Operative treatment of ventral hernia using prosthetic materials

Operative Considerations for the General Surgeon in Patients with Chronic Liver Disease

Chronic liver disease remains a prevalent and challenging comorbidity in the American population at large. Scarring and fibrosis cause physical and physiological changes that may prove challenging in both medical and surgical management. However, because there has been relevant improvements in preoperative diagnostic, perioperative hepatologic, and intensive care management, as well as in surgical techniques, patients with cirrhosis can safely be operated on but patient selection remains vital. Patients with chronic liver disease may present to a general surgeon for evaluation of a number of elective or emergent surgical conditions. Here, we review current literature on the perioperative management and operative strategies of seemingly routine general surgery issues and provide a review of the pathophysiology associated with chronic liver disease.

Synthetic surgical meshes used in abdominal wall surgery: Part I-materials and structural conformation

Surgical implants are commonly used in abdominal wall surgery for hernia repair. Many different prostheses are currently offered to surgeons, comprising permanent synthetic polymer meshes and biologic scaffolds. There is a wide range of synthetic meshes currently available on the market with differing chemical compositions, fiber conformations, and mesh textures. These chemical and structural characteristics determine a specific biochemical and mechanical behavior and play a crucial role in guaranteeing a successful post-operative outcome. Although an increasing number of studies report on the structural and mechanical properties of synthetic surgical meshes, nowadays there are no consistent guidelines for the evaluation of mechanical biocompatibility or common criteria for the selection of prostheses. The aim of this work is to review synthetic meshes by considering the extensive bibliography documentation of their use in abdominal wall surgery, taking into account their material and structural properties, in Part I, and their mechanical behavior, in Part II. The main materials available for the manufacture of polymeric meshes are described, including references to their chemical composition, fiber conformation, and textile structural properties. These characteristics are decisive for the evaluation of mesh-tissue interaction process, including foreign body response, mesh encapsulation, infection, and adhesion formation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 689-699, 2017.

One and four layer acellular bladder matrix for fascial tissue reconstruction

To determine whether the use of multiple layers of acellular bladder matrix (ABM) is more suitable for the treatment of abdominal wall hernia than a single layered ABM. The feasibility, biocompatibility and mechanical properties of both materials were assessed and compared. Biocompatibility testing was performed on 4 and 1 layered ABM. The matrices were used to repair an abdominal hernia model in 24 rabbits. The animals were followed for up to 3 months. Immediately after euthanasia, the implant site was inspected and samples were retrieved for histology, scanning electron microscopy and biomechanical studies. Both acellular biomaterials demonstrated excellent biocompatibility. At the time of retrieval, there was no evidence of infection. The matrices demonstrated biomechanical properties comparable to native tissue. Three hernias (25%) were found in the single layer ABM group and only 1 hernia (8%) was found in the 4 layer ABM group. Histologically, the matrix structure was intact and the cell density within the matrices decreased with time. The dominant cell type present within the matrices shifted from lymphocytes to fibroblasts over time. Both ABMs maintained adequate strength over time when used for hernia repair, and there was an extremely low incidence of adhesion formation. The single layer ABM showed enhanced cellular integration, while the 4 layer ABM reduced hernia formation. Either of these matrices may be useful as an off-the-shelf biomaterial for patients requiring fascial repair.

A review of available prosthetics for ventral hernia repair

OBJECTIVE

To review mesh products currently available for ventral hernia repair and to evaluate their efficacy in complex repair, including contaminated and reoperative fields.

BACKGROUND

Although commonly referenced, the concept of the ideal prosthetic has never been fully realized. With the development of newer prosthetics and approaches to the ventral hernia repair, many surgeons do not fully understand the properties of the available prosthetics or the circumstances that warrant the use of a specific mesh.

METHODS

A systematic review of published literature from 1951 to June of 2009 was conducted to identify articles relating to ventral hernia repairs and the use of prosthetics in herniorrhaphy.

RESULTS

Important differences exist between the synthetics, composites, and biologic prosthetics used for ventral hernia repair in terms of mechanics, cost, and the ideal situation in which each should be used.

CONCLUSIONS

The use of synthetic mesh remains an appropriate solution for most ventral hernia repairs. Laparoscopic ventral hernia repair has created a niche for both expanded polytetrafluoroethylene and composite mesh, as they are suited to intraperitoneal placement. Preliminary studies have demonstrated that the newer biologic prosthetics are reasonable options for hernia repair in contaminated fields and for large abdominal wall defects; however, more studies need to be done before advocating the use of these biologics in other settings.

In vivo evaluation of acellular human dermis for abdominal wall repair

Limitations of synthetic biomaterials for abdominal wall repair have led investigators to seek naturally derived matrices, such as human acellular dermis, because of their excellent biocompatibility and their ability to naturally interface with host tissues with minimal tissue response. In this study, we investigated two different biomaterials derived from human dermis (FlexHD acellular dermis and FlexHD acellular dermis-thick) in a rabbit abdominal hernia repair model. One quarter of the abdominal wall was replaced with each biomaterial, and the animals were followed for up to 24 weeks. Rabbit hernias repaired with AlloDerm, a commercially available acellular dermal matrix, and sham operated animals served as controls. Retrieved samples of these implants were assessed grossly and histologically. Collagen production measurements and tension studies were performed. FlexHD acellular dermis, FlexHD acellular dermis-thick, and AlloDerm maintained their strength in the rabbit hernia repair model with no incidence of hernia formation or bowel adhesion. The exact size measurements at 24 weeks were 217.0 +/- 20.9% for FlexHD acellular dermis, 200.8 +/- 23.5% for FlexHD acellular dermis-thick, and 209.7 +/- 32.9% for AlloDerm. Macroscopic and microscopic evaluation showed excellent integration and tissue formation. All biomaterials studied harbored cells that produced new collagen fibers, and a six-fold increase in these fibers was observed at 24 weeks. This study shows that acellular biomaterials derived from human dermis are suitable for abdominal hernia repair.

Grandes hérnias incisionais

INTRODUÇÃO: A correção de hérnias incisionais abdominais permanece como um dos procedimentos cirúrgicos mais comuns uma vez que ela ocorre em cerca de 11% das laparotomias. Vários são os fatores de risco. Surgem, em geral, nos primeiros cinco anos após a operação e seu manuseio ainda é controverso. OBJETIVO: Atualizar os meios e métodos empregados para a correção cirúrgica das hérnias abdominais gigantes. MÉTODO: Revisão da literatura com base no Pubmed, Scielo e Lilacs com cruzamento dos descritores "hérnia abdominal, próteses, complicações e técnicas cirúrgicas", e adicionando contribuição própria baseada na experiência dos autores no manuseio desta afecção. CONCLUSÃO: Mesmo as correções bem sucedidas, com a utilização ou não de grandes próteses, não são os procedimentos isentos de inconvenientes, pois a parede abdominal não retoma a sua elasticidade e complacência normais. Por este motivo, é importante que o paciente seja alertado da possibilidade da sua expectativa em relação ao resultado, tanto estético quanto funcional, não ser alcançada.

Management of giant ventral hernia by polypropylene mesh and host tissue barrier: trial of simplification

BACKGROUND

Surgical management of giant ventral hernias is a surgical challenge due to limited abdominal cavity. This study evaluates management of giant ventral hernias using polypropylene mesh and host tissue barrier after suitable preoperative preparation.

METHODS

In the period from January 2005 and January 2007, 35 patients with giant ventral hernias underwent hernia repair. After careful preoperative preparation, repair was done using polypropylene mesh. The mesh was separated from the viscera by a small part of the hernia sac and the greater omentum.

RESULTS

The average age of the patients was 52. Twenty patients had post-operative incisional and 15 had para-umbilical hernias. The mean hernia defect size was 16.8 cm. Mean body mass index was 33. Follow up ranged from 18-36 months. No patient required ventilation after operation. Recurrent seroma, which responded to repeated aspiration, was experienced in 4 patients. Minor wound infection was observed in 5 patients. Small hernia recurrence occurred in one patient.

CONCLUSION

The use of polypropylene and host tissue barrier after suitable preoperative preparation is relatively simple, safe, and reliable surgical solution to the problem of giant ventral hernia.

KEYWORDS

Hernia repair; Giant ventral hernia; Polypropylene mesh.

Management of complicated umbilical hernias in cirrhotic patients using permanent mesh: randomized clinical trial

PURPOSE

The optimal management of complicated umbilical hernia in patients with liver cirrhosis is still undefined. The purpose of this study is to evaluate the use of polypropylene mesh to treat complicated umbilical hernia in cirrhotic patients.

METHODS

In the period from January 2005 to May 2008, 80 patients with complicated umbilical hernia combined with liver cirrhosis underwent hernia repair. The patients were randomly divided into two groups; each group consisted of 40 patients. Hernia repair was carried out by conventional fascial repair in group I and by mesh hernioplasty in group II.

RESULTS

The male/female ratio, Child-Pugh class, and mode of hernia complication were almost matched in both groups. Hernia recurrence was significantly less in the mesh hernioplasty group. No mesh exposure or fistulae were experienced. There was no need to remove any of the meshes.

CONCLUSIONS

Permanent mesh can be used in complicated hernias in cirrhotic patients with minimal wound-related morbidity and a significantly lower rate of recurrence.

Rectusbanding: a method for the repair of incisional hernias

BACKGROUND

We report on a new method of incisional hernia repair applicable to any size of hernia and the long-term results of this method. Musculus rectus abdominis is bandaged or partially bandaged in a loose way with a 2-cm-wide band of polypropylene (Prolene) on both sides at a distance of 2 cm, depending on the size of the hernial opening. The aims of this technique, which were defined in 1999 when we started using the method, were to find a simple method for surgeons, a safe mesh fixation and the prevention of a postoperative stiff abdomen. Another aim was to find a method for optimal patient care at reasonable costs.

METHODS

Two hundred and seventeen patients underwent an operation according to this method in our department from June 1999 until December 2007. The first 75 patients of this cohort were treated using a technique in which the musculus rectus abdominis was bandaged in a loose way. One hundred and forty-two patients (since October 2001) were treated using a technique in which the muscle was not entirely bandaged. Instead, the polypropylene bands, which had been placed in sublay position, were penetrating the lateral rim through incisions and were fastened there. We included 124 patients (October 2001 to December 2006) in our further examination with a follow-up of 17-79 months.

RESULTS

We found a recurrence rate of 6%, 80.1% of the patients had no trouble, 18.1% of the patients had very rarely any complaint, 0.9% of the patients had problems after exercise and 0.9% had permanent problems. All patients had excellent mobility of the abdomen.

CONCLUSION

This method was proven to give good results in the long run and can be easily learned by any surgeon. This method is a true alternative to all methods which have been published so far.