Gastric per-oral endoscopic myotomy (G-POEM) for the treatment of gastric sleeve stenosis: a feasibility and safety study

BACKGROUND

Traditional endoscopic treatments have limited success in gastric sleeve stenosis (GSS). Gastric peroral endoscopic myotomy (G-POEM) could conceivably obliterate the twist/angulation that causes GSS through a tunneled stricturotomy. We report early outcomes of G-POEM for GSS treatment.

METHODS

We retrospectively reviewed all patients with GSS treated with G-POEM at our center. The primary end point was clinical success, defined as symptom improvement with resumption of adequate oral intake, without requiring further intervention.

RESULTS

13 patients (mean age 43 ± 10.9 years; 12 female) underwent G-POEM for predominantly helical (11/13, 85 %) GSS. Three (23 %) had concurrent sleeve leak and 10 (77 %) had prior GSS treatment. Two intraoperative complications occurred, with no deviation to the procedure; no major complications occurred. At median follow-up of 175 (interquartile range [IQR] 119-260) days, clinical success was achieved in 10 patients (77 %). Median Gastroparesis Cardinal Symptom Index score in responders decreased from 2.06 (IQR 1.5-2.8) to 0.39 (IQR 0.2-0.5). Three patients (23 %) required surgical revision.

CONCLUSIONS

G-POEM was feasible and safe, and may provide an alternative option for those averse to undergoing surgical revision for treatment of GSS.

Obesity is associated with copper elevation in serum and tissues

Copper misbalance has been linked to fat accumulation in animals and experimental systems; however, information about copper homeostasis in human obesity is limited. In this study, the copper status of obese individuals was evaluated by measuring their levels of copper and cuproproteins in serum, adipose and hepatic tissues. The analysis of serum trace elements showed significant positive and element-specific correlation between copper and BMI after controlling for gender, age, and ethnicity. Serum copper also positively correlated with leptin, insulin, and the leptin/BMI ratio. When compared to lean controls, obese patients had elevated circulating cuproproteins, such as semucarbazide-sensitive amine oxidase (SSAO) and ceruloplasmin, and higher SSAO activity and copper levels in visceral fat. Although hepatic steatosis reduces copper levels in the liver, obese patients with no or mild steatosis have higher copper content in the liver compared to lean controls. In conclusion, obese patients evaluated in this study had altered copper status. Strong positive correlations of copper levels with BMI and leptin suggest that copper and/or cuproproteins may be functionally linked to fat accumulation.

Providing complex GI surgical care with minimally invasive approaches: a survey of the practice patterns of Fellowship Council alumni

INTRODUCTION

The Fellowship Council (FC) oversees 172 non-ACGME surgical fellowships offering 211 fellowship positions per year. These training programs cover multiple specialties including Advanced gastrointestinal (GI), Advanced GI/MIS, Bariatric, Hepatopancreaticobiliary (HPB), Flexible Endoscopy, Colorectal, and Thoracic Surgery. Although some data have been published detailing the practice environments (i.e., urban vs. rural) and yearly total case volumes of FC alumni, there is a lack of granular data regarding the practice patterns of FC graduates. The aim of this study was to gather detailed data on the specific case types performed and surgical approaches employed by recent FC alumni.

METHODS

A 21-item survey covering 64 data points was emailed to 835 FC alumni who completed their fellowship between 2013 and 2017. Email addresses were obtained from FC program directors and FC archives.

RESULTS

We received 327 responses (39% response rate). HPB, Advanced Colorectal, and Advanced Thoracic alumni appear to establish practices focused on their respective fields. Graduates from Advanced GI, Adv GI/MIS, and Bariatric programs appear to build practices with a mix of several complex GI case types including bariatrics, colorectal, foregut, HPB, and hernia cases.

CONCLUSIONS

This is the first large data set to provide granular information on the practice patterns of FC alumni. FC trained surgeons perform impressive volumes of complex procedures, and minimally invasive approaches are extremely prevalent in these practices. Further, many graduates carve out practices with large footprints in robotics and endoscopy.

Cytokine, Chemokine, and Cytokine Receptor Changes Are Associated With Metabolic Improvements After Bariatric Surgery

CONTEXT

Altered cytokine levels and chronic low-grade inflammation contribute to metabolic dysfunction in obesity. The extent of cytokine changes and their impact on metabolic improvements after bariatric surgery have not been fully explored.

OBJECTIVE

To compare 76 circulating cytokines, chemokines, and secreted cytokine receptors in subjects with obesity and lean subjects and determine how these cytokines are altered by bariatric surgery.

DESIGN, SETTING, AND PARTICIPANTS

A total of 37 patients with obesity and 37 lean patients in a cross-sectional study at an academic medical center. We also investigated cytokine changes in 25 patients with obesity after bariatric surgery.

INTERVENTION

Bariatric surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy).

MAIN OUTCOME MEASURES

Quantification of 76 circulating cytokines, chemokines, and secreted cytokine receptors.

RESULTS

A total of 13 cytokines were significantly higher, and 4 lower, in patients with obesity relative to lean controls. Soluble vascular endothelial growth factor receptor 2 (sVEGFR2), soluble TNF receptor (sTNFR) 1, and sTNFR2 were positively correlated, and soluble receptor for advanced glycation end-products was inversely correlated, with weight and body mass index. sTNFR2 was positively correlated with fasting glucose, homeostatic model assessment of insulin resistance, and hemoglobin A1c. After bariatric surgery, adiponectin increased, and leptin decreased. Elevated sVEGFR2 levels in patients with obesity were decreased (P = 0.01), whereas reduced chemokine (C-X-C motif) ligand (CXCL) 12 levels in patients with obesity increased (P = 0.03) after surgery. Patients with higher soluble interleukin receptor (sIL) 1R2 and sIL-6R levels before surgery had greater weight loss after surgery (P < 0.05).

CONCLUSIONS

We demonstrate that chemokine (C-C motif) ligand (CCL) 14, sVEGFR2, and platelet-derived growth factor BB are elevated in obesity, and CXCL12, CCL11, and CCL27 are lower in obesity. We found clinically concordant directionality between lean and patients with obesity and before vs after surgery for six cytokines, suggesting that bariatric surgery shifted the cytokine profiles of patients with obesity toward that of lean controls.

The Role of Laboratory Testing in Differentiating Type 1 Diabetes from Type 2 Diabetes in Patients Undergoing Bariatric Surgery

BACKGROUND

It may be difficult to distinguish between adults with type 1 diabetes and type 2 diabetes by clinical assessment. In patients undergoing bariatric surgery, it is critical to correctly classify diabetes subtype to prevent adverse perioperative outcomes including diabetic ketoacidosis. This study aimed to determine whether testing for C-peptide and islet cell antibodies during preoperative evaluation for bariatric surgery could improve the classification of type 1 versus type 2 diabetes compared to clinical assessment alone.

METHODS

This is a retrospective analysis of the Improving Diabetes through Lifestyle and Surgery trial, which randomized patients with clinically diagnosed type 2 diabetes and BMI 30-40 kg/m² to medical weight loss or bariatric surgery; one participant was discovered to have type 1 diabetes after experiencing postoperative diabetic ketoacidosis. Using blood samples collected prior to study interventions, we measured islet cell antibodies and fasting/meal-stimulated C-peptide in all participants.

RESULTS

The participant with type 1 diabetes was similar to the 11 participants with type 2 diabetes in age at diagnosis, adiposity, and glycemic control but had the lowest C-peptide levels. Among insulin-treated participants, fasting and stimulated C-peptide correlated strongly with the C-peptide area-under-the-curve on mixed meal tolerance testing (R = 0.86 and 0.88, respectively). Three participants, including the one with type 1 diabetes, were islet cell antibody positive.

CONCLUSIONS

Clinical characteristics did not correctly identify type 1 diabetes in this study. Preoperative C-peptide testing may improve diabetes classification in patients undergoing bariatric surgery; further research is needed to define the optimal C-peptide thresholds.

CTRP7 deletion attenuates obesity-linked glucose intolerance, adipose tissue inflammation, and hepatic stress

Chronic low-grade inflammation and cellular stress are important contributors to obesity-linked metabolic dysfunction. Here, we uncover an immune-metabolic role for C1q/TNF-related protein 7 (CTRP7), a secretory protein of the C1q family with previously unknown function. In obese humans, circulating CTRP7 levels were markedly elevated and positively correlated with body mass index, glucose, insulin, insulin resistance index, hemoglobin A1c, and triglyceride levels. Expression of CTRP7 in liver was also significantly upregulated in obese humans and positively correlated with gluconeogenic genes. In mice, Ctrp7 expression was differentially modulated in various tissues by fasting and refeeding and by diet-induced obesity. A genetic loss-of-function mouse model was used to determine the requirement of CTRP7 for metabolic homeostasis. When fed a control low-fat diet, male or female mice lacking CTRP7 were indistinguishable from wild-type littermates. In obese male mice consuming a high-fat diet, however, CTRP7 deficiency attenuated insulin resistance and enhanced glucose tolerance, effects that were independent of body weight, metabolic rate, and physical activity level. Improved glucose metabolism in CTRP7-deficient mice was associated with reduced adipose tissue inflammation, as well as decreased liver fibrosis and cellular oxidative and endoplasmic reticulum stress. These results provide a link between elevated CTRP7 levels and impaired glucose metabolism, frequently associated with obesity. Inhibiting CTRP7 action may confer beneficial metabolic outcomes in the setting of obesity and diabetes.

Treatment for Vitamin D Deficiency Prior to Bariatric Surgery: a Prospective Cohort Study

BACKGROUND

Since obesity increases vitamin D deficiency (VDD) risk, bariatric surgery candidates are high-risk. Previously, we documented 71.4% VDD at our center.

OBJECTIVES

To investigate diagnosis and treatment for VDD in our bariatric candidates.

METHODS

25(OH)D, if pending, and supplementation (form, dosing, frequency) were prospectively documented in 265 candidates.

RESULTS

Candidates were 83.0% female, 48.9% white, age 43 ± 13 years and BMI 46.3 ± 10.5 kg/m(2). 25(OH)D was available for 18.5%: 35.7% VDD 39.3% insufficiency. VDD history did not differ by demographics or procedure, as with those tested versus not.

CONCLUSION

VDD testing was lower than clinically-indicated. Of those tested, 35.7% were deficient and 39.3% insufficient. We previously reported higher rates: 71.4% deficiency, 92.9% insufficiency. Thus, many candidates are untested but high-risk.

C1q/TNF-Related Protein-9 (CTRP9) Levels Are Associated With Obesity and Decrease Following Weight Loss Surgery

CONTEXT

C1q/TNF-related protein-9 (CTRP9) is a novel adipokine that has beneficial metabolic and cardiovascular effects in various animal models. Alterations in circulating CTRP9 have also been observed in patients with cardiovascular disease and diabetes, but little is known about the impact of obesity and bariatric surgery on CTRP9 concentrations.

OBJECTIVE

The aim of this study was to compare CTRP9 levels in obese and lean subjects and to determine whether circulating CTRP9 levels in morbidly obese patients are altered by bariatric surgery.

DESIGN, SETTING, AND PARTICIPANTS

Fifty-nine obese bariatric surgical patients and 62 lean controls were recruited to participate in a cross-sectional study at an academic medical center. The obese patients were further invited to participate in a cohort study, and 21 returned for analysis at 3 and 6 months postsurgery.

INTERVENTION

Bariatric surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy) was the intervention for this study.

MAIN OUTCOME MEASURES

Fasting serum was obtained from all subjects on entry to the study and was analyzed in the core laboratory for hemoglobin A1c, glucose, aspartate aminotransferase, alanine aminotransferase, total cholesterol, high- and low-density lipoprotein cholesterol, and triglycerides; CTRP9, insulin, adiponectin, and leptin were measured by ELISA. Serum from the patients in the cohort study was also analyzed at 3 and 6 months.

RESULTS

Serum CTRP9 was significantly higher in the obese group compared to the lean group. CTRP9 was associated with obesity, even after controlling for age, gender, and ethnicity. Following bariatric surgery, there was a significant decrease in weight at 3 and 6 months postprocedure, accompanied by decreases in CTRP9, hemoglobin A1c and leptin, and an increase in serum adiponectin.

CONCLUSIONS

CTRP9 levels are elevated in obesity and significantly decrease following weight loss surgery. Our data suggest that CTRP9 may play a compensatory role in obesity, similar to that of insulin, and is down-regulated following weight loss surgery.

Vitamin D status and supplementation before and after bariatric surgery: a comprehensive literature review

BACKGROUND

Bariatric surgery is the most effective long-term weight loss method. The most common procedures are Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG). Bariatric patients are at high risk of vitamin D deficiency (VDD) and insufficiency (VDI), which are associated with skeletal and nonskeletal ailments. There is no consensus regarding the optimal treatment for VDD/VDI in bariatric patients.

OBJECTIVES

To critically examine the literature on vitamin D status (serum 25[OH]D concentrations) pre- and postbariatric surgery as well as supplementation regimens currently used.

METHODS

We searched PubMed, Embase, and Cochrane from inception to May 2015 for articles relating to vitamin D, RYGB, and VSG. Of 208 citations retrieved, 30 were included.

RESULTS

Preoperative VDD (<20 ng/mL) ranged from 13% to 90%, while VDI (<30 ng/mL) was found in up to 98%. Prevalence remained similar postoperatively and was highest after RYGB. Most studies found dosages<800 IU daily insufficient postbariatric surgery. Other studies examined the effectiveness of dosages between 1000 and 5000 IU daily, reaching similar conclusions. Several studies suggested using 50,000 IU weekly plus a daily dose. No studies reported optimization.

CONCLUSIONS

It is widely accepted that serum 25(OH)D concentrations above 30 ng/mL are optimal; however, current postbariatric vitamin D supplementation fails to raise 25(OH)D above that level universally. This review highlights both the great need and the lack of consensus on the optimal supplementation regimen (dosage and frequency) for pre- and postbariatric patients. Future studies should investigate multiple regimens and attempt to identify methods for personalizing these regimens if found necessary.

Proxy measures of vitamin D status - season and latitude - correlate with adverse outcomes after bariatric surgery in the Nationwide Inpatient Sample, 2001-2010: a retrospective cohort study

Objective

To investigate the association between adverse surgical outcomes following bariatric surgery and proxy measures of vitamin D (VitD) status (season and latitude) in the Nationwide Inpatient Sample (NIS).

Background

Obesity is an independent risk factor for VitD deficiency (25(OH)D < 20 ng ml⁻¹). VitD deficiency compounds the chronic inflammation of obesity, increasing the risk of adverse outcomes following bariatric surgery. Epidemiology has long used season and latitude as proxies for group VitD, as VitD status is largely determined by sun exposure, which is greatest during summer and at the Equator.

Methods

We assessed proxy measures of group VitD status. We compared surgeries in VitD Summer (July to September), Winter (January to March), and Fall/Spring (October to December and April to June) and in the North (≥37°N) vs. the South (<37°N).

Results

We identified 932,091 bariatric surgeries; 81.2% were women and 74.4% were white. Sex was unequally distributed by season (p = 0.005). Median age was 43.0 years (all groups). Most surgeries occurred in the North (64.8%). Adverse outcome rates ranged from 0.01% (wound infections) to 39.4% [prolonged length of stay {LOS}]. Season was inversely associated with wound infection (p = 0.018) and dehiscence (p = 0.001). Extended LOS was inversely correlated with season (p < 0.001). These relationships held after adjustment. Prolonged LOS (p < 0.001) and any complication (p = 0.108) were more common in the North.

Conclusions

We have demonstrated a graded relationship between seasonality and adverse outcomes following bariatric surgery. The association was strongest for dehiscence and prolonged LOS. These relationships held when using latitude. A prospective study measuring pre‐operative 25(OH)D concentration would strengthen the case for causality in adverse surgical outcomes.

Lysyl Oxidase as a Serum Biomarker of Liver Fibrosis in Patients with Severe Obesity and Obstructive Sleep Apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is associated with the progression of nonalcoholic fatty liver disease (NAFLD). We hypothesized that the hypoxia of OSA increases hepatic production of lysyl oxidase (LOX), an enzyme that cross-links collagen, and that LOX may serve as a biomarker of hepatic fibrosis.

DESIGN

Thirty-five patients with severe obesity underwent liver biopsy, polysomnography, and serum LOX testing. A separate group with severe OSA had serum LOX measured before and after 3 mo of CPAP or no therapy, as did age-matched controls. LOX expression and secretion were measured in mouse hepatocytes following exposure to hypoxia.

SETTING

The Johns Hopkins Bayview Sleep Disorders Center, and the Hypertension Unit of the Heart Institute at the University of São Paulo Medical School.

MEASUREMENTS AND RESULTS

In the bariatric cohort, the apnea-hypopnea index was higher in patients with hepatic fibrosis than in those without fibrosis (42.7 ± 30.2 events/h, versus 16.2 ± 15.5 events/h; P = 0.002), as was serum LOX (84.64 ± 29.71 ng/mL, versus 45.46 ± 17.16 ng/mL; P < 0.001). In the sleep clinic sample, patients with severe OSA had higher baseline LOX than healthy controls (70.75 ng/mL versus 52.36 ng/mL, P = 0.046), and serum LOX decreased in patients with OSA on CPAP (mean decrease 20.49 ng/mL) but not in untreated patients (mean decrease 0.19 ng/mL). Hypoxic mouse hepatocytes demonstrated 5.9-fold increased LOX transcription (P = 0.046), and enhanced LOX protein secretion.

CONCLUSIONS

The hypoxic stress of obstructive sleep apnea may increase circulating lysyl oxidase (LOX) levels. LOX may serve as a biomarker of liver fibrosis in patients with severe obesity and nonalcoholic fatty liver disease.

Long-term quality of life and risk factors for recurrence after laparoscopic repair of paraesophageal hernia

IMPORTANCE

Laparoscopic repair of paraesophageal hernia (PEH) has been shown to result in excellent relief of symptoms and improved quality of life (QOL) despite a relatively high radiographically identified recurrence rate.

OBJECTIVE

To assess potential risk factors for recurrence and long-term change in QOL after laparoscopic repair of PEH.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective study of 111 patients who underwent elective laparoscopic repair of type III PEH with biological mesh buttressed over a primary cruroplasty from April 3, 2009, through July 31, 2014, at the Department of Surgery, Johns Hopkins University of Medicine. We administered a modified version of a validated gastroesophageal reflux disease-specific QOL tool to patients before and at 2, 12, and 36 months after the procedure. Higher QOL scores represent greater severity of symptoms. An upper gastrointestinal tract barium-contrast radiographic examination was performed at 1 year to assess for recurrence. Demographic factors, comorbidities, and preoperative radiographic findings were analyzed as possible indicators for recurrence using logistic regression.

MAIN OUTCOMES AND MEASURES

Quality of life, measured by the gastroesophageal reflux disease-specific QOL tool, and recurrence, defined as a PEH of greater than 2 cm.

RESULTS

Median patient age was 61 years, 63.1% of patients were women, and 81.1% of patients were white. Four patients required reoperation, of which only 1 was for symptomatic recurrent PEH. The mean follow-up time for the 36-month QOL assessment was 43.5 months. The overall preoperative and 2-, 12-, and 36-month QOL scores were 28.50, 10.18, 9.74, and 10.58, respectively (P < .001). Recurrences were found in 19 of the 70 patients (27%) who completed the 1-year radiographic examination. Compared with baseline, all individual symptoms improved significantly except for early satiety (mean [SD] score, 3.18 [1.88] at baseline vs 2.07 [1.70] at the 36-month follow-up; P = .07), nausea (1.69 [1.63] vs 0.77 [1.25]; P = .08), pain with swallowing (1.06 [1.50] vs 0.53 [0.90]; P = .73), and bloating/gas (3.28 [1.71] vs 2.23 [1.72]; P = .05) at the 36-month QOL assessment. Although not statistically significant, preoperative hernias containing most of the stomach were more likely to recur after repair when compared with those involving gastric cardia and fundus (odds ratio, 3.74 [95% CI, 0.93-15.14]; P = .06).

CONCLUSIONS AND RELEVANCE

Overall, laparoscopic repair of PEH with biological mesh results in excellent long-term QOL. The cause of recurrence is likely multifactorial and individualized to each patient. Further evaluation of novel techniques and unidentified patient factors is needed.

Lower Circulating C1q/TNF-Related Protein-3 (CTRP3) Levels Are Associated with Obesity: A Cross-Sectional Study

Purpose

C1q/TNF-related protein-3 (CTRP3) is a novel adipokine that lowers blood glucose levels, reduces liver triglyceride synthesis, and is protective against hepatic steatosis in diet-induced obese mouse models. We hypothesized that higher circulating serum levels of CTRP3 would be associated with a lean body mass index (BMI) and a more favorable metabolic profile in humans. The aim of this study was to investigate CTRP3 levels in lean individuals compared to obese individuals.

Methods

This was a cross-sectional study of obese (n=44) and lean control patients (n=60). Fasting metabolic parameters were measured in all patients and serum CTRP3 levels were measured by ELISA.

Results

BMI of the lean group was 21.9 ± 0.2 kg/m² and obese group was 45.2 ± 1.1 kg/m². We found significantly lower circulating levels of CTRP3 in obese individuals (405 ± 8.3 vs. 436± 6.7ng/mL, p=0.004) compared to the lean group. Serum CTRP3 levels were inversely correlated with BMI (p=0.001), and triglycerides (p<0.001), and significantly associated with gender (p<0.01), ethnicity (p=0.05), HDL-cholesterol (p<0.01), and adiponectin (p<0.01). We found BMI (p<0.01), gender (p<0.01), and ethnicity (p<0.05) to be significant predictors of CTRP3 levels when controlling for age in multiple regression analysis.

Conclusions

CTRP3 is a beneficial adipokine whose circulating levels are significantly lower in obese individuals. Obesity causes dysregulation in adipokine production, including the down-regulation of CTRP3. Lower CTRP3 levels may contribute to the pathophysiology of metabolic disorders associated with obesity. Optimizing CTRP3 levels through novel therapies may improve obesity and its comorbidities.

Assessment of postdischarge complications after bariatric surgery: A National Surgical Quality Improvement Program analysis

BACKGROUND

Little is reported about postdischarge complications after bariatric surgery. We sought to identify the rates of postdischarge complications, associated risk factors, and their influence on early hospital readmission.

METHODS

Using the database of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) (2005-2013), we identified patients ≥18 years of age who underwent a bariatric operation with a primary diagnosis of morbid/severe obesity and a body mass index ≥35. The incidence of postdischarge complication was the primary outcome, and hospital readmission was the secondary outcome. The association between postdischarge complications and various patient factors was explored by the use of multivariable logistic regression.

RESULTS

A total of 113,898 patients were identified with an overall postdischarge complication rate of 3.2% within 30 days of operation. The rates decreased from 2005 to 2006 (4.6%) to 2013 (3.0%) (P < .001). On average, postdischarge complications occurred 10 days postoperatively, with wound infection (49.4%), reoperation (30.7%), urinary tract infection (16.9%), shock/sepsis (12.4%), and organ space surgical-site infection (11.0%) being the most common. Patients undergoing open gastric bypass had the greatest postdischarge complication rate of 8.5%. Of those patients experiencing postdischarge complications, 51.6% were readmitted. The overall readmission rate was 4.9%. The factors associated most strongly with increased odds of postdischarge complications were body mass index ≥ 50, use of steroids, procedure type, predischarge complication, prolonged duration of stay, and prolonged operative time.

CONCLUSION

Postdischarge complications after bariatric surgery represent a substantial source of patient morbidity and hospital readmissions. The majority of postdischarge complications are infection-related, including surgical-site infections and catheter-associated urinary tract infections. Adopting and implementing standardized pre- and postoperative strategies to decrease perioperative infection may help to decrease the rate of postdischarge complications and associated readmissions and enhance overall quality of care.

Sleep apnea predicts distinct alterations in glucose homeostasis and biomarkers in obese adults with normal and impaired glucose metabolism

BACKGROUND

Notwithstanding previous studies supporting independent associations between obstructive sleep apnea (OSA) and prevalence of diabetes, the underlying pathogenesis of impaired glucose regulation in OSA remains unclear. We explored mechanisms linking OSA with prediabetes/diabetes and associated biomarker profiles. We hypothesized that OSA is associated with distinct alterations in glucose homeostasis and biomarker profiles in subjects with normal (NGM) and impaired glucose metabolism (IGM).

METHODS

Forty-five severely obese adults (36 women) without certain comorbidities/medications underwent anthropometric measurements, polysomnography, and blood tests. We measured fasting serum glucose, insulin, selected cytokines, and calculated homeostasis model assessment estimates of insulin sensitivity (HOMA-IS) and pancreatic beta-cell function (HOMA-B).

RESULTS

Both increases in apnea-hypopnea index (AHI) and the presence of prediabetes/diabetes were associated with reductions in HOMA-IS in the entire cohort even after adjustment for sex, race, age, and BMI (P = 0.003). In subjects with NGM (n = 30), OSA severity was associated with significantly increased HOMA-B (a trend towards decreased HOMA-IS) independent of sex and adiposity. OSA-related oxyhemoglobin desaturations correlated with TNF-α (r=-0.76; P = 0.001) in women with NGM and with IL-6 (rho=-0.55; P = 0.035) in women with IGM (n = 15) matched individually for age, adiposity, and AHI.

CONCLUSIONS

OSA is independently associated with altered glucose homeostasis and increased basal beta-cell function in severely obese adults with NGM. The findings suggest that moderate to severe OSA imposes an excessive functional demand on pancreatic beta-cells, which may lead to their exhaustion and impaired secretory capacity over time. The two distinct biomarker profiles linking sleep apnea with NGM and IGM via TNF-α and IL-6 have been discerned in our study to suggest that sleep apnea and particularly nocturnal oxyhemoglobin desaturations are associated with chronic metabolic fluxes and specific cytokine stressors that reflect links between sleep apnea and glucose metabolism. The study may help illuminate potential mechanisms for glucose dysregulation in OSA, and resolve some controversy over the associations of OSA with TNF-α and IL-6 in previous studies.

Transgastric ventral hernia repair: a controlled study in a live porcine model (with videos)

BACKGROUND

Ventral hernia repair is currently performed via open surgery or laparoscopic approach.

OBJECTIVE

To develop an alternative ventral hernia repair technique.

SETTING

Acute and survival experiments on twelve 50-kg pigs.

DESIGN AND INTERVENTIONS

An endoscope was introduced transgastrically into the peritoneal cavity. An abdominal wall hernia was created through a 5-mm skin incision followed by a 5-cm-long incision of the abdominal wall muscles and aponeurosis. A hernia repair technique was developed in 3 acute experiments. Then animals were randomized into 2 groups. In the experimental group (5 animals) Gore-Tex mesh was transgastrically attached to the abdominal wall, repairing the previously created abdominal wall hernia. In the control group (4 animals), the hernia was not repaired. In both groups, the endoscope was then withdrawn into the stomach, and the gastric wall incision was closed with T-bars. The animals survived for 2 weeks and were then euthanized.

MAIN OUTCOME MEASUREMENT

The presence of ventral hernia on necropsy.

RESULTS

In the control group, the ventral hernia was present on necropsy in all animals. In the experimental group, the ventral hernia was easily repaired, with no evidence of hernia on necropsy. In the first animal in the experimental group, necropsy revealed infected mesh. After this discovery, we used sterilized cover for mesh delivery and did not find any signs of infection in 4 subsequent study animals.

LIMITATION

The study was performed in a porcine model.

CONCLUSIONS

Transgastric ventral hernia repair is feasible, technically easy, and effective. It can become a less invasive alternative to the currently used laparoscopic and surgical ventral hernia repair.

Looking beyond age and co-morbidities as predictors of outcomes in paraesophageal hernia repair

INTRODUCTION

Paraesophageal hernia (PEH) repair is a technically challenging operation. These patients are typically older and have more co-morbidities than patients undergoing anti-reflux operations for gastroesophageal reflux disease (GERD), and these factors are usually cited as the reason for worse outcomes for PEH patients. Clinically, it would be useful to identify potentially modifiable variables leading to improved outcomes.

METHODS

We performed a retrospective analysis of a representative sample from 37 states, using the Nationwide Inpatient Sample database over a 5-year period (2001-2005). Patients undergoing any anti-reflux operation with or without hiatal hernia repair were included, and comparison was made based on primary diagnoses of PEH or GERD. Exclusion criteria were diagnosis codes not associated with reflux disease or diaphragmatic hernia, emergency admissions, and age <18. Primary outcome was in-hospital mortality. Two sets of multivariate analyses were performed; one set adjusting for pre-treatment variables (age, gender, race, Charlson Comorbidity Index, hospital teaching status, hospital volume of anti-reflux surgery, calendar year) and a second set adjusting further for post-operative complications (splenectomy, esophageal laceration, pneumothorax, hemorrhage, cardiac, pulmonary, and thromboembolic events, (VTE)).

RESULTS

Of the 23,458 patients, 6,706 patients had PEH. PEH patients are older (60.4 vs. 49.1, p < 0.001) and have significantly more co-morbidities than GERD patients. On multivariate analysis, adjusting for pre-treatment variables, PEH patients are more likely to die and have significantly worse outcomes than GERD patients. However, further adjustment for pulmonary complications, VTE, and hemorrhage eliminates the mortality difference between PEH and GERD patients, while adjustment for cardiac complications or pneumothorax did not eliminate the difference.

CONCLUSIONS

While PEH patients have worse post-operative outcomes than GERD patients, we note that differences in mortality are explained by pulmonary complications, VTE, and hemorrhage. The impact of hemorrhagic complications on this group underscores the importance of careful dissection. Additionally, age and co-morbidities alone should not preclude a patient from PEH repair; rather, attention should be focused on peri-operative optimization of pulmonary status and prophylaxis of thromboembolic events.

Dyslipidemia and atherosclerosis induced by chronic intermittent hypoxia are attenuated by deficiency of stearoyl coenzyme A desaturase

Obstructive sleep apnea leads to chronic intermittent hypoxia (CIH) and is associated with atherosclerosis. We have previously shown that C57BL/6J mice exposed to CIH and a high-cholesterol diet develop dyslipidemia, atherosclerosis of the aorta, and upregulation of a hepatic enzyme of lipoprotein secretion, stearoyl coenzyme A desaturase 1 (SCD-1). We hypothesized that (1) SCD-1 deficiency will prevent dyslipidemia and atherosclerosis during CIH; and (2) human OSA is associated with dyslipidemia and upregulation of hepatic SCD. C57BL/6J mice were exposed to CIH or normoxia for 10 weeks while being treated with either SCD-1 or control antisense oligonucleotides. Obese human subjects underwent sleep study and bariatric surgery with intraoperative liver biopsy. In mice, hypoxia increased hepatic SCD-1 and plasma very-low-density lipoprotein cholesterol levels and induced atherosclerosis lesions in the ascending aorta (the cross-section area of 156514+/-57408 microm(2)), and descending aorta (7.0+/-1.2% of the total aortic surface). In mice exposed to CIH and treated with SCD-1 antisense oligonucleotides, dyslipidemia and atherosclerosis in the ascending aorta were abolished, whereas lesions in the descending aorta showed 56% reduction. None of the mice exposed to normoxia developed atherosclerosis. In human subjects, hepatic SCD mRNA levels correlated with the degree of nocturnal hypoxemia (r=0.68, P=0.001). Patients exhibiting oxyhemoglobin desaturations at night showed higher plasma triglyceride and low-density lipoprotein cholesterol levels, compared to subjects without hypoxemia. In conclusion, CIH is associated with dyslipidemia and overexpression of hepatic SCD in both humans and mice alike; SCD-1 deficiency attenuates CIH-induced dyslipidemia and atherosclerosis in mice.

Flexible transgastric peritoneoscopy and liver biopsy: a feasibility study in human beings (with videos)

BACKGROUND

Multiple studies have demonstrated the feasibility of natural orifice transluminal endoscopic surgery in animal models.

OBJECTIVE

To determine the feasibility of transgastric peritoneoscopy and liver biopsy in human beings.

SETTING

Our institutional review board approved the procedures in the operating room with the patients under general anesthesia.

DESIGN AND INTERVENTIONS

During laparoscopic gastric bypass surgery a flexible endoscope was introduced into the peritoneal cavity through the gastric-wall incision. A peritoneoscopy with a liver biopsy was performed, then the flexible endoscope was withdrawn into the stomach, and gastric bypass surgery was completed laparoscopically.

PATIENTS

Three patients who were morbidly obese (mean weight 115.22 +/- 9.07 kg [254 +/- 20 lb]).

MAIN OUTCOME MEASUREMENTS

The ability to navigate a flexible endoscope inside the peritoneal cavity, to visualize the intra-abdominal organs, and to perform a liver biopsy without laparoscopic assistance.

RESULTS

It was very easy to navigate the flexible endoscope inside the abdomen by using torque, advancement, and withdrawal of the endoscopic shaft, as well as by movement of the endoscope tip. The flexible endoscope provided an excellent view and adequate illumination of the peritoneal cavity. The orientation of the flexible endoscope inside the peritoneal cavity was technically easy, even in the retroflex position. Systematic visualization of the liver, the spleen, the omentum, and the small and large intestine was easily achieved through the flexible endoscope without laparoscopic assistance. A liver biopsy was successfully completed in all cases by obtaining adequate tissue samples for histologic examination.

LIMITATION

This was a pilot feasibility study.

CONCLUSIONS

Transgastric flexible endoscopic peritoneoscopy in human beings is technically feasible, simple, and can become a valuable tool that complements and facilitates laparoscopic interventions inside the peritoneal cavity.

A zero leak rate in 251 consecutive laparoscopic gastric bypass operations using a two-layer gastrojejunostomy technique

PURPOSE

Laparoscopic Roux-en-Y gastric bypass is quickly replacing open techniques in the morbidly obese patient who presents for surgical treatment. Safety concerns about the laparoscopic technique have arisen in the literature with gastrojejunostomy leak rates of 5% or greater reported in several series.

MATERIALS AND METHODS

A total of 251 consecutive gastric bypass operations were performed from August 2001 to January 2004 by a single surgeon with over 6 years' experience. A double layer technique was used for every gastrojejunostomy anastomosis. This consisted of end-to-side stapled anastomosis using only 30 mm of a 45 mm blue (3.5 mm) staple cartridge that was fired inside the gastric pouch and Roux limb. A posterior running suture was then used to reinforce the back wall. An intraluminal 32F bougie was placed before the stapler opening was closed. Finally, 2 running sutures were used to reinforce the anterior and lateral sides of the anastomosis.

RESULTS

The average patient age was 43 years (range, 18-67 years), 89% were female, average preoperative weight was 137 kg (range, 89.5-214.5 kg), and average body mass index of 49 kg/m2 (range, 35-75). One hundred forty-two cases were performed with the Ethicon endoscopic linear stapler and 109 with the United States Surgical endoscopic linear stapler. There were no anastomotic leaks, staple line leaks, pulmonary emboli, or in-hospital deaths recorded. Endoscopic dilation successfully treated 10 (4%) cases of stomal stenosis. Eleven (4%) patients developed marginal ulcers that were easily treated with a proton pump inhibitor. Average excess weight loss at 12 months and 18 months was 63% and 71%, respectively.

CONCLUSIONS

Laparoscopic results are as good as or better than open surgery in the morbidly obese patient. The learning curve for this operation is steep and this may be reflected in the higher leak rates reported in earlier series. However, the technique used to create the gastrojejunostomy anastomosis may also account for a lower leak rate. The two-layer gastrojejunostomy anastomotic technique combines an inner stapled layer and outer sutured layer that yields excellent results.

An outcomes analysis of patients undergoing body contouring surgery after massive weight loss

BACKGROUND

Although published reports about technical management of massive weight loss patients are beginning to appear, risk factors for complications following body contouring operations are not known.

METHODS

A retrospective analysis of massive weight loss patients who had body contouring operations between March of 1998 and October of 2004 was performed. Demographic and surgical factors were analyzed. Outcome measures included seroma, wound dehiscence, thromboembolic complications, blood transfusion after surgery, and extended lengths of stay (>2 days).

RESULTS

A total of 139 patients were analyzed; 82.7 percent of them were female; mean age was 41 years. On multiple logistic regression, male gender was associated with significant risks for wound dehiscence (odds ratio, 6.4; p = 0.01). There were also trends toward increased risk for wound dehiscence with hypothyroidism (odds ratio, 4.3; p = 0.06) and Ehlers-Danlos syndrome (odds ratio, 18.7; p = 0.05). In terms of risk of blood transfusion, asthma and having three or more procedures were the two variables that emerged with significant association (odds ratio, 16.8 and 13.7, respectively; both p < 0.01). Increased length of stay to greater than 2 days was also significantly associated with having three or more procedures (odds ratio, 4.72; p < 0.01).

CONCLUSIONS

Male gender, hypothyroidism, and Ehlers-Danlos syndrome may be risk factors for wound dehiscence following body contour operations for massive weight loss. Asthma may be a marker of poor general health status, and asthmatic patients are at increased risk for requiring blood transfusions. Having three or more procedures is associated with an increased risk of blood transfusion and increased length of stay.

Insulin and its analogue glargine do not affect viability and proliferation of human coronary artery endothelial and smooth muscle cells

AIMS/HYPOTHESIS

Present guidelines for the treatment of type 2 diabetes recommend HbA1c values of less than 7%. As beta cell function worsens during progress of the disease, insulin therapy is often necessary to achieve this ambitious goal. However, due to peripheral insulin resistance, many patients need rather high insulin dosages. In the light of the extremely high cardiovascular risk of diabetic patients, it is important to determine whether high concentrations of insulin or its frequently used analogues are harmful to the cardiovascular system. We therefore investigated the modulatory effects of regular human insulin and its analogue glargine on proliferation and apoptosis of human coronary artery endothelial cells (HCAECs) and human coronary artery smooth muscle cells (HCASMCs).

METHODS

Cells were treated with regular human insulin or insulin glargine. Proliferation was determined by [3H]thymidine incorporation and by flow cytometric analysis of Ki-67 expression. Apoptosis was assessed by flow cytometry (cell cycle analysis and annexin V staining) and determination of caspase-3 activity.

RESULTS

HCAECs and HCASMCs treated with regular human insulin or insulin glargine did not show significant increases in DNA synthesis or Ki-67 expression. Administration of regular human insulin or insulin glargine did not modulate the extent of apoptotic events. No influence of insulin on lipoapoptotic vascular cell death could be detected.

CONCLUSIONS/INTERPRETATION

Taken together, neither regular human insulin nor insulin glargine influences growth and apoptosis of human coronary artery cells in vitro. Our data do not suggest that regular human insulin or insulin glargine promote atherosclerosis through mechanisms affecting the cellularity of human coronary arteries.

Hand-assisted laparoscopic gastric bypass does not improve outcome and increases costs when compared to open gastric bypass for the surgical treatment of obesity

BACKGROUND

Hand-assisted laparoscopic Roux-en-Y gastric bypass (Hand-Lap GB) has been adopted by some surgeons to treat morbid obesity because it is easier to perform than the total laparoscopic procedure, but to date no study has compared the outcomes of patients undergoing the Hand-Lap GB to those obtained with the open procedure (Open GB). We hypothesized that patients undergoing Hand-Lap GB would lose a similar amount of weight when compared to Open GB patients, while experiencing no increase in complications, a shorter hospital stay, and lower overall costs of care, in part as a result of fewer incisional hernias requiring subsequent surgery.

METHODS

Nonrandomized, prospective data were collected on all patients undergoing proximal GB via Hand-Lap or open approaches between May 1998 and July 1999. Our first 25 Hand-Lap GB procedures, performed in selected patients (with no extensive previous abdominal surgery) referred to two of us (E.J.D, M.A.S), were compared to all other (n = 62) concurrent open proximal GB performed by the group during this period of time in patients with body mass index (BMI) <50 kg/m2.

RESULTS

Preoperatively, Hand-Lap GB patients did not differ from Open GB patients in age (40 +/- 11 vs 43 +/- 11 years), gender (92% female vs 81% female), incidence or type of preoperative comorbid conditions, preoperative weight (282 +/- 33 vs 280 +/- 37 lb), or BMI (45.5 +/- 5.4 vs 44.1 +/- 3.3 kg/m2). (Data given as mean +/- standard deviation). Although length of hospital stay did not differ between groups (3.6 +/- 1.3 vs 4.2 +/- 4.6 days), total hospital costs were significantly higher for Hand-Lap GB ($14,725 +/- 3089 vs. $10,281 +/- 3687, p <0.01 ANOVA). One patient in the Open GB group developed an anastomotic leak from the gastrojejunostomy. Follow-up revealed that Hand-Lap GB patients had a similar risk of postoperative complications as the Open GB group, including marginal ulcer (16% vs 14.5%), stomal stenosis (24% vs 23%), and, most notably, incisional hernia (20% vs 27%). There were no major wound infections or deaths in either group. One patient in each group developed a postoperative small bowel obstruction. Loss of excess weight in Hand-Lap GB patients at 12 months postoperatively was 66 +/- 14% vs 77 +/- 14% in the Open GB group.

CONCLUSIONS

The Hand-Lap GB yielded good weight reduction in a population of morbidly obese patients, but at a higher cost for hospital care than Open GB. There was no decrease in the incidence of incisional hernias with the Hand-Lap GB procedure. Although Hand-Lap GB appears to be safe and effective, its failure to provide a decrease in hospital stay or risk of incisional hernia requiring subsequent surgical repair is significant. The primary role for the Hand-Lap GB procedure should therefore be to aid surgeons in developing skills to climb the steep learning curve for total laparoscopic gastric bypass, since Hand-Lap GB does not improve patient outcome and increases cost in comparison to the open GB procedure.

Risks and benefits of gastric bypass in morbidly obese patients with severe venous stasis disease

OBJECTIVE

To determine the risks and benefits of gastric bypass-induced weight loss on severe venous stasis disease in morbid obesity.

SUMMARY BACKGROUND DATA

Severe obesity is associated with a risk of lower extremity venous stasis disease, pretibial ulceration, cellulitis, and bronze edema.

METHODS

The GBP database was queried for venous stasis disease including pretibial venous stasis ulcers, bronze edema, and cellulitis.

RESULTS

Of 1,976 patients undergoing GBP, 64 (45% female) met the criteria. Mean age was 44 +/- 10 years. Thirty-seven patients had pretibial venous stasis ulcers, 4 had bronze edema, 23 had both, and 17 had recurrent cellulitis. All had 2 to 4+ pitting pretibial edema. Mean preoperative body mass index (BMI) was 61 +/- 12 kg/m(2) and weight was 179 +/- 39 kg (270 +/- 51% ideal body weight), significantly greater than in patients who underwent GBP without venous stasis disease. Two patients had a pulmonary embolus and four had Greenfield filters in the remote past. Additional comorbidities included obesity hypoventilation syndrome, sleep apnea syndrome, hypertension, gastroesophageal reflux, degenerative joint disease symptoms, type 2 diabetes mellitus, pseudotumor cerebri, and urinary incontinence. Comorbidities were significantly more frequent in the patients with venous stasis disease than for those without. At 3.9 +/- 4 years after surgery, patients lost 55 +/- 21 % of excess weight, 62 +/- 33 kg, reaching 40 +/- 9 kg/m(2) BMI or 176 +/- 41% ideal body weight. Venous stasis ulcers resolved in all but three patients. Complications included anastomotic leaks with peritonitis and death, fatal pulmonary embolism, fatal respiratory arrest, wound infections or seromas, staple line disruptions, marginal ulcerations treated with acid suppression, stomal stenoses treated with endoscopic dilatation, late small bowel obstructions, and incisional hernias. There were six other late deaths.

CONCLUSIONS

Severe venous stasis disease was associated with a significantly greater weight, BMI, male sex, age, comorbidity, and surgical risk (pulmonary embolus, leak, death, incisional hernia) than in other patients who underwent GBP. Surgically induced weight loss corrected the venous stasis disease in almost all patients as well as their other obesity-related problems.

Laparoscopic closure of mesenteric defects after Roux-en-Y gastric bypass

Two case reports are presented of incarcerated small-bowel internal hernias through mesenteric defects following Roux-en-Y gastric bypass surgery (one case each of open and laparoscopic). Both patients first presented to physicians unfamiliar with bariatric surgery complaining of vague, cramping midabdominal pain, and the correct diagnosis was not revealed until laparoscopic surgery was performed. Treatment then resulted in quick recoveries. This type of hernia can evade radiologic testing. Prompt clinical recognition and treatment is necessary to prevent small-bowel infarction.

Laparoscopic-assisted Roux-en-Y gastric bypass

Eight patients underwent laparoscopic Roux-en-Y gastric bypass from May 1998 to September 1998 in which a hand-assist technique was used. The operation consisted of a 7.5-cm periumbilical midline incision along with three trocars placed in the upper abdomen. The operative times ranged from 2.25 to 4.5 h. The average preoperative body mass index was 44 kg/m2. Three-month postoperative follow-up revealed an average weight loss of 59 lb. Cosmetic results to date have been excellent even when compared with those of a total laparoscopic operation. The hand-assist technique allows the surgeon to have more control over the most difficult part of the case, which is manipulation of the small bowel in a morbidly obese abdomen.

Pretreatment with allopurinol diminishes pancreatography-induced pancreatitis in a canine model

BACKGROUND

The role of oxygen-derived free radicals in the pathogenesis of pancreatitis has been supported by data from previous studies using animal models. This study was conducted to determine whether prophylaxis with the xanthine oxidase inhibitor allopurinol would decrease the incidence and severity of pancreatography-induced pancreatitis in a canine model.

METHODS

Thirty-two dogs were randomized to receive either placebo or oral allopurinol 1 hour before the procedure. A laparotomy and duodenotomy were performed and a pancreatogram was obtained. Postoperatively, pancreatic enzymes were drawn for 5 days. The animals were then euthanized, and the pancreas was weighed and evaluated histologically.

RESULTS

The histologic incidence of pancreatitis was significantly reduced in the allopurinol pretreatment group (6.7%) as compared with the placebo group (41.2%, p < 0.01). A significant decrease in postoperative serum amylase levels among dogs pretreated with allopurinol was also noted. A similar trend was observed in lipase levels. The pancreas weight index was decreased in the allopurinol pretreatment group as well (control = 0.00246 vs. allopurinol = 0.00195, p < 0.02).

CONCLUSIONS

Pretreatment with oral allopurinol decreases the incidence of pancreatography-induced pancreatitis. These results support the role of xanthine oxidase inhibitors in the prevention of endoscopic retrograde cholangiopancreatography-induced pancreatitis.

The clinical spectrum of Clostridium difficile colitis in immunocompromised patients

Clostridium difficile colitis is a nosocomial infection that continues to cause significant hospital morbidity despite adequate treatment. This morbidity may be especially costly in the immunocompromised patient who now makes up a greater percentage of hospitalized patients. The purpose of this study was to evaluate if patients in immunocompromised states are at risk for relapse of Clostridium difficile colitis, and to determine the efficacy of metronidazole in these patients. A retrospective chart review was conducted of patients with Clostridium difficile colitis over a 1-year period between 1990 and 1991. From this study group, 114 patients were identified who had both positive Clostridium difficile toxin assays of fecal specimens and documented in-house clinical infection. There were 67 immunocompromised patients (59%) in the study group. Oral vancomycin was given alone in 41 (36%) patients, metronidazole was used in 36 (32%) patients, and a combination was given in 15 (13%) patients. Twenty-two (19%) patients received no antibiotic therapy and had their preceding antibiotics terminated. Twelve (10.5%) patients had documented relapses, and all had an immunocompromising condition. There was no statistically significant difference in relapse rates between the vancomycin and metronidazole-treated patients. We conclude that metronidazole, with its significantly lower cost, should be used as first-line therapy in immunocompromised patients.