An all titanium transcutaneous access device (TAD) for peritoneal dialysis

描述（由申请人提供）：腹膜透析（PD）和新兴药物治疗需要长期经皮通路。由于经皮器械会刺破皮肤，而皮肤是细菌进入的正常屏障，因此感染是一个长期的重大问题。本项目的目的是设计和测试全钛经皮穿刺器械（TEE），该器械对出口部位感染的抵抗力明显高于现有腹膜透析导管。该装置采用微孔钛金属（MTM），以在出口部位获得稳定的上皮连接，抑制细菌进入，并促进改善出口部位卫生。MTM是一种用于软组织应用的新材料。多孔金属表面提供了复杂的三维基质，其内部几何形状完全可调。结缔组织增生到多孔金属中会形成物理屏障，防止细菌进入，并且还限制可能导致鼻窦形成的上皮向下生长。初步研究表明，与传统腹膜透析导管上使用的聚合物纤维表面相比，该材料引起的异物反应最小，几乎没有炎症。在材料附近未发现异物巨细胞，其被包封在薄的胶原组织囊中，其与材料的附着超过组织的拉伸强度。这些特性使该材料特别适合这种应用。在第I阶段，我们将设计、构建和测试全钛腹膜透析管，并使用成年绵羊动物模型在8周研究中对其进行评价，使用Sparkhoff腹膜透析管作为对照。我们将描述出口部位的愈合情况，并将采用细菌挑战试验来比较新器械与传统腹膜透析导管防止细菌进入的能力。腹膜透析和新兴医学治疗需要长期经皮通路。当经皮装置刺穿皮肤时，细菌进入、出口部位感染的正常屏障在长时间内是一个显著的问题。本项目的目的是设计和测试一种全钛经皮穿刺器械（TEE），该器械设计为抗感染并提供稳定的皮肤界面。

DESCRIPTION (provided by applicant): Chronic transcutaneous access is needed for peritoneal dialysis (PD) and new emerging medical therapies. Since a transcutaneous device breeches the skin, the normal barrier to bacterial entry, infection is a significant problem over long periods. The objective of this program is the design and testing of an all-titanium transcutaneous access device (TAD) that will be significantly more resistant to exit site infection than existing PD catheters. The device employs microporous titanium metal (MTM) to obtain a stable epithelial junction at the exit site, inhibit bacterial entry, and facilitate improved exit site hygiene. MTM is a new material for soft tissue applications. The porous metal surface provides a complicated three-dimensional matrix whose internal geometry is fully adjustable. Connective tissue proliferation into the porous metal creates a physical barrier to prevent bacterial entry, and it also limits epithelial down-growth that can lead to sinus tract formation. In preliminary studies, it has been shown that this material provokes a minimal foreign body response with virtually no inflammation in comparison to polymer fiber surfaces used on conventional PD catheters. Foreign body giant cells are not found adjacent to the material, which is encapsulated in a thin, collagenous tissue capsule whose attachment to the material exceeds the tensile strength of the tissue. These are characteristics that make the material uniquely suitable for this application. In Phase I, we will design, build, and test the all-titanium TAD and evaluate it using an adult sheep animal model in studies of 8 week duration using Tenckhoff PD catheters as a control. We will characterize healing at the exit site, and a bacterial challenge test will be employed to compare the ability of the new device to prevent bacterial entry versus a conventional PD catheter. Chronic transcutaneous access is needed for peritoneal dialysis and new emerging medical therapies. As a transcutaneous device breeches the skin, the normal barrier to bacterial entry, exit site infection is a significant problem over long periods. The objective of this program is the design and testing of an all- titanium transcutaneous access device (TAD) designed to be resistant to infection and provide a stable skin interface.