Effects of Diet versus Gastric Bypass on Metabolic Function in Diabetes.

BACKGROUND: Some studies have suggested that in people with type 2 diabetes, Roux-en-Y gastric bypass has therapeutic effects on metabolic function that are independent of weight loss. METHODS: We evaluated metabolic regulators of glucose homeostasis before and after matched (approximately 18%) weight loss induced by gastric bypass (surgery group) or diet alone (diet group) in 22 patients with obesity and diabetes. The primary outcome was the change in hepatic insulin sensitivity, assessed by infusion of insulin at low rates (stages 1 and 2 of a 3-stage hyperinsulinemic euglycemic pancreatic clamp). Secondary outcomes were changes in muscle insulin sensitivity, beta-cell function, and 24-hour plasma glucose and insulin profiles. RESULTS: Weight loss was associated with increases in mean suppression of glucose production from baseline, by 7.04 µmol per kilogram of fat-free mass per minute (95% confidence interval [CI], 4.74 to 9.33) in the diet group and by 7.02 µmol per kilogram of fat-free mass per minute (95% CI, 3.21 to 10.84) in the surgery group during clamp stage 1, and by 5.39 (95% CI, 2.44 to 8.34) and 5.37 (95% CI, 2.41 to 8.33) µmol per kilogram of fat-free mass per minute in the two groups, respectively, during clamp stage 2; there were no significant differences between the groups. Weight loss was associated with increased insulin-stimulated glucose disposal, from 30.5±15.9 to 61.6±13.0 µmol per kilogram of fat-free mass per minute in the diet group and from 29.4±12.6 to 54.5±10.4 µmol per kilogram of fat-free mass per minute in the surgery group; there was no significant difference between the groups. Weight loss increased beta-cell function (insulin secretion relative to insulin sensitivity) by 1.83 units (95% CI, 1.22 to 2.44) in the diet group and by 1.11 units (95% CI, 0.08 to 2.15) in the surgery group, with no significant difference between the groups, and it decreased the areas under the curve for 24-hour plasma glucose and insulin levels in both groups, with no significant difference between the groups. No major complications occurred in either group. CONCLUSIONS: In this study involving patients with obesity and type 2 diabetes, the metabolic benefits of gastric bypass surgery and diet were similar and were apparently related to weight loss itself, with no evident clinically important effects independent of weight loss. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT02207777.).

Infection prevention plan to decrease surgical site infections in bariatric surgery patients.

BACKGROUND: Surgical site infections (SSI) are one of the most common complications of bariatric surgery. The Metabolic and Bariatric Surgery Accreditation and Quality Improvement (QI) Program (MBSAQIP) allows accredited programs to develop processes for quality improvement based on data collection. The objective of this study was to decrease SSI rates in patients undergoing bariatric surgery at an accredited MBSAQIP center. METHODS: Using the MBSAQIP semiannual report, SSI rates were retrospectively reviewed. Baseline SSI rates were collected from 01/01/2014-12/31/2015. On 01/01/2016, the first infection prevention protocol (IPP-1) was created that included 4% chlorhexidine gluconate (CHG) showers, CHG wipes immediately prior to surgery, and routine cultures of SSIs. An updated IPP (IPP-2) was implemented on 09/01/2016, which discontinued routine surgical drain placement and broadened antibiotic coverage for penicillin allergic patients. RESULTS: During baseline data collection, SSI rates were 5.1%. After the implementation of IPP-1, SSI rates trended down to 2.5%. After implementation of IPP-2, SSI rates decreased significantly to 1.5%, a 66% relative risk reduction in SSIs from baseline. On multivariate regression analysis, the perioperative factors associated with an increased risk for SSIs included diabetes mellitus, intraoperative surgical drain placement, the number of hypertension medications prior to bariatric surgery, and an open approach. CONCLUSIONS: Our study demonstrates that the implementation of a specific protocol for reducing SSIs is safe and feasible in patients undergoing bariatric surgery. We also identified that the success of the IPP is likely centered on the elimination of routine drain placement during primary bariatric procedures.

Testing a model of body image in the bariatric surgery patient.

PURPOSE: The purpose was to test a published model of body image in the bariatric surgery patient in the clinical office setting. BACKGROUND: A model was created based on clinical observations during field work and the literature. It focuses on five concepts of body image: body attitude, body checking, appearance orientation, perceived body size, and perceived body space. Testing this model 3 months after surgery is important because morphology changes rapidly influencing early changes in body image, yet there is a paucity of research at this time point. METHODS: For this study of 67 bariatric surgery patients, sequential sampling was used. Body image and anthropometric measures (body mass index and other weight loss indicators) were obtained at baseline and 3-months postoperatively. Established model testing criteria were used. RESULTS: Over 3 months, mean body mass index was significantly reduced. Mean body image was significantly improved regarding all concepts in the model, except body checking. Body image improvement varied widely when individual responses were examined. CONCLUSIONS: The model was successfully tested. Data on the five concepts in the model provided a body image profile at 3 months indicating individuals' degree of improvement. Areas of non-improvement in the early postoperative phase may signal the need for interventions, like support or psychological counseling, for patients who might be struggling with views of themselves after surgery. Preliminary recommendations are made regarding several of the instruments and their use clinically. Researchers should take into consideration the study's short 3-month time frame when designing future studies.

Conceptualization of body image in the bariatric surgery patient.

Bariatric (weight loss) surgery is more popular than ever. The American Society for Metabolic and Bariatric Surgery in 2016 reported that 216,000 bariatric procedures were performed in the United States. Bariatric surgery has major physiological benefits; its use is expected to increase globally. However, patients may not anticipate the profound impact that rapid and massive weight loss may have on their body image after bariatric surgery. The construct of body image in this population needs to be explicated to facilitate continued research regarding this increasingly prevalent healthcare procedure. This article describes the formulation of a model of relevant concepts and dimensions within the construct of body image in the bariatric surgery patient. In the process of creating the model, we identified many factors influencing body image in patients before and after bariatric surgery, summarized eight measures, and developed a new definition based on prior work. Theoretical considerations are discussed. The long-term objective of this model building approach is to encourage researchers and clinicians to test the feasibility of systematic clinical measurement of body image at office visits before as well as multiple times after bariatric surgery.

Association between specific adipose tissue CD4+ T-cell populations and insulin resistance in obese individuals.

BACKGROUND & AIMS: An increased number of macrophages in adipose tissue is associated with insulin resistance and metabolic dysfunction in obese people. However, little is known about other immune cells in adipose tissue from obese people, and whether they contribute to insulin resistance. We investigated the characteristics of T cells in adipose tissue from metabolically abnormal insulin-resistant obese (MAO) subjects, metabolically normal insulin-sensitive obese (MNO) subjects, and lean subjects. Insulin sensitivity was determined by using the hyperinsulinemic euglycemic clamp procedure. METHODS: We assessed plasma cytokine concentrations and subcutaneous adipose tissue CD4(+) T-cell populations in 9 lean, 12 MNO, and 13 MAO subjects. Skeletal muscle and liver samples were collected from 19 additional obese patients undergoing bariatric surgery to determine the presence of selected cytokine receptors. RESULTS: Adipose tissue from MAO subjects had 3- to 10-fold increases in numbers of CD4(+) T cells that produce interleukin (IL)-22 and IL-17 (a T-helper [Th] 17 and Th22 phenotype) compared with MNO and lean subjects. MAO subjects also had increased plasma concentrations of IL-22 and IL-6. Receptors for IL-17 and IL-22 were expressed in human liver and skeletal muscle samples. IL-17 and IL-22 inhibited uptake of glucose in skeletal muscle isolated from rats and reduced insulin sensitivity in cultured human hepatocytes. CONCLUSIONS: Adipose tissue from MAO individuals contains increased numbers of Th17 and Th22 cells, which produce cytokines that cause metabolic dysfunction in liver and muscle in vitro. Additional studies are needed to determine whether these alterations in adipose tissue T cells contribute to the pathogenesis of insulin resistance in obese people.

Intrahepatic diacylglycerol content is associated with hepatic insulin resistance in obese subjects.

Data from studies in animal models indicate that certain lipid metabolites, particularly diacylglycerol, ceramide, and acylcarnitine, disrupt insulin action. We evaluated the relationship between the presence of these metabolites in the liver (assessed by mass spectrometry) and hepatic insulin sensitivity (assessed using a hyperinsulinemic-euglycemic clamp with stable isotope tracer infusion) in 16 obese adults (body mass index, 48 ± 9 kg/m²). There was a negative correlation between insulin-mediated suppression of hepatic glucose production and intrahepatic diacylglycerol (r = -0.609; P = .012), but not with intrahepatic ceramide or acylcarnitine. These data indicate that intrahepatic diacylglycerol is an important mediator of hepatic insulin resistance in obese people with nonalcoholic fatty liver disease.

ß Cell function after Roux-en-Y gastric bypass surgery or reduced energy intake alone in people with obesity.

BackgroundThe effects of diet-induced weight loss (WL) and WL after Roux-en-Y gastric bypass (RYGB) surgery on ß cell function (BCF) are unclear because of conflicting results from different studies, presumably because of differences in the methods used to measure BCF, the amount of WL between treatment groups, and baseline BCF. We evaluated the effect of WL after RYGB surgery or reduced energy intake alone on BCF in people with obesity with and without type 2 diabetes.MethodsBCF (insulin secretion in relationship to plasma glucose) was assessed before and after glucose or mixed-meal ingestion before and after (a) progressive amounts (6%, 11%, 16%) of WL induced by a low-calorie diet (LCD) in people with obesity without diabetes, (b) ~20% WL after RYGB surgery or laparoscopic adjustable gastric banding (LAGB) in people with obesity without diabetes, and (c) ~20% WL after RYGB surgery or LCD alone in people with obesity and diabetes.ResultsDiet-induced progressive WL in people without diabetes progressively decreased BCF. Marked WL after LAGB or RYGB in people without diabetes did not alter BCF. Marked WL after LCD or RYGB in people with diabetes markedly increased BCF, without a difference between groups.ConclusionMarked WL increases BCF in people with obesity and diabetes but not in people with obesity without diabetes. The effect of RYGB-induced WL on BCF is not different from the effect of matched WL after LAGB or LCD alone.trial registrationNCT00981500, NCT02207777, NCT01299519.FundingNIH grants R01 DK037948, P30 DK056341, P30 DK020579, UL1 TR002345.

Heterogeneity in the effect of marked weight loss on metabolic function in women with obesity.

BACKGROUNDThere is considerable heterogeneity in the effect of weight loss on metabolic function in people with obesity.METHODSWe evaluated muscle and liver insulin sensitivity, body composition, and circulating factors associated with insulin action before and after approximately 20% weight loss in women identified as "Responders" (n = 11) or "Non-responders" (n = 11), defined as the top (>75% increase) and bottom (<5% increase) quartiles of the weight loss-induced increase in glucose disposal rate (GDR) during a hyperinsulinemic-euglycemic clamp procedure, among 43 women with obesity (BMI: 44.1 ± 7.9 kg/m2).RESULTSAt baseline, GDR, which provides an index of muscle insulin sensitivity, and the hepatic insulin sensitivity index were more than 50% lower in Responders than Non-responders, but both increased much more after weight loss in Responders than Non-responders, which eliminated the differences between groups. Weight loss also caused greater decreases in intrahepatic triglyceride content and plasma adiponectin and PAI-1 concentrations in Responders than Non-responders and greater insulin-mediated suppression of plasma free fatty acids, branched-chain amino acids, and C3/C5 acylcarnitines in Non-responders than Responders, so that differences between groups at baseline were no longer present after weight loss. The effect of weight loss on total body fat mass, intra-abdominal adipose tissue volume, adipocyte size, and circulating inflammatory markers were not different between groups.CONCLUSIONThe results from our study demonstrate that the heterogeneity in the effects of marked weight loss on muscle and hepatic insulin sensitivity in people with obesity is determined by baseline insulin action, and reaches a ceiling when "normal" insulin action is achieved.TRIAL REGISTRATIONNCT00981500, NCT01299519, NCT02207777.FUNDINGNIH grants P30 DK056341, P30 DK020579, P30 DK052574, UL1 TR002345, and T32 HL13035, the American Diabetes Association (1-18-ICTS-119), the Longer Life Foundation (2019-011), and the Atkins Philanthropic Trust.

Steatosis drives monocyte-derived macrophage accumulation in human metabolic dysfunction-associated fatty liver disease.

Background & Aims: Metabolic dysfunction-associated fatty liver disease (MAFLD) is a common complication of obesity with a hallmark feature of hepatic steatosis. Recent data from animal models of MAFLD have demonstrated substantial changes in macrophage composition in the fatty liver. In humans, the relationship between liver macrophage heterogeneity and liver steatosis is less clear. Methods: Liver tissue from 21 participants was collected at time of bariatric surgery and analysed using flow cytometry, immunofluorescence, and H&E microscopy. Single-cell RNA sequencing was also conducted on a subset of samples (n = 3). Intrahepatic triglyceride content was assessed via MRI and tissue histology. Mouse models of hepatic steatosis were used to investigate observations made from human liver tissue. Results: We observed variable degrees of liver steatosis with minimal fibrosis in our participants. Single-cell RNA sequencing revealed four macrophage clusters that exist in the human fatty liver encompassing Kupffer cells and monocyte-derived macrophages (MdMs). The genes expressed in these macrophage subsets were similar to those observed in mouse models of MAFLD. Hepatic CD14+ monocyte/macrophage number correlated with the degree of steatosis. Using mouse models of early liver steatosis, we demonstrate that recruitment of MdMs precedes Kupffer cell loss and liver damage. Electron microscopy of isolated macrophages revealed increased lipid accumulation in MdMs, and ex vivo lipid transfer experiments suggested that MdMs may serve a distinct role in lipid uptake during MAFLD. Conclusions: The human liver in MAFLD contains macrophage subsets that align well with those that appear in mouse models of fatty liver disease. Recruited myeloid cells correlate well with the degree of liver steatosis in humans. MdMs appear to participate in lipid uptake during early stages of MALFD. Impact and implications: Metabolic dysfunction associated fatty liver disease (MAFLD) is extremely common; however, the early inflammatory responses that occur in human disease are not well understood. In this study, we investigated macrophage heterogeneity in human livers during early MAFLD and demonstrated that similar shifts in macrophage subsets occur in human disease that are similar to those seen in preclinical models. These findings are important as they establish a translational link between mouse and human models of disease, which is important for the development and testing of new therapeutic approaches for MAFLD.

National Trends in Pediatric Metabolic and Bariatric Surgery: 2010-2017.

BACKGROUND: The childhood obesity epidemic has grown exponentially and is known to disproportionately affect minority groups. Successful treatment of this complex health issue requires a multidisciplinary approach including metabolic and bariatric surgery (MBS) for qualifying pediatric patients. This study examines current national trends in pediatric bariatric surgery from 2010 to 2017 using the National Inpatient Sample. METHODS: This study analyzed MBS among pediatric patients <19 years old using weighted discharge data from 2010 to 2017. The primary outcome was national procedure rates. Secondary analyses included procedure type, demographics, BMI, comorbidities, length of stay, and complication rates. RESULTS: From 2010 to 2017, annual bariatric procedure rates increased from 2.29 to 4.62 per 100 000 (P < .001). Laparoscopic sleeve gastrectomy outpaced Roux-en-Y gastric bypass and laparoscopic adjustable gastric band over time (0.31-3.99 per 100 000, P < .0001). The mean age was stable over time 18.10-17.96 (P = .78). The cohort was primarily female (76.5% to 75.4%), white (54.0% to 45.0%), and privately-insured (59.9% to 53.4%). Preoperative BMI increased from 2010 to 2017 (P < .001), whereas number of obesity-related comorbidities was stable (P > .05). Length of stay was <2 days (2.02-1.75, P = .04) and in-hospital complication rates were low (7.2% to 6.45%, P = .88). CONCLUSIONS: Pediatric MBS is underutilized nationally with disproportionately lower rates among minority groups. Despite incremental progress, further investigation into the racial and social determinants that limit access to pediatric weight loss surgery is critical.

10-year weight loss outcomes after Roux-en-Y gastric bypass and attendance at follow-up visits: a single-center study.

BACKGROUND: Long-term durability of weight loss is a prerequisite for a greater acceptance of bariatric surgery. OBJECTIVES: To examine long-term weight trajectory in patients undergoing Roux-en-Y gastric bypass (RYGB) and determine factors predicting long-term follow-up and weight outcomes. SETTING: University hospital. METHODS: A retrospective cohort of adults who underwent RYGB during 1997-2010 were identified and followed until 2017. Predictors for attendance at periodic follow-up visits, reduction in body mass index (BMI), and percent excess BMI lost were determined using multivariable logistic regression and linear mixed-effects models. The latter was used to predict long-term weight outcomes for a typical patient. RESULTS: The study included 1104 patients with a mean age of 45.5 (standard deviation [SD] 9.9) years and a preoperative BMI of 54.7 (SD 10.9) kg/m2. Follow-up data were available for 92.8% of the patients after 1 year, 50.0% after 5 years, and 35.2% after 10 years post-surgery. Black patients, compared with White patients, were less likely to attend follow-up visits. Attendance at follow-up visits at least every other year was not associated with larger weight loss, but higher preoperative BMI, being White (versus Black), and female sex were. Predicted BMI reduction for a typical patient, a 45-year-old White female with a preoperative BMI of 54.7 kg/m2 and private health insurance, undergoing laparoscopic RYGB in 2004, was 18.3 (standard error [SE] .36) kg/m2 at year 5 and 17.6 (SE .49) kg/m2 at year 10. CONCLUSION: RYGB results in clinically significant and durable weight loss. Attendance at periodic follow-up visits does not appear to be associated with long-term weight loss outcomes. Future work should focus on strategies to remove barriers to post-operative care.

Collagen type I:III ratio of the gastroesophageal junction in patients with paraesophageal hernias.

BACKGROUND: The purpose of this study was to examine the biological environment of the esophageal hiatus through analysis of the collagen content within the gastrohepatic ligament (GHL), gastrophrenic ligament (GPL), and phrenoesophageal ligament (PEL) in patients with type I hiatal hernias (HH) and type III paraesophageal hernias (PEH). METHODS: A control group (N=10) and patients with type I HH (N=10) and type III PEH (N=10) were included in the analysis. Specimens of the GHL, PEL, and GPL were collected intraoperatively. Slides stained with sirius red/fast green were created and ten photos at 400×magnification were taken of each specimen. Axiovision 4.7 (Zeiss) photo analysis software was employed for quantification of collagen I (red) and III (green) by calculating color area (µm2). Statistical significance (p<0.05) was determined using a one-way ANOVA and Fisher's LSD post-test. RESULTS: Cross-polarization microscopy revealed that the collagen I content was similar in the three study groups for the GHL, greater in the type III PEH group and in the control group compared to the type I HH group for the PEL, and greater in the type III PEH group compared to control group for the GPL. Collagen III quantity was greater in the control group than in the type I HH group for each ligament, and greater in the GHL and PEL when compared to the type III PEH group. Type III PEH patients had greater collagen III quantity than did type I HH patients for each ligament. Collagen type I:III ratio of the GHL was greater in both hernia groups compared to the control group. Type III PEH patients contained a higher I:III ratio than both the control and type I HH groups with respect to the PEL. There was no difference in the ratio with evaluation of the GPL for the three groups. CONCLUSION: Evaluation of the esophageal hiatus revealed that patients with PEH have a different biological environment with regard to collagen content compared to control patients. The collagen I:III ratio of the study groups was equal to or greater than the control group. Collagen deficiency in the GE junction supporting ligaments does not appear to be an etiology of PEH formation.

Clinical outcomes of atypical extra-esophageal reflux symptoms following laparoscopic antireflux surgery.

INTRODUCTION: While it is well established that antireflux surgery is effective in relieving typical gastroesophageal reflux disease (GERD) symptoms such as heartburn and regurgitation, it is currently unclear whether atypical symptoms (cough, hoarseness, wheeze) foreshadow a less satisfactory outcome following laparoscopic antireflux surgery (LARS). The purpose of this study is to critically analyze the clinical outcomes of atypical symptoms in patients undergoing LARS. METHODS: Patients scheduled for LARS for GERD were prospectively enrolled over a 7-year period; all subjects underwent preoperative high-resolution manometry (HRM) and had evidence of GERD on ambulatory pH study. Cough, wheeze, and hoarseness were considered atypical symptoms. During preoperative and postoperative examinations, patients completed detailed foregut symptomatology questionnaires, using both 5-point Likert and 10-point visual analog scales (VAS) to document typical as well as atypical symptoms. Atypical symptom burden was calculated as a sum of VAS for the three atypical symptoms, termed the atypical score (ATS). HRM patterns were grouped into normal, spastic, and hypomotile. Statistical significance (p < 0.05) was determined using paired t-test, and analysis of variance with post hoc least significant difference (LSD). RESULTS: One hundred thirteen patients (age 49 ± 1.26 years, range 20-84 years, M:F 47:66) with mean follow-up of 28 ± 2.31 months (range 1-92 months) fulfilled inclusion criteria, having mean modified DeMeester score of 45.5 ± 2.78. Heartburn was noted in 84.1%, while atypical symptoms of some degree were reported by 92.0% (104 patients). Heartburn improved from a preoperative score of 7.1 ± 0.54 to 0.9 ± 0.24 after LARS, and ATS improved from 8.9 ± 0.71 to 2.2 ± 0.42. Significant improvements were noted for all atypical symptoms analyzed (p < 0.0001 for each). Improvement in atypical symptoms was least in the presence of hypomotility features on HRM (21.7% improvement), compared with normal motility (72.4%) and spastic features (83.9%). Preoperative atypical score (p < 0.0001) and esophageal hypomotility (p = 0.04) demonstrated a linear relationship with postoperative atypical score. CONCLUSIONS: In an unselected cohort of patients undergoing LARS, atypical GERD symptoms improved as significantly as typical symptoms. Symptom improvement was significantly lower in the presence of esophageal hypomotility and with higher symptomatic state. Therefore, patients with severe atypical symptoms or hypomotile esophagus may not achieve the same clinical satisfaction from LARS.

Systematic Review and Meta-Analysis of the Effectiveness of Insurance Requirements for Supervised Weight Loss Prior to Bariatric Surgery.

Many insurance plans impose strict criteria mandating preoperative weight loss attempts to limit patient's access to surgery. Preoperative acute weight loss has been hypothesized to reduce perioperative risk and to identify compliant patients who may have improved long-term weight loss. In this review, the evidence from studies examining clinical and weight loss outcomes both with and without preoperative weight loss are summarized. Although preoperative weight loss may have modest impact on some factors related to perioperative conduct, the evidence does not support these programs' effectiveness at promoting long-term weight loss. Provision of weight loss surgery should not be contingent on completion of insurance-mandated weight loss goals preoperatively, and these programs may, through patient attrition, actually do more harm than good.

Understanding the Current Role of Robotic-Assisted Bariatric Surgery.

BACKGROUND: The role of robotic surgery in bariatrics remains controversial. Patient selection for robotic surgery is not well-studied. The objective of this study was to identify factors associated with robotic surgery and its temporal trends. METHODS: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database from 2015 to 2018 was used. Adult patients undergoing primary sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) using the laparoscopic or robotic approach were identified. Revisional, hybrid, or those with concomitant procedures were excluded. Logistic regression was conducted to identify factors associated with undergoing robotic-assisted surgery. RESULTS: Among 211,568 patients who underwent SG, 9.1% underwent a robotic SG; among 76,805 patients who underwent RYGB, 7.9% of patients underwent a robotic RYGB. During 2015-2018, robotics increased from 7.1 to 11.3% for SG and 7.4 to 8.6% for RYGB. After controlling for patient characteristics, there was still an increasing trend in the use of robotic surgery: SG (multivariable-adjusted odds ratio, aOR, 1.18; 95% confidence interval, CI, 1.17-1.20) and RYGB (aOR, 1.05; 95% CI, 1.03-1.08). For both robotic SG and RYGB, functional status and African American race were associated with undergoing robotic surgery, while races other than White or African American and Hispanic ethnicity were not. Pre-operative IVC filter was associated with robotic SG, while the presence of GERD, diabetes, and COPD were associated with robotic RYGB. CONCLUSIONS: Robotic bariatric surgery has increased over time. Our findings identified factors associated with the receipt of robotic surgery. Reasons for these factors require further investigation to better delineate indications for this technology.

The Risks of Stone Diagnosis and Stone Removal Procedure After Different Bariatric Surgeries.

Introduction: Nephrolithiasis is common after malabsorptive bariatric surgery; however, the comparative risk of stone formation after different bariatric surgeries remains unclear. We seek to compare the risk of stone diagnosis and stone procedure after gastric banding (GB), sleeve gastrectomy (SG), short-limb Roux-en-Y (SLRY), long-limb Roux-en-Y (LLRY), and biliopancreatic diversion with duodenal switch (BPDDS). Patients and Methods: Using an administrative database, we retrospectively identified 116,304 patients in the United States, who received bariatric surgery between 2007 and 2014, did not have a known kidney stone diagnosis before surgery, and were enrolled in the database for at least 1 year before and after their bariatric surgery. We used diagnosis and procedural codes to identify comorbidities and events of interest. Our primary analysis was performed with extended Cox proportional hazards models using time to stone diagnosis and time to stone procedure as outcomes. Results: The adjusted hazard ratio of new stone diagnosis from 1 to 36 months, compared to GB, was 4.54 for BPDDS (95% confidence interval [CI] 3.66-5.62), 2.12 for LLRY (95% CI 1.74-2.58), 2.15 for SLRY (95% CI 2.02-2.29), and 1.35 for SG (95% CI 1.25-1.46). Similar results were observed for risk of stone diagnosis from 36 to 60 months, and for risk of stone removal procedure. Male sex was associated with an overall 1.63-fold increased risk of new stone diagnosis (95% CI 1.55-1.72). Conclusions: BPDDS was associated with a greater risk of stone diagnosis and stone procedures than SLRY and LLRY, which were associated with a greater risk than restrictive procedures. Nephrolithiasis is more common after more malabsorptive bariatric surgeries, with a much greater risk observed after BPDDS and for male patients.

Prospective evaluation of adhesion characteristics to intraperitoneal mesh and adhesiolysis-related complications during laparoscopic re-exploration after prior ventral hernia repair.

BACKGROUND: The purpose of this study was to characterize the adhesion characteristics of absorbable- and nonabsorbable-barrier-coated meshes and to report adhesiolysis-related complications during laparoscopic re-exploration after prior ventral hernia repair. METHODS: Under an IRB-approved protocol, patients undergoing laparoscopic re-exploration after prior intraperitoneal mesh placement were prospectively graded intraoperatively for adhesion tenacity (0-4), adhesion surface area (0 = 0%, 10 = 100%), and ratio of adhesiolysis time to mesh surface area (min/cm(2)). Adhesiolysis-related complications were also recorded. Data are given as mean ± SD. Statistical significance (P < 0.05) was determined using the t test and Fisher's exact test. RESULTS: From March 2006 to March 2009, 69 patients underwent laparoscopic surgery after prior intraperitoneal mesh placement for ventral hernia repair. Previous meshes were absorbable-barrier-coated mesh (n = 18), permanent-barrier composite mesh [Composix® (n = 17)], permanent-barrier noncomposite mesh [DualMesh® (n = 14)], uncoated polypropylene mesh (n = 12), and biologic mesh (n = 8). Indications for laparoscopic re-exploration were recurrent ventral hernia (n = 58), chronic pain (n = 3), cholecystectomy (n = 3), parastomal hernia (n = 2), small bowel obstruction (n = 1), nephrectomy (n = 1), and Nissen fundoplication (n = 1). Adhesions to DualMesh were less tenacious (P < 0.05) compared to all other meshes. Surface area of adhesions to DualMesh were less (P < 0.05) than to Composix and to uncoated polypropylene mesh, but not to absorbable-barrier-coated and biologic meshes. Adhesiolysis time:mesh surface area was less (P < 0.05) for DualMesh compared to Composix, uncoated polypropylene, and biologic mesh, but not to absorbable-barrier-coated mesh. Adhesiolysis-related complications occurred in two (16.7%) (P = ns) patients with uncoated polypropylene mesh, one cystotomy and one enterotomy; both were repaired laparoscopically. There were two (16.7%) (P = ns) conversions to an open procedure: one converted patient had Composix (6.7%) and one had absorbable-barrier-coated mesh (5.9%). There were no adhesiolysis-related complications with these meshes. There were no adhesiolysis-related complications or conversions to open in the DualMesh or biologic mesh groups. CONCLUSIONS: Adhesion characteristics of mesh placed intraperitoneally and adhesiolysis-related complications during laparoscopic re-exploration after ventral hernia repair are associated with unique properties of the mesh and/or barrier.

Evaluation of acute fixation strength for mechanical tacking devices and fibrin sealant versus polypropylene suture for laparoscopic ventral hernia repair.

BACKGROUND: The purpose of this comparative study is to evaluate the acute fixation strength of mechanical tacking devices and fibrin sealant against polypropylene suture for laparoscopic ventral hernia repair. METHODS: Three metallic mechanical tacking devices (ProTack, Salute, EndoANCHOR), 4 absorbable tacking devices (AbsorbaTack, PermaSorb, I-Clip, and SorbaFix), and 2 types of fibrin sealant (Tisseel, Artiss) were compared with 0-polypropylene suture. Three constructs from each device or an amount of sealant sufficient to cover a 3 × 3 cm(2) area were used to affix a 4 × 3 cm piece of absorbable barrier-coated mesh (Proceed, Ethicon, Inc) to the peritoneal surface of porcine abdominal wall. Ten samples were completed for each fixation modality. Acute fixation strength was measured via a lap shear test on an Instron tensiometer. RESULTS: Acute fixation strength was significantly greater for suture (59.7 7.2 N) compared with all laparoscopic tacking devices and to fibrin sealant (P < .001 for all comparisons). Protack (29.5 ± 2.8 N) was stronger than Absorbatack (13.2 ± 3.7 N; P = .029). Protack, Permasorb, SorbaFix, and I-clip were stronger than fibrin sealant (P < .05 for all comparisons). CONCLUSIONS: The acute fixation strengths of metallic or absorbable tacks as well as fibrin sealant are all significantly less than that achieved with polypropylene suture. These factors should be considered in selecting the type of mechanical fixation for patients undergoing laparoscopic ventral hernia repair.

Assessment of postoperative nausea and vomiting after bariatric surgery using a validated questionnaire.

BACKGROUND: Postoperative nausea and vomiting (PONV) is known to occur after bariatric surgery, with over two thirds of patients affected. However, variability exists in how to objectively measure PONV. OBJECTIVES: The goals of the present study were to use a validated, patient-centered scoring tool, the Rhodes Index of Nausea, Vomiting, and Retching to measure the severity of PONV after bariatric surgery, to directly compare PONV between patients who underwent laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB), and to identify risk factors for the development of PONV after bariatric surgery. SETTING: Barnes-Jewish Hospital/Washington University School of Medicine, St. Louis, Missouri, United States of America. METHODS: The Washington University Weight Loss Surgery team prospectively surveyed patients from January 1, 2017 to December 1, 2018 at the following 6 different timepoints: postoperative day (POD) 0, POD 1, POD 2, POD 3 to 4, the first postoperative outpatient visit (POV 1: POD 5-25), and the second postoperative visit (POV 2: POD 25-50). At each timepoint, a cumulative Rhodes score was calculated from the sum of 8 questions. The American Society for Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database was used to collect patient demographic characteristics and perioperative clinical data. RESULTS: A total of 274 patients met study criteria and completed 605 Rhodes questionnaires. Two hundred fifty Rhodes questionnaires were completed by patients after SG and 355 were completed by patients after LRYGB. Total Rhodes scores are statistically higher in LSG patients compared with patients who underwent LRYGB (LSG = 5.45 ± 6.27; LRYGB = 3.08 ± 4.19, P = .0002). Additionally, at the earlier timepoints, scores were higher among patients who underwent LSG than those who had undergone LRYGB as follows: POD 0 (LSG = 6.96 ± 6.50; LRYGB = 2.89 ± 2.90, P = .0115), POD 1 (LSG = 8.20 ± 6.76; LRYGB = 2.88 ± 3.44, P < .0001), and POD 2 (LSG = 4.05 ± 4.88; LRYGB = 2.06 ± 3.43, P = .05). On subset analysis, examining patients who either underwent an LSG or LRYGB, both procedures had a statistically significant PONV peak emerge on POV 2. Last, overall Rhodes scores were statistically higher in female patients compared with male patients (female: 4.43 ± 5.46; male: 2.35 ± 3.90, P = .021). Although the magnitude of the difference varied somewhat across POD time intervals, the difference was most pronounced at POV 2. CONCLUSIONS: This is the largest study using a validated nausea and vomiting questionnaire to objectively measure PONV after bariatric surgery. The factors found to be most associated with increased PONV were LSG and female sex. Ultimately, these data can help bariatric surgery programs, including Washington University Weight Loss Surgery, identify patients who may require more intensive treatment of PONV, particularly POD 0 to 2, and help to identify patients that continue to struggle with PONV in the later surgical recovery phase.