Postpancreatectomy Acute Pancreatitis (PPAP): Definition and Grading From the International Study Group for Pancreatic Surgery (ISGPS).

OBJECTIVE: The ISGPS aimed to develop a universally accepted definition for PPAP for standardized reporting and outcome comparison. BACKGROUND: PPAP is an increasingly recognized complication after partial pancreatic resections, but its incidence and clinical impact, and even its existence are variable because an internationally accepted consensus definition and grading system are lacking. METHODS: The ISGPS developed a consensus definition and grading of PPAP with its members after an evidence review and after a series of discussions and multiple revisions from April 2020 to May 2021. RESULTS: We defined PPAP as an acute inflammatory condition of the pancreatic remnant beginning within the first 3 postoperative days after a partial pancreatic resection. The diagnosis requires (1) a sustained postoperative serum hyperamylasemia (POH) greater than the institutional upper limit of normal for at least the first 48 hours postoperatively, (2) associated with clinically relevant features, and (3) radiologic alterations consistent with PPAP. Three different PPAP grades were defined based on the clinical impact: (1) grade postoperative hyperamylasemia, biochemical changes only; (2) grade B, mild or moderate complications; and (3) grade C, severe life-threatening complications. DISCUSSIONS: The present definition and grading scale of PPAP, based on biochemical, radiologic, and clinical criteria, are instrumental for a better understanding of PPAP and the spectrum of postoperative complications related to this emerging entity. The current terminology will serve as a reference point for standard assessment and lend itself to developing specific treatments and prevention strategies.

An International Collaborative Study on Surgical Education for Quality Improvement (ASSURED): A Project by the 2017 International Society of Surgery (ISS/SIC) Travel Scholars International Working Group.

BACKGROUND: There is a huge difference in the standard of surgical training in different countries around the world. The disparity is more obvious in the various models of surgical training in low- and middle-income countries (LMICs) compared to high-income countries. Although the global training model of surgeons is evolving from an apprenticeship model to a competency-based model with additional training using simulation, the training of surgeons in LMICs still lacks a standard pathway of training. METHODS: This is a qualitative, descriptive, and collaborative study conducted in six LMICs across Asia, Africa, and South America. The data were collected on the status of surgical education in these countries as per the guidelines designed for the ASSURED project along with plans for quality improvement in surgical education in these countries. RESULTS: The training model in these selected LMICs appears to be a hybrid of the standard models of surgical training. The training models were tailored to the country's need, but many fail to meet international standards. There are many areas identified that can be addressed in order to improve the quality of surgical education in these countries. CONCLUSIONS: Many areas need to be improved for a better quality of surgical training in LMICs. There is a need of financial, technical, and research support for the improvement in these models of surgical education in LMICs.

Can We Accurately Identify Peritoneal Metastases Based on Their Appearance? An Assessment of the Current Practice of Intraoperative Gastrointestinal Cancer Staging.

BACKGROUND: Peritoneal lesions are common findings during operative abdominal cancer staging. The decision to perform biopsy is made subjectively by the surgeon, a practice the authors hypothesized to be imprecise. This study aimed to describe optical characteristics differentiating benign peritoneal lesions from peritoneal metastases. METHODS: The study evaluated laparoscopic images of 87 consecutive peritoneal lesions biopsied during staging laparoscopies for gastrointestinal malignancies from 2014 to 2017. A blinded survey assessing these lesions was completed by 10 oncologic surgeons. Three senior investigators categorized optical features of the lesions. Computer-aided digital image processing and machine learning was used to classify the lesions. RESULTS: Of the 87 lesions, 28 (32%) were metastases. On expert survey, surgeons on the average misidentified 36 ± 19% of metastases. Multivariate analysis identified degree of nodularity, border transition, and degree of transparency as independent predictors of metastases (each p < 0.03), with an area under the receiver operating characteristics curve (AUC) of 0.82 (95% confidence interval [CI], 0.72-0.91). Image processing demonstrated no difference using image color segmentation, but showed a difference in gradient magnitude between benign and metastatic lesions (AUC, 0.66; 95% CI 0.54-0.78; p = 0.02). Machine learning using a neural network with a tenfold cross-validation obtained an AUC of only 0.47. CONCLUSIONS: To date, neither experienced oncologic surgeons nor computerized image analysis can differentiate peritoneal metastases from benign peritoneal lesions with an accuracy that is clinically acceptable. Although certain features correlate with the presence of metastases, a substantial overlap in optical appearance exists between benign and metastatic peritoneal lesions. Therefore, this study suggested the need to perform biopsy for all peritoneal lesions during operative staging, or at least to lower the threshold significantly.

Recognition and Importance of New Definitions of Peripancreatic Fluid Collections in Managing Patients with Acute Pancreatitis.

Our understanding of the etiopathogenesis of acute pancreatitis has matured tremendously in the last 3 decades. Advanced cross-sectional imaging with 3-dimensional techniques along with use of intravenous contrast to image the presence or absence of organ tissue perfusion has allowed early recognition of necrotizing pancreatitis. With this knowledge, the old terms to describe what used to be called 'peri-pancreatic fluid collections' we now recognize are no longer accurate nor appropriate. The 2013 revised Atlanta Classification has introduced a new, accurate, objective classification of acute pancreatitis and terminology for the natural history of all forms of acute pancreatitis that is easy to use and will help in both the description of the disease and its appropriate treatment. This review will describe these pancreatic and peri-pancreatic collections with added insight into their natural history.

Kidney stones are common after bariatric surgery.

Obesity, a risk factor for kidney stones and chronic kidney disease (CKD), is effectively treated with bariatric surgery. However, it is unclear whether surgery alters stone or CKD risk. To determine this we studied 762 Olmsted County, Minnesota residents who underwent bariatric surgery and matched them with equally obese control individuals who did not undergo surgery. The majority of bariatric patients underwent standard Roux-en-Y gastric bypass (RYGB; 78%), with the remainder having more malabsorptive procedures (very long limb RYGB or biliopancreatic diversion/duodenal switch; 14%) or restrictive procedures (laparoscopic banding or sleeve gastrectomy; 7%). The mean age was 45 years with 80% being female. The mean preoperative body mass index (BMI) was 46.7 kg/m(2) for both cohorts. Rates of kidney stones were similar between surgery patients and controls at baseline, but new stone formation significantly increased in surgery patients (11.0%) compared with controls (4.3%) during 6.0 years of follow-up. After malabsorptive and standard surgery, the comorbidity-adjusted hazard ratio of incident stones was significantly increased to 4.15 and 2.13, respectively, but was not significantly changed for restrictive surgery. The risk of CKD significantly increased after the malabsorptive procedures (adjusted hazard ratio of 1.96). Thus, while RYGB and malabsorptive procedures are more effective for weight loss, both are associated with increased risk of stones, while malabsorptive procedures also increase CKD risk.

The art and science of publishing: reflections from editors of surgery journals.

During the 8th Annual Academic Surgical Congress held in New Orleans, Louisiana, on February 5-7, 2013, the Association for Academic Surgery (AAS) Presidential Session was dedicated to the topic of publishing. A survey consisting of 37 questions on issues related to publishing was administered to the AAS membership 1 mo before the meeting. The results of the survey were then presented during the 2013 AAS Presidential Session. In addition, a panel of five editors from surgery journals relevant to the membership of the AAS was convened to discuss topics addressed in the results of the survey. These topics included: (1) how to publish in high-impact factor journals; (2) top five reasons why manuscripts get rejected; (3) the do's and don'ts of publishing (i.e., ethics of publishing); (4) how to get on an editorial board; and (5) the future of publishing. This review summarizes the contents of this AAS Presidential Session and provides information relevant for any academician, investigator, or scientist.

Effect of reversible intermittent intra-abdominal vagal nerve blockade on morbid obesity: the ReCharge randomized clinical trial.

IMPORTANCE: Although conventional bariatric surgery results in weight loss, it does so with potential short-term and long-term morbidity. OBJECTIVE: To evaluate the effectiveness and safety of intermittent, reversible vagal nerve blockade therapy for obesity treatment. DESIGN, SETTING, AND PARTICIPANTS: A randomized, double-blind, sham-controlled clinical trial involving 239 participants who had a body mass index of 40 to 45 or 35 to 40 and 1 or more obesity-related condition was conducted at 10 sites in the United States and Australia between May and December 2011. The 12-month blinded portion of the 5-year study was completed in January 2013. INTERVENTIONS: One hundred sixty-two patients received an active vagal nerve block device and 77 received a sham device. All participants received weight management education. MAIN OUTCOMES AND MEASURES: The coprimary efficacy objectives were to determine whether the vagal nerve block was superior in mean percentage excess weight loss to sham by a 10-point margin with at least 55% of patients in the vagal block group achieving a 20% loss and 45% achieving a 25% loss. The primary safety objective was to determine whether the rate of serious adverse events related to device, procedure, or therapy in the vagal block group was less than 15%. RESULTS: In the intent-to-treat analysis, the vagal nerve block group had a mean 24.4% excess weight loss (9.2% of their initial body weight loss) vs 15.9% excess weight loss (6.0% initial body weight loss) in the sham group. The mean difference in the percentage of the excess weight loss between groups was 8.5 percentage points (95% CI, 3.1-13.9), which did not meet the 10-point target (P = .71), although weight loss was statistically greater in the vagal nerve block group (P = .002 for treatment difference in a post hoc analysis). At 12 months, 52% of patients in the vagal nerve block group achieved 20% or more excess weight loss and 38% achieved 25% or more excess weight loss vs 32% in the sham group who achieved 20% or more loss and 23% who achieved 25% or more loss. The device, procedure, or therapy-related serious adverse event rate in the vagal nerve block group was 3.7% (95% CI, 1.4%-7.9%), significantly lower than the 15% goal. The adverse events more frequent in the vagal nerve block group were heartburn or dyspepsia and abdominal pain attributed to therapy; all were reported as mild or moderate in severity. CONCLUSION AND RELEVANCE: Among patients with morbid obesity, the use of vagal nerve block therapy compared with a sham control device did not meet either of the prespecified coprimary efficacy objectives, although weight loss in the vagal block group was statistically greater than in the sham device group. The treatment was well tolerated, having met the primary safety objective. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01327976.

Classification of acute pancreatitis--2012: revision of the Atlanta classification and definitions by international consensus.

BACKGROUND AND OBJECTIVE: The Atlanta classification of acute pancreatitis enabled standardised reporting of research and aided communication between clinicians. Deficiencies identified and improved understanding of the disease make a revision necessary. METHODS: A web-based consultation was undertaken in 2007 to ensure wide participation of pancreatologists. After an initial meeting, the Working Group sent a draft document to 11 national and international pancreatic associations. This working draft was forwarded to all members. Revisions were made in response to comments, and the web-based consultation was repeated three times. The final consensus was reviewed, and only statements based on published evidence were retained. RESULTS: The revised classification of acute pancreatitis identified two phases of the disease: early and late. Severity is classified as mild, moderate or severe. Mild acute pancreatitis, the most common form, has no organ failure, local or systemic complications and usually resolves in the first week. Moderately severe acute pancreatitis is defined by the presence of transient organ failure, local complications or exacerbation of co-morbid disease. Severe acute pancreatitis is defined by persistent organ failure, that is, organ failure >48 h. Local complications are peripancreatic fluid collections, pancreatic and peripancreatic necrosis (sterile or infected), pseudocyst and walled-off necrosis (sterile or infected). We present a standardised template for reporting CT images. CONCLUSIONS: This international, web-based consensus provides clear definitions to classify acute pancreatitis using easily identified clinical and radiologic criteria. The wide consultation among pancreatologists to reach this consensus should encourage widespread adoption.

Prediction of pancreatic anastomotic failure after pancreatoduodenectomy: the use of preoperative, quantitative computed tomography to measure remnant pancreatic volume and body composition.

OBJECTIVE: To determine whether remnant pancreatic volume (RPV), subcutaneous/visceral adipose tissue(SAT/VAT) area, and skeletal muscle (SM) area calculated from preoperative computed tomography (CT) can predict the occurrence of pancreatic anastomotic failure (PAF) after pancreatoduodenectomy (PD). BACKGROUND: Increased body mass index, small main pancreatic duct, and soft pancreatic texture are well-established predictors of PAF after PD. The impact on PAF of anthropomorphic measurements, such as RPV and body composition, is unknown. METHODS: In 173 patients undergoing PD from 2004 to 2009, cross sections of SAT/VAT/SM area were quantitated volumetrically, respectively, from preoperative CT. RPV was calculated from the CT as the sum of pancreatic tissue area to the left of the presumed pancreatic transection site. The predictive ability for multiple models using combinations of body mass index, RPV, SAT/VAT area, SM area, main pancreatic duct size, and pancreatic gland texture was described using a concordance index (c-index). RESULTS: Clinically relevant PAF occurred in 22 patients (13%). Multivariate logistic regression analysis identified RPV (P = 0.0012), VAT area (P = 0.0003), and SM area (P = 0.0006) as independent predictors of PAF. Using previously identified risk factors, the best 2-predictor model (body mass index and pancreatic duct size) resulted in a c-index of 0.748. Using anthropomorphic factors, however, the 2-predictor model using VAT and SM areas revealed a superior c-index of 0.959. CONCLUSIONS: Our 2-predictor model using VAT area and SM area based on volumetric quantification using preoperative CT may offer clinical benefit as an objective prognostic measure to predict clinically relevant PAF after PD.

Survival is associated with genetic variation in inflammatory pathway genes among patients with resected and unresected pancreatic cancer.

OBJECTIVE: To test whether or not the association between inflammation and pancreatic ductal adenocarcinoma (PC) is facilitated by host susceptibility, specifically by genetic polymorphisms in inflammation-related genes. SUMMARY BACKGROUND DATA: Inflammation has been linked to PC. Reports have cited an increased expression of proinflammatory mediators, such as NF-κB and COX, in PC but not in normal adjacent tissue, suggesting a possible role in carcinogenesis. We sought to further understand the role that genetic variants in the NF-κB inflammatory pathway play in the development and progression of PC. METHODS: We genotyped 1536 tag single nucleotide polymorphisms (SNPs) in 102 candidate genes of multiple inflammatory pathways in 1308 white patients with PC who were divided into 3 groups on the basis of the extent of disease: resected for cure (n = 400), locally advanced/unresected (n = 443), and metastatic (n = 465). Survival analysis was performed using Kaplan-Meier curves and Cox proportional hazards regression models. Statistical significance was set at less than 0.001 to control for multiple testing. RESULTS: Median age was 67 (28.0-91.0) years, and 57% were men. Median survival for each of the 3 groups (resected, locally advanced, and metastatic) was 23.7, 9.4, and 6.6 months, respectively (P < 0.0001). In the resected group, carriers of a minor allele for either rs3824872 (MAPK8IP1) or rs8064821 (SOCS3) were associated with a 10- and 6-month survival advantage compared with noncarriers in patients with resected disease, with an additional 2-year survival if both minor alleles were present. With locally advanced disease, SNP rs1124736 (IGF1R) was associated with improved survival if they had a copy of the G allele, hazard ratio of 0.57 (95% confidence interval: 0.42-0.77); P = 0.0002. In addition, 4 SNPs in patients with metastatic disease were found to be associated with worse survival and 2 associated with improved overall survival, but the differences in survival were deemed not clinically significant. CONCLUSIONS: SNPs in the inflammatory pathway genes MAPK8IP1 and SOCS3 were associated with increased overall survival in patients undergoing potentially curative resection and may be used in the future as markers to predict survival. Future research is needed to determine the functional relevance of these loci.

Lack of functionally active sweet taste receptors in the jejunum in vivo in the rat.

BACKGROUND: When studied in enterocyte-like cell lines (Caco-2 and RIE cells), agonists and antagonists of the sweet taste receptor (STR) augment and decrease glucose uptake, respectively. We hypothesize that exposure to STR agonists and antagonists in vivo will augment glucose absorption in the rat. MATERIALS AND METHODS: About 30-cm segments of jejunum in anesthetized rats were perfused with iso-osmolar solutions containing 10, 35, and 100 mM glucose solutions (n = 6 rats, each group) with and without the STR agonist 2 mM acesulfame potassium and the STR inhibitor 10 µM U-73122 (inhibitor of the phospholipase C pathway). Carrier-mediated absorption of glucose was calculated by using stereospecific and nonstereospecific (14)C-d-glucose and (3)H-l-glucose, respectively. RESULTS: Addition of the STR agonist acesulfame potassium to the 10, 35, and 100 mM glucose solutions had no substantive effects on glucose absorption from 2.1 ± 0.2 to 2.0 ± 0.3, 5.8 ± 0.2 to 4.8 ± 0.2, and 15.5 ± 2.3 to 15.7 ± 2.7 µmoL/min/30-cm intestinal segment (P > 0.05), respectively. Addition of the STR inhibitor (U-73122) also had no effect on absorption in the 10, 35, and 100 mM solutions from 2.3 ± 0.1 to 2.1 ± 0.2, 7.7 ± 0.5 to 7.2 ± 0.5, and 15.7 ± 0.9 to 15.2 ± 1.1 µmoL/min/30-cm intestinal segment, respectively. CONCLUSIONS: Provision of glucose directly into rat jejunum does not augment glucose absorption via STR-mediated mechanisms within the jejunum in the rat. Our experiments show either no major role of STRs in mediating postprandial augmentation of glucose absorption or that proximal gastrointestinal tract stimulation of STR or other luminal factors may be required for absorption of glucose to be augmented by STR.

Roux-en-Y gastric bypass vs intensive medical management for the control of type 2 diabetes, hypertension, and hyperlipidemia: the Diabetes Surgery Study randomized clinical trial.

IMPORTANCE: Controlling glycemia, blood pressure, and cholesterol is important for patients with diabetes. How best to achieve this goal is unknown. OBJECTIVE: To compare Roux-en-Y gastric bypass with lifestyle and intensive medical management to achieve control of comorbid risk factors. DESIGN, SETTING, AND PARTICIPANTS: A 12-month, 2-group unblinded randomized trial at 4 teaching hospitals in the United States and Taiwan involving 120 participants who had a hemoglobin A1c (HbA1c) level of 8.0% or higher, body mass index (BMI) between 30.0 and 39.9, C peptide level of more than 1.0 ng/mL, and type 2 diabetes for at least 6 months. The study began in April 2008. INTERVENTIONS: Lifestyle-intensive medical management intervention and Roux-en-Y gastric bypass surgery. Medications for hyperglycemia, hypertension, and dyslipidemia were prescribed according to protocol and surgical techniques that were standardized. MAIN OUTCOMES AND MEASURES: Composite goal of HbA1c less than 7.0%, low-density lipoprotein cholesterol less than 100 mg/dL, and systolic blood pressure less than 130 mm Hg. RESULTS: All 120 patients received the intensive lifestyle-medical management protocol and 60 were randomly assigned to undergo Roux-en-Y gastric bypass. After 12-months, 28 participants (49%; 95% CI, 36%-63%) in the gastric bypass group and 11 (19%; 95% CI, 10%-32%) in the lifestyle-medical management group achieved the primary end points (odds ratio [OR], 4.8; 95% CI, 1.9-11.7). Participants in the gastric bypass group required 3.0 fewer medications (mean, 1.7 vs 4.8; 95% CI for the difference, 2.3-3.6) and lost 26.1% vs 7.9% of their initial body weigh compared with the lifestyle-medical management group (difference, 17.5%; 95% CI, 14.2%-20.7%). Regression analyses indicated that achieving the composite end point was primarily attributable to weight loss. There were 22 serious adverse events in the gastric bypass group, including 1 cardiovascular event, and 15 in the lifestyle-medical management group. There were 4 perioperative complications and 6 late postoperative complications. The gastric bypass group experienced more nutritional deficiency than the lifestyle-medical management group. CONCLUSIONS AND RELEVANCE: In mild to moderately obese patients with type 2 diabetes, adding gastric bypass surgery to lifestyle and medical management was associated with a greater likelihood of achieving the composite goal. Potential benefits of adding gastric bypass surgery to the best lifestyle and medical management strategies of diabetes must be weighed against the risk of serious adverse events. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00641251.

Safety and Efficacy of Revisional Surgery as a Treatment for Malnutrition after Bariatric Surgery.

BACKGROUND: Malnutrition after bariatric operation is a rare but potentially life-threatening complication. The safety and efficacy of revisional bariatric operation in malnourished patients are not well elucidated. STUDY DESIGN: We performed a retrospective chart review of patients who underwent revisional bariatric operation for severe malnutrition at our institution between 2008 and 2020. Associations of demographic and clinical characteristics with dichotomous outcomes of interest were examined using Fisher's exact tests, Cochran-Armitage tests for trend, and two-sample t -tests when appropriate. RESULTS: Fifty-three patients underwent revisional bariatric operation for malnutrition from 2008 and 2020. The median follow-up was 24 months. The anatomy before revision was Roux-en-Y gastric bypass (n = 40, 75%), biliopancreatic diversion with duodenal switch (n = 6, 11%), sleeve gastrectomy (n = 4, 8%), and mini gastric bypass (n = 3, 6%). The percentage of patients requiring supplemental or total nutritional support decreased from 89% preoperatively (47% on enteral feedings and 42% on total parenteral nutrition (TPN) with or without tube feeding) to 13.2% at the last encounter after revision (7.5% still requiring enteral feedings and 5.7% on TPN). There was an association between the number of prior abdominal operations and postoperative pneumonia (p 0.03) and need for blood transfusion (p 0.01). There were no associations between major complications or last encounter nutrition and any preoperative variables other than age at the time of operation. There were 2 mortalities during a median follow-up of 24 months, and both occurred more than 1 year postoperatively. CONCLUSION: Revisional operation for severely malnourished bariatric operation patients is effective in the discontinuation of supportive nutrition. Postoperative complications are increased but not prohibitive.

Hydrogen sulfide modulates contractile function in rat jejunum.

BACKGROUND: Effects of hydrogen sulfide (H(2)S), a third gasotransmitter of the gut, are not well understood. The aim of this study was to determine effects/mechanisms of H(2)S action on contractile function in rat jejunal muscle. METHODS: Transmural strips of longitudinal muscle were evaluated. Response to sodium hydrosulfide (NaHS, H(2)S donor; 10(-5)-10(-3)M) was studied on spontaneous contractile activity and after precontraction (bethanechol, 3 × 10(-6)M). Atropine, propranolol, phentolamine, tetrodotoxin, capsaicin, L-N(G)-nitro arginine (L-NNA), and glibenclamide were used to determine mechanisms. L-cysteine (10(-4)-10(-2)M; substrate for H(2)S production) and aminooxyacetic acid and DL-propargylglycine (inhibitors of enzymes generating H(2)S endogenously) were used to study endogenous production. Aminooxyacetic acid, DL-propargylglycine, L-NNA, and vasoactive intestinal polypeptide (VIP) antagonist [D-p-Cl-Phe(6),Leu(17)]-VIP were used to study H(2)S release during electrical field stimulation (EFS) and interaction with VIP and nitric oxide. Immunohistofluorescence of jejunal whole mounts was performed for endogenous H(2)S-producing enzymes. RESULTS: Cystathionine-ß-synthase and cystathionine-γ-lyase were expressed only in myenteric plexus. NaHS suppressed spontaneous and stimulated contractile activity (P < 0.01). Glibenclamide prevented some suppression by NaHS (P = 0.01) of stimulated contractile activity but did not prevent suppression of spontaneous contractile activity. Other drugs had no effect on spontaneous contractile activity but increased inhibitory effects of NaHS on spontaneous and stimulated contractile activity (P < 0.05). L-cysteine had no effects on contractile activity. Inhibitors altered basal and stimulated activity suggesting endogenous release of H(2)S. CONCLUSIONS: H(2)S presumably suppresses contractile activity in jejunum by direct effects on smooth muscle. Mechanism(s) of inhibition remains unclear, because blocking known neurotransmitters enhanced H(2)S-induced suppression, while blocking adenosine triphosphate (ATP)-sensitive K(+)-channels did not block H(2)S-induced inhibition.