Christophe Müller

Improving outcomes in hernia repair by the use of light meshes--a comparison of different implant constructions based on a critical appraisal of the literature.

BackgroundDespite convincing advantages offered by meshes, their use in hernia surgery remains controversial because of fears concerning the long-term effects of their implantation. To improve biocompatibility, a large variety of newly developed light meshes has been introduced to the market.This overview of the literature aimed to establish whether absolute material reduction (g per implanted mesh), use of absorbable components, and coating by inert materials are evidence-based ways to improve biocompatibility of meshes.MethodA review of the current English and German language literature on the outcome of groin und incisional hernia mesh repair was performed. Both basic research and clinical trials were used as sources of data. Meta-analyses and randomized controlled trials were given priority and were referred to whenever possible.ResultsOperative technique was an independent prognostic factor for the clinical outcome. Mesh construction and composition as characterized by pore size and filament structure appeared to be more important determinants of foreign body reaction after implantation than absolute material reduction of 1 g or more per implant. No data exist about an oncogenic effect of alloplastic materials in humans, but disturbed fertility in animal studies remains an issue of concern and should be further investigated.ConclusionsAccording to data from current randomized controlled trials and retrospective studies, light meshes seem to have some advantages with respect to postoperative pain and foreign body sensation. However, their use is associated with increased recurrence rates. Light meshes offer no advantages with respect to alleviating severe chronic groin pain. At the same time, experimental data reveal that material composition and mesh structure may significantly affect foreign body reaction.

Serum levels of procarboxypeptidase B and its activation peptide in patients with acute pancreatitis and non-pancreatic diseases

Background: Carboxypeptidase B from the pancreatic gland may exist in three different molecular and immunoreactive forms: the proenzyme, the active enzyme, and the activation peptide. Aims: To investigate levels of procarboxypeptidase B (proCAPB) and its activation peptide in serum in acute pancreatitis to test the accuracy of these two variables as markers for the diagnosis of acute pancreatitis and for prediction of pancreatic necrosis. To elucidate whether leakage of proenzymes and activation of proenzymes reflect two different pathophysiological events in acute pancreatitis. Methods: Sera from patients with acute pancreatitis (n=85) and acute abdominal pain of non-pancreatic origin (n=53) were analysed for proCAPB and its activation peptide. Patients with pancreatitis were divided into necrotising (n=33) and oedematous attacks (n=52) using contrast enhanced computed tomography. Accuracy was determined using receiver operating characteristic curve analysis. Results: Immunoreactive carboxypeptidase B activation peptide (ir-CAPAP) concentration in serum on admission was 0.7 nmol/l (0–18.1) in patients with oedematous pancreatitis compared with 5.8 nmol/l (1.9–34) in patients with later development of pancreatic necrosis. Elevated levels of the activation peptide on admission correlated with an accuracy of 92% to later development of pancreatic necrosis. Ir-proCAPB concentration in serum on admission was 16.0 nmol/l (1.4–50.5) in all patients with acute pancreatitis versus 0.3 nmol/l (0–3.6) in patients with non-pancreatic acute abdominal disorders. Cases with oedematous pancreatitis had ir-proCAPB levels of 15.4 nmol/l (1.4–50.5) versus 19.1 nmol/l (2.7–36.1) in cases with later development of pancreatic necrosis. Measurement of the proenzyme can thus be useful for the diagnosis of acute pancreatitis (accuracy 99%) but levels did not correlate with later development of pancreatic necrosis (accuracy 56%). Conclusion: Leakage of proenzymes occurs in acute pancreatitis, irrespective of severity, while development of pancreatic necrosis occurs only when there is activation of the proenzymes.

Neosphincter Surgery for Fecal Incontinence: A Critical and Unbiased Review of the Relevant Literature

Up until about 15 years ago the only realistic option for end-stage fecal incontinence was the creation of a permanent stoma. There have since been several developments. Dynamic graciloplasty (DGP) and artificial bowel sphincter (ABS) are well-established surgical techniques, which offer the patient a chance for continence restoration and improved quality of life; however, they are unfortunately associated with high morbidity and low success rates. Several trials have been done in an attempt to clarify the advantages and disadvantages of these methods and define their place in the second-line treatment of severe, refractory fecal incontinence. This review presents a critical and unbiased overview of the current status of neosphincter surgery according to the available data in the world literature.

Fecal incontinence: an up-to-date critical overview of surgical treatment options

BackgroundSurgery is the last resort for patients suffering from severe fecal incontinence. The armamentarium of surgical options for this condition has increased impressively during the last decade. Nevertheless, this fact seems to make neither patients nor surgeons feel more comfortable. Treatment of fecal incontinence still remains a challenge to modern medicine due to many specific sides of this problem.AimsThis article gives an up-to-date overview of existing operative treatment options.MethodsAn unbiased review of relevant literature was performed to assess the role of all methods of surgical treatment for fecal incontinence available nowadays.ResultsRecent studies have shown poor late results after primary sphincter repair and low predictive value for most preoperative diagnostic tests. New surgical options such as artificial devices and electrically stimulated muscle transpositions are doomed by low success rates and unacceptably frequent complications. That is why current attention has focused on non- or minimally invasive therapies such as sacral nerve stimulation and temperature-controlled radio-frequency energy delivery to the anal canal. However, all these innovative techniques remain experimental till enough high-evidence data are gathered for their objective evaluation.ConclusionCareful and detailed preoperative assessment to exactly determine the etiology of incontinence and individual approach remain the cornerstones of surgical treatment of fecal incontinence nowadays.

The role of TGF-β1 as a determinant of foreign body reaction to alloplastic materials in rat fibroblast cultures: comparison of different commercially available polypropylene meshes for hernia repair

BACKGROUND Animal experiments on hernia repair demonstrated better biocompatibility of light-weight polypropylene meshes. However, implanted medical devices trigger a variety of adverse tissue responses, such as inflammation, fibrosis, infection and thrombosis, but the mechanisms involved in such responses remain largely unknown. This study aimed to determine the effect of transforming growth factor beta1 (TGF-beta1) on host tolerance by quantification of foreign body reaction in cultured fibroblasts depending on the amount and composition of implanted material used for hernia repair. MATERIALS AND METHODS An NRK-49F fibroblast culture was incubated in the presence of 4 commercially available meshes approved for hernia repair. A mesh-free cell suspension served as a control group, in which the influence of TGF-beta1 on fibroblasts was evaluated. Levels of TGF-beta1 in the supernatant were dynamically measured in a time interval of 6 to 96 h and cell proliferation rates were assessed colorimetrically using MTT test. RESULTS A dose-dependent suppression of fibroblasts proliferation by TGF-beta1 was observed. All meshes suppressed the secretion of TGF-beta1 and conversely increased significantly cell proliferation in comparison to the control group (p<0.01) in the first 24 to 48 h of incubation. That effect was more pronounced in meshes partially containing absorbable material when compared to samples of pure polypropylene meshes (p<0.05) and to the control group (p<0.001). CONCLUSION Our experiment revealed that early biological reaction of connective tissue cells towards polypropylene meshes and their variants depended much more on the composition and type of the material than on its absolute amount. The assumption that material weight reduction alone might affect the foreign body reaction of mesh implants could not be confirmed by our in vitro study.

Protective role of endogenous melatonin in the early course of human acute pancreatitis

Abstract:  Melatonin plays a protective role in experimental acute pancreatitis (AP) because of its antioxidative, antiinflammatory, and immunomodulatory effects. This study presents the first data on the dynamic changes of endogenous melatonin in the early phase of human AP. Morning (08:00 hr) serum melatonin concentrations were measured by ELISA in 75 patients with AP for the first 5 days after the onset of pain. According to the Atlanta classification, 26 patients suffered a mild AP (MAP). The other 49 developed a severe AP (SAP). Median melatonin concentrations of healthy volunteers were used as a control. Median melatonin level in healthy controls was 18.5 pg/mL. Levels of melatonin were significantly higher in the first 24 hr after onset of disease in patients with MAP compared to those with SAP, 51.2 versus 8.7 pg/mL (P = 0.01). Melatonin values were the same in MAP and SAP during the remainder of the study period. Melatonin concentrations during the first 24 hr after the onset of pain in younger patients (<35 yrs old) were significantly higher than levels in older patients (>35 yrs): 73 versus 8.7 pg/mL (P = 0.01). No correlation existed between melatonin levels and the following parameters: gender, etiology (biliary versus alcohol induced), and histological findings (edematous versus necrotizing versus infected necrosis). High endogenous melatonin serum levels in the first 24 hr after the onset of AP played a protective role and favoured a mild course of the disease in humans, especially in young patients.

Dexamethasone affects inflammation but not trypsinogen activation in experimental acute pancreatitis.

Background/Aims: Trypsinogen activation and inflammation are early events in acute pancreatitis. This experimental study aimed to show the effects of dexamethasone on them. Methods: Cerulein and taurocholate pancreatitis were induced in 2 groups of 12 Wistar rats each. Six animals per group were injected with dexamethasone 1 h prior to the induction of acute pancreatitis. Amylase, phospholipase A2, TNF-α, IL-6, IL-10, α2-antiplasmin in plasma and trypsinogen activation peptide (TAP) in urine were measured in healthy rats, then 0.5 and 6 h after pancreatitis induction. A severity score based on edema, necrosis and ascites was calculated at 6 h. TNF-α, IL-6 and IL-10 were measured 0.5 h after laparotomy in a control sham-operated group of 6 rats. Results: Inflammatory markers increased early in the course of both mild and severe acute pancreatitis and were significantly lowered by dexamethasone. The severity score was higher in taurocholate than in cerulein pancreatitis. It was significantly decreased by dexamethasone only in rats with mild pancreatitis. TAP remained unchanged in mild pancreatitis compared to healthy animals but increased late in the course of taurocholate pancreatitis. Trypsinogen activation was not affected by dexamethasone at all. Conclusion: Inflammation occurred earlier than the increase in urinary TAP in severe pancreatitis in rats. Dexamethasone inhibited inflammation but had no influence on TAP levels in experimental mild and severe acute pancreatitis.

Double Sigmoid Colon Perforation by a Migrated Biliary Stent

Abstract The case of a female patient with a covered double perforation of the sigmoid colon is described. The perforation was due to a migrated plastic biliary stent inserted 3 weeks earlier for benign biliary obstruction and was facilitated by the presence of expressed diverticulosis of the colon. The lack of peritonitis and the early surgical procedure allowed a successful primary reconstruction after the colonic resection. Since the use of biliary stents is constantly increasing, such complications as stent migration and perforation should always be kept in mind by surgeons.

Corticosteroid-binding globulin: A possible early predictor of infection in acute necrotizing pancreatitis

Objective. Infected pancreatic necrosis is the main cause of death in patients with acute pancreatitis, and therefore its early prediction is of utmost importance. Endogenous cortisol metabolism plays a basic role both in the course of acute pancreatitis and in the process of infection. The purpose of this study was to analyze corticosteroid-binding globulin (CBG), total cortisol, calculated free cortisol and adrenocorticotropic hormone as potential early predictors in order to differentiate between infected pancreatic necrosis and sterile pancreatic necrosis in patients with acute pancreatitis. Material and methods. Serum levels of CBG, total cortisol, calculated free cortisol, and plasma levels of adrenocorticotropic hormone were determined in 109 consecutive patients with acute pancreatitis. C-reactive protein was measured as the control parameter. Thirty-five patients developed necrotizing pancreatitis and 10 developed infection of the necrosis. Blood was monitored for 6 days after the onset of pain; 30 healthy individuals served as controls. Results. Of all parameters only CBG showed a significant difference (p=0.0318) in its peak levels measured in the first 48 h in patients with sterile (26.5 µg/ml, range 21.3–34.7) and infected (16.0 µg/ml, range 15.2–25.0) necrosis at a cut-off level of 16.8 µg/ml. That difference was further preserved for the first 6 days after onset of pain. Conclusions. In our group of patients, a decreased CBG level below 16.8 µg/ml within the initial 48 h of acute pancreatitis was an early predictor of later infected pancreatic necrosis, with a positive predictive value of 100% and a negative predictive value of 87.5%.

Tailored resective pancreatic surgery for pediatric patients with chronic pancreatitis

BACKGROUND Surgical treatment for chronic pancreatitis (CP) in children comprises predominantly nonresective draining procedures. The purpose of this study was to identify indications, techniques, and results of organ-preserving resective pancreatic procedures for pediatric CP at our institution. PATIENTS AND METHODS A retrospective chart review was performed of all children undergoing pancreatic surgery for CP over a period of 4 years. RESULTS Overall, 6 pediatric patients (3 male, 3 female, ages 7-18 years) underwent a duodenum-preserving pancreatic head resection (3), a middle segmental pancreatic resection (2), or a distal pancreatectomy (1) for CP of different etiologies (idiopathic 2, posttraumatic 2, pancreas divisum 1, situs inversus 1). No mortality or major surgical complication occurred. Mean operative time was 294 min (207-412 min) and intraoperative blood loss was 541 mL (100-1300 mL). Postoperative hospital stay was 13 days (10-18 days). No endocrine or exocrine insufficiency occurred during follow up of 46 months (25-50 m), and pain control was improved in 5 of 6 patients. CONCLUSIONS Tailored organ-preserving resective pancreatic surgery can be performed with low morbidity and mortality in pediatric patients with CP and not responding to conservative treatment.