Eliza Russu, Adrian Vasile Mureșan, Bogdan Andrei Cordoș, Constantin Copotoiu and Ovidiu Simion Cotoi
Objective: Tissue integration of vascular grafts partially depends on the host response to injury, which immediately begins after implantation and restoration of the circulation. In an infected environment, the inflammation changes the incorporation patterns. The aim of the study was to observe the tissue incorporation process, in a normal and an infected environment. Methods: We have created an experimental model by performing subfascial implantation of four types of vascular grafts, in rats (woven Dacron®, knitted Dacron®, silver coated Dacron® and expanded Polytetrafloroethylene - ePTFE) and by infecting some of them with three different bacterial strains. We have retrieved the noninfected grafts at two and four weeks after implantation, whilst the infected ones at one, two and three weeks. Results: Detailed microscopic appearences were analysed. The control and infected groups were compared. Statistical significance was calculated for various corelations. Conclusions: The morphopathological findings showed that the ePTFE graft’s structure was best preserved. Statistical significance existed between the bacterial strain and the degree of inflammation. The silver coated Dacron® was not shown to be superior to the knitted Dacron®. The poorest incorporation was the one of the woven Dacron®.
Russu Eliza, Mureşan Adrian Vasile, Cordoş Bogdan Andrei, Cotoi Ovidiu Simion and Copotoiu Constantin
Objective: Starting with the ‘Vinyon-N-revolution’ of the 50’s, there has been a constant interest in understanting tissue integration, or the so-called graft healing process, as well as its relationship with infection. In this study we present an experimental animal model designed to assess tissue integration of different graft materials, and their reaction to the presence of infection.
Methods: Synthetic grafts (knitted Dacron®, woven Dacron®, silver-impregnated Dacron® and Gore-Tex®) were implanted subfascially in the interscapular region of Wistar rats. Animals were divided into a control group and an infected group, with infection induced using bacterial suspensions of standard strains of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli. Implants were retrieved at 2 and 4 weeks postoperatively in the control group and at 1, 2 and 3 weeks postoperatively in theinfected group. Retrieved grafts were assessed bacteriologically and morpho-pathologically.
Results: All microorganisms produced clinically evident infections, with positive blood cultures in case of E. coli. Staphylococci produced more massive infections on Dacron® grafts, except for the silver-impregnated version, while E. coli produced more significant infections on Gore-Tex® grafts. Morpho-pathologically Dacron® grafts behaved poorly, with ocassional complete structural compromise, and no difference between the conventional and the silver-impregnated type. The Gore-Tex® graft showed a consistent structural resistance throughout the study period.
Conclusions: Although the silver-impregnated graft inhibited bacterial growth, it was poorly tolerated by the host tissue. In contrast, Gore-Tex® grafts showed more massive infection, especially with E. coli, but kept their structural integrity surprisingly well.
Adriana Mocian, Eliza Russu, Reka Kaller and Adrian Mureșan
Chronic mesenteric artery disease has a much lower incidence than the acute one, but it raises the same problems in terms of patient survival. The long-term outcomes for open surgery are crucial for the right choice of a particular technique. We present the case of a 39-year-old female patient with a history of total nephrectomy, chronic kidney failure, and hypertension, who presented in the Emergency Department with abdominal pain with high intensity, for which she was admitted to the General Surgery Department. Abdominal computed tomography angiography was performed, which indicated the diagnosis of partial upper mesenteric artery stenosis. The patient underwent surgery, during which a retrograde aorto-mesenteric bypass with a Gore-Tex 5 mm diameter prosthesis was performed. In situations where the endovascular approach fails or has no indication (multiple incidence lesions from the origin of the superior mesenteric artery), open surgery is the indication in chronic mesenteric ischemia.