No difference in outcomes between large- and small-pore meshes in a prospective, randomized, multicenter trial investigating open retromuscular meshplasty for incisional hernia repair.

STUDY DESIGN: A randomized, controlled, prospective multicenter clinical trial with a parallel group design was initiated in eight surgical centers to compare a large-pore polypropylene mesh (Ultrapro®) to a small-pore polypropylene mesh (Premilene®) within a standardized retromuscular meshplasty for incisional hernia repair. METHODS: Between 2004 and 2006, patients with a fascial defect with a minimum diameter of 4 cm after vertical midline laparotomy were recruited for the trial. Patients underwent retromuscular meshplasty with either a large-pore or a small-pore mesh to identify the superiority of the large-pore mesh. Follow-up visits were scheduled at 5 and 21 days and 4, 12, and 24 months after surgery. A clinical examination, a modified short form 36 (SF-36®), a daily activity questionnaire, and an ultrasound investigation of the abdominal wall were completed at every follow-up visit. The primary outcome criterion was foreign body sensation at the 12-month visit, and the secondary endpoint criteria were the occurrence of hematoma, seroma, and chronic pain within 24 months postoperatively. RESULTS: In 8 centers, 181 patients were included in the study. Neither foreign body sensation within the first year after surgery (27.5% Ultrapro®, 32.2% Premilene®) nor the time until the first occurrence of foreign body sensation within the first year was significantly different between the groups. Regarding the secondary endpoints, no significant differences could be observed. At the 2-year follow-up, recurrences occurred in 5 Ultrapro® patients (5.5%) and 4 Premilene® patients (4.4%). CONCLUSION: Despite considerable differences in theoretical and experimental works, we have not been able to identify differences in surgical or patient-reported outcomes between the use of large- and small-pore meshes for retromuscular incisional hernia repair. TRIAL REGISTRATION: Clinical Trials NCT04961346 (16.06.2021) retrospectively registered.

Influence of suture technique on anastomotic leakage rate-a retrospective analyses comparing interrupted-versus continuous-sutures.

PURPOSE: While many hospitals consider a continuous sutured colonic anastomosis with monofilamental fiber the current state of the art, others have advocated for interrupted sutures as the gold standard. The aim of the study was to evaluate the influence of suture technique on leakage rate (primary endpoint), wound infections, postoperative stay, and mortality. METHODS: Retrospective analyses of 347 patients (273 elective, 74 urgent) over 6 years with a handsewn colonic anastomosis (190 interrupted, 157 continuous), excluding sigma and rectum anastomosis. Demographic and surgical baseline characteristics were used as competing predictors. RESULTS: Overall leakage rate was 9% but strongly dependent on suture technique (interrupted: 16%; continuous: 2.5%; p = 0.001) yielding an odds ratio of 5.10 [95% CI: 2.55, 6.71] (relative risk of leakage). No other variable showed a significant influence on leakage rate. Postoperative stay was prolonged in the interrupted suture group (23 ± 15 vs. 16 ± 11 days; p = 0.000, attributable effect 7.5 days [4.7, 10.3]). CONCLUSIONS: Our results indicate a highly significant reduction of anastomotic leakage rate and postoperative stay that generalize to the underlying population by continuous sutures in handsewn colonic anastomosis. In the absence of randomized prospective studies, the current results provide the yet strongest evidence for the superiority of continuous sutures.

Impact of body composition on survival and morbidity after liver resection in hepatocellular carcinoma patients.

BACKGROUND: Hepatocellular carcinoma is the most common innate liver tumor. Due to improved surgical techniques, even extended resections are feasible, and more patients can be treated with curative intent. As the liver is the central metabolic organ, preoperative metabolic assessment is crucial for risk stratification. Sarcopenia, obesity and sarcopenic obesity characterize body composition and metabolic status. Here we present the impact of body composition on survival after liver resection in patients with hepatocellular carcinoma. METHODS: A retrospective database analysis of 70 patients who were assigned for liver resection due to hepatocellular carcinoma was conducted. For assessment of sarcopenia and obesity, skeletal muscle surface area was measured at lumbar vertebra 3 level (L3) in preoperative four-phase contrast enhanced abdominal CT scans, and L3 muscle index and body fat percentage were calculated. RESULTS: Univariate analysis comparing the survival curves using the score test demonstrated superior postoperative overall survival for sarcopenic (P = 0.035) and sarcopenic obese (P = 0.048) patients as well as a trend favoring obese (P = 0.130) subjects. Whereas multivariate analysis could not identify significant difference in postoperative survival regarding sarcopenia, obesity or sarcopenic obesity. Only large tumor size, multifocal disease and male gender were risk factors for long-term survival. CONCLUSIONS: Sarcopenia, obesity and sarcopenic obesity are indeed no risk factors for poor postoperative survival in this study. Our data do not support the evaluation of sarcopenia, obesity and sarcopenic obesity before liver resection in hepatocellular carcinoma patients.

AK03, a new recombinant fibrinogenase prevents abdominal adhesions in a rat model without systemic side effects.

BACKGROUND: Abdominal adhesions are one of the most common complications after abdominal surgery, and fibrin is suspected to be a crucial component. The aim of the current study was an in vivo evaluation of a new recombinant fibrinogenase (AK03) in two animal models. METHODS: Sixty-four rats were randomly divided into four groups (sodium chloride [NaCl], icodextrin, AK03 low dose, and AK03 high dose) and evaluated at two time endpoints. Adhesion model comprised both a visceral defect (terminal ileum) and parietal defect. Test (AK03) and control substances (NaCl and icodextrin) were administered intraperitoneally after setting the intraabdominal defects. A second dose was administered 24 h after surgery. Plasma fibrinogen values were taken at baseline and after 7 and 21 d, respectively. Rats were sacrificed after 7 or 21 d for macroscopic (Diamond score) and immunohistochemical investigations. RESULTS: After 7 and 21 d, the Diamond score of postsurgical adhesions were significantly lower in both AK03-treated groups compared with NaCl control group (P = 0.02). There were no unspecific systemic side effects in both treatment groups and no decrease in plasma fibrinogen concentration. In none of the four groups was there any evidence for impaired wound repair. Microscopically in the area of the parietal defect, we saw less cluster of differentiation 3+ T-lymphocytes and cluster of differentiation 68+ macrophages in both groups receiving AK03 compared with the NaCl and icodextrin control groups. CONCLUSIONS: The results of this study indicate that the new recombinant fibrinogenase AK03 effectively prevents peritoneal adhesions without causing side effects, notably systemic fibrinogen depletion, bleeding, or impaired wound repair. Due to these results, future clinical studies may be promising.

Elevated levels of circulating osteopontin are associated with a poor survival after resection of cholangiocarcinoma.

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) represents a primary hepatic malignancy with incidence and mortality rising globally. Surgical treatment has remained the only potentially curative treatment option, but it is still unclear which patients benefit most from extended liver surgery, highlighting the need for new pre-operative stratification strategies. Osteopontin is a secreted extracellular glyco-phosphoprotein that has been associated with inflammation, metabolic disorders and cancer. Here, we examined the potential of circulating osteopontin serum levels as a diagnostic or prognostic biomarker in patients with CCA undergoing extended liver surgery. METHODS: Osteopontin expression levels were analysed in human and murine CCA tumour samples, using semi-quantitative reverse transcriptase PCR and immunohistochemistry. Osteopontin serum concentrations were measured by enzyme-linked immunosorbent assay in 107 patients with CCA undergoing elective tumour resection as well as 55 healthy controls. Results were correlated with clinical data. RESULTS: Correlating with an upregulation in CCA tumour cells and the tumour stroma, serum levels of osteopontin were elevated in patients with cholangiocarcinoma compared to healthy controls and patients with primary sclerosing cholangitis. Importantly, pre- and postoperative elevations of osteopontin showed a striking association with poor postoperative survival. CONCLUSIONS: Serum osteopontin concentrations represent a promising prognostic biomarker in patients resectable CCA which could help to guide preoperative treatment decisions and to identify patients that will particularly benefit from extended liver surgery. Lay summary: Extended liver surgery is the only potentially curative treatment for patients with cholangiocarcinoma (CCA/biliary cancer), but it is currently unclear which patients benefit most from surgery. Detecting serum levels of osteopontin - a specific secreted glycoprotein involved in multiple human diseases - in CCA patients might help to identify those patients that particularly benefit from tumour resection.

Sarcoidosis-Associated Aortoesophageal Fistula-Multistage Interdisciplinary Surgical Therapy for a Rare and Life-Threatening Condition.

Aortoesophageal fistulas (AEFs) are rare and life-threatening conditions. Till date, an association between an AEF and sarcoidosis has not been reported yet. The aim of this report is to demonstrate a case of AEF secondary to sarcoidosis and its multistage interdisciplinary surgical therapy. A 66-year-old male was diagnosed with sarcoidosis in 2014. He has been treated with glucocorticoids since then and no severe health restrictions due to the disease have occurred. In December 2015, the patient presented with acute thoracic pain and hematemesis: an esophagogastroscopy revealed an AEF. First, stent-graft implantation in the thoracic aorta was urgently performed as a "bridging" procedure. Second, esophagectomy and local debridement were performed, followed by explantation of the stent graft and reconstruction by means of xenograft replacement of the stented aorta in a third operation. Finally, retrosternal gastric pull-up was performed in a fourth operative procedure. Sixteen days after the last operation the patient could be discharged to a rehabilitation clinic. Follow-up is uneventful so far; the antibiotic therapy was stopped at the time of hospital discharge. The pathogenesis of sarcoidosis, a rare autoimmunological disease, has not been completely clarified yet. The diagnosis relies on clinical symptoms and radiological as well as histopathological findings. Many cases of sarcoidosis show spontaneous regression, but severe complications may occur. While tracheoesophageal fistulas have been described in the literature, AEFs related to sarcoidosis have not been mentioned yet. Despite surgical and antibiotic treatment, the morbidity and mortality rates of AEF are high. Because the endovascular treatment has been established for emergency procedures of the aorta, it is considered as an appropriate first-line "bridging" treatment option. To achieve good long-term results, surgical treatment has to involve esophagectomy with secondary reconstruction of the upper gastrointestinal tract, as well as open aortic replacement using xenograft or homograft material. Sarcoidosis may lead to AEF as demonstrated in this case. Successful treatment can be realized by a multistage interdisciplinary surgical approach.

A liver nodule in a patient transplanted for primary sclerosing cholangitis: an interdisciplinary diagnostic approach.

We report the case of a 53-year-old female patient who was transplanted with the liver of a 71-year-old male donor for advanced primary sclerosing cholangitis (PSC) and who additionally was diagnosed with a histologically non-classifiable colitis shortly before transplantation. Upon follow-up abdominal ultrasound 4 months after transplantation, a liver lesion measuring 16 × 23 mm was detected in the transplanted liver. This lesion had not been noticed immediately after transplantation and showed a pattern suspicious for malignancy in contrast-enhanced ultrasound. In line, a biopsy revealed the presence of a metastasis of an adenocarcinoma of colorectal origin, suggesting that a colitis- and PSC-associated colorectal cancer of the recipient might have been overseen upon the initial diagnostic workup. Despite two negative follow-up colonoscopies, this hypothesis was further supported by a strong positive signal in projection to the cecum in a subsequently performed PET/CT-scan. However, surgical resection of the right colon that was performed simultaneously with the atypical resection of the liver metastasis only revealed an inflamed diverticulum but no malignancy in the resected colon segment. Moreover, cytogenetic and molecular genetic testing on the resected specimens clearly attributed the metastasis to the male donor. On the one hand, this case underlines the necessity of endoscopic surveillance of patients with PSC and/or inflammatory bowel disease as well as the challenges in diagnosis of colitis-associated cancer. On the other hand, it shows that the acceptance of organs from elderly donors in times of organ shortage might be linked to an increased risk of donor transmitted malignancies.

Assessment of a course of realistic surgical training during medical education as a tool for pre-residential surgical training.

BACKGROUND: In recent years the focus on practical skills in the German curriculum of medical school has increased greatly. In this study we evaluate the value of a practical surgery course for medical students as a tool for surgical education, as a way of enhancing interest in surgical fields, and as a method of influencing medical students to subsequently choose a surgical career. METHODS: The "Feel like a surgeon"-course is an optional practical surgery course in which topographical anatomy and realistic surgical training using fresh human cadavers are combined for medical students of the RWTH Aachen University. Between 2010 and 2015 every student completed a survey before starting and after completing our course, and in 2015 a follow-up was performed. Using a standardized questionnaire, course quality, learning success and impact on post-instructional career and choice of profession was evaluated. RESULTS: In total, 82 students attended our course between 2010 and 2015 and took part in the evaluation. Evaluation of the course was positive overall, with an average grade of 1.4° ± °0.50. Significant improvement of basic, as well as more complex surgical skills and theoretical knowledge was noted. Furthermore, self-confidence for patient related assignments improved as well. In the follow-up evaluation, a high level of recommendation for surgical residents was seen, as was a high influence of the course on our students' career choice, although no significant change in career plans before and after taking the course was noted. CONCLUSIONS: Our results indicate that a practical surgical course can be a valuable tool to prepare students for a surgical residency and to improve their practical skills generally.

Influence of gentamicin-coded PVDF suture material on the healing of intestinal anastomosis in a rat model.

PURPOSE: Intestinal anastomosis is a fundamental procedure in general surgery and required to restore intestinal continuity following resection. The aim of this study was to evaluate whether a gentamicin-coated polyvinylidene fluoride (PVDF) suture material has beneficial effect on anastomotic healing. METHODS: Ninety Sprague-Dawley rats were divided into three groups: a PVDF-suture group, a gentamicin-coated PVDF (GPVDF)-suture group and a control group using Maxon® (polyglycolid-co-trimethylene carbonate). For each animal, a colonic anastomosis was performed. Ten animals from each group were sacrificed on postoperative days 3, 5, and 14. Measurements of anastomotic bursting pressure were performed on days 3 and 5. At each time, collagen type I/III ratio, MMP 2 and MMP-9 expression and the proliferation index (Ki67) were analyzed. RESULTS: In total, 90 animals underwent surgery without postoperative complications. Bursting strength in the GPVDF group was significantly elevated on day 5. Immunohistochemistry showed significant increase of the collagen type I/III ratio for PVDF and GPVDF on days 3 and 5. MMP2 was significantly increased for PVDF on days 3 and 5 and for GPVDF on day 5. The analysis of MMP9 revealed significant increase compared to control on day 3 and 5 (GPVDF) as well as on day 5 (PVDF). Staining for Ki67 revealed a significant elevation on postoperative day 3 for the PVDF and the GPVDF group. CONCLUSIONS: The present data shows the feasibility of PVDF as suture material for colonic anastomosis and confirms the ability of gentamicin to increase the stability of colonic anastomosis when used as coating material.

Vascular anatomy of the small intestine-a comparative anatomic study on humans and pigs.

BACKGROUND: Porcine models are well established for studying intestinal anastomotic healing. In this study, we aimed to clarify the anatomic differences between human and porcine small intestines. Additionally, we investigated the influences of longitudinal and circular sutures on human small intestine perfusion. METHODS: Intestines were obtained from human cadavers (n = 8; small intestine, n = 51) and from pigs (n = 10; small intestine, n = 60). Vascularization was visualized with mennige gelatin perfusion and high-resolution mammography. Endothelial cell density was analyzed with immunohistochemistry and factor VIII antibodies. We also investigated the influence of suture techniques (circular anastomoses, n = 19; longitudinal sutures, n = 15) on vascular perfusion. RESULTS: Only human samples showed branching of mesenteric vessels. Compared to the pig, human vessels showed closer connections at the entrance to the bowel wall (p = 0.045) and higher numbers of intramural anastomoses (p < 0.001). Porcine main vessels formed in multifilament-like vessel bundles and displayed few intramural vessel anastomoses. Circular anastomoses induced a circular perfusion defect at the bowel wall; longitudinal anastomoses induced significantly smaller perfusion defects (p < 0.001). Both species showed higher vascular density in the jejunum than in the ileum (p < 0.001). Human samples showed similar vascular density within the jejunum (p = 0.583) and higher density in the ileum (p < 0.001) compared to pig samples. CONCLUSION: The results showed significant differences between human and porcine intestines. The porcine model remains the standard for studies on anastomotic healing because it is currently the only viable model for studying anastomosis and wound healing. Nevertheless, scientific interpretations must consider the anatomic differences between humans and porcine intestines.

Polyvinylidene Fluoride as a Suture Material: Evaluation of Comet Tail-Like Infiltrate and Foreign Body Granuloma.

BACKGROUND: Biocompatibility and tissue integration of a surgical suture are decisive factors for wound healing and therefore for the success of sutures. The optimal suture material is still under discussion. Polyvinylidene fluoride (PVDF) is described to have superior properties of biocompatibility and is therefore frequently used as a mesh component. Only little information is available about its use as a suture material. The aim of this study was to evaluate the biocompatibility of PVDF as a suture material in comparison to 5 different established sutures in a rat model. METHODS: In 30 male rats, a monofilamental PVDF suture (Resopren®) and 5 established control suture materials [polyester (Miralene®), polytetrafluoroethylene (Gore®), poliglecaprone (Monocryl®), polydioxanone (Monoplus®), polyglactin 910 (Vicryl®), USP size 3-0] were placed in the subcutaneous layer of the abdominal wall without knot or tension. After 3, 7 or 21 days, the abdominal walls were explanted for histopathological and immunohistochemical investigation with special regard to the size and quality of foreign body granuloma and the length of the comet tail-like infiltrate (CTI). RESULTS: The PVDF sutures showed the smallest size of foreign body granuloma (60 ± 14 µm) and the smallest CTI length (343 ± 60 µm) of all polymers after 21 days. Only PVDF (Resopren) and polydioxanone (Monoplus) showed a significant collagen I/III ratio increase between days 3 and 21 (p = 0.009 and p = 0.016). The quality of foreign body reaction regarding inflammation, proliferation and fibrotic remodeling was similar between all suture materials. CONCLUSIONS: Our data indicate that monofilamental PVDF sutures show a favorable foreign body reaction with small granuloma sizes and CTI length in comparison to established sutures. Its use as a suture material in general surgery could therefore be extended in the future. To reinforce these findings, further clinical studies need to be conducted.

Video-assisted hepatic abscess debridement.

BACKGROUND: Pyogenic liver abscesses are currently treated by either percutaneous computer tomography (CT)-guided drainage or by laparoscopic and a conventional liver resection when conservative treatment fails but may be associated with substantial morbidity and mortality. METHODS: A minimally invasive technique involving debridement of right liver abscesses was employed using a minimally invasive video-assisted hepatic abscess debridement (VAHD) after unsuccessful percutaneous CT-guided drainage. Clinical data, complication rates and outcomes of patients were recorded retrospectively. RESULTS: Between 2011 and 2014, VAHD was performed on 10 patients at two centres with no observed recurrence of a liver abscess. The median age of the patients was 57 years (range 42-78) with a median pre-operative size of a liver abscess of 78 mm (range 40-115). The median operation time was 47 min (range 23-75), and the median postoperative hospital stay was 9 days (range 7-69). One patient developed a subcutaneous abscess that required further surgery. No patient died, and there were no major complications related to the VAHD. CONCLUSIONS: Video-assisted hepatic abscess debridement is a feasible technique that shows promising results for the treatment of a recurrent right liver abscess.

Influence of CD68+ macrophages and neutrophils on anastomotic healing following laparoscopic sigmoid resection due to diverticulitis.

BACKGROUND: The aim of this prospective study was to evaluate the predictive value of a potential preexisting low-grade inflammation regarding the incidence of anastomotic leakage in elective laparoscopic sigmoid resection due to diverticulitis. METHODS: Patients with either chronically recurrent diverticulitis or sigmoid stenosis caused by chronic diverticulitis were included in this study. All patients with acute local or systemic inflammation were excluded. Detailed patient information (e.g. American Society of Anesthesiologists (ASA) grade, comorbidities, duration of hospital stay, and anastomotic leakage) was prospectively recorded. CD68(+) macrophages, neutrophils, CD3(+) T-lymphocytes, CD11c(+) dendritic cells, MHCII, TNFR1, and NF-κB were evaluated by immunohistochemistry within the acquired sample of colonic bowel wall tissue. Clinical and immunohistochemical data was compared between groups (leakage vs. no leakage). Additionally, a matched-pair analysis was performed due to the widely heterogeneous groups concerning the number of patients and to minimize the effect of extraneous variables. RESULTS: A total of 83 patients were included in the study, of which 7 patients suffered an anastomotic leakage. Neither the clinical nor the immunohistochemical parameters were significantly different between the groups. The matched-pair analysis revealed a nonsignificant increase in mean duration of hospital stay for the group with anastomotic leakage and a significantly higher percentage of CD68(+) macrophages and neutrophils in the colonic wall obtained at the index operation in both the mucosal and submucosal layers for the leakage group. CONCLUSIONS: A preexisting low-grade inflammation represented by infiltrates of macrophages and neutrophils is a predictor for increased risk of developing colon anastomotic leakage.

Influence of 4% icodextrin solution on peritoneal tissue response and adhesion formation.

BACKGROUND: Postoperative peritoneal adhesion formation following abdominal surgery remains a relevant surgical problem. The application of soluble physico-chemical barriers like 4% icodextrin is one approach to protect the peritoneal surface from getting linked to adhesive scar. The aim of this study was to investigate the influence of 4% icodextrin on peritoneal tissue response both of visceral and parietal peritoneum, adhesion formation and wound healing. METHODS: 40 rats were divided into two groups. After creation of an intraabdominal defect, either 4% icodextrin (Adept®) or sodium chloride was applied. Animals were sacrificed after 7 and 21 days. Adhesions were scored by an adhesion score. Furthermore, immunohistochemical investigations were conducted to determine the discrete influence of icodextrin on the parietal and visceral peritoneal tissue responses (CD68+ macrophages, CD3+ T-lymphocytes, vimentin for mesenchymal cells, HBME-1 for mesothelial cells, and as components of wound healing COX-2, C-myc, catenin). RESULTS: Postoperative peritoneal adhesions were predominantly present in the sodium chloride group as compared to the icodextrin group (14/19 (74%) vs. 9/19 (47%); p = 0.048). The adhesion score however did not reveal any significant differences, (p = 0.614). Furthermore, the expression of vimentin in both the parietal and visceral peritoneum after 21 days was significantly lower in the icodextrin group than in the sodium chloride group (p = 0.038 and p = 0.028, respectively). No significant differences were observed for macrophages, lymphocytes, reperitonealisation or the expression of COX-2, C-myc or Catenin. CONCLUSIONS: The intraperitoneal application of 4% icodextrin reduces adhesion formation in comparison to sodium chloride. 4% icodextrin solution reduces the inflammatory and mesenchymal infiltrate in the wounded area, thus improving the ratio of mesothel cells to mesenchymal infiltrate. As demonstrated, icodextrin is able to ameliorate the local tissue response. Further experimental studies would be done to elaborate the impact on the early response of the adaptive immune system, which may then trigger the subsequent wound healing and tissue repair.

Mesh biocompatibility: effects of cellular inflammation and tissue remodelling.

Mesh biocompatibility is basically determined by the foreign body reaction (FBR). In contrast to physiological wound healing and scar formation, the FBR at the host-tissue/biomaterial interface is present for the lifetime of the medical device. The cellular interactions at the mesh/tissue interface proceed over time ending up in a chronic inflammatory process. The time course of the FBR has been studied extensively and consists of three crucial steps that are protein absorption, cell recruitment and, finally, fibrotic encapsulation and extracellular matrix formation. Each of these steps involves a complex cascade of immune modulators including soluble mediators and various cell types. Recent research has focused on the cellular and molecular interactions of the distinct phases of the FBR offering a new basis for therapeutical strategies. The highly dynamic process of the FBR is considerably influenced by the biomaterial composition. Modifications of the type of polymer, the material weight, the filament structure and the pore size are realized and have substantial effects on the in vivo biocompatibility. Moreover, modern mesh technology aims to utilize the available implants as carrier systems for bioactive drugs. Studies in animal models account for the efficiency of these drugs that aim to reduce mesh-related infections or to minimize FBR by influencing inflammation or extracellular matrix remodelling. A thorough understanding of the molecular mechanisms of FBR provides a sophisticated background for the development of new biomaterials at least as carrier systems for bioactive reagents to reduce inflammation and to improve clinical outcome.

Intrathoracic versus cervical anastomosis after resection of esophageal cancer: a matched pair analysis of 72 patients in a single center study.

BACKGROUND: The aim of this study was to analyze the early postoperative outcome of esophageal cancer treated by subtotal esophageal resection, gastric interposition and either intrathoracic or cervical anastomosis in a single center study. METHODS: 72 patients who received either a cervical or intrathoracic anastomosis after esophageal resection for esophageal cancer were matched by age and tumor stage. Collected data from these patients were analyzed retrospectively regarding morbidity and mortality rates. RESULTS: Anastomotic leakage rate was significantly lower in the intrathoracic anastomosis group than in the cervical anastomosis group (4 of 36 patients (11%) vs. 11 of 36 patients (31%); p = 0.040). The hospital stay was significantly shorter in the intrathoracic anastomosis group compared to the cervical anastomosis group (14 (range 10-110) vs. 26 days (range 12 - 105); p = 0.012). Wound infection and temporary paresis of the recurrent laryngeal nerve occurred significantly more often in the cervical anastomosis group compared to the intrathoracic anastomosis group (28% vs. 0%; p = 0.002 and 11% vs. 0%; p = 0.046). The overall In-hospital mortality rate was 6% (4 of 72 patients) without any differences between the study groups. CONCLUSIONS: The present data support the assumption that the transthoracic approach with an intrathoracic anastomosis compared to a cervical esophagogastrostomy is the safer and more beneficial procedure in patients with carcinoma of the lower and middle third of the esophagus due to a significant reduction of anastomotic leakage, wound infection, paresis of the recurrent laryngeal nerve and shorter hospital stay.

Gentamicin supplemented polyvinylidenfluoride mesh materials enhance tissue integration due to a transcriptionally reduced MMP-2 protein expression.

BACKGROUND: A beneficial effect of gentamicin supplemented mesh material on tissue integration is known. To further elucidate the interaction of collagen and MMP-2 in chronic foreign body reaction and to determine the significance of the MMP-2-specific regulatory element (RE-1) that is known to mediate 80% of the MMP-2 promoter activity, the spatial and temporal transcriptional regulation of the MMP-2 gene was analyzed at the cellular level. METHODS: A PVDF mesh material was surface modified by plasma-induced graft polymerization of acrylic acid (PVDF+PAAc). Three different gentamicin concentrations were bound to the provided active sites of the grafted mesh surfaces (2, 5 and 8 µg/mg). 75 male transgenic MMP-2/LacZ mice harbouring the LacZ reporter gene under control of MMP-2 regulatory sequence -1241/+423, excluding the RE-1 were randomized to five groups. Bilateral of the abdominal midline one of the five different meshes was implanted subcutaneously in each animal. MMP-2 gene transcription (anti-ß-galactosidase staining) and MMP-2 protein expression (anti-MMP-2 staining) were analyzed semiquantitatively by immunohistochemistry 7, 21 and 90 days after mesh implantation. The collagen type I/III ratio was analyzed by cross polarization microscopy to determine the quality of mesh integration. RESULTS: The perifilamentary ß-galactosidase expression as well as the collagen type I/III ratio increased up to the 90th day for all mesh modifications, whereas no significant changes could be observed for MMP-2 protein expression between days 21 and 90. Both the 5 and 8 µg/mg gentamicin group showed significantly reduced levels of ß-galactosidase expression and MMP-2 positive stained cells when compared to the PVDF group on day 7, 21 and 90 respectively (5 µg/mg: p < 0.05 each; 8 µg/mg: p < 0.05 each). Though the type I/III collagen ratio increased over time for all mesh modifications significant differences to the PVDF mesh were only detected for the 8 µg/mg group at all 3 time points (p < 0.05 each). CONCLUSIONS: Our current data indicate that lack of RE-1 is correlated with increased mesh induced MMP-2-gene expression for coated as well as for non-coated mesh materials. Gentamicin coating reduced MMP-2 transcription and protein expression. For the 8 µg/mg group this effect is associated with an increased type I/III collagen ratio. These findings suggest that gentamicin is beneficial for tissue integration after mesh implantation, which possibly is mediated via RE-1.

Using the Global Trigger Tool in surgical and neurosurgical patients: A feasibility study.

BACKGROUND: The Global Trigger Tool (GTT) has become a worldwide used method for estimating adverse events through a retrospective patient record review. However, little is known about the facilitators and the challenges in the GTT-implementation process. Thus, this study followed two aims: First, to apply a comprehensive set of feasibility criteria to qualitatively and systematically assess the GTT-implementation process in three departments of German university hospitals. Second, to identify the facilitators and the obstacles met in the GTT-implementation process and to derive recommendations for supporting other hospitals in implementing the GTT in clinical practice. METHODS: The study used a qualitative documentary method based on process documentation, with written and verbal feedback from the reviewer, as well as evaluating the study sites during the implementation process. The study was conducted in three departments, each in a different German university hospital. The authors applied a comprehensive set of 22 feasibility criteria assessing the level of challenge in GTT implementation. The results were synthesized and they focused on the facilitators and the challenges. RESULTS: Of these 22 feasibility criteria, nine were assessed as a low-level challenge, eleven regarded as a moderate-level challenge, and two with a problematic level of challenge. In particular, the lack of time and staff resources, the quality of the information in the patient records, organizational procedures, and local issues, posed major challenges in the implementation process. By contrast, the use of local coordinators and an external expert made important contributions to the GTT implementation. CONCLUSIONS: Considering the facilitators and the obstacles beforehand may help with the implementation of the GTT in routine practice. In particular, early and effective planning can reduce or prevent critical challenges in terms of time, staff resources, and organizational aspects.

Preoperative calcitonin testing improves the diagnosis of medullary thyroid carcinoma in female and male patients.

AIM: Calcitonin (Ctn) measurement in patients with thyroid disease could potentially increase the detection rates of medullary thyroid carcinoma (MTC) but remains a controversial issue. The aim of this study was to evaluate routine preoperative Ctn measurements. METHODS: All patients with thyroid surgery documented in the prospective StuDoQ|Thyroid registry between March 2017 and September 2020 were included. Cutoff levels for Ctn were determined with receiver-operating characteristic analyses to assess the preoperative diagnosis of MTC in subgroups for females and males. FINDINGS: In 29 590 of 39 679 patients (75%) participating in the registry, routine preoperative Ctn testing was performed. In 357 patients (227 females and 130 males), histopathology confirmed MTC with a mean tumor size of 14.7 mm (±12.43). Biochemical cure was achieved in 71.4% of the patients. Ctn levels between 11 and 20 pg/mL were seen in 2.6% of the patients, and only 0.7% of the patients had Ctn levels above 21 pg/mL. Cutoff levels for the diagnosis of MTC were 7.9 pg/mL for females and 15 pg/mL for males (P < 0.001). The sensitivity and specificity for females were 95 and 98%, and 96 and 97% for males, respectively. CONCLUSION: Routine Ctn testing is a reliable predictor for MTC and provides the opportunity for earlier thyroidectomy before lymph node metastases occur, resulting in a better prognosis. Females with Ctn levels >7.9 pg/mL and males >15 pg/mL without any other extrathyroidal sources for an elevated Ctn should be monitored. Thyroid surgery should be considered if Ctn levels are increasing or ultrasound detects suspicious thyroid lesions.

Balancing zinc deficiency leads to an improved healing of colon anastomosis in rats.

BACKGROUND: In colorectal surgery, anastomotic leakage is a relevant complication. The aim of this study was to investigate whether intraperitoneally (i.p.) administered zinc improves the healing of colon anastomosis in rats. MATERIALS AND METHODS: Male Wistar rats (66) received zinc-deficient diet for 21 days. To determine the effective dose of zinc which is necessary to compensate this deficiency, preliminary analysis in 30 rats were performed. In these rats, analysis by atom-absorption spectrophotometry revealed a dose of 1.0 mg zinc aspartate/kg body weight to be the compensatory dosage. In the remaining zinc-deficient rats (n= 36), a transverse colonic anastomosis was performed. Eighteen rats received either a zinc supplementation i.p. or 0.9% NaCl i.p. (n = 18; control group). On postoperative days 3, 5, and 14, the surface of the mucosal villi, expression of MMP 2, MMP 8, MMP 13, TIMP 1, as well as the collagen types I/III ratio were analyzed. RESULTS: Protein expression of MMP 2 and MMP 8 was significantly higher in the anastomosis of the zinc group on day 3 and on day 5. The collagen types I/III ratio was significantly increased in the zinc group on days 5 and 14. CONCLUSION: Balancing zinc deficiency benefits wound healing of colonic anastomosis qualitatively due to an increased collagen type I/III ratio. Surprisingly, these zinc supplements, however, increased the expression of MMP 2 and MMP 8 that are supposed to impair wound healing in case of an over-expression. Thus, further investigations are needed to elucidate the influence of zinc supplementation on regulation of MMPs.