Susceptibility of prosthetic biomaterials to infection

Mesh infection in ventral incisional hernia repair: incidence, contributing factors, and treatment

BACKGROUND

Prosthetic mesh infection is a catastrophic complication of ventral incisional hernia (VIH) repair.

METHODS

The current surgical literature was reviewed to determine the incidence, microbiology, risk factors, and treatment of mesh infections.

RESULTS

Mesh infections tend to present late. Diagnosis depends on high clinical suspicion and relies on culture of the fluid surrounding the mesh or of the mesh itself. Risk factors may include a high body mass index (obesity); chronic obstructive pulmonary disease; abdominal aortic aneurysm repair; prior surgical site infection; use of larger, microporous, or expanded polytetrafluoroethylene mesh; performance of other procedures via the same incision at the time of repair; longer operative time; lack of tissue coverage of the mesh; enterotomy; and enterocutaneous fistula. The best treatment is prevention. Treatment of mesh infection is evolving on a case-by-case basis from explantation toward mesh salvage, to prevent complications such as hernia recurrence.

CONCLUSION

Higher-quality reporting on mesh infection in VIH repair must be achieved through better classification and quantification of these infections. Tactics to avoid mesh infection should be based on best evidence and high-quality prospective trials and observational studies.

Comparison of the adherence of E.Coli and S. Aureus to ten different prosthetic mesh grafts: In vitro experimental study

BACKGROUND

The prosthetic mesh grafts used to repair the abdominal wall may become infected, primarily by S. aureus and E. coli. This study sought to provide a rational basis for the choice of mesh used to repair a hernia when there is a likelihood of infection or contamination.

METHODS

S. aureus and E. coli were incubated with ten types of prosthetic mesh graft (Table 1) in liquid growth medium. After sequential dilution of samples from the prosthetic mesh grafts, the colony forming units of adherent S. aureus and E. coli were counted.

RESULTS

There was no significant difference in the numbers of E. coli and S. aureus adherent to simple polypropylene mesh grafts. Significantly more of both species were adherent to the polyester, expanded polytetrafluoroethylene (ePTFE), and composite prosthetic mesh grafts, except for E. coli on graft 5. Significantly fewer E. coli were adherent to composite mesh grafts 5, 8, and 10 than S. aureus.

CONCLUSION

S. aureus and E. coli adhere to polypropylene similarly. In vitro, fewer S. aureus and E. coli adhere to simple polypropylene mesh grafts than to polyester, ePTFE, or composite prosthetic mesh grafts.

Regarding extremely large inguinal hernias with a contribution of two cases

We report two men of ages 62 and 80 years, respectively, with giant inguinoscrotal hernias. They were operated with a single-stage repair by two approaches, extended preperitoneal of Nyhus and an inguinal method. After hernia content reduction, a policaproamide antimicrobial mesh Ampoxen (MEDICA SA, Sandanski, Bulgaria) with dimensions 20 x 30 cm was inserted by using Stoppa's technique. An additional inguinal reinforcement with other mesh patch was done on the external aponeurosis hernial defect. Synchronous orchiectomy and transscrotal drainage of both patients was performed. The first patient suffering from umbilical hernia was also operated at the same stage. He was prepared by preoperative pneumoperitoneum. The second patient, due to scrotal skin cellulitis with ulceration, was operated without pneumoperitoneum preparation. The latter created easier mobilization and reduction of the hernial content. The sizable mesh dimensions allowed, to some degree, an acceptable level of intra-abdominal pressure after the repair. These hernias demand interdisciplinary teamwork and their treatment has to be adapted to the individual condition of the patient using all therapeutic options.