Comparative analysis of linear- and circular-stapled gastrojejunostomies in Roux-en-Y gastric bypass: a focus on postoperative morbidity using the comprehensive complication index.

PURPOSE: The linear-stapled (LSA) and the circular-stapled anastomosis (CSA) are the two most commonly performed techniques for the gastrojejunostomy (GJ) during laparoscopic Roux-en-Y gastric bypass (RYGB). This study compared the outcome after both techniques with special focus on postoperative morbidity using the comprehensive complication index (CCI). METHODS: Five hundred eighty-eight patients operated between 01/2010 and 12/2019 were included in the final analysis and divided in two cohorts according to the surgical technique of the GJ (LSA (n = 290) or CSA (n = 298)). Before 09/2016, the CSA was exclusively performed for the GJ, while after 09/2016, the LSA was solely used. RESULTS: The mean CCI for patients with Clavien-Dindo complication grade ≥ 2 within the first 90 days after RYGB was 31 ± 9.1 in the CSA and 25.7 ± 6.8 in the LSA group (p < 0.001), both values still below the previously published benchmark cutoff (≤ 33.73). The C-reactive Protein (CRP)-levels on postoperative days (POD) 1 and 3 as well as the use of opioids on POD 1 were significantly higher in the CSA- than in the LSA-group (all p < 0.001). There were significantly more internal herniations in the CSA group during the first 24 postoperative months (p < 0.001). CONCLUSION: Patients after RYGB with CSA were found to have higher CCI values during the first 90 PODs compared to patients in which the LSA was applied. To achieve optimal outcomes in terms of patient morbidity, the LSA seems to be the superior technique for GJ in RYGB.

How best to combine liver transplantation and bariatric surgery?-Results from a global, web-based survey.

BACKGROUND AND AIMS: Obesity is a growing healthcare challenge worldwide and a significant risk factor for liver failure as seen with non-alcoholic steatohepatitis (NASH). Combining metabolic-bariatric surgery (MBS) with liver transplantation (LT) appears as attractive strategy to treat both, the underlying liver disease and obesity. However, there is an ongoing debate on best timing and patient selection. This survey was designed to explore the current treatment practice for patients with NASH and obesity worldwide. METHODS: A web-based survey was conducted in 2022 among bariatric and LT surgeons, and hepatologists from Europe, North and South America and Asia. RESULTS: The survey completion rate was 74% (145/196). The average respondents were 41-50 years (38%), male (82.1%) and had >20 years of clinical experience (42.1%). Centres with a high LT-caseload for NASH were mainly located in the USA and United Kingdom. Almost 30% have already performed a combination of LT with MBS and 49% plan to do it. A majority of bariatric surgeons prefer MBS before LT (77.2%), whereas most of LT surgeons (52%) would perform MBS during LT. Most respondents (n = 114; 80%) favour sleeve gastrectomy over other bariatric techniques. One third (n = 42; 29.4%) has an established protocol regarding MBS for LT candidates. CONCLUSION: The most experienced centres doing LT for NASH are in the USA and United Kingdom with growing awareness worldwide. Overall, a combination of MBS and LT has already been performed by a third of respondents. Sleeve gastrectomy is the bariatric technique of choice-preferably performed either before or during LT.

Standardized Assessment of Metabolic Bariatric Surgery Outcomes: Secondary Analysis of 2 Randomized Clinical Trials.

Importance: A standardized definition and reporting of metabolic bariatric surgery (MBS) outcomes is not available for actual clinical practice and science. Objective: To assess the feasibility of using a clinically relevant and feasible MBS outcome score (Swiss-Finnish Bariatric Metabolic Outcome Score [SF-BARI Score]). Design, Setting, and Participants: This assessment of a bariatric surgery outcome score is based on the secondary analysis of merged 5-year individual patient data (N = 457) of 2 large randomized clinical trials (Swiss SM-BOSS [Swiss Multicenter Bypass or Sleeve Study], conducted from January 2007 to November 2011, and Finnish SLEEVEPASS [Laparoscopic Gastric Bypass Vs Sleeve Gastrectomy to Treat Morbid Obesity], conducted from March 2008 until June 2010) that compared laparoscopic sleeve gastrectomy with laparoscopic Roux-en-Y gastric bypass in the treatment of severe obesity. This secondary analysis was performed from January 2022 to January 2023. Main Outcomes and Measures: The main outcome was the feasibility of the SF-BARI Score and the SF-BARI Score QOL (quality of life) as tools to assess MBS outcomes. The score includes percentage of total weight loss (%TWL), 4 obesity-related comorbidities (type 2 diabetes, hypertension, dyslipidemia, and obstructive sleep apnea), complications, and QOL, if available. Results: Among the 457 included patients, 323 (70.7%) were female and 134 (29.3%) were male, and the mean (SD) age was 45.6 (10.7) years. Outcomes for the SF-BARI Score were available for 435 patients (95.2%) at 1 year and 398 patients (87.1%) at 5 years and for SF-BARI Score QOL in 289 (63.2%) patients at 1 year and 318 patients (69.6%) at 5 years. The SF-BARI Score was correlated with both the SF-BARI Score QOL (r = 0.96; 95% CI, 0.95-0.96; P < .001) and %TWL (r = 0.86; 95% CI, 0.84-0.89; P < .001) and with the Bariatric Analysis and Reporting Outcome System (r = 0.59; 95% CI, 0.51-0.65; P < .001). Score outcomes were categorized as excellent, very good, good, fair, and suboptimal response. There was a statistically significant difference in scores at 1 vs 5 years (4.0; 95% CI, 1.4-6.6; P = .003), and the gastric bypass group had a higher score compared with the sleeve gastrectomy group (7.4; 95% CI, 3.4-11.5; P < .001). Conclusions and Relevance: These findings indicate that this metabolic bariatric surgery outcome score is a simple, relevant, and feasible composite tool to define and measure MBS outcomes, enabling standardized reporting. Trial Registration: ClinicalTrials.gov Identifiers: NCT00356213 (SM-BOSS) and NCT00793143 (SLEEVEPASS).

Global benchmarks in primary robotic bariatric surgery redefine quality standards for Roux-en-Y gastric bypass and sleeve gastrectomy.

BACKGROUND: Whether the benefits of the robotic platform in bariatric surgery translate into superior surgical outcomes remains unclear. The aim of this retrospective study was to establish the 'best possible' outcomes for robotic bariatric surgery and compare them with the established laparoscopic benchmarks. METHODS: Benchmark cut-offs were established for consecutive primary robotic bariatric surgery patients of 17 centres across four continents (13 expert centres and 4 learning phase centres) using the 75th percentile of the median outcome values until 90 days after surgery. The benchmark patients had no previous laparotomy, diabetes, sleep apnoea, cardiopathy, renal insufficiency, inflammatory bowel disease, immunosuppression, history of thromboembolic events, BMI greater than 50 kg/m2, or age greater than 65 years. RESULTS: A total of 9097 patients were included, who were mainly female (75.5%) and who had a mean(s.d.) age of 44.7(11.5) years and a mean(s.d.) baseline BMI of 44.6(7.7) kg/m2. In expert centres, 13.74% of the 3020 patients who underwent primary robotic Roux-en-Y gastric bypass and 5.9% of the 4078 patients who underwent primary robotic sleeve gastrectomy presented with greater than or equal to one complication within 90 postoperative days. No patient died and 1.1% of patients had adverse events related to the robotic platform. When compared with laparoscopic benchmarks, robotic Roux-en-Y gastric bypass had lower benchmark cut-offs for hospital stay, postoperative bleeding, and marginal ulceration, but the duration of the operation was 42 min longer. For most surgical outcomes, robotic sleeve gastrectomy outperformed laparoscopic sleeve gastrectomy with a comparable duration of the operation. In robotic learning phase centres, outcomes were within the established benchmarks only for low-risk robotic Roux-en-Y gastric bypass. CONCLUSION: The newly established benchmarks suggest that robotic bariatric surgery may enhance surgical safety compared with laparoscopic bariatric surgery; however, the duration of the operation for robotic Roux-en-Y gastric bypass is longer.

Assessing daily energy intake in adult women: validity of a food-recognition mobile application compared to doubly labelled water.

Accurate dietary assessment is crucial for nutrition and health research. Traditional methods, such as food records, food frequency questionnaires, and 24-hour dietary recalls (24HR), have limitations, such as the need for trained interviewers, time-consuming procedures, and inaccuracies in estimations. Novel technologies, such as image-based dietary assessment apps, have been developed to overcome these limitations. SNAQ is a novel image-based food-recognition app which, based on computer vision, assesses food type and volume, and provides nutritional information about dietary intake. This cross-sectional observational study aimed to investigate the validity of SNAQ as a dietary assessment tool for measuring energy and macronutrient intake in adult women with normal body weight (n = 30), compared to doubly labeled water (DLW), a reference method for total daily energy expenditure (TDEE). Energy intake was also estimated using a one-day 24HR for direct comparison. Bland-Altman plots, paired difference tests, and Pearson's correlation coefficient were used to assess agreement and relationships between the methods. SNAQ showed a slightly higher agreement (bias = -329.6 kcal/day) with DLW for total daily energy intake (TDEI) compared to 24HR (bias = -543.0 kcal/day). While both SNAQ and 24HR tended to underestimate TDEI, only 24HR significantly differed from DLW in this regard (p < 0.001). There was no significant relationship between estimated TDEI and TDEE using SNAQ (R2 = 27%, p = 0.50) or 24HR (R2 = 34%, p = 0.20) and there were no significant differences in energy and macronutrient intake estimates between SNAQ and 24HR (Δ = 213.4 kcal/day). In conclusion, these results indicate that SNAQ provides a closer representation of energy intake in adult women with normal body weight than 24HR when compared to DLW, but no relationship was found between the energy estimates of DLW and of the two dietary assessment tools. Further research is needed to determine the clinical relevance and support the implementation of SNAQ in research and clinical settings. Clinical trial registration: This study is registered on ClinicalTrials.gov with the unique identifier NCT04600596 (https://clinicaltrials.gov/ct2/show/NCT04600596).

The 'Behavioral Balance Model': A new perspective on the aetiology and therapy of obesity.

Obesity is a debilitating disease of global proportions that necessitates refined, concept-driven therapeutic approaches. Policy makers, the public and even health care professionals, but also individuals with obesity harbour many misconceptions regarding this disease, which leads to prejudice, negative attitudes, stigmatization, discrimination, self-blame, and failure to provide and finance adequate medical care. Decades of intensive, successful scientific research on obesity have only had a very limited effect on this predicament. We propose a science-based, easy-to-understand conceptual model that synthesizes the complex pathogenesis of obesity including biological, psychological, social, economic and environmental aspects with the aim to explain and communicate better the nature of obesity and currently available therapeutic modalities. According to our integrative 'Behavioral Balance Model', 'top-down cognitive control' strategies are implemented (often with limited success) to counterbalance the increased 'bottom-up drive' to gain weight, which is triggered by biological, psycho-social and environmental mechanisms in people with obesity. Besides offering a deeper understanding of obesity, the model also highlights why there is a strong need for multimodal therapeutic approaches that may not only increase top-down control but also reduce a pathologically increased bottom-up drive.

Attitudes of primary care physicians toward bariatric surgery: a free word association networks analysis.

BACKGROUND: Primary care physicians (PCPs) hold major responsibility in referring patients with obesity eligible for bariatric surgery (BS). OBJECTIVE: The aim was to explore PCPs' mental representation of BS in order to identify barriers and catalysts of BS referral practices. SETTING: Switzerland. METHODS: A total of 3526 PCPs were invited to participate in an online survey. PCPs were asked to write the first 5 words that came to their mind about the term "bariatric surgery." Additionally, they had to pick 2 emotions that best described each provided association. Demographic data and obesity-related referral patterns were collected. Mental representation network was constructed based on co-occurrence of associations, using validated data-driven methodology. RESULTS: In all, 216 PCPs completed the study (response rate: 6.13%). Respondents were aged 55 ± 9.8 years, had an equal sex distribution, and practiced mainly in urban settings. Three mental representations of BS emerged: indication-focused (most frequent associations: "obesity," "diabetes"), treatment-focused ("gastric bypass," "weight loss"), and outcome-focused ("complications," "challenging follow-up"). The emotional label "interested" was used significantly more frequently in the treatment-focused group. Comparison of PCPs among mental modules showed that those with a treatment-focused mindset referred patients for BS most frequently and were significantly more willing to follow up with postbariatric patients (χ2 = 17.8, P = .022). CONCLUSIONS: PCPs think about BS along 3 mental representations, and the treatment-focused attitude was coupled with the highest willingness to refer eligible patients for BS. Confidence in performing postbariatric follow-up was identified as catalyst of BS referral. Access to optimal care for patients with obesity may be improved accordingly.

Prospective clinical cohort study: low incidence of Barrett esophagus but high rate of reflux disease at 5-year follow-up after sleeve gastrectomy versus Roux-en-Y gastric bypass.

BACKGROUND: Gastroesophageal reflux disease seems more frequent after laparoscopic sleeve gastrectomy (LSG) than Roux-en-Y gastric bypass (LRYGB). Retrospective case series have raised concerns about a high incidence of Barrett esophagus (BE) after LSG. OBJECTIVE: This prospective clinical cohort study compared the incidence of BE ≥5 years after LSG and LRYGB. SETTING: St. Clara Hospital, Basel, and University Hospital, Zürich, Switzerland. METHODS: Patients were recruited from 2 bariatric centers where preoperative gastroscopy is standard practice and LRYGB is preferred for patients with preexisting gastroesophageal reflux disease. At follow-up ≥5 years after surgery, patients underwent gastroscopy with quadrantic biopsies from the squamocolumnar junction and metaplastic segment. Symptoms were assessed using validated questionnaires. Wireless pH measurement assessed esophageal acid exposure. RESULTS: A total of 169 patients were included, with a median 7.0 ± 1.5 years after surgery. In the LSG group (n = 83), 3 patients had endoscopically and histologically confirmed de novo BE; in the LRYGB group (n = 86), there were 2 patients with BE, 1 de novo and 1 preexisting (de novo BE, 3.6% versus 1.2%; P = .362). At follow-up, reflux symptoms were reported more frequently by the LSG group than by the LRYGB group (51.9% versus 10.5%). Similarly, moderate-to-severe reflux esophagitis (Los Angeles grade B-D) was more common (27.7% versus 5.8%) despite greater use of proton pump inhibitors (49.4% versus 19.7%), and pathologic acid exposure was more frequent in patients who underwent LSG than in patients who underwent LRYGB. CONCLUSIONS: After at least 5 years of follow-up, a higher incidence of reflux symptoms, reflux esophagitis, and pathologic esophageal acid exposure was found in patients who underwent LSG compared with patients who underwent LRYGB. However, the incidence of BE after LSG was low and not significantly different between the 2 groups.

The Effect of a Multifaceted Intervention Including Classroom Education and Bariatric Weight Suit Use on Medical Students' Attitudes toward Patients with Obesity.

INTRODUCTION: Weight bias refers to negative attitudes toward individuals because of their weight. Evidence-based strategies to successfully reduce weight bias in medical students are lacking. The purpose of this study was to investigate the impact of a multifaceted intervention on medical students' attitudes toward patients with obesity. METHODS: Third and fourth year medical students (n = 79), who enrolled in an 8-week graduate course focusing on the various epidemiologic, physiological, and clinical aspects of obesity, including a gamification task with bariatric weight suits (BWSs), were asked to complete the Nutrition, Exercise and Weight Management (NEW) Attitudes Scale questionnaire pre- and post-course. The inclusion period was between September 2018 and June 2021 and covered 4 consecutive groups of students. RESULTS: The overall NEW Attitudes Scale scores did not change significantly pre- versus post-intervention (pre-course: 19.59, post-course: 24.21, p value = 0.24). However, the subgroup of 4th year medical students showed a significant improvement in their attitudes (pre-course: 16.4, post-course: 26.16, p value = 0.02). The Thurstone rating of 9 out of 31 individual survey items changed significantly from pre- to post-course with a moderate strength (Cramer's V >0.2), including 5 items showing weight bias reduction. The disagreement with the statement "overweight/obese individuals lack willpower" increased from 37 to 68%. CONCLUSION: These findings suggest that in medical students with a low level of weight bias at baseline, a semester course on obesity combined with BWS use affects only a limited number of items of the NEW Attitudes Scale questionnaire. The sensitization of medical students to weight stigma has the potential to improve quality of healthcare for patients with obesity.

There is no evidence that carbon dioxide-enriched oxygen before apnea affects the time to arterial desaturation, but it might improve cerebral oxygenation in anesthetized obese patients: a single-blinded randomized crossover trial.

PURPOSE: Carbon dioxide (CO2) increases cerebral perfusion. The effect of CO2 on apnea tolerance, such as after anesthesia induction, is unknown. This study aimed to assess if cerebral apnea tolerance can be improved in obese patients under general anesthesia when comparing O2/Air (95%O2) to O2/CO2 (95%O2/5%CO2). METHODS: In this single-center, single-blinded, randomized crossover trial, 30 patients 18-65 years, with body mass index > 35 kg/m2, requiring general anesthesia for bariatric surgery, underwent two apneas that were preceded by ventilation with either O2/Air or O2/CO2 in random order. After anesthesia induction, intubation, and ventilation with O2/Air or O2/CO2 for 10 min, apnea was performed until the cerebral tissue oxygenation index (TOI) dropped by a relative 20% from baseline (primary endpoint) or oxygen saturation (SpO2) reached 80% (safety abortion criterion). The intervention was then repeated with the second substance. RESULTS: The safety criterion was reached in all patients before cerebral TOI decreased by 20%. The time until SpO2 dropped to 80% was similar in the two groups (+ 6 s with O2/CO2, 95%CI -7 to 19 s, p = 0.37). Cerebral TOI and PaO2 were higher after O2/CO2 (+ 1.5%; 95%CI: from 0.3 to 2.6; p = 0.02 and + 0.6 kPa; 95%CI: 0.1 to 1.1; p = 0.02). CONCLUSION: O2/CO2 improves cerebral TOI and PaO2 in anesthetized bariatric patients. Better apnea tolerance could not be confirmed.

Post-bariatric changes in ingestive behavior: Shift in macronutrient preferences in rats and dynamic adaptation of the within-meal microstructure in humans.

This invited review is based on a presentation given at the Annual Meeting of the Society for the Study of Ingestive Behavior in July 2022 and provides the summary of two recent studies on changes in ingestive behavior following bariatric surgery (BS). First, long-term changes in daily absolute and relative macronutrient intake are reported in a rodent model of Roux-en-Y gastric bypass (RYGB). Rats undergoing RYGB progressively decreased their daily calorie- and daily fat intake compared to their preoperative baseline and to the intake of sham operated animals. Second, postbariatric changes in the within-meal ingestive microstructure are portrayed, based on longitudinal data collected in RYGB patients using a drinkometer. The post-RYGB meal size showed a dynamic adjustment process, with the highest decrease in the early postoperative phase, followed by a steady convalescence up to 1-year, at which point the meal size of RYGB patients became comparable to the normal weight adults'. Results are contextualized and contrasted to recent reports on the effect of BS on taste and food choices and consumption. The showcased evidence supports the role of ingestive adaptation and learning in the achievement of reduced calorie intake after RYGB, both in humans and in rodents. The reorganized upper-gastrointestinal anatomy supposedly leads to increased postingestive caloric sensibility, which might be an important behavioral mediator of decreased postbariatric meal size and consequent weight loss.

Validation of the individualized metabolic surgery score for bariatric procedure selection in the merged data of two randomized clinical trials (SLEEVEPASS and SM-BOSS).

BACKGROUND: LSG and LRYGB are globally the most common bariatric procedures. IMS score categorizes T2D severity (mild, moderate, and severe) based on 4 independent preoperative predictors of long-term remission as follows: T2D duration, number of diabetes medications, insulin use, and glycemic control. IMS score has not been validated in a randomized patient cohort. OBJECTIVES: To assess the feasibility of individualized metabolic surgery (IMS) score in facilitating procedure selection between laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) for patients with severe obesity and type 2 diabetes (T2D). SETTING: Merged individual patient-level 5-year data of 2 large randomized clinical trials (SLEEVEPASS and SM-BOSS [Swiss Multicenter Bypass or Sleeve Study]). METHODS: IMS score was calculated for study patients and its performance was analyzed. RESULTS: One hundred thirty-nine out of 155 patients with T2D had available preoperative data to calculate IMS score as follows: mild stage (n = 41/139), moderate stage (n = 77/139), severe stage (n = 21/139). At 5 years, 135 (87.1%, 67 LSG/68 LRYGB) were available for follow-up and 121 patients had both pre- and postoperative data. Diabetes remission rates according to preoperative IMS score were as follows: mild stage 87.5% (n = 14/16) after LSG and 85.7% (n = 18/21) after LRYGB (P = .999), moderate stage 42.9% (n = 15/35) and 45.2% (n = 14/31) (P = .999), and severe stage 18.2% (n = 2/11) and 0% (n = 0/7) (P = .497), respectively. The T2D remission rate varied significantly between the stages as follows: mild versus moderate odds ratio (OR) 8.3 (95% CI, 2.8-24.0; P < .001), mild versus severe OR 52.2 (95% CI 9.0-302.3; P < .001), and moderate versus severe OR 6.3 (95% CI, 1.3-29.8; P = .020). CONCLUSIONS: In our study, remission rates of T2D were not statistically different after LSG and LRYGB among all patients and among patients with mild, moderate, and severe diabetes stratified by the IMS score. However, the study may be underpowered to detect differences due to small number of patients in each subgroup. IMS score seemed to be useful in predicting long-term T2D remission after bariatric surgery.

Sustained weight loss after duodenal-jejunal bypass liner treatment in patients with body mass index below, but not above 35 kg/m2 : A retrospective cohort study.

Previous data from short term studies have shown an efficacy of the duodenal-jejunal bypass liner (DJBL) for weight loss. However, less data is available regarding weight change after device removal and possible predictors for weight loss. This is a retrospective chart review of all patients who had DJBL inserted at the University Hospital Zurich between December 2012 and June 2015. A total of 27 patients had DJBL insertion. The median BMI at baseline was 38.5 (34.0-42.2) kg/m2 . In the 24 patients with DJBL treatment >3 months (failed implantation or early removal due to side effects in 3 patients), the mean duration of implantation was 42.9 ± 13.1 weeks. During the treatment, the mean total body weight loss (%TBWL) was 15.0 ± 8.3%. Fifteen patients had long-term follow-up data available (mean duration of follow-up 4.0 ± 0.9 years). The mean weight change was 12.7 ± 12.8 kg, corresponding with a mean % weight regain of 13.3 ± 13.3%. Five patients (33.3%) subsequently underwent bariatric surgery. In patients with class I obesity (BMI <35 kg/m2 at baseline), 4 out of 6 (66.7%) had a stable weight or only a weight regain <7%. In contrast, no patient with BMI >35 kg/m2 at baseline was able to keep weight regain below 7%. DJBL is an effective treatment for obesity, but substantial weight regain occurs during long-term follow up after the device removal, in particular in patients with BMI > 35 kg/m2 .

The role of bariatric and metabolic surgery in the development, diagnosis, and treatment of endometrial cancer.

The obesity pandemic continues to contribute to a worsening burden of disease worldwide. The link between obesity and diseases such as diabetes, cardiovascular disease, and cancer has been well established, yet most patients living with obesity remain untreated or undertreated. Metabolic and bariatric surgery is the most effective and durable treatment for obesity, is safe, and may have a protective benefit with respect to cancer incidence. In this review, an overview of the link between obesity, metabolic surgery, and cancer is discussed with emphasis on indications for endometrial cancer, the malignancy most strongly associated with obesity. Considerable evidence from retrospective and prospective cohort studies supports a decreased risk of endometrial cancer in patients with obesity who undergo bariatric surgery compared with nonsurgical controls. Survivors of endometrial cancer are at increased risk of poor health outcomes associated with obesity, and women with endometrial cancer are more likely to die of cardiovascular disease and other obesity-related illnesses than of the malignancy itself. Recent advances in anticancer drug therapies have targeted pathways that may also be therapeutically altered with metabolic surgery. Metabolic surgery has significant potential to enter the treatment paradigm for endometrial cancer, and gynecologic oncologist visits present an opportunity to identify patients who may benefit the most.

Burst-pause criterion derivation for drinkometer measurements of ingestive behavior.

The drinkometer is a promising device for the study of ingestive behavior of liquid meals in humans. It can be used to investigate behavior in different target populations. However, ingestive behavior has a great variability across study participants. Therefore, a new analytical approach is required for the extraction and analysis of drinkometer-derived data that could account for this variability. We developed an optimized protocol to predict an optimal burst-pause criterion (PC) for the extraction of PC-dependent microstructural parameters of ingestive behavior. These describe the microstructure of bursts, while PC-independent parameters describe the microstructure of sucks. Therefore, a PC is required to analyze separately two physiologically different parts of behavior. To accomplish this burst-pause criterion derivation (BPCD), a Gaussian Mixture Model (GMM) was built for estimation of two probability density functions (PDFs). These model the distribution of inter-suck intervals (ISIs) and inter-burst intervals (IBIs), respectively. The PC is defined at the intersection point of the two density functions. A Kaplan-Meier (KM) survival analysis was performed for post-hoc verification of the fit of the predicted optimal PC to the ISI distribution. In this protocol paper, we present a walkthrough of the data analysis of drinkometer-derived data for the measurement of microstructure of ingestive behavior based on previous results published by our group [1].•Standardization of the burst-pause criterion derivation for drinkometer measurements of ingestive behavior.•All codes are publicly available in a repository.•The method can be easily adapted to studies with larger sample size or more than one study stimulus.

Effects of acute administration of trimethylamine N-oxide on endothelial function: a translational study.

Elevated circulating levels of nutrient-derived trimethylamine N-oxide (TMAO) have been associated with the onset and progression of cardiovascular disease by promoting athero-thrombosis. However, in conditions like bariatric surgery (Roux-en-Y gastric bypass, RYGB), stable increases of plasma TMAO are associated with improved endothelial function and reduced cardiovascular morbidity and mortality, thus questioning whether a mechanistic relationship between TMAO and endothelial dysfunction exists. Herein, we translationally assessed the effects of acute TMAO exposure on endothelial dysfunction, thrombosis and stroke. After RYGB, fasting circulating levels of TMAO increased in patients and obese rats, in parallel with an improved gluco-lipid profile and higher circulating bile acids. The latter enhanced FXR-dependent signalling in rat livers, which may lead to higher TMAO synthesis post RYGB. In lean rats, acute TMAO injection (7 mg kg-1) 1.5-h before sacrifice and ex-vivo 30-min incubation of thoracic aortas with 10-6 M TMAO did not impair vasodilation in response to acetylcholine (Ach), glucagon-like peptide 1, or insulin. Similarly, in lean WT mice (n = 5-6), TMAO injection prior to subjecting mice to ischemic stroke or arterial thrombosis did not increase its severity compared to vehicle treated mice. Endothelial nitric oxide synthase (eNOS) activity and intracellular stress-activated pathways remained unaltered in aorta of TMAO-injected rats, as assessed by Western Blot. Pre-incubation of human aortic endothelial cells with TMAO (10-6 M) did not alter NO release in response to Ach. Our results indicate that increased plasmatic TMAO in the near-physiological range seems to be a neutral bystander to vascular function as translationally seen in patients after bariatric surgery or in healthy lean rodent models and in endothelial cells exposed acutely to TMAO.

Results of robotic TAPP and conventional laparoscopic TAPP in an outpatient setting: a cohort study in Switzerland.

PURPOSE: Recently, robotic surgery has been increasingly performed in hernia surgery. Although feasibility and safety of robot-assisted inguinal hernia repair in an inpatient setting have been already shown, its role in outpatient hernia surgery has not yet been investigated. Thus, this study aimed to compare robot-assisted TAPP (r-TAPP) and conventional laparoscopic TAPP (l-TAPP) in an outpatient setting. METHODS: A prospective database of patients with inguinal hernia treated by l-TAPP or r-TAPP in an outpatient setting during a 1-year period was analyzed in a comparative cohort study. All patients underwent a check-up appointment with their surgeon within 3 days and 6 weeks postoperatively. Data on surgical time, perioperative complications, and postoperative pain were collected. Pain was recorded by using a Verbal Rating Scale (VRS). RESULTS: Overall, outpatient laparoendoscopic inguinal hernia repair was performed in 58 patients (29 l-TAPP; 29 r-TAPP). Mean age was 57 years (21-81), mean BMI 24.5 kg/m2 (19-33) with no differences between both groups. Most patients reported none or only a low postoperative pain level in both groups (89.6% in l-TAPP group; 100% in r-TAPP), while there was a trend for less pain after r-TAPP. In both groups, there was one case of postoperative hematoma, which was successfully treated by conservative means. No other complications occurred during follow-up in either group and there was no 30-day-readmission, no unplanned overstay or any 30-day mortality in the cohort. CONCLUSION: Robot-assisted inguinal hernia surgery can be safely performed in an outpatient setting with a tendency to less pain when compared to the conventional laparoscopic technique. Cost-effectiveness and cost-coverage of outpatient robot-assisted inguinal hernia surgery must be further investigated in times of limited health cost resources and diagnosis-related medical reimbursements.

Early Postoperative Exposure to High-Fat Diet Does Not Increase Long-Term Weight Loss or Fat Avoidance After Roux-en-Y Gastric Bypass in Rats.

Background: Bariatric surgery alters food preferences in rats and reportedly decreases desire to consume high-fat high-sugar food in humans. The aim of this study was to investigate whether early post-operative exposure to high-fat food could increase body weight loss after Roux-en-Y gastric bypass (RYGB) by triggering fat avoidance. Methods: Male Wistar rats underwent either RYGB (n = 15) or sham-operations (n = 16). Preoperatively a standardized 4-choice cafeteria diet [dietary options: low-fat/low-sugar (LFLS), low-fat/high-sugar (LFHS), high-fat/low-sugar (HFLS), high-fat/high-sugar (HFHS)] was offered. First, each option was available for 4 days, thereafter rats were offered the 4 options simultaneously for 3 days preoperatively. Post-surgery, 8 rats in the RYGB- and 8 in the sham-group were exposed to a high-fat content diet (Oatmeal + 30% lard, OM+L) for 10 days, while 7 RYGB rats and 8 sham-rats received OM alone. From the 11th postoperative day, the 4-choice cafeteria diet was reintroduced for 55-days. The intake of all available food items, macronutrients and body weight changes were monitored over 8 weeks. Main outcomes were long-term body-weight and daily change in relative caloric intake during the postoperative cafeteria period compared to the preoperative cafeteria. Results: During the first 12 days of postoperative cafeteria access, RYGB-rats exposed to OM+L had a higher mean caloric intake per day than RYGB rats exposed to OM alone (Δ10 kCal, P adj = 0.004), but this difference between the RYGB groups disappeared thereafter. Consequently, in the last 33 days of the postoperative cafeteria diet, the mean body weight of the RYGB+OM+L group was higher compared to RYGB+OM (Δ51 g, P adj < 0.001). RYGB rats, independently from the nutritional intervention, presented a progressive decrease in daily consumption of calories from fat and increased their daily energy intake mainly from non-sugar carbohydrates. No such differences were detected in sham-operated controls exposed to low- or high fat postoperative interventions. Conclusion: A progressive decrease in daily fat intake over time was observed after RYGB, independently from the nutritional intervention. This finding confirms that macronutrient preferences undergo progressive changes over time after RYGB and supports the role of ingestive adaptation and learning. Early postoperative exposure to high-fat food failed to accentuate fat avoidance and did not lead to superior weight loss in the long-term.

Two cases of an internal hernia after laparoscopic sigmoid resection.

Two patients with a laparoscopic resection of the sigmoid colon in their surgical history were diagnosed with an internal hernia because of a mesenteric gap underneath the descending neocolon. While the first case demonstrated a strongly symptomatic patient with a closed-loop obstruction of the small bowel, the second case was less obvious and correct diagnosis was achieved after a few weeks by finally performing a diagnostic laparoscopy. Since internal hernias after laparoscopic sigmoid resection are a rare complication and as presented in the second case can display very unspecific symptoms, the surgeon's awareness is not immediately raised towards it. Therefore, an asymptomatic internal hernia bears a constant risk of a life-threatening outcome allowing to recommend an initial closure of the mesenteric gap. In both cases, successful treatment was achieved by surgery and intraoperatively closing the remaining mesenteric gap. Subsequently recovery and follow-up were uneventful.

Association between microstructure of ingestive behavior and body weight loss in patients one year after Roux-en-Y gastric bypass.

Roux-en-Y gastric bypass (RYGB) is one of the most effective procedures in the treatment of obesity. However, the predictive value of the microstructure of ingestion has not been widely investigated in this context. Here, we applied a recently developed drinkometer device to analyze the microstructure of ingestive behavior during a liquid meal in women and investigate whether it correlated with measures of weight loss after RYGB. Macro- and microstructural parameters of ingestive behavior of female patients (n = 24) one year after RYGB were measured in two different test sessions within a period of two weeks using the drinkometer. A Pearson correlation analysis was performed to compare the macro- and microstructural parameters of ingestive behavior with the percentage of total weight loss (%TWL), percentage excess BMI loss (%EBMIL), and body mass index (BMI) one year after RYGB, as well as age. A Bonferroni adjusted p < 0.003 was considered significant for the correlation analysis. For all other statistical tests, a p < 0.05 was considered significant. One year after surgery, a significant body weight loss was achieved in our study population (111.2 ± 15.6 kg vs 73.4 ± 11.7 kg; ***p < 0.001), with a mean%TWL of 33.8% (range: 20.4-48.6%). At the first test session,%TWL correlated with suck duration (r = 0.41, 0.05 > p > 0.003);%EBMIL correlated with both suck duration (r = 0.64, *p < 0.003) and inter-suck intervals (ISIs, r = -0.47, *p < 0.003), and, finally, BMI correlated with suck duration (r = 0.62, *p < 0.003) and ISIs (r = 0.48, *p < 0.003). However, at the second test session, no correlation was found between the body weight loss and the recorded ingestive parameters. Furthermore, no statistically significant difference was found in microstructural parameters of ingestive behavior between the two test sessions even though meal size decreased by 20% on the second visit (342.6.6 ± 167 kcal vs. 271.8 ± 142.8 kcal). A greater body weight loss of patients one year after surgery seems to be associated with longer suck duration and shorter ISIs, but only when the stimulus is tested for the first time by the study participants. This study contributes to the current knowledge about the ingestive behavior of bariatric patients one year after RYGB in terms of its association with the achieved weight loss. The use of the drinkometer device for the measurement of microstructure of ingestive behavior should be further expanded to different research questions and patient subgroups other than good responders. Its possible applications in clinical and behavioral research need to be included in the agenda of bariatric research.