V. Schumpelick

European Hernia Society guidelines on the treatment of inguinal hernia in adult patients

The European Hernia Society (EHS) is proud to present the EHS Guidelines for the Treatment of Inguinal Hernia in Adult Patients. The Guidelines contain recommendations for the treatment of inguinal hernia from diagnosis till aftercare. They have been developed by a Working Group consisting of expert surgeons with representatives of 14 country members of the EHS. They are evidence-based and, when necessary, a consensus was reached among all members. The Guidelines have been reviewed by a Steering Committee. Before finalisation, feedback from different national hernia societies was obtained. The Appraisal of Guidelines for REsearch and Evaluation (AGREE) instrument was used by the Cochrane Association to validate the Guidelines. The Guidelines can be used to adjust local protocols, for training purposes and quality control. They will be revised in 2012 in order to keep them updated. In between revisions, it is the intention of the Working Group to provide every year, during the EHS annual congress, a short update of new high-level evidence (randomised controlled trials [RCTs] and meta-analyses). Developing guidelines leads to questions that remain to be answered by specific research. Therefore, we provide recommendations for further research that can be performed to raise the level of evidence concerning certain aspects of inguinal hernia treatment. In addition, a short summary, specifically for the general practitioner, is given. In order to increase the practical use of the Guidelines by consultants and residents, more details on the most important surgical techniques, local infiltration anaesthesia and a patient information sheet is provided. The most important challenge now will be the implementation of the Guidelines in daily surgical practice. This remains an important task for the EHS. The establishment of an EHS school for teaching inguinal hernia repair surgical techniques, including tips and tricks from experts to overcome the learning curve (especially in endoscopic repair), will be the next step. Working together on this project was a great learning experience, and it was worthwhile and fun. Cultural differences between members were easily overcome by educating each other, respecting different views and always coming back to the principles of evidence-based medicine. The members of the Working Group would like to thank the EHS board for their support and especially Ethicon for sponsoring the many meetings that were needed to finalise such an ambitious project.

Foreign Body Reaction to Meshes Used for the Repair of Abdominal Wall Hernias

OBJECTIVE To investigate the local tissue reactions to meshes that had been removed from humans. DESIGN Open study SETTING Surgical department of the technical University, Aachen, Germany. MATERIAL Samples of 17 non-absorbable meshes (1 polyester, 10 polypropylene, 2 reduced polypropylene, and 4 polytetrafluorethylene, PTFE) and 1 absorbable mesh (polyglactin 910) that had been implanted for repair of abdominal wall defects. INTERVENTIONS Light and transmission electron microscopy, immunohistochemistry, and histological examination. MAIN OUTCOME MEASURES Signs of inflammatory response. RESULTS Light microscopy showed chronic inflammatory tissue reaction, even after years, with pronounced differences among materials. Partial volume of inflammatory cells (%) varied from 32 in polypropylene, to 12 in expanded PTFE, 8 in polyester, and 7 in reduced polypropylene. Formation of connective tissue correlated significantly with the extent of the inflammatory reaction (p<0.01). In meshes implanted for long periods there were still numerous macrophages at the interface between tissue and polypropylene (45%), polyester (45%), expanded PTFE (25%), and reduced polypropylene (22%). There was no difference in time dependent tissue reactions (p = 0.19). CONCLUSION Inflammation around alloplastic materials used to repair defects in the abdominal wall persists for many years. There was evidence of long term wound complications as a result of persistent foreign body reactions. Further studies are required to evaluate the long term tissue response to these materials.

Modified mesh for Hernia repair that is adapted to the physiology of the abdominal wall

OBJECTIVE To develop a new mesh for hernia repair that is adapted to the physiological forces. DESIGN Animal experiment. SETTING Surgical Department of the RWTH-Aachen. ANIMALS Wistar rats MAIN OUTCOME MEASURES Textile analysis, tensile strength, bending stiffness, histology and morphometry. RESULTS After textile analysis of commercially available meshes in clinical use we defined the physiological forces and constructed a new mesh (Soft Hernia Mesh, SHM) based on a combination of non-absorbable polypropylene and absorbable polyglactin 910. The amount of non-absorbable material could be reduced to < 30% compared with Marlex while still guaranteeing the necessary pulling force of 16 N/cm. Improvements of the hosiery structure improved the symmetrical distribution of the retaining forces in all directions. Compared with the considerable restriction of the abdominal wall mobility by Prolene (polypropylene) and Mersilene (polyester) meshes there was no increase in the bending stiffness after the implantation of the new mesh. Histological examination showed a pronounced reduction of the inflammatory reaction in the tissues, and the collagen bundles were orientated merely around the mesh filaments instead of forming a scar plate that completely embedded the mesh. CONCLUSION Different meshes caused specific histological reactions with changes of their mechanical properties after implantation in rodents. A new mesh with a reduced amount of polypropylene showed both less inflammation and less restriction in the mobility of the abdominal wall though it exceeded the required tensile strength of 16 N/cm.

Shrinking of Polypropylene Mesh in vivo: An Experimental Study in Dogs

OBJECTIVE To assess the extent of shrinkage of meshes used for hernia repair. DESIGN Experimental study in dogs. SETTING University hospital, Germany and University Research Centre, Moscow. ANIMALS 10 dogs had monofilament polypropylene meshes that weighed 95 g/m2 (Marlex) or multifilament reduced polypropylene meshes combined with polyglactin 910 that weighed 55 g/m2 (Soft Hernia Mesh) implanted for either 3 or 6 months. MAIN OUTCOME MEASURES Histological appearance and radiological assessment of the position and area of the mesh. RESULTS After 4 weeks the area of mesh in the monofilament group was reduced from to 139 (11) to 75 (8) cm2 (54%) and that of the multifilament from 116 (18) to 77 (20) cm2 (66%). The multifilament mesh with the reduced amount of polypropylene showed less inflammatory response and less shrinkage. The mesh did not seem to have moved. CONCLUSION Meshes that contain a lot of polypropylene shrink to about 30%-50% of their original size after 4 weeks, requiring an overlap of at least 3 cm if implanted subfascially. Reduction in the polypropylene content decreases both the inflammatory response and the shrinkage. Meshes with big pores are less likely to fold and improve compatibility.

Fluorine-18 fluorodeoxyglucose positron emission tomography in the differential diagnosis of pancreatic carcinoma: a report of 106 cases

The aim of this study was to evaluate fluorine-18 fluorodeoxyglucose positron emission tomography ([18F]FDG PET) as a tool for the differential diagnosis of pancreatic carcinoma while taking into account serum glucose level. A group of 106 patients with unclear pancreatic masses were recruited for the study. PET was performed following intravenous administration of an average of 190 MBq [18F]FDG. Focally increased glucose utilisation was used as the criterion of malignancy. In addition, the \ldstandardised uptake value\rd (SUV) was determined 45 min after injection. Carcinoma of the pancreas was demonstrated histologically in 74 cases, and chronic pancreatitis in 32 cases. Employing visual evaluation, 63 of the 74 (85%) pancreatic carcinomas were identified by PET. In 27 of the 32 cases (84%) of chronic pancreatitis il was possible to exclude malignancy. False-negative results (n=11) were obtained mostly in patients with raised serum glucose levels (10 out of 11), and false-positives (n=5) in patients with inflammatory processes of the pancreas. Thus PET showed an overall sensitivity of 85%, a specificity of 84%, a negative predictive value of 71%, and a positive predictive value of 93%. In a subgroup of patients with normal serum glucose levels (n=72), the results were 98%, 84%, 96% and 93%, respectively. Quantitative assessment yielded a mean SUV of 6.4\+-3.6 for pancreatic carcinoma as against a value of 3.6\+-1.7 for chronic pancreatitis (P\s<0.001), without increasing the diagnostic accuracy. This shows PET to be of value in assessing unclear pancreatic masses. The diagnostic accuracy of PET examinations is very dependent on serum glucose levels.

Functional and morphological evaluation of different polypropylene-mesh modifications for abdominal wall repair.

Modern surgical hernia repair depends increasingly on synthetic meshes for the reconstruction of the abdominal wall. Despite the undisputed advantages of the polypropylene (PP) meshes currently available (Marlex, Prolene), reports of complications after implantation are increasing. Although, serious complications such as perforation and fistula formation are rare, minor and local complaints such as seromas, misfeelings and a decreased abdominal wall mobility are observed in about one-half of the patients. In regard to the exaggerated strength of the currently available mesh modifications a reduction of the material should improve the integration of the meshes into the artificial abdominal wall. In the present study, the commercially available basic mesh Prolene has been compared to two newly constructed PP-mesh modifications with reduced amounts of PP. The modifications have gradually been adopted to the physiological requirements of abdominal wall stability and mobility by reducing the amount of PP to 64% (E-BLUE) and 24% (variant A) of the Prolene mesh (developed by ETHICON, Norderstedt, Germany). All PP-mesh variants have been implanted in a rat model and studied by 3D-photogrammetry, tensiometry, light- and electron microscopy, as well as morphometry over implantation intervals of 3, 7, 14, 21 and 90 days. The data show that current constructions of PP-meshes are oversized and definitely restrict abdominal wall mobility in the present model. Sufficient stability of the artificial abdominal wall is even guaranteed by PP-mesh modifications with a reduction of PP-quantity to about 25% of the Prolene mesh. The degree of fibrosis directly correlated with abdominal wall restriction, whereas the formation of connective tissue in the interface PP-fibre/host-issue depends on the amount and activity of the inflammatory reaction. The quantity and quality of inflammation, again, directly relies to the amount of PP and to the surface area in contact with the recipient tissues. Altogether, the present study suggests that a modification of the PP-meshes could be helpful to prevent major and minor complications of surgical PP-meshes.

Einflussfaktoren der Narbenhernienentstehung Retrospektive Untersuchung an 2.983 laparotomierten Patienten über einen Zeitraum von 10 Jahren

AbstractIntroduction. Incisional hernia formation is one of the most frequent complications in visceral surgery requiring reoperation. Risk factors for incisional hernia formation and preventive strategies are not clearly defined. Methods. In a retrospective study including 2983 patients over a 10-year period, the influence of demographic data, pre-, intra- and postoperative risk factors for incisional hernia development were evaluated. From the subgroups medical history, medication, laboratory values, indication, surgical technique, course of operation, postoperative course and wound healing, altogether 43 parameters were analysed. Statistical evaluation was performed using the χ2-test according to Pearson, and binary logistic regression analysis. Results. The mean incisional hernia incidence in the study was 4.3%. In the mean follow-up period of 21.1 months, the incisional hernia incidence was calculated at 9.8% using the Kaplan-Meier estimate; for a 10-year period it reached 18.7%. The study revealed that 31.5% of all incisional hernias developed in the first 6 months after the operation, 54.4% after 12 months, 74.8% after 2 years and 88.9% after 5 years. Significant demographic factors influencing incisional hernia incidence were age (>45 years) and male gender. The preoperative factors anaemia (Hb<100 g/l) and BMI >25, the intraoperative factors recurrent incision and previous laparotomy, and the postoperative factors catecholamin-therapy and disturbed wound healing were of significant influence. Conclusion. The calculated incisional hernia incidence for a 10 year period of almost 20% and the manifestation of 50% of all hernias more than 12 months after the operation, underline the necessity to intensify surgical research in the field of laparotomy healing. In comparison to demographic and endogenous risk factors, the surgical technique has less influence on laparotomy healing. Measures to ameliorate tissue perfusion seem to exert a positive influence on incisional hernia incidence.ZusammenfassungEinleitung. Die Narbenhernienentwicklung stellt eine der häufigsten operationspflichtigen Komplikationen in der Viszeralchirurgie dar. Die Risikofaktoren für die Narbenhernienentstehung und Strategien zu ihrer Vermeidung sind umstritten. Methoden. In einer retrospektiven Untersuchung an 2.983 Patienten über einen Zeitraum von 10 Jahren wurde der Einfluss demographischer Daten sowie von prä-, intra- und postoperativen Risikofaktoren auf die Narbenhernienentstehung untersucht. Aus den Untergruppen Vorerkrankungen, Medikation, Laborparameter, Indikation, Operationstechnik, Operationsverlauf, postoperativer Verlauf und Wundheilung wurden 43 Parameter untersucht. Die statistische Analyse erfolgte mit dem χ2-Test nach Pearson sowie multivariat mit der binär logistischen Regression. Ergebnisse. Die mittlere Narbenhernieninzidenz betrug 4,3%. Für den durchschnittlichen Beobachtungszeitraum von 21,1 Monaten lag die nach Kaplan-Meier berechnete Narbenhernieninzidenz bei 9,8%, für einen Zeitraum von 10 Jahren bei 18,7%. In den ersten 6 Monaten entstanden 31,5% der Narbenhernien, 54,3% der Narbenhernien manifestierten sich nach 1 Jahr, 74.8% nach 2 und 88,9% nach 5 Jahren. Als signifikante demographische Faktoren für die Narbenhernieninzidenz fanden sich Lebensalter (>45 Jahre) und männliches Geschlecht. Die präoperativen Faktoren Anämie (Hb<100 g/) und Adipositas (BMI >25), die intraoperativen Faktoren Rezidivinzision, Voroperationen sowie die postoperativen Faktoren Katecholamintherapie und Wundkomplikationen hatten ebenfalls signifikanten Einfluss bei der univariaten Analyse. Schlussfolgerung. Die zu erwartende Narbenhernieninzidenz von fast 20% bei langer Nachbeobachtungszeit sowie die Manifestation von 50% der Narbenhernien mehr als 1 Jahr postoperativ unterstreichen die Notwendigkeit, der Laparotomieheilung mehr Beachtung zu schenken. Hinter demographischen und endogenen Risikofaktoren treten operativ-technische Faktoren als Auslöser der Narbenhernienentstehung in den Hintergrund. Mit vertretbarem Aufwand scheinen Maßnahmen zur Verbesserung der Gewebeperfusion geeignet, die Narbenhernieninzidenz zu beeinflussen.

PVDF as a new polymer for the construction of surgical meshes

Abdominal hernia repair is the most frequently performed operation in surgery. Mostly due to lowered recurrence rates mesh repairs in hernia surgery have become an integral component despite increasing mesh-related complications. Current available mesh prosthesis are made of polypropylene (PP). polyethylene-terephtalat or polytetrafluorethylene. though all of them reveal some disadvantages. The introduction of new materials seems to be advisable. Caused by supposed advantageous textile properties and tissue response two mesh modifications made of polyvinylidene fluoride (PVDF) for abdominal hernia repair were developed. In the present study the PVDF meshes were compared to a common heavy weight PP-mesh (Prolene) in regard to functional consequences and morphological tissue response. After implantation in rats as inlay for 3, 14, 21, 42 and 90 days abdominal wall mobility was recorded by three-dimensional photogrammetry. Tensile strength of the suture zone and the mesh itself were determined. Explanted tissue samples have been investigated for their histological reaction in regard to the inflammatory infiltrate. vascularisation, connective and fat tissue ingrowth. Number of granulocytes, macrophages, fibroblasts, lymphocytes and foreign giant body cells have been evaluated to reflect quality of tissue response. The cellular response was grasped by measurement of DNA strand breaks and apoptosis (TUNEL), proliferation (Ki67) and cell stress (HSP70). Analyzing the results confirmed that construction of hernia meshes made of PVDF could be an advantageous alternative to the commonly used materials due to an improved biostability. lowered bending stiffness and a minimum tissue response.

Update with level 1 studies of the European Hernia Society guidelines on the treatment of inguinal hernia in adult patients

Purpose In 2009, the European Hernia Society published the EHS Guidelines for the Treatment of Inguinal Hernia in Adult Patients. The Guidelines contain recommendations for the treatment of inguinal hernia from diagnosis till aftercare. The guidelines expired January 1, 2012. To keep them updated, a revision of the guidelines was planned including new level 1 evidence.MethodsThe original Oxford Centre for Evidence-Based Medicine ranking was used. All relevant level 1A and level 1B literature from May 2008 to June 2010 was searched (Medline and Cochrane) by the Working Group members. All chapters were attributed to the two responsible authors in the initial guidelines document. One new chapter on fixation techniques was added. The quality was assessed by the Working Group members during a 2-day meeting and the data were analysed, especially with respect to any change in the level and/or text of any of the conclusions or recommendations of the initial guidelines. In the end, all relevant references published until January 1, 2013 were included. The final text was approved by all Working Group members.ResultsFor the following topics, the conclusions and/or recommendations have been changed: indications for treatment, treatment of inguinal hernia, day surgery, antibiotic prophylaxis, training, postoperative pain control and chronic pain. The addendum contains all current level 1 conclusions, Grade A recommendations and new Grade B recommendations based on new level 1 evidence (with the changes in bold).ConclusionsDespite the fact that the Working Group responsible for it tried to represent most kinds of surgeons treating inguinal hernias, such general guidelines inevitably must be fitted to the daily practice of every individual surgeon treating his/her patients. There is no doubt that the future of guideline implementation will strongly depend on the development of easy to use decision support algorithms tailored to the individual patient and on evaluating the effect of guideline implementation on surgical outcome. At the 35th International Congress of the EHS in Gdansk, Poland (May 12–15, 2013), it was decided that the EHS, IEHS and EAES will collaborate from now on with the final goal to publish new joint guidelines, most likely in 2015.

Abnormal collagen I to III distribution in the skin of patients with incisional hernia.

The surgical mesh-free repair of incisional hernias has to face recurrence rates of up to 50%. Apart from technical faults this is probably due to collagen metabolic disorders, known to play an important role in the development of inguinal hernia. In particular an altered ratio of collagen types I and III with an increase in collagen type III has been claimed to reduce the mechanical strength of connective tissues. Therefore, we investigated the content of collagen types I and III in the skin of patients with incisional hernia (n = 7) and recurrent incisional hernia (n = 5) in comparison to controls with healthy skin (n = 7) and normal skin scar (n = 7) both by immunohistochemistry and Western blot analysis. Both immunohistochemistry and Western blot analysis revealed a decrease in the ratio of collagen I/III due to a concomitant increase in collagen III. The patients with incisional hernias and with recurrent incisional hernias showed a ratio of 1.0 ± 0.1 and 0.8 ± 0.1, respectively, whereas the controls exhibit a ratio of 2.1 ± 0.2 in healthy skin and of 1.2 ± 0.2 in normal skin scar, respectively. The decrease was highly significant (p < 0.01) between the patients with either primary or recurrent hernia and the controls or the normal scar, as well as between controls and normal scar, whereas there was not any significant difference between primary and recurrent hernia (p > 0.05). Our data for the first time confirmed that the presence of incisional hernia is accompanied by impaired collagen synthesis in the skin. The decreased tensile strength of collagen type III may play a key role in the development of incisional hernias. Furthermore, it might explain the high recurrence rates of hernia repair by simple closure, as a repetition of the primarily failing technique, and the improvement by the additional use of alloplastic material.