Effect of Intraoperative Blood Pressure Regulation on Postoperative Hemorrhage After Bariatric Surgery.

INTRODUCTION: With a rising number of bariatric procedures, the absolute number of postoperative complications is increasing, too. Postoperative bleeding, particularly along the staple line, is a recognized challenge. Numerous strategies including reinforcement of the staple line (SLR) have been proposed to improve bleeding rates, but no single technique has shown superiority over the others. In our bariatric center, we have implemented intraoperative blood pressure regulation alone, without SLR, to reduce hemorrhagic complications postoperatively. METHODS: This retrospective observational analysis compares the incidence of postoperative bleeding in two groups of consecutive patients (total n = 438 patients), one with and one without intraoperative blood pressure elevation to 150 mmHg systolic without the additional use of staple line reinforcement. This intervention was integrated into our standard bariatric surgical procedure, no randomization or matching was conducted. Significant postoperative bleeding was defined as drop of hemoglobin of more than 2.5 mg/dl in 48 h and one of the following symptoms: lactate ≥ 2 mmol/L, bloody drainage, quantity of drainage more than 200 ml and/or radiological signs. RESULTS: Defined postoperative bleeding occurred in 33 (7.5%) patients. We observed a decrease in bleeding rates from 10% to 5% (n = 22 vs. n = 11) after introducing intraoperative blood pressure increase (p = 0.034). The rate of revisional surgery for bleeding also decreased from 2.7% to 0.5% (n = 6 vs. n = 1). In multivariate analysis, the intervention with blood pressure elevation showed a significant decrease on bleeding rates (p = 0.038). CONCLUSION: The use of increased intraoperative blood pressure alone, without staple line reinforcement, appears to be an effective and suitable method for reducing post-bariatric hemorrhagic complications.

Banded Versus Non-banded Sleeve Gastrectomy: 5-Year Results of a 3-Year Randomized Controlled Trial.

PURPOSE: Banded sleeve gastrectomy (BSG) has been shown to enable better weight loss than non-banded sleeve gastrectomy (SG) in retrospective analyses. These findings were supported by two randomized controlled trials (RCT). However, to date, mid-term prospective data is not available. MATERIALS AND METHODS: We invited all 94 patients of an RCT comparing banded to non-banded sleeve gastrectomy at 3 years (DRKS00007729) for a 5-year follow-up visit. Eighty-two patients (BSG n = 42; SG n = 40) came for evaluation. Outcome measures were identical with the RCT to allow longitudinal comparison. Data analysis was descriptive and focused on biometric data, development of comorbidities, mid-term complications, quality of life, and type of body contouring surgery (BCS). RESULTS: The per-protocol analysis revealed a treatment difference of 9% (CI - 1.5 to 19.6) excess weight loss (EWL). Total weight loss (TWL) was 27.4% (CI 23.5-31.3) after SG and 31.6% (CI 27.3-35.5) after BSG. Twenty percent of patients after SG and 11.9% following BSG had been converted to a gastric bypass. Type 2 diabetes went into remission in most patients (SG 66.7% vs. BSG 63.6%). Antihypertensive medication was stopped or reduced in 81.3% after SG and 80% after BSG. Reflux symptoms were similar in both groups (symptoms [Formula: see text] 1/ week: SG 28.2% vs. BSG 26.8%). Frequency of postprandial regurgitation was higher after BSG (SG 23% vs. BSG 59%). Forty percent of patients had undergone BCS at time of follow-up. CONCLUSION: Five-year weight loss after BSG was 9% EWL and 4.2% TWL higher compared to SG. The main added morbidity following BSG was postprandial regurgitation.

Single-cell deconvolution reveals high lineage- and location-dependent heterogeneity in mesenchymal multivisceral stage 4 colorectal cancer.

Metastasized colorectal cancer (CRC) is associated with a poor prognosis and rapid disease progression. Besides hepatic metastasis, peritoneal carcinomatosis is the major cause of death in Union for International Cancer Control (UICC) stage IV CRC patients. Insights into differential site-specific reconstitution of tumor cells and the corresponding tumor microenvironment are still missing. Here, we analyzed the transcriptome of single cells derived from murine multivisceral CRC and delineated the intermetastatic cellular heterogeneity regarding tumor epithelium, stroma, and immune cells. Interestingly, we found an intercellular site-specific network of cancer-associated fibroblasts and tumor epithelium during peritoneal metastasis as well as an autologous feed-forward loop in cancer stem cells. We furthermore deciphered a metastatic dysfunctional adaptive immunity by a loss of B cell-dependent antigen presentation and consecutive effector T cell exhaustion. Furthermore, we demonstrated major similarities of this murine metastatic CRC model with human disease and - based on the results of our analysis - provided an auspicious site-specific immunomodulatory treatment approach for stage IV CRC by intraperitoneal checkpoint inhibition.

Senescent Tumor Cells in the Peritoneal Carcinomatosis Drive Immunosenescence in the Tumor Microenvironment.

More than half of all patients with colorectal cancer (CRC) develop distant metastasis and, depending on the local stage of the primary tumor, up to 48% of patients present peritoneal carcinomatosis (PC). PC is often considered as a widespread metastatic disease, which is almost resistant to current systemic therapies like chemotherapeutic and immunotherapeutic regimens. Here we could show that tumor cells of PC besides being senescent also exhibit stem cell features. To investigate these surprising findings in more detail, we established a murine model based on tumor organoids that resembles the clinical setting. In this murine orthotopic transplantation model for peritoneal carcinomatosis, we could show that the metastatic site in the peritoneum is responsible for senescence and stemness induction in tumor cells and that induction of senescence is not due to oncogene activation or therapy. In both mouse and human PC, senescence is associated with a senescence-associated secretory phenotype (SASP) influencing the tumor microenvironment (TME) of PC. SASP factors are able to induce a senescence phenotype in neighbouring cells. Here we could show that SASP leads to enhanced immunosenescence in the TME of PC. Our results provide a new immunoescape mechanism in PC explaining the resistance of PC to known chemo- and immunotherapeutic approaches. Therefore, senolytic approaches may represent a novel roadmap to target this terminal stage of CRC.

Long-Term Diabetes Improvement After Duodenal Exclusion in Zucker Diabetic Fatty Rats Is Associated with Prevention of Strain-Specific Pancreatic Remodeling and Increased Beta Cell Proliferation.

BACKGROUND: Response to metabolic surgery is heterogeneous and the metabolic states that underpin weight loss and metabolic improvement are still unclear. In this study, we investigate parameters of post-bariatric fasting glucoregulation and leverage artificial intelligence-assisted whole-slide image analyses to characterize associated immunohistologic features of the pancreas. MATERIALS AND METHODS: We performed either loop duodeno-jejunostomy (DJOS) with exclusion of 1/3 of total intestinal length, loop duodeno-ileostomy with exclusion of 2/3 of total intestinal length (DiOS), or a sham operation on 8-week-old male obese ZDF rats. Six months post-operative, we measured blood metabolites and hormones. Subsequently, pancreatic and intestinal tissue was removed, formalin fixed, and paraffin embedded. Immunohistologic (IHC) analyses included proliferating cell nuclear antigen (PCNA) to visualize the proliferation fraction and pancreatic and duodenal homeobox 1 (PDX 1) as a measure of pancreatic cell differentiation. For IHC quantification, all slides were digitalized and analyzed using QuPath. All analyzed slides were reviewed by two independent pathologists for correctness. RESULTS: DJOS and DiOS were associated with preserved fasting insulin production compared to sham. Histopathologic evaluation showed significantly higher numbers of beta cells and specifically of clustered cell organization in DJOS and DiOS compared to sham. Cell proliferation (PCNA) was significantly elevated in DJOS and DiOS compared to sham. CONCLUSION: In this interventional model of bariatric surgery in severe genetic diabetes, we demonstrate post-operative histologic and immunohistologic features of the pancreas associated with improved fasting glucose homeostasis.

Experiences and Short-Term Outcomes of Kidney Transplantation During the Coronavirus Disease 2019 Pandemic From a Medium-Volume Transplantation and Superregional Coronavirus Disease 2019 Treatment Center.

INTRODUCTION: The coronavirus, which first appeared in 2019, developed into a pandemic during 2020. It remains unclear to what extent the pandemic endangers the safety of kidney transplantation programs. In this study, we evaluated the short-term outcomes of our patients receiving a kidney transplant during the first phase and compared them with patients who received a kidney transplant immediately before the coronavirus pandemic. MATERIALS AND METHODS: Our retrospective study includes 34 kidney transplant recipients between October 1, 2019, and April 30, 2020. Nineteen patients from the phase immediately prior to the first coronavirus wave (pre-corona group), and 15 patients from the phase of the first coronavirus wave (corona group) were studied. We retrospectively evaluated demographic data, postoperative short-term outcomes and complications, immunosuppression regime, coronavirus infection status, and behavior during the first phase of the pandemic. RESULTS: There were no differences between the 2 groups regarding short-term outcomes and postoperative complications or in immunosuppressive medication. After the introduction of intensified hygienic conditions and routine swabs prior to transplantation, no nosocomial SARS-CoV-2 infections occurred. In the outpatient setting, none of the patients developed a SARS-CoV-2 infection. The majority of patients performed voluntary quarantine. CONCLUSIONS: The short-term outcomes after kidney transplantation during the first phase of the coronavirus pandemic were comparable to pre-pandemic patients, and no SARS-CoV-2-associated death or transplant failure occurred in our small cohort. We considered patient compliance with hygiene and self-isolation measures very high. Nevertheless, in further phases of the pandemic, the continuation of the living kidney donation program must be critically evaluated.

Banded Versus Nonbanded Sleeve Gastrectomy: A Randomized Controlled Trial With 3 Years of Follow-up.

OBJECTIVE: The aim of this study was to compare silicone-banded sleeve gastrectomy (BSG) to nonbanded sleeve gastrectomy (SG) regarding weight loss, obesity-related comorbidities, and complications. SUMMARY BACKGROUND DATA: As a primary bariatric procedure, SG leads to excellent weight loss, yet weight regain is a relevant issue in mid- to long-term follow-up. Retrospective analyses suggest that banding a sleeve using a silicone ring may decrease weight regain and improve weight loss. METHODS: The banded versus nonbanded sleeve gastrectomy single-center, randomized controlled trial was conducted from January 2015 to August 2019. The primary endpoint was defined as excess weight loss 3 years after surgery. Secondary endpoints included the surgery's impact on obesity-related comorbidities, quality of life, and complications. The study was registered under DRKS00007729. RESULTS: Among 94 patients randomized, 97% completed 3-year follow-up. Mean initial body mass index was 50.9 kg/m [95% confidence interval (CI), 49.6-52.2]. Mean adjusted excess weight loss 3 years after SG amounted to 62.3% (95% CI, 56.2-68.5) and 73.9% ( 95% CI, 67.8-80.0) after BSG (difference 11.6%, P = 0.0073). Remission of type 2 diabetes occurred in 66.7% (4/6) after SG and in 91.0% (10/11) following BSG (P = 0.21). Three years after surgery, ring implantation correlated with decreased frequency of symptomatic reflux episodes (P = 0.01) but increased frequency of regurgitation (P = 0.03). The rate of major complications was not different between the study groups (BSG, n = 3; SG, n = 2; P = 0.63). Quality of life was better following BSG (P = 0.001). CONCLUSIONS: BSG provided better weight loss than nonbanded SG 3 years after surgery. Regurgitation was the main clinically relevant negative effect after BSG.

Putting the Hindgut Hypothesis to the Test in a Diabetic Zucker Rat Model.

BACKGROUND: The hindgut theory hypothesizes a key role of differential hindgut stimulation following metabolic procedures in ameliorating diabetes mellitus. We used two strategies to remove the hindgut from intestinal continuity in order to analyze its impact on diabetes mellitus. METHODS: Loop duodeno-jejunostomy (DJOS) with exclusion of one-third of total intestinal length was performed in 3 groups of 9-week-old Zucker diabetic fatty rats. In group 1, no further alteration of the intestinal tract was made. Group 2 received additional ileal exclusion (IE). Group 3 underwent additional resection of 50% of the ileum with side-to-side ileocecal anastomosis (IR). One, 2, and 4 months after surgery, fasting blood glucose levels, oral glucose tolerance tests (OGTT), and glucose-stimulated hormone analyses were conducted, and bile acid blood levels were compared. Body weight was documented weekly. RESULTS: In relation to DJOS, glucose control was not impaired in IR or IE. On the contrary, only IR could maintain preOP glucose values until 4 months. There were no significant weight differences between the groups. Confirming effective ileal diversion, bile acid blood levels were significantly higher in the DJOS group compared with both IR and IE (p = 0.0025 and p = 0.0047). Operative interventions had no impact on GLP-1 levels at any time point (ANOVA p > 0.05 for all). Insulin secretion was preserved in all groups. CONCLUSION: This data supports the hypothesis that the mechanisms driving amelioration of diabetes mellitus are complex and cannot be reduced to the ileum.

Banded versus nonbanded sleeve gastrectomy: 5-year results of a matched-pair analysis.

BACKGROUND: Laparoscopic sleeve gastrectomy (SG) achieves excellent weight loss, yet recent reports indicate weight regain in a substantial number of patients. OBJECTIVES: Inserting a nonadjustable gastric band may improve weight loss after SG. SETTING: University Hospital, Germany. METHODS: In a retrospective matched-pair analysis 51 patients who underwent banded SG (BSG) using a silicone ring between November 2010 and May 2017 were compared with patients who underwent conventional SG regarding weight loss, complications, and co-morbidity. Median follow-up was 5 years. RESULTS: Total weight loss was equal in the early follow-up (P = .118 and P = .111) but significantly better in BSG 3 and 5 years after surgery (BSG versus SG at 3 yr 38.7% ± 7.8, n = 33 versus 31.9 ± 10.7, n = 33, P = .002; BSG versus SG at 5 yr 37.6% ± 8.5, n = 27 versus 29.5 ± 12.9, n = 23, P = .008). Ring placement had no significant impact on clinical reflux signs (Fisher's exact test P > .999), yet 37 % of BSG patients reported ≥1 regurgitation per week (Fisher's exact test P = .013, odds ratio 12.4). CONCLUSION: BSG leads to better weight loss than nonbanded SG 5 years after surgery. This comes at the expense of a higher rate of regurgitation. At a time in which weight loss limitations of a stand-alone SG are becoming a clinical problem, banding the sleeve may be a strategy to improve weight loss with this procedure.

The effect of pasireotide on intestinal anastomotic healing with and without whole-body irradiation in a rat model.

OBJECTIVE: To examine pasireotide's effect on intestinal anastomotic healing under physiological conditions and following preoperative whole-body irradiation. MATERIAL AND METHODS: Forty-five male Wistar rats received an ileoileal end-to-end anastomosis. Group 1 (Co, n = 9) served as control. Group 2 (SOM, n = 10) received pasireotide (60 mg/kg) 6 days preoperatively. Group 3 (R-Co, n = 13) was subjected to 8 Gy whole-body irradiation 4 days preoperatively. Finally, group 4 (R-SOM, n = 13) received pasireotide 6 days preoperatively and whole-body irradiation 4 days preoperatively. On postoperative day 4, anastomotic bursting pressure, histology, IGF-1 staining, and collagen density were examined. RESULTS: Mortality was higher in irradiated animals (30.8% vs. 5.3%, p = 0.021), and anastomotic bursting pressure was significantly lower (median, R-Co = 83 mmHg; R-SOM = 101 mmHg; Co = 149.5 mmHg; SOM = 169 mmHg). Inflammation measured by leukocyte infiltration following irradiation was reduced (p = 0.023), and less collagen was observed, though this was not statistically significant. Bursting pressure did not significantly differ between Co and SOM and between R-Co and R-SOM animals respectively. Semi-quantitative scoring of IGF-1, fibroblast bridging, or collagen density did not reveal significant differences among the groups. CONCLUSION: Whole-body irradiation decreases the quality of intestinal anastomotic wound healing and increases mortality. Pasireotide does not significantly lessen this detrimental effect.

Duodenal Exclusion but Not Sleeve Gastrectomy Preserves Insulin Secretion, Making It the More Effective Metabolic Procedure.

INTRODUCTION: There is an ongoing debate on which procedure provides the best treatment for type 2 diabetes. Furthermore, the pathomechanisms of diabetes improvement of partly anatomically differing operations is not fully understood. METHODS: A loop duodenojejunostomy (DJOS) with exclusion of one third of intestinal length, a sleeve gastrectomy (SG), or a combination of DJOS + SG was performed in 8-week-old male ZDF rats. One, three, and six months after surgery, an oral glucose tolerance test and measurements of GLP-1, GIP, insulin, and bile acids were conducted. RESULTS: After an initial (4 weeks) equal glucose control, DJOS and DJOS + SG showed significantly lower glucose levels than SG 3 and 6 months after surgery. There was sharp decline of insulin levels in SG animals over time, whereas insulin levels in DJOS and DJOS + SG were preserved. GIP levels were significantly larger in both groups containing a sleeve at all three time points, whereas GLP-1 was equal in all groups at all time. Bile acid levels were significantly higher in the DJOS compared to the SG group at all time points. Interestingly, the additional SG in the DJOS + SG group led to lower bile acid levels 1 and 6 months postoperatively. CONCLUSION: The effect of SG on glucose control was transient, whereas a duodenal exclusion was the more effective procedure in this model due to a sustained pancreatic function with a preserved insulin secretion.

Clinical Characteristics and Outcomes of Surgical Patients with Intensive Care Unit Lengths of Stay of 90 Days and Greater.

BACKGROUND: The aim of this study was to evaluate the influence of prolonged length of stay in an intensive care unit (ICU) on the mortality and morbidity of surgical patients. METHODS: We performed a monocentric and retrospective observational study in the surgical critical care unit of the department of surgery at the Medical Center of the University of Freiburg, Germany. Clinical data was collected from patients assigned to the ICU with a length of stay (LOS) of 90 days and greater. RESULTS: From the total of the 19 patients with ICU LOS over 90 days, ten patients died in the ICU whereas nine patients were discharged to the normal ward. The ICU mortality rate was 52%. The overall survival one year after ICU discharge was 32%. Regarding factors affecting mortality of the patients, significantly higher mortality was associated with age of the patients at the time point of the ICU admission and with postoperative need of renal replacement therapy. CONCLUSIONS: We found a high but in our opinion acceptable mortality rate in surgical patients with ICU LOS of 90 days and greater. We identified age and the need of renal replacement therapy as risk factors for mortality.

Common Channel Length in Bypass Surgery Does Not Impact T2DM in Diabetic Zucker Rats.

INTRODUCTION: Metabolic surgery is known to impact glucose tolerance but the exact mechanism is still unclear. Based on recently-published data, especially the role of the hindgut may require redefinition. METHODS: Either a loop duodeno-jejunostomy (DJOS) with exclusion of one third of total intestinal length, a loop duodeno-ileostomy (DiOS, exclusion of two thirds), or SHAM operation was performed in 9-week-old Zucker diabetic fatty rats. One, 3, and 6 months after surgery, an oral glucose tolerance test (OGTT) and glucose-stimulated hormone analyses were conducted. Body weight was documented weekly. RESULTS: DJOS and DiOS animals showed significantly better glucose control in all OGTTs than the SHAM group (two-way ANOVA p < 0.0001). Body weight developed largely parallel in both intervention groups; SHAM animals had gained significantly less weight after 6 months (Mann-Whitney DJOS/DiOS vs. SHAM p < 0.05, DJOS vs. DiOS p > 0.05). Operative interventions had no impact on GLP-1 and GIP levels at any time point (Mann-Whitney p > 0.05 for all). DJOS/DiOS operations could preserve insulin production up to 6 months, while there was already a sharp decline of insulin levels in the SHAM group (Mann-Whitney: DJOS/DiOS vs. SHAM p < 0.05 for all time points). Additionally, insulin sensitivity was improved significantly 1 month postoperative in both intervention groups compared to SHAM (Mann-Whitney DJOS/DiOS vs. SHAM p < 0.05). CONCLUSION: The data of the current study demonstrate a sharp amelioration of glucose control after duodenal exclusion with unchanged levels of GLP-1 and GIP. Direct or delayed hindgut stimulation had no impact on glucose control in our model.

Banding the Sleeve Improves Weight Loss in Midterm Follow-up.

INTRODUCTION: Laparoscopic sleeve gastrectomy (LSG) can achieve excellent weight loss, yet sleeve dilatation with concomitant weight regain proves to be a relevant issue. Hence, additional restriction might improve results after LSG. METHODS: In a retrospective matched-pair analysis, 42 patients who underwent banded LSG (BLSG) using a MiniMizer® ring between January 2012 and October 2014 were analysed regarding weight loss, complications and comorbidity. Median follow-up was 3 years. Forty-two patients who had undergone conventional LSG were selected as matched pairs. RESULTS: Mean preoperative BMI was 54.93 ± 7.42 kg/m2 for BLSG and 53.46 ± 6.69 kg/m2 for LSG (Mann-Whitney P = 0.540). Total weight loss (%TWL) was significantly greater in the BLSG group 3 years after surgery (BLSG 38.22% ± 7.26; n = 26 vs. LSG 32.69 ± 9.47; n = 26; P = 0.0154). Ring placement had no relevant impact on new-onset reflux (Fisher's exact test P = 1.0) but a tendency towards reflux improvement when reflux pre-existed (odds ratio 1.96). The major side effect of ring implantation was regurgitation with over 44% of patients presenting with regurgitation >1 per week (Fisher's exact test P = 0.0019, odds ratio 18.07). CONCLUSION: BLSG is a safe procedure showing similar comorbidity to conventional LSG. However, BLSG leads to a higher rate of postoperative regurgitation. Weight loss is significantly improved 3 years after surgery. Hence, additional ring implantation might be an option for increased restriction in LSG surgery.