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U Klinge

Publications and source records attributed to U Klinge.

At least 55 records · Page 3Linked to original sources
PubMed2003

[Information on the Internet for patients and general practitioners--critical analysis using the example of inguinal hernia].

INTRODUCTION: The Internet offers an increasing amount of medical information, but its value for surgical patients is doubtful. METHODS: Using "inguinal hernia" as catchword, an amateur search was imitated on a German-speaking metasearch machine. One hundred fifty sites, standardized regarding quality and efficiency,were evaluated. RESULTS: In summary, more than 50% of the sites revealed poor results. Technical appearance, quality of content, and target grouping show big deficiencies. The applicable laws were mostly not respected. The ranking lists of the search machines do not reflect the quality of the sites. CONCLUSION: Patients need competent guides to process surgical information from the Internet. The establishment of a specialized institution to control surgical websites according to quality, content, and legality seems to be needed.

Family Practice↗
PubMed2002

Temporary closure of the abdominal wall (laparostomy).

The definitive closure of the abdominal wall, i.e., a closure of the fascial layer and skin may not be favorable in the treatment of numerous surgical conditions, e.g., peritonitis, trauma, or mesenteric ischemia. In these cases, the abdominal wall is temporarily closed, and a laparostomy is created to facilitate re-exploration or to prevent abdominal compartment syndrome. Regarding the technique and material used for the temporary closure, no prospective randomized data exists, but mesh materials are commonly used. They provide drainage of infectious material, permit visual control of the underlying viscera, facilitate access to the abdominal wall, preserve the fascial margin, enable healing by secondary intention, and allow mobilization of the patient. In the case of decreasing intra-abdominal pressure, meshes can be trimmed to centralize the rectus muscle and to facilitate definitive closure. Non-absorbable meshes have been frequently reported to cause enteric fistulae and persistent infection necessitating mesh explantation. While these infectious complications appear to occur less frequently with the use of absorbable materials, these meshes will finally lead to an incisional hernia, requiring repair with non-absorbable mesh after a period of 6-12 months. Nevertheless, in the complex situation requiring a temporary abdominal wall closure, use of absorbable mesh material is common and represents the state of the art.

Abdominal Cavity↗
PubMed2002

Influence of laparotomy closure technique on collagen synthesis in the incisional region.

BACKGROUND: Variations of suture technique have an influence on the mechanical strength of laparotomy wounds. To investigate whether these differences in biomechanical properties influence collagen synthesis in the incisional region, an animal experiment on laparotomy closure was performed. MATERIAL: In 100 rats median laparotomies were closed with polypropylene. Continuous and single sutures were applied with variations of suture length to wound length (SLWL) ratio and suture tension. METHODS: Tissue samples from the incisional region after 2 and 4 weeks were analysed spectro-photometrically for the concentration of collagen protein and by digital image analysis for the percentage of collagen type III. RESULTS: Running closure with an SLWL ratio >or=4:1 resulted in a significantly higher concentration of collagen protein than single sutures with the same SLWL ratio. In contrast, single closure with an SLWL ratio <4:1 led to in a higher collagen protein concentration than running closure with the same SLWL ratio. With an SLWL ratio >or=4:1 running sutures resulted in a significant reduction of the percentage of collagen type III after 4 weeks compared to single sutures. Closure with high suture tension led to a significant reduction of collagen protein between the 2nd and 4th week but left the percentage of collagen type III mostly unaffected. CONCLUSION: Suture technique, SLWL ratio, and suture tension have an effect on the ultrastructural composition of the regenerating tissue. This influence outlasts the period of tissue restructuring during which the presence of sutures in the incisional edges is absolutely required. Running sutures with an SLWL ratio >or=4:1 and low suture tension promote a favourable collagen composition of the incisional region.

Animals↗
PubMed2002

Intra-abdominal pressure: a reliable criterion for laparostomy closure?

BACKGROUND: Laparostomy is frequently performed in the surgical therapy of mechanical obstruction, peritonitis, or trauma to prevent abdominal compartment syndrome (ACS). Extended incisional hernia is inevitable when fascial closure is missed (up to 90% of cases). Intra-abdominal pressure (IAP) has not yet been evaluated as a criterion for the feasibility of fascial closure. PATIENTS AND METHODS: Over 12 months laparostomy was carried out in 40 patients. Definitive closure of the abdomen was performed after 4.4+/-3.7 days in 23 of these. Intravesical pressure was used to assess IAP before and after fascial closure. The resulting IAP was compared to the values of 90 patients undergoing elective abdominal surgery. Parameters of cardiocirculatory, renal, pulmonary, and liver function were also recorded. RESULTS: After closure of the laparostomy IAP increased significantly from 6.5+/-3.3 to 12.0+/-4.1 mmHg. Urine output decreased by 27% on the first postoperative day but regained normal levels thereafter. The central venous pressure increased by 31%. Other parameters of cardiocirculatory, renal, pulmonary, and liver function were unchanged. No case of ACS occurred. In the patients undergoing elective abdominal surgery IAP ranged from 6.5+/-2.1 to 10.0+/-4.0 mmHg. CONCLUSIONS: Fascial closure increased the IAP, which was accompanied by short-termed decrease in urine output. At these levels of IAP fascial closure appears to be harmless, but further prospective studies are needed to determine the critical level of IAP for allowing a safe repair of large fascial defects.

Abdominal Cavity↗
PubMed2002

Functional and morphological evaluation of a low-weight, monofilament polypropylene mesh for hernia repair.

With more than 1 million implantations per year worldwide, mesh repair has become a standard procedure for the treatment of hernias. Apart from various technical problems, the type of material has been proven to be of considerable importance for the functional and histological outcome, particularly for long-term implantation. Whereas the advantageous application of low-weight, large-pore meshes based on multifilaments can be stated without doubt, it is still open whether similar results can be achieved on the basis of pure monofilaments. In the present study, a low-weight polypropylene mesh (LW) made purely of monofilaments was compared to a common heavy-weight polypropylene mesh (HW) in regard to the functional consequences and the tissue response. After implantation in rats as an inlay for 3--90 days, the abdominal-wall mobility of the implant region was recorded by 3D stereography, and the tensile strength of both the suture zone and the mesh was measured. The morphometry of the histological reaction in regard to the inflammatory infiltrate, the connective tissue, the number of granulocytes, macrophages, and fibroblasts served to reflect the tissue response. As parameters for the remodeling process at the interface the cellular activation was evaluated by TUNEL (DNA-strand breaks or apoptosis, respectively), Ki 67 (cell proliferation), and HSP 70 (cell stress). The measured tensile strength of the LW mesh confirmed a sufficient strength of the material-reduced mesh modification. After implantation the consecutive impairment of the abdominal-wall mobility was reduced compared to the HW mesh, concomitant to the reduced fibrotic level at the interface. At the end of the observation period the foreign-body reaction was significantly lowered for the LW mesh, almost reaching physiological values. In conclusion, these data confirm the improved biocompatibility of material-reduced mesh implants.

Abdominal Wall↗
PubMed2002

Do multifilament alloplastic meshes increase the infection rate? Analysis of the polymeric surface, the bacteria adherence, and the in vivo consequences in a rat model.

Within the last decade hernia surgery has changed from suture repair to mesh repair. Biomaterials, and multifilaments in particular, are thought to increase the risk of infection. Therefore, the aim of this study was to study the influence of the presence of either a monofilament or a multifilament mesh material on the bacterial infection risk. The filament surface of a monofilament and a multifilament mesh were calculated on the basis of a theoretical model. The adherence of Staphylococcus aureus was measured in vitro by fluorescence analysis. Additionally, the two mesh materials (8-mm platelets) were implanted subcutaneously in Sprague-Dawley rats with daily surveillance for clinical signs of infection. After 7 days the meshes were explanted for histological and microbiological analysis. Calculations of the mesh surface area revealed a higher level for the multifilament mesh. The extent of adherent bacteria corresponded to the estimated filament surface in vitro. In vivo, the implantation of meshes in the presence of 5 x 10(6) S. aureus did not show an increased infection rate in rats with either monofilament or multifilament material, compared to the control groups (mesh implantation without S. aureus contamination). However, after 7 days bacteria were still detectable in the majority of the implantation sites, and a clinically inapparent intensification of local inflammation and fibrosis was induced. The increased surface area of a multifilament meshes promotes the persistence of bacteria in the implant bed, though this alone is not sufficient to create a clinically apparent infection. This might explain the development of mesh-related infections after a delay of several months or even years. In vivo, the adherence of bacteria to the implant material depends on the surface area, which favors the use of monofilament materials.

Animals↗
PubMed2002

Impact of polymer pore size on the interface scar formation in a rat model.

BACKGROUND: The surgical therapy of hernias is increasingly based on reinforcement with alloplastic material, in particular surgical meshes. The biological response to these foreign bodies largely depends on the selected material and its structure. In comparison to the physiological scar process following a simple abdominal wall incision, the chronic inflammation at the interface to the polymers lead to specific morphological alterations. MATERIALS AND METHODS: In the present study two meshes with different pore sizes were implanted into rats: a heavy-weight and small-pore-sized mesh (hw-mesh) made of nonabsorbable polypropylene monofilaments and a low-weight large-pore-sized mesh consisting of polypropylene and of absorbable polyglactin multifilaments (lw-mesh). A suture repair of a laparotomy served as control. After 7, 14, 21, and 90 days the mesh area was analyzed with regard to tissue and cellular response. RESULTS: Over the whole observation period morphometric analysis indicated an improved integration of the lw-mesh with reduction of both inflammation and fibrosis, whereas the hw-mesh induced an intense chronic inflammation concomitant with an intensified bridging scar reaction. On the cellular level these findings correspond to an elevated cell turnover, characterized by increased rates of apoptotic and proliferating cells. In contrast, the tissue reaction to the lw-mesh achieved levels almost similar to those of the physiological scaring process in the control group. CONCLUSION: In conclusion, the present data confirm the development of a chronic inflammatory foreign body reaction at the interface to both hw-meshes and lw-meshes; however, the use of lw-meshes showed superior tissue integration. With regard to the quite similar polymer surface the pore size appears to be of major importance in tissue reaction and for the biocompatibility of mesh structures.

Animals↗
PubMed2002

[Factors influencing the development of incisional hernia. A retrospective study of 2,983 laparotomy patients over a period of 10 years].

INTRODUCTION: 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 chi 2-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 perfusin seem to exert a positive influence on incisional hernia incidence.

Age Factors↗
PubMed2002

[Update on incisional hernia. Parastomal hernia].

Parastomal herniation is a frequent complication when an artificial anus is constructed. As a tunnel through the abdominal wall is nonphysiological, there is an inherent trend to enlargement of the aperture with any artificial stoma. However, none of the technical modifications tried has proved reliable in reducing the incidence of parastomal herniation. The only clear-cut indications for repair are ileus and incarceration or serious problems with the colostomy bags. There are three basic methods of repair: fascial closure, stoma relocation and augmentation of the abdominal wall by nonabsorbable meshes, and any of the three can be combined in many ways. The first two techniques each have a recurrence rate of 40%-80%, and neither can therefore any longer be recommended for use in isolation. Only with the last technique of abdominal wall reinforcement it is possible to achieve a recurrence rate of under 20%. The best type of mesh and the optimal implantation technique are still under discussion.

Colostomy↗
PubMed2002

[Retromuscular mesh repair for ventral incision hernia in Germany].

Since the onset of an incisional hernia is caused by the biological problem of forming stable scar tissue, the mesh techniques are now the methods of choice for incisional hernia repair. Polypropylene is the material most widely used for open mesh repair. New developments have led to low-weight, large-pore polypropylene prostheses, which have been adapted to the physiological requirements of the abdominal wall and permit a reliable tissue integration. These meshes make it possible for a scar net to form rather than a stiff scar plate, thus helping to avoid the complications encountered with the use of earlier meshes. The ideal position for the mesh seems to be the retromuscular underlay position, in which the force of abdominal pressure holds the prosthesis tightly against the deep surface of the muscles. The retromuscular underlay repair technique has yielded the lowest incidence rates for recurrence: around 10% even after long-term follow up. Analysis of the failures after open mesh repair suggests that inadequate size of the mesh with insufficient overlap at the edges is the main reason for recurrence. An overlap of at least 5-6 cm all round must therefore be considered mandatory for successful reinforcement of the abdominal wall. Open mesh repair, particularly with modern low-weight polypropylene meshes applied by the retromuscular underlay technique, offers excellent results in the treatment of incision hernias, even in long-term follow-up studies.

Abdominal Wall↗
PubMed2002

[Prevention of incisional hernia].

Incisional hernia is the most frequent late complication of surgery; its incidence is constant and it has a high socio-economic impact. Possible preventive measures are analysed in this article on the basis of current clinical and experimental findings. An argument that is restricted strictly to the surgical and technical aspects does not do justice to the complexity of incisional hernia development. It has been proved that continuous mattress suturing after laparotomy is beneficial in terms of wound healing and also means significantly shorter operating times and smaller amounts of suture material are needed. Combined with a suture length-to-wound length ratio of at least 4:1, this technique is superior to single interrupted suturing as its bio-mechanical properties are better and it allows better collagen synthesis in the region of the incision. It is not possible to recommend any one particular suture material at present. The possibilities of influencing the endogenous risk factors connected with the patient and any co-morbidity is hampered by economic aspects and low efficiency, although precisely such endogenous factors have a high potential for influencing treatment in the future. Suture tension is a relevant parameter that has not yet been sufficiently fully evaluated. Better monitoring of suture tension might open up the possibility of devising new variants of laparotomy closure techniques that would reduce the incidence of incisional hernias. In view of the significance of impaired wound healing for the surgical specialties, suture tension and the search for possible ways of influencing and modulating collagen synthesis look like promising topics that would reward a more intense research effort in the future.

Hernia, Ventral↗
PubMed2002

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.

Animals↗
PubMed2002

Influence of implantation interval on the long-term biocompatibility of surgical mesh.

BACKGROUND: The aim was to study the long-term tissue response to polypropylene mesh. METHODS: This was a retrieval study that investigated 76 polypropylene meshes with a median implantation interval of 18 (range 2-180) months. Mesh was explanted following hernia recurrence, infection or pain. The median implantation interval was 20 (range 4-180) months in the recurrence group, 30 (range 5-48) months in the pain group and 10 (range 2-56) months in the infection group (P < 0.05, infection versus pain or recurrence). The inflammatory response was determined by immunohistochemistry of macrophages (CD68), polymorphonuclear granulocytes (CD15) and T and B lymphocytes (CD3 and CD20). The cell turnover within the interface mesh fibre-recipient tissue was measured by TUNEL for apoptosis or DNA strand breaks, Ki67 for cell proliferation and heat-shock protein (HSP) 70 for cell stress. RESULTS: With the exception of HSP-70, levels of all variables decreased over time. Sex, age, type of previous operation or location of the mesh did not have a significant influence. CONCLUSION: Long-term incorporated polypropylene mesh in humans has a more favourable tissue response with increasing implantation interval.

Adult↗
PubMed2002

[Meshes in inguinal hernia repair].

Repair of a groin hernia is strongly influenced by prosthetic mesh implantation carried out in nearly 50 % of all operations. Recurrency rates, however, did not decrease by this policy. Many different materials are available. Due to bioinstability on the long-term and elevated infection rates PTFE is not suitable for inguinal hernia repair. Polyester also provides no long-term stability and induces a chronic foreign body reaction. Polypropylene initially leads to an acute inflammatory reaction and often ends in fibrosis. Both reactions are related to the weight of the used mesh. All materials may lead to specific complications. These include seroma formation, infection, migration of the prosthesis with arrosion of organs, damage of the vas deferens, development of recurrency by shrinkage of the fibers around the mesh, formation of adhesions in the preperitoneal position, and chronic inguinal pain. Therefore, meshes should be used only after individual estimation of risks and benefit. This includes the hernia classification, the number of previous operations and the possibility of a defect in collagen metabolism. The unknown long-term risks for the patient may be taken only in strong indications.

Hernia, Inguinal↗
PubMed2001

The surgical trauma of abdominal wall incision. A comparison of laparoscopic vs open surgery with three-dimensional stereography.

BACKGROUND: Laparoscopic operations seem to respect the integrity of the abdominal wall better than conventional laparotomy, but the effects of surgical trauma are not well understood. The new technique of three-dimensional stereography makes it possible to describe and calculate the mobility of the abdominal wall and the nature of the underlying disturbances. METHODS: Three-dimensional stereography is a noninvasive optical method of measuring surface areas. Abdominal wall mobility can be assessed by comparing changes to the abdominal surface in its minimum and maximum excursions. Different parameters, such as height difference and curvature, are calculated. We studied patients undergoing different types of surgical procedures (laparoscopy and open surgery) by measuring their abdominal wall mobility before and after the procedure. We also compared these patients to a control group. Each group consisted of 30 patients, who were evaluated prospectively. RESULTS: We found a significant difference in abdominal wall mobility between patients treated via a laparoscopic approach, and those who had conventional surgery. At 7 days after laparoscopy, abdominal movement was always the same in the laparoscopic group as in the controls. By contrast, the open surgery group still showed a significant lack of mobility 12 days after the procedure. CONCLUSION: The new method of three-dimensional stereography makes it possible to compare the trauma associated with different surgical approaches as it affects the integrity of the abdominal wall. As compared with open surgery, laparoscopy has a significant positive effect on abdominal wall integrity.

Abdominal Muscles↗
PubMed2001

Increased distribution of collagen type III and reduced expression of matrix metalloproteinase 1 in patients with diverticular disease.

Diverticular disease is an increasingly common clinical problem especially in Western industrialized countries, but the mechanism by which the disease develops remains unclear. Based on studies showing a structural change in the colonic wall in these patients, we examined whether there are any disorders concerning the collagen metabolism in patients with diverticular disease. Samples of colonic tissue from 13 patients with diverticulitis were compared to 14 controls. We performed a Sirius red test for the overall collagen content and immunohistochemical studies facing differentiation between collagen type I and type III and the expression of matrix metalloproteinases 1 and 13. In the bowel sections of patients with diverticulitis there were decreased levels of mature collagen type I (1.37+/- 0.32 vs. 1.59 +/- 0.31) and increased levels of collagen type III (1.61+/- 0.32 vs. 1.42 +/- 0.42), with a resulting lower collagen ratio I/III. The expression of MMP-I was reduced significantly in the diverticulitis group (4.83 +/- 0.92 vs. 6.02 +/- 1.98) while expression of MMP-13 did not differ significantly between the two groups (1.03 +/- 0.11 vs. 1.04 +/- 0.12). Our findings support the theory of structural changes in the colonic wall as one of the major pathogenic factors in the development of diverticular disease. Further studies must focus on the complex interactions of several extracellular matrix components.

Adult↗