y gastric bypass surgery are concomitant with metabolic improvement independent of weight loss

Metabolic surgery has been increasingly recommended for obese diabetic patients, but questions remain as to its molecular mechanism that leads to improved metabolic parameters independently of weight loss from a network viewpoint. We evaluated the role of the Roux limb (RL) in Roux-en-Y gastric bypass (RYGB) surgery in nonobese diabetic rat models. Improvements in metabolic parameters were greater in the long-RL RYGB group. Transcriptome profiles reveal that amelioration of diabetes state following RYGB differs remarkably from both normal and diabetic states. According to functional analysis, RYGB surgery significantly affected a major gene group, i.e., the newly changed group, which represented diabetes-irrelevant genes abnormally expressed after RYGB. We hypothesize that novel "dysfunctions" carried by this newly changed gene group induced by RYGB rebalance diabetic states and contribute to amelioration of metabolic parameters. An unusual increase in cholesterol (CHOL) biosynthesis in RL enriched by the newly changed group was concomitant with ameliorated metabolic parameters, as demonstrated by measurements of physiological parameters and biodistribution analysis using [14C]-labeled glucose. Our findings demonstrate RYGB-induced "dysfunctions" in the newly changed group as a compensatory role contributes to amelioration of diabetes. Rather than attempting to normalize "abnormal" molecules, we suggest a new disease treatment strategy of turning "normal" molecules "abnormal" in order to achieve a new "normal" physiological balance. It further implies a novel strategy for drug discovery, i.e. targeting also on "normal" molecules, which are traditionally ignored in pharmaceutical development.

Weight loss after one-anastomosis/mini-gastric bypass - The impact of biliopancreatic limb: A retrospective cohort study

Background

One-anastomosis/mini-gastric bypass (OAGB/MGB), as a popular bariatric surgery method, has many advantages; however, the biliopancreatic limb length (BPL) in this surgery is under debate. The aim of the study was to evaluate the effect of BPL on weight-loss outcome after OAGB/MGB.

Materials and Methods

A retrospective cohort study was performed on 653 patients who underwent OAGB/MGB with adjusted BPL based on preoperative body mass index (BMI) and patient's age, between 2010 and 2015 with 12-month follow-ups. Weight-loss outcomes and complications were analyzed in these patients, considering BPL.

Results

Weight, age, sex, and type 2 diabetes mellitus were the most contributory predictors as independent predictors of 12-month excess weight loss, respectively, and BPL was the least contributory predictor.

Conclusion

Tailoring BPL in OAGB/MGB based on patient's age and preoperative BMI seems to have acceptable results.

Bariatric Surgery in Obesity: Effects on Gut Microbiota and Micronutrient Status

Obesity is associated with reduced gut microbial diversity and a high rate of micronutrient deficiency. Bariatric surgery, the therapy of choice for severe obesity, produces sustained weight loss and improvements in obesity-related comorbidities. Also, it significantly alters the gut microbiota (GM) composition and function, which might have an important impact on the micronutrient status as GM is able to synthesize certain vitamins, such as riboflavin, folate, B12, or vitamin K2. However, recent data have reported that GM is not fully restored after bariatric surgery; therefore, manipulation of GM through probiotics represents a promising therapeutic approach in bariatric patients. In this review, we discuss the latest evidence concerning the relationship between obesity, GM and micronutrients, the impact of bariatric surgery on GM in relation with micronutrients equilibrium, and the importance of the probiotics' supplementation in obese patients submitted to surgical treatment.

Proximal Roux-en-Y gastric bypass: Addressing the myth of limb length

BACKGROUND

Some studies suggest that changes in weight or metabolic outcomes are affected by the lengths of the gastrointestinal limbs in the Roux-en-Y gastric bypass.

METHODS

Participants (N = 1,770) underwent primary Roux-en-Y gastric bypass and were followed ≤7 years in the Longitudinal Assessment of Bariatric Surgery-2, a multicenter US cohort study. Alimentary limb and biliopancreatic limb lengths were measured according to research protocol; common channel was measured in a subsample (N = 547). Aimentary limb, biliopancreatic limb, and common channel ratio to total small bowel length were calculated.

RESULTS

Median presurgery body mass index was 46 (25th-75th percentile: 43-51) kg/m2. Medians (25th-75th percentiles) for alimentary limb length were 125 cm (100-150), for biliopancreatic limb length were 50 cm (50-60), and common channel length were 410 cm (322-520). Statistics for ratios to the small bowel length were 0.23 (0.18-0.27) for alimentary limb, 0.09 (0.07-0.10) for biliopancreatic limb, and 0.69 (0.63-0.73) for common length. There were no significant associations between alimentary limb, biliopancreatic limb, common channel, alimentary limb ratio, biliopancreatic limb ratio or common channel ratio, and either weight loss or improvement in cardiometabolic outcomes.

CONCLUSION

The common channel length in Roux-en-Y gastric bypass is highly variable between individuals. None of the limb lengths in this study, nor alimentary limb, biliopancreatic limb, or common channel ratios, seem to be related to weight loss or metabolic improvements >7 years.

Change in gastrointestinal symptoms over the first 5 years after bariatric surgery in a multicenter cohort of adolescents

BACKGROUND

Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) are effective for weight loss in adolescents with severe obesity. However, little is known about adverse gastrointestinal symptoms (GIS) following these operations in adolescents. The objective was to examine GIS over 5 years after surgery and differences by surgery type.

METHODS

We prospectively studied 228 adolescents (161 RYGB, 67 VSG) undergoing bariatric surgery. Gastrointestinal symptoms were assessed before surgery, at 6-months, and yearly to 5 years after surgery. Symptom severity was dichotomized for analysis. Analysis of post-surgery symptoms involved linear models adjusting for baseline symptoms, BMI, early post-operative complication, sex, and race.

RESULTS

Participants at surgery were 17 ± 1.6 years with preoperative BMI 53 ± 9.4 kg/m². From 6 months to 5 years, gastroesophageal reflux symptoms (GERS), nausea, bloating, and diarrhea increased. Crude prevalence rates of GERS increased from 4% (1% RYGB, 11% VSG) at 6-months post-surgery to 14% (10% RYGB, 26% VSG) at 5-years. In adjusted analyses, the VSG group experienced 4-fold (4.85 95% CI 2.63, 8.91, p < 0.0001) greater odds of GERS compared to RYGB.

CONCLUSIONS

Adolescents who underwent VSG experienced greater risk of GERS compared to those undergoing RYGB. Adolescents undergoing VSG should be counseled preoperatively about GERS and objectively monitored postoperatively for gastroesophageal reflux when indicated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, Identifier: NCT00474318, https://clinicaltrials.gov/ct2/show/NCT00474318?term=Teen-LABS&rank=1.

TYPE OF STUDY

Treatment Study.

LEVEL OF EVIDENCE

Level II.

A Meta-Analysis of GLP-1 After Roux-En-Y Gastric Bypass: Impact of Surgical Technique and Measurement Strategy

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is an effective treatment for diabetes. Glucagon-like peptide-1 (GLP-1) is a gut hormone that is important to glucose homeostasis.

OBJECTIVE

This study aimed to assess GLP-1 level and its predictors after RYGB.

METHODS

The study design was a meta-analysis. The data sources were MEDLINE, EMBASE, Web of Science, and the Cochrane Databases. The study selection composed of studies with pre- and post-RYGB levels. The main outcomes were as follows: Primary outcome was the change in postprandial GLP-1 levels after RYGB. Secondary outcomes included the changes in fasting glucose, fasting insulin, and fasting GLP-1 levels after RYGB. Meta-regression to determine predictors of changes in GLP-1 levels was performed. Outcomes were reported using Hedge's g.

RESULTS

Twenty-four studies with 368 patients were included. Postprandial GLP-1 levels increased after RYGB (Hedge's g = 1.29, p < 0.0001), while fasting GLP-1 did not change (p = 0.23). Peak postprandial GLP-1 levels gave the most consistent results (I ² = 9.11). Fasting glucose and insulin levels decreased after RYGB (p < 0.0001). Roux limb length was a significant predictor for amount of GLP-1 increase (β = - 0.01, p = 0.02). Diabetes status, amount of weight loss, length of biliopancreatic limb, and time of measurement were not significant predictors (p > 0.05).

CONCLUSION

Postprandial GLP-1 levels increase after RYGB, while fasting levels remain unchanged. Shorter Roux limb length is associated with greater increase in postprandial GLP-1, which may lead to better glycemic control in this population.

Patient-Reported Outcome Measures 2 Years After Standard and Distal Gastric Bypass-a Double-Blind Randomized Controlled Trial

BACKGROUND

The preferred surgical procedure for treating morbid obesity is debated. Patient-reported outcome measures (PROMs) are relevant for evaluation of the optimal bariatric procedure.

METHODS

A total of 113 patients with BMI from 50 to 60 were randomly assigned to standard (n = 57) or distal (n = 56) Roux-en-Y gastric bypass (RYGB). Validated PROMS questionnaires were completed at baseline and 2 years after surgery. Data were analyzed using mixed models for repeated measures and the results are expressed as estimated means and mean changes.

RESULTS

Obesity-related quality of life improved significantly after both procedures, without significant between-group differences (- 0.4 (95% CI = - 8.4, 7.2) points, p = 0.88, ES = 0.06). Both groups had significant reductions in the number of weight-related symptoms and symptom distress score, with a mean group difference (95% CI) of 1.4 (- 0.3, 3.3) symptoms and 5.0 (2.9. 12.8) symptom distress score points. There were no between-group differences for uncontrolled eating (22.0 (17.2-26.7) vs. 28.9 (23.3-34.5) points), cognitive restraint (57.4 (52.0-62.7) vs. 62.1 (57.9-66.2) points), and emotional eating (26.8 (20.5-33.1) vs. 32.6 (25.5-39.7) points). The prevalence of anxiety was 33% after standard and 25% after distal RYGB (p = 0.53), and for depression 12 and 9%, respectively (p = 0.76).

CONCLUSIONS

There were no statistically significant differences between standard and distal RYGB 2 years post surgery regarding weight loss, obesity-related quality of life, weight-related symptoms, anxiety, depression, or eating behavior.

TRIAL REGISTRATION

Clinical Trials.gov number NCT00821197.

Small Intestinal Length Associates with Serum Triglycerides Before and After LRYGB

BACKGROUND AND AIMS

Different bariatric procedures have been associated with variable weight loss and decrease in serum levels of lipids and lipoproteins. This variation could be partly related to the length of the small intestinal bypass. We evaluated the association of the small intestinal length with the non-alcoholic fatty liver disease (NAFLD) at baseline and with lipid metabolism before and after laparoscopic Roux-en-Y gastric bypass (LRYGB).

METHODS

Seventy consecutive morbidly obese patients were recruited to this prospective study. A standard 60-cm biliopancreatic limb (BPL) and 120-cm alimentary limb (AL) was performed, and thereafter, the common channel (CC) length was measured during elective LRYGB. Histological analysis of liver biopsy to diagnose NAFLD was performed. The mRNA expression of genes participating in the cholesterol and fatty acid metabolism in the liver was analyzed.

RESULTS

Female sex (p = 0.006), serum triglycerides (TG, p = 0.016), serum alanine aminotransferase (ALT, p = 0.007), and liver steatosis (p = 0.001) associated with the small intestinal length (BPL + AL + CC) at baseline. Association remained significant between levels of serum TG and CC length (p = 0.048) at 1-year follow-up. Liver mRNA expression of genes regulating cholesterol synthesis and bile metabolism did not associate with the baseline small intestinal length.

CONCLUSIONS

Our findings support the suggestions that small intestinal length regulates TG metabolism before and after LRYGB. Therefore, modification of the length of bypassed small intestine based on measured total small intestinal length could optimize the outcomes of the elective LRYGB.

The importance of the biliopancreatic limb length in gastric bypass: A systematic review

BACKGROUND

Bariatric surgery has proven to be the most durable treatment for obesity, and it also provides improvement of obesity's associated co-morbidities. Although several mechanisms for its metabolic effects have been studied, the implications of the surgically constructed anatomy on its functioning physiology have not been elucidated. This leaves some uncertainty regarding the recommended limb lengths in Roux-en-Y gastric bypass. The alimentary limb length and function has been studied extensively, but few have studied the influences of the biliopancreatic limb length.

OBJECTIVE

To present a systematic review of the literature comparing variations in length of BP limb and results in order to determine BP limb length influence.

SETTING

Academic Hospital, United States.

METHODS

We present a systematic review of all the articles comparing variations of the biliopancreatic limb length and their results.

RESULTS

Thirteen articles were identified and analyzed. Most of the articles are prospective studies. Weight loss was superior in longer limbs.

CONCLUSION

Based on our review of the subject, we can conclude that the release of enterohormones in response to a food load in the distal small bowel seems to play an important role in the remission of co-morbidities. Hence, the length of the biliopancreatic limb might affect this process.

Long-limb length difference had no effect on outcomes of laparoscopic Roux-en-Y gastric bypass surgery for obese Chinese patients with type 2 diabetes mellitus: A CONSORT compliant article

Bariatric surgery is effective in treating different components of metabolic syndrome including obesity, type 2 diabetes mellitus (T2DM), and hyperlipidemia. But there is no consensus on the ideal biliopancreatic and Roux limb length. This study aimed to explore the effect of biliopancreatic limb and Roux limb lengths during laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures on weight loss and T2DM control.We studied the clinical records of 58 patients with metabolic syndrome, T2DM, and body mass index (BMI) 32 to 50 kg/m who underwent LRYGB in our hospital. The short limb group (Group A) underwent LRYGB with a limb length of 160 to 200 cm (n = 31) and the long limb group (Group B) underwent LRYGB with a limb length of 210 to 240 cm (n = 27) were compared.The occurrence of acute or chronic internal hernia in Group B was higher than that in Group A (P = .026). Twelve months after surgery, patients from the 2 groups were also observed with reduction in BMI, percent excess weight loss (EWL), preoperative FPG, and HbA1c as compared with these indicators before surgery. However, the differences of these indicators between 2 groups were not significant at the time point of before and 3, 6, 12 months after surgery.LRYGB had significant effects on weight loss and diabetes control in obese T2DM patients. However, there was no significant difference in the short term on weight loss and diabetes control in the patients receiving different limb lengths.

Computer-assisted 3D bowel length measurement for quantitative laparoscopy

BACKGROUND

This study aimed at developing and evaluating a tool for computer-assisted 3D bowel length measurement (BMS) to improve objective measurement in minimally invasive surgery. Standardization and quality of surgery as well as its documentation are currently limited by lack of objective intraoperative measurements. To solve this problem, we developed BMS as a clinical application of Quantitative Laparoscopy (QL).

METHODS

BMS processes images from a conventional 3D laparoscope. Computer vision algorithms are used to measure the distance between laparoscopic instruments along a 3D reconstruction of the bowel surface. Preclinical evaluation was performed in phantom, ex vivo porcine, and in vivo porcine models. A bowel length of 70 cm was measured with BMS and compared to a manually obtained ground truth. Afterwards 70 cm of bowel (ground truth) was measured and compared to BMS.

RESULTS

Ground truth was 66.1 ± 2.7 cm (relative error + 5.8%) in phantom, 65.8 ± 2.5 cm (relative error + 6.4%) in ex vivo, and 67.5 ± 6.6 cm (relative error + 3.7%) in in vivo porcine evaluation when 70 cm was measured with BMS. Using 70 cm of bowel, BMS measured 75.0 ± 2.9 cm (relative error + 7.2%) in phantom and 74.4 ± 2.8 cm (relative error + 6.3%) in ex vivo porcine evaluation. After thorough preclinical evaluation, BMS was successfully used in a patient undergoing laparoscopic Roux-en-Y gastric bypass for morbid obesity.

CONCLUSIONS

QL using BMS was shown to be feasible and was successfully translated from studies on phantom, ex vivo, and in vivo porcine bowel to a clinical feasibility study.

Customization of biliopancreatic limb length to modulate and sustain antidiabetic effect of gastric bypass surgery

Although Roux-en-Y Gastric Bypass (RYGB) remains the most effective treatment for obesity and type 2 diabetes (T2D), many patients fail to achieve remission, or relapse. Increasing intestinal limb lengths of RYGB may improve outcomes, but the mechanistic basis for this remains unclear. We hypothesize biliopancreatic (BP) limb length modulates the antidiabetic effect of RYGB. Rats underwent RYGB with a 20-cm (RYGB-20cm) or 40-cm (RYGB-40cm) BP limb and were compared with control animals. After 2 and 4 wk, portal and systemic blood was sampled during intestinal glucose infusion. Portosystemic gradient was used to calculate intestinal glucose utilization (G_util), absorption (G_absorp), and hormone secretion. Intestinal morphology and gene expression were assessed. At 2 wk, G_absorp progressively decreased with increasing BP limb length; this pattern persisted at 4 wk. G_util increased ≈70% in both RYGB-20cm and -40cm groups at 2 wk. At 4 wk, G_util progressively increased with limb length. Furthermore, Roux limb weight, and expression of hexokinase and preproglucagon, exhibited a similar progressive increase. At 4 wk, glucagon-like peptide-1 and -2 levels were higher after RYGB-40cm, with associated increased secretion. We conclude that BP limb length modulates multiple antidiabetic mechanisms, analogous to the dose-response relationship of a drug. Early postoperatively, a longer BP limb reduces G_absorp. Later, G_util, Roux limb hypertrophy, hormone secretion, and hormone levels are increased with longer BP limb. Sustained high incretin levels may prevent weight regain and T2D relapse. These data provide the basis for customizing BP limb length according to patient characteristics and desired metabolic effect. NEW & NOTEWORTHY Biliopancreatic limb length in gastric bypass modulates multiple antidiabetic mechanisms, analogous to the dose-response relationship of a drug. With a longer biliopancreatic limb, Roux limb hypertrophy, increased glucose utilization, reduced glucose absorption, and sustained high incretin levels may prevent weight regain and diabetes relapse.

Common Limb Length Does Not Influence Weight Loss After Standard Laparoscopic Roux-En-Y Gastric Bypass

BACKGROUND

Although Roux-en-Y gastric bypass (RYGBP) has proven its reliability over time in terms of weight loss and resolution of comorbidities, there continues to be a significant controversy in terms of used limb lengths. In the classical RYGBP, most surgeons have reported an alimentary limb length (ALL) of 100 to 150 cm and a bilio-pancreatic limb length (BPLL) of 50 to 75 cm. On the other hand, the common limb length (CLL) remains unknown in all the patients. As it is theoretically related to the level of malabsorption, CLL could influence weight loss after RYGBP.

MATERIALS AND METHODS

We performed a laparoscopic RYGBP in 90 patients with a mean preoperative body mass index (BMI) of 44.8. ALL and BPLL were respectively fixed at 150 and 75 cm. A systematic intraoperative measurement of CLL was performed.

RESULTS

As expected, we found a great variation of the jejuno-ileal length and also of the CLL. We created three subgroups of patients: one with the entire population, one excluding the super-obese patients (BMI > 50) and the third one excluding the revisions. There was no statistically significant correlation between CLL and excess BMI loss (EBMIL) at 1, 3, 6 and 12 months of follow-up in each group. We also found a linear correlation between the jejuno-ileal length and the height of individuals.

CONCLUSION

With a fixed 150-cm ALL and a 75-cm BPLL, there is no evidence that the anatomical variations of CLL could influence weight loss after classical RYGBP.

Single-Anastomosis Pylorus-Preserving Bariatric Procedures: Review of the Literature

Single-anastomosis pylorus-preserving procedures (SAPPP) were recently introduced into bariatric surgery in order to combine the physiologic advantages of a post-pyloric reconstruction with the technical advantages of an omega loop. Surgery consists of a sleeve gastrectomy that is performed first, followed by a duodeno-enterostomy. Two main variants exist: proximal and distal SAPPP, with duodeno-jejunostomy and duodeno-ileostomy, respectively. This review describes the SAPPP reported in the literature and analyzes their outcomes in comparison with the most frequently performed bariatric techniques. Preliminary results appear as promising in terms of both safety and effectiveness on weight loss and comorbidities improvement.

Predictors of Excess Weight Loss in Obese Patients After Gastric Bypass: a 60-Month Follow-up

BACKGROUND

The objective of this study was to analyze the factors associated with change in body mass index (BMI) and with percentage of excess weight loss (%EWL) in patients undergoing Roux-en-Y gastric bypass (RYGB). The following factors were analyzed: sex, age, surgical access (laparotomy vs. laparoscopy), preoperative BMI, waist circumference (WC), type 2 diabetes mellitus (T2DM), high blood pressure, and dyslipidemia.

METHODS

Retrospective cohort study using a convenience sample of 2070 patients of both sexes, aged 18 to 65 years, undergoing RYGB between 2000 and 2013. The outcomes of interest were BMI and %EWL at 0, 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 months after RYGB.

RESULTS

After 36, 48, and 60 months, approximately 50 % of patients had BMI >30 kg/m(2). As for %EWL, 60-month results were poor for 17 % of patients (%EWL <50 %), good for 40 % of patients (%EWL 50-75 %), very good for 24 % of patients (%EWL from >75-90 %), and excellent for 19 % of patients (%EWL >90 %). The four most significant predictors of BMI change 60 months after RYGB (in descending order of magnitude) were preoperative BMI, preoperative WC, surgical access, and age; and of %EWL, surgical access, preoperative BMI, preoperative WC, and age.

CONCLUSIONS

After 60 months of follow-up, the most relevant predictors of weight loss after RYGB were lower preoperative BMI and WC, videolaparoscopy as surgical access, and younger age. Further studies must be carried out to elucidate the impact of these factors on RYGB outcomes.