Prevention of Primary Vascular Graft Infection with Silver-Coated Polyester Graft in a Porcine Model

Abstract

Objectives To evaluate the efficacy of a silver-coated vascular polyester graft in the prevention of graft infection after inoculation with Staphylococcus aureus in a porcine model. Material and methods Eighty-four pigs were randomly selected 1:1 to receive a silver-coated or non-silver-coated 8-mm-wide polyester graft implanted end-to-end in the infrarenal aorta. At the end of implantation, 10 6 colony forming units (CFUs) S. aureus in 0.3 ml suspension were inoculated directly on the graft surface. Blood samples assayed for white blood corpuscles (WBCs) and C-reactive protein (CRP) were taken before implantation and on the postoperative days 2, 5, 7, 11 and 14. Two weeks after implantation, the perigraft swabs were analysed for S. aureus or contaminants. CFUs of S. aureus were quantified and logarithmised. Student's t-tests, repeated measurement analysis of variance (ANOVA) and chi-square test were employed to compare the two grafts. Results All pigs developed graft infection. There were no statistically significant differences between the silver-coated and non-silver-coated grafts in the quantity of S. aureus, macroscopic signs of infection and postoperative changes in the temperature, WBC and CRP. Conclusions Silver–coated polyester grafts failed to prevent graft infections after inoculation with 10 6 S. aureus in 0.3 ml suspension in a porcine model.