Goëau-Brissonnière O, Leport C, Guidoin R, Lebrault C, Péchère J C, Bacourt F
J Vasc Surg. 1987 May;5(5):743-8.
We developed an animal model to reproduce hematogenous seeding of vascular grafts with Staphylococcus aureus. Expanded polytetrafluoroethylene (ePTFE) grafts were implanted in 41 dogs as thoracoabdominal aortic bypasses for six durations of implantation between 2 hours and 6 months. The inoculum containing an average of 10(8) viable bacteria/ml was then injected intravenously in 1 minute. Normal dog aortas were used as controls. They entrapped very few bacteria (0.7 +/- 1.7 colony-forming unit [CFU]/cm2). Colonization of ePTFE grafts was maximal after 2 hours of implantation (589 +/- 733 CFU/cm2). Bacterial entrapment decreased after 2 days (225 +/- 315 CFU/cm2, p less than 0.001) and 8 days (70 +/- 115 CFU/cm2, p less than 0.001) of implantation, but it was similar after 8 days, 1 month (83 +/- 90 CFU/cm2), or 6 months (93 +/- 143 CFU/cm2) of implantation. Colonization of ePTFE measured after 2 months of implantation (371 +/- 591 CFU/cm2) was significantly higher (p less than 0.001) than after 1 or 6 months of implantation. More than 500 CFU/cm2 were seen in 37% of the prosthetic fragments tested after 2 hours of exposure to blood; 99% of the fragments tested after 6 months of implantation trapped less than 500 CFU/cm2. Scanning electron microscopy showed that staphylococci were mostly seen on native fibrin deposits, particularly after 2 hours and 2 months of implantation. That persistent susceptibility of a flow surface devoid of endothelium to hematogenous bacterial colonization has to be taken into account to prevent delayed graft infections. Furthermore, it would be important to compare the ePTFE with other types of grafts whose healing phenomena are different.
我们建立了一种动物模型，用于再现金黄色葡萄球菌对血管移植物的血源性播散。将膨体聚四氟乙烯（ePTFE）移植物植入41只犬体内，作为胸腹主动脉旁路，植入时间为2小时至6个月，共6个时间段。然后在1分钟内静脉注射平均含10(8) 个活细菌/毫升的接种物。正常犬主动脉用作对照。它们截留的细菌极少（0.7±1.7集落形成单位[CFU]/平方厘米）。ePTFE移植物在植入2小时后定植量最大（589±733 CFU/平方厘米）。植入2天后（225±315 CFU/平方厘米，p<0.001）和8天后（70±115 CFU/平方厘米，p<0.001）细菌截留量减少，但在植入8天、1个月（83±90 CFU/平方厘米）或6个月（93±143 CFU/平方厘米）后相似。植入2个月后测得的ePTFE定植量（371±591 CFU/平方厘米）显著高于植入1个月或6个月后（p<0.001）。暴露于血液2小时后，37%的假体碎片中可见超过500 CFU/平方厘米；植入6个月后测试的碎片中，99%截留的细菌少于500 CFU/平方厘米。扫描电子显微镜显示，葡萄球菌大多见于天然纤维蛋白沉积物上，尤其是在植入2小时和2个月后。为防止移植物延迟感染，必须考虑无内皮的血流表面对血源性细菌定植的持续易感性。此外，将ePTFE与愈合现象不同的其他类型移植物进行比较也很重要。
