Shear-Thinning Biomaterials as Hemostats and Embolic Agents

Reginald Avery
Massachusetts Institute of Technology
Graduate Student

Abstract: 

Internal bleeding can be difficult to treat considering the inaccessibility of the bleeding site without invasive open surgery. In many surgical areas, minimally invasive techniques are becoming more popular to minimize patient discomfort and restrict the treatment only to areas where it is needed. Internal bleeding would likewise benefit from this approach but many of the developed hemostats such as gauzes or hemostatic powders are not conducive to internal delivery. Those materials that are for internal use (e.g. metallic coils, liquid embolic agents, and plastic microparticles) can be expensive, require expertise to deliver, or be toxic to the local environment. Using shear-thinning biomaterials (STBs), we are able to develop a material that can be delivered using clinical tools used in minimally-invasive procedures and effectively reduce bleeding times or occlude vascular to treat internal bleeding. The STB, composed of gelatin and a synthetic silicate nanoparticle, forms a physically associated hydrogel that is stable against physiological temperatures and conditions. In vitro, ex vivo, and in vivo experiments highlight the hydrogel stability against physiological pressures and its reduction of bleeding times by 77 % compared to controls. Additionally, its performance in anticoagulated conditions suggests its utility independent of the state of physiological coagulation, which can be hindered or lacking after injury or during surgery. This feature is lacking in many hemostats or embolic agents and motivates continued exploration of the material for use in surgical or emergency situation.

Date of Talk: 

April 13, 2017