Incisional hernia

Treatment of abdominal wall hernia with suture, or polypropylene, or collagen prosthesis

PURPOSE

To develop an experimental model for incisional hernias and to compare morphological and functional aspects of hernia repairs by suture, polypropylene mesh and collagen mesh.

METHODS

A defect measuring 7cm x 2cm was created in the anterior abdominal of 28 New Zealand male rabbits, divided into four groups (n = 7): (1) control, (2) suture of the anterior sheath of the rectus abdominal muscle, (3) setting of polypropylene mesh, and (4) setting of collagen mesh. On the 90th postoperative day, the animals were examined to verify the presence of incisional hernia. Samples of abdominal wall and scar were collected for histological study.

RESULTS

Incisional hernia was identified in 85.7% of the control group, 57.1% of the suture group, 42.9% of the collagen mesh group, and none in the polypropylene mesh group (p = 0.015). Mesh exposure could be identified in 71.4% of the animals in group 3 and in no animal in group 4 (p = 0.021). The polypropylene mesh is effective in the treatment of abdominal wall defects, causing an intense inflammatory reaction.

CONCLUSION

The collagen mesh is biocompatible, producing a minimal inflammatory reaction, but fails in the treatment of abdominal wall defects.

Hernia emergencies

Hernia emergencies are commonly encountered by the acute care surgeon. Although the location and contents may vary, the basic principles are constant: address the life-threatening problem first, then perform the safest and most durable hernia repair possible. Mesh reinforcement provides the most durable long-term results. Underlay positioning is associated with the best outcomes. Components separation is a useful technique to achieve tension-free primary fascial reapproximation. The choice of mesh is dictated by the degree of contamination. Internal herniation is rare, and preoperative diagnosis remains difficult. In all hernia emergencies, morbidity is high, and postoperative wound complications should be anticipated.

Repair of High-Risk Incisional Hernias and Traumatic Abdominal Wall Defects with Porcine Mesh

Complex ventral hernias represent a significant challenge to surgeons. We hypothesized that a wide underlay technique in combination with a novel biologic mesh would result in repair with a low recurrence rate. Medical records of patients undergoing ventral herniorrhaphy with Xen-Matrix biologic mesh were evaluated. All patients were evaluated for hernia recurrence both immediately and after 2 to 3 years. There were 57 patients included in the study. The overall recurrence rate was 7.2 per cent; however, all recurrences were early and were likely technical failures. The average duration of follow-up was 30.6 months with no further recurrences after the early technical failures. The average number of previous recurrences was 1.5. Fascial closure was obtained over the mesh in 84 per cent of patients, with component separation being necessary in 36 per cent of patients. Lack of fascial reapproximation over the mesh was associated with early recurrence (0 vs 55%, P < 0.0001). Complex ventral hernias can be repaired with a low recurrence rate. Our technique in combination with the XenMatrix biologic mesh provides for durable repair. Whenever possible, the fascia should be closed above the underlay mesh, because this technique provides a more durable repair than using the mesh as a “fascial bridge.”

Prosthetic strap system for simplified ventral hernia repair: results of a porcine experimental model

INTRODUCTION

Aiming to achieve a simplified ventral hernia repair, a proprietary oval-shaped mesh was experimentally tested in a porcine model. The mesh is structured with a large central body and radiating straps. The friction of the straps passing through the tissues are hypothesized to be adequate to maintain the position of the mesh during tissue ingrowth, avoiding classic point fixation while ensuring a wide coverage of the abdomen.

METHODS

The mesh, having six radial straps, was placed using a sublay preperitoneal technique in four pigs. All straps were passed laterally through the abdominal wall and exteriorized from the skin. The straps were trimmed at the level of the skin, allowing the stumps to recoil into the subcutaneous space. The animals were euthanized at 1 and 4 months to determine the integration of the straps.

RESULTS

Macroscopically, all 24 straps were firmly incorporated within the abdominal wall. The tension-free placement of the mesh by using the straps was effective. The friction of the straps passing through the tissues was adequate to keep the mesh well orientated. No dislocation of the implants was observed. The strap system also allowed a broader coverage of the abdominal wall, far beyond the wound opening.

CONCLUSIONS

The described arm system of the aforementioned implant seems to be effective in eliminating point fixation of the mesh. The fixation arms seemed to have ensured that the mesh stayed orientated in all of the animals. A very wide lateral mesh placement was accomplished, assuring sufficient defect overlap when shrinkage occurs.

A comparative study of adhesion formation and abdominal wall ingrowth after laparoscopic ventral hernia repair in a porcine model using multiple types of mesh

BACKGROUND

The ideal mesh for laparoscopic ventral hernia repair is not yet identified.

METHODS

We laparoscopically placed polypropylene (PPM), expanded polytetrafluoroethylene (ePTFE), and polyester with antiadhesive collagen layer (PCO) in eight pigs using sutures and tacks for fixation. After 28-day survival, we compared adhesion formation, fibrous ingrowth, and shrinkage among the types of mesh.

RESULTS

Mean area of adhesions to PCO (8.25%) was less than that to ePTFE (57.14%, p < 0.001) or PPM (79.38%, p < 0.001). Adhesions peel strength was less for PCO (2.3 N) than for PPM (16.1 N, p < 0.001) or ePTFE (8.8 N, p = 0.02). Peel strength of mesh from the abdominal wall was less for ePTFE (1.3 N/cm of mesh width) than for PCO (2.8 N/cm, p = 0.001) or PPM (2.1 N/cm, p = 0.05). ePTFE area (94.4 cm(2)) was less than that for PCO (118.6 cm(2), p < 0.001) or PPM (140.7 cm(2), p < 0.02).

CONCLUSION

PCO had fewer and less severe adhesions than ePTFE or PPM while facilitating excellent ingrowth of the adjacent parietal tissue.

Simplified technique for incisional hernia repair with mesh prosthesis

This paper describes a simplified technique for the repair of incisional hernias. The previous scar is resected, and the peritoneal sac is carefully dissected until it is completely exposed. The sac is opened to liberate structures adherent to the sac or to the area immediately surrounding the defect. The peritoneum is closed and invaginated to form a sac bed underlying the entire extent of the defect, and the mesh is laid on this sac bed. The mesh is then fixed with "U" stitches, reinforcing these by inserting a second line from the edge of the defect to the mesh. Suture material used is polypropylene 1/0 or 2/0. This procedure has been carried out on 15 patients, and after 1 year of follow-up, there has been no recurrence of the hernia. Operating time was reduced, and the surgical technique was found to be easier. Placing a mesh prosthesis inside the hernia sac and fixing it to the abdominal wall with two lines of suturing simplifies the repair procedure, reduces operating time, and is effective in the repair of all incisional hernias. A study is required to compare this outcome with the different mesh repair techniques.

Have outcomes of incisional hernia repair improved with time? A population-based analysis

OBJECTIVE

To determine if certain outcomes of incisional hernia repair have improved in recent eras.

SUMMARY BACKGROUND DATA

Technological developments have been reported to improve outcomes in the repair of abdominal wall incisional hernias.

METHODS

This retrospective, population-based cohort study was conducted using a 1987 to 1999 Washington hospital discharge database. Subjects were all Washington state residents assigned ICD9 procedure codes for incisional hernia repair with or without synthetic material (mesh). Main outcome measure was the rate of reoperative incisional hernia repair, length of hospitalization, and hospital charges based on the use of synthetic material and the era of operative repair (before and after 1995).

RESULTS

A total of 10,822 Washington state patients underwent incisional hernia repair (mean age 58.7 +/- 15.6, 64% female). Of patients undergoing incisional hernia repair, 12.3% underwent at least one subsequent reoperative incisional hernia repair within the first 5 years after initial repair (23.1% at 13 years follow-up). The 5-year reoperative rate was 23.8% after the first reoperation, 35.3% after the second, and 38.7% after the third. The use of synthetic mesh in incisional hernia repairs increased from 34.2% in 1987 to 65.5% in 1999. When controlling for age, sex, comorbidity index of the patient, year of the initial procedure, and hospital descriptors (rural location, nonprofit and teaching status), the hazard for recurrence was 24.1% higher if no mesh was used compared to the hazard if mesh was used. After similar adjustment, no differences were found in the hazard of reoperation based on the era of the operative repair. Mean length of stay for procedures performed after 1995 was 4.9 days compared to 4.8 days in preceding eras.

CONCLUSIONS

Incisional hernia repair is associated with high cumulative rates of reoperative repairs. The expectation that important measures of adverse outcome have improved in recent eras is not supported by the results of this large population-based study.