What Is Weight Loss After Bariatric Surgery Expressed in Percentage Total Weight Loss (%TWL)? A Systematic Review

Percentage total weight loss (%TWL) might be better than percentage excess weight loss to express weight loss in bariatric surgery. In this systematic review, performed according to the PRISMA statement, results of laparoscopic sleeve gastrectomy (LSG) and Roux-en-Y gastric bypass (LRYGB) are assessed in %TWL. A total of 13,426 studies were screened and 49 included, reporting data of 24,760 patients. The results show that, despite limiting data, LRYGB is favorable over LSG in terms of weight loss in short-term follow-up. Although recent guidelines recommend to use %TWL when reporting outcome in bariatric surgery, this study shows that there is still insufficient quality data in %TWL, especially on LSG. The use of %TWL as the primary outcome measure in bariatric surgery should be encouraged. Graphical abstract: [Figure not available: see fulltext.]

Fluorescent Imaging with Indocyanine Green during Laparoscopic Cholecystectomy in Patients at Increased Risk of Bile Duct Injury

Background. Although rare, injury to the common bile duct (CBD) during laparoscopic cholecystectomy (LC) can be reduced by better intraoperative visualization of the cystic duct (CD) and CBD. The aim of this study was to establish the efficacy of early visualization of the CD and the added value of CBD identification, using near-infrared (NIR) light and the fluorescent agent indocyanine green (ICG), in patients at increased risk of bile duct injury. Materials and Methods. Patients diagnosed with complicated cholecystitis and scheduled for LC were included. The CBD and CD were visualized with NIR light before and during dissection of the liver hilus and at critical view of safety (CVS). Results. Of the 20 patients originally included, 2 were later excluded due to conversion. In 6 of 18 patients, the CD was visualized early during dissection and prior to imaging with conventional white light. The CBD was additionally visualized with ICG-NIR in 7 of 18 patients. In 1 patient, conversion was prevented due to detection of the CD and CBD with ICG-NIR. Conclusions. Early visualization of the CD or additional identification of the CBD using ICG-NIR in patients with complicated cholecystolithiasis can be helpful in preventing CBD injury. Future studies should attempt to establish the optimal dosage and time frame for ICG administration and bile duct visualization with respect to different gallbladder pathologies

Can a laparoscopic Roux-en-Y gastric bypass be safely performed by surgical residents in a bariatric center-of-excellence? The learning curve of surgical residents in bariatric surgery

Background A learning curve (LC) is a graphic display of the number of consecutive procedures performed necessary to reach competence and is defined by complications and duration of surgery (DOS). There is little evidence on the LC of surgical residents in bariatric surgery. Aim of the study is to evaluate whether the laparoscopic Roux-en-Y gastric bypass (LRYGB) can be safely performed by surgical residents, to evaluate the LC of surgical residents for LRYGB and to assess whether surgical residents fit in the LC of the bariatric center which has been established by their proctors. Methods Records of all 3389 consecutive primary LRYGB patients, operated between December 2007 and January 2016 in a bariatric center-of-excellence in Amsterdam, were reviewed. Differences in DOS were assessed by means of a linear regression model. Differences in complications (classified as Clavien-Dindo >= 2) were evaluated with the chi(2) or the Fisher exact test. Cases were clustered in groups of 70 for comparison and reported for residents with >= 70 cases as primary surgeon. Results Four surgeons (S1-4) and three residents (R1-3) performed 2690 (88.2%) and 361 (11.8%) of 3051 LRYGBs, respectively. Median (IQR) DOS was 52.0 (42.0-65.0) min for S1-4 versus 53.0 (46.0-63.0) min for R1-3 (p = 0.52). The LC of R1-3 in their first 70 cases (n = 210) differs significantly from the individual (n = 70) LCs of surgeon 1, 2, and 3, with remarkably shorter DOS for the residents (adjusted p <0.0001; p <0.001 and p = 0.0002, respectively) and the same amount of surgical complications 5.1% (137/2690) for S1-4 versus 3.0% (11/361) for R1-3 (p = 0.089). Conclusion Laparoscopic Roux-en-Y gastric bypass can be safely performed by surgical residents under supervision of experienced bariatric surgeons. Surgical residents benefit from the experience of their proctors and they fit faultlessly in the LC of the surgical team, as set out by their proctors in a large bariatric center-of-excellenc

Distribution of lymph node metastases in esophageal adenocarcinoma after neoadjuvant chemoradiation therapy: a prospective study

Background: The distribution of lymph node metastases in esophageal adenocarcinoma following neoadjuvant chemoradiation (nCRTx) is unclear, but may have consequences for radiotherapy and surgery. The aim of this study was to define the distribution of lymph node metastases and relation to the radiation field in patients following nCRTx and esophagectomy. Methods: Between April 2014 and August 2015 esophageal adenocarcinoma patients undergoing transthoracic esophagectomy with 2-field lymphadenectomy following nCRTx were included in this prospective observational study. Lymph node stations according to AJCC 7 were separately investigated. The location of lymph node metastases in relation to the radiation field was determined. The primary endpoint was the distribution of lymph node metastases and relation to the radiation field, the secondary endpoints were high-risk stations and risk factors for lymph node metastases and relation to survival. Results: Fifty consecutive patients were included. Lymph node metastases were found in 60% of patients and most frequently observed in paraesophageal (28%), left gastric artery (24%), and celiac trunk (18%) stations. Fifty-two percent had lymph node metastases within the radiation field. The incidence of lymph node metastases correlated significantly with ypT-stage (p = 0.002), cT-stage (p = 0.005), lymph angioinvasion (p = 0.004), and Mandard (p = 0.002). The number of lymph node metastases was associated with survival in univariable analysis (HR 1.12, 95% CI 1.068–1.173, p < 0.001). Conclusions: Esophageal adenocarcinoma frequently metastasizes to both the mediastinal and abdominal lymph node stations. In this study, more than half of the patients had lymph node metastases within the radiation field. nCRTx is therefore not a reason to minimize lymphadenectomy in patients with esophageal adenocarcinoma

Differences in systemic and mucosal SARS-CoV-2 antibody prevalence in a prospective cohort of Dutch children

Background: As SARS-CoV-2 will likely continue to circulate, low-impact methods become more relevant to monitor antibody-mediated immunity. Saliva sampling could provide a non-invasive method with reduced impact on children. Studies reporting on the differences between systemic and mucosal humoral immunity to SARS-CoV-2 are inconsistent in adults and scarce in children. These differences may be further unraveled by exploring associations to demographic and clinical variables. Methods: To evaluate the use of saliva antibody assays, we performed a cross-sectional cohort study by collecting serum and saliva of 223 children attending medical services in the Netherlands (irrespective of SARS-CoV-2 exposure, symptoms or vaccination) from May to October 2021. With a Luminex and a Wantai assay, we measured prevalence of SARS-CoV-2 spike (S), receptor binding domain (RBD) and nucleocapsid-specific IgG and IgA in serum and saliva and explored associations with demographic variables. Findings: The S-specific IgG prevalence was higher in serum 39% (95% CI 32 – 45%) than in saliva 30% (95% CI 24 – 36%) (P ≤ 0.003). Twenty-seven percent (55/205) of children were S-specific IgG positive in serum and saliva, 12% (25/205) were only positive in serum and 3% (6/205) only in saliva. Vaccinated children showed a higher concordance between serum and saliva than infected children. Odds for saliva S-specific IgG positivity were higher in girls compared to boys (aOR 2.63, P = 0.012). Moreover, immunocompromised children showed lower odds for S- and RBD-specific IgG in both serum and saliva compared to healthy children (aOR 0.23 – 0.25, P ≤ 0.050). Conclusions: We showed that saliva-based antibody assays can be useful for identifying SARS-CoV-2 humoral immunity in a non-invasive manner, and that IgG prevalence may be affected by sex and immunocompromisation. Differences between infection and vaccination, between sexes and between immunocompromised and healthy children should be further investigated and considered when choosing systemic or mucosal antibody measurement

Self-organized metabotyping of obese individuals identifies clusters responding differently to bariatric surgery

Weight loss through bariatric surgery is efficient for treatment or prevention of obesity related diseases such as type 2 diabetes and cardiovascular disease. Long term weight loss response does, however, vary among patients undergoing surgery. Thus, it is difficult to identify predictive markers while most obese individuals have one or more comorbidities. To overcome such challenges, an in-depth multiple omics analyses including fasting peripheral plasma metabolome, fecal metagenome as well as liver, jejunum, and adipose tissue transcriptome were performed for 106 individuals undergoing bariatric surgery. Machine leaning was applied to explore the metabolic differences in individuals and evaluate if metabolism-based patients' stratification is related to their weight loss responses to bariatric surgery. Using Self-Organizing Maps (SOMs) to analyze the plasma metabolome, we identified five distinct metabotypes, which were differentially enriched for KEGG pathways related to immune functions, fatty acid metabolism, protein-signaling, and obesity pathogenesis. The gut metagenome of the most heavily medicated metabotypes, treated simultaneously for multiple cardiometabolic comorbidities, was significantly enriched in Prevotella and Lactobacillus species. This unbiased stratification into SOM-defined metabotypes identified signatures for each metabolic phenotype and we found that the different metabotypes respond differently to bariatric surgery in terms of weight loss after 12 months. An integrative framework that utilizes SOMs and omics integration was developed for stratifying a heterogeneous bariatric surgery cohort. The multiple omics datasets described in this study reveal that the metabotypes are characterized by a concrete metabolic status and different responses in weight loss and adipose tissue reduction over time. Our study thus opens a path to enable patient stratification and hereby allow for improved clinical treatments

Perioperative management of obstructive sleep apnea in bariatric surgery: a consensus guideline

BACKGROUND: The frequency of metabolic and bariatric surgery (MBS) is increasing worldwide, with over 500,000 cases performed every year. Obstructive sleep apnea (OSA) is present in 35%-94% of MBS patients. Nevertheless, consensus regarding the perioperative management of OSA in MBS patients is not established. OBJECTIVES: To provide consensus based guidelines utilizing current literature and, when in the absence of supporting clinical data, expert opinion by organizing a consensus meeting of experts from relevant specialties. SETTING: The meeting was held in Amsterdam, the Netherlands. METHODS: A panel of 15 international experts identified 75 questions covering preoperative screening, treatment, postoperative monitoring, anesthetic care and follow-up. Six researchers reviewed the literature systematically. During this meeting, the "Amsterdam Delphi Method" was utilized including controlled acquisition of feedback, aggregation of responses and iteration. RESULTS: Recommendations or statements were provided for 58 questions. In the judgment of the experts, 17 questions provided no additional useful information and it was agreed to exclude them. With the exception of 3 recommendations (64%, 66%, and 66% respectively), consensus (>70%) was reached for 55 statements and recommendations. Several highlights: polysomnography is the gold standard for diagnosing OSA; continuous positive airway pressure is recommended for all patients with moderate and severe OSA; OSA patients should be continuously monitored with pulse oximetry in the early postoperative period; perioperative usage of sedatives and opioids should be minimized. CONCLUSION: This first international expert meeting provided 58 statements and recommendations for a clinical consensus guideline regarding the perioperative management of OSA patients undergoing MBS.status: publishe

Perioperative management of obstructive sleep apnea in bariatric surgery : a consensus guideline

Background: The frequency of metabolic and bariatric surgery (MBS) is increasing worldwide, with over 500,000 cases performed every year. Obstructive sleep apnea (OSA) is present in 35%–94% of MBS patients. Nevertheless, consensus regarding the perioperative management of OSA in MBS patients is not established. Objectives: To provide consensus based guidelines utilizing current literature and, when in the absence of supporting clinical data, expert opinion by organizing a consensus meeting of experts from relevant specialties. Setting: The meeting was held in Amsterdam, the Netherlands. Methods: A panel of 15 international experts identified 75 questions covering preoperative screening, treatment, postoperative monitoring, anesthetic care and follow-up. Six researchers reviewed the literature systematically. During this meeting, the “Amsterdam Delphi Method” was utilized including controlled acquisition of feedback, aggregation of responses and iteration. Results: Recommendations or statements were provided for 58 questions. In the judgment of the experts, 17 questions provided no additional useful information and it was agreed to exclude them. With the exception of 3 recommendations (64%, 66%, and 66% respectively), consensus (>70%) was reached for 55 statements and recommendations. Several highlights: polysomnography is the gold standard for diagnosing OSA; continuous positive airway pressure is recommended for all patients with moderate and severe OSA; OSA patients should be continuously monitored with pulse oximetry in the early postoperative period; perioperative usage of sedatives and opioids should be minimized. Conclusion: This first international expert meeting provided 58 statements and recommendations for a clinical consensus guideline regarding the perioperative management of OSA patients undergoing MBS