This Small Business Innovation Research (SBIR) Phase I project proposes to develop a novel self-sealing material to be applied to the design of durable blood access systems for hemodialysis patients. Current access systems are neither designed for repeated access nor managing bleeding after hemodialysis treatment, and as a result commonly lead to secondary complications. The research aims of the proposal are to: 1) Develop a self-sealing hemostatic material, 2) Create designs suitable for vascular access applications, and 3) Assess safety and efficacy of the designs in a chronic animal model. The research will draw upon knowledge in cross-disciplinary fields to complete the aims of the proposal, and demonstrate enhanced performance relative to commercial predicate technology.
The broader impact/commercial potential of this project will yield a unique and novel material that will create a paradigm shift from the treatment of complications to prevention to create better clinical outcomes and contain costs. Nearly 580,000 people in the United States alone have end stage renal disease (ESRD), and over 400,000 people are treated using hemodialysis as the primary mode of treatment. This materials technology will lead to vascular access devices suitable for the entire hemodialysis patient population, thereby creating an estimated market size of more than $400 million. And this materials technology platform may be applied to a broad range of applications beyond hemodialysis where repeated access and reliable sealing is required.
Conventional materials for cardiovascular applications include expanded-polytetrafluoroethylene (ePTFE) and polyethylene terephthalate (polyester), both of which have demonstrated adequate use for vascular grafting. However, when repeated blood access is needed for hemodialysis, especially with the use of large bore needles (14-16G), these materials have shown to be inadequate, often leading to acute and secondary complications such as venous needle or clot dislodgement, pseudoaneurysm formation, infection, and thrombosis – all of which can be potentially fatal and/or contribute to the greater than $27 billion spent on the treatment of end-stage renal disease (ESRD). Access devices in the recent past, e.g. angioplasty balloons and thrombectomy devices, have largely relied on the occurrence of secondary complications. However, with the increasing ESRD patient population and recently mandated bundled payment by the Centers for Medicaid and Medicare Services there is a clinical and economic demand for more innovative solutions that can produce better outcomes. In the NSF SBIR P1 research proposal a unique approach using a polymer based composite was developed to create a self-sealing materials technology with unprecedented leak resistance after repeated cannulations. Custom computational models were developed using finite element methods to efficiently evaluate various composite designs and determine the basis for initial prototypes. In bench testing, the composite material demonstrated equivalent performance in strength and exhibited better results in a repeated-puncture leak test at 120 mmHg hydrostatic pressure. Preclinical animal testing demonstrated safety and corroborated enhanced sealing during simulated needle cannulation over the course of 60 days. Angiography conducted at the end of the study showed patency. Successful development of the composite material establishes the basis for a novel materials technology that may be useful in interventional applications where access and immediate sealing is required. The initial application is for vascular blood access to address the myriad secondary complications related to hemodialysis.
