Polymeric Materials for Hemostatic and Surgical Sealant Applications

Abstract

Commercial hemostatic agents and surgical sealants do not meet the current clinical need. The available options suffer from a variety of shortcomings including high costs, short shelf lives, difficult preparations, and concerns over safety. This work aims to utilize synthetic polymers to develop alternative approaches that have the potential to improve outcomes from traumatic injuries and surgeries while minimizing risk and cost. The first aspect of this research focuses on the development of hemostatic hydrogel particles. These spherical hydrogels with a narrow size distribution were synthesized via inverse suspension polymerization. A cationic monomer was utilized in the hydrogel formulation to facilitate rapid swelling, leading to the formation a physical barrier to blood loss. Coagulation studies demonstrated the ability to cause localized aggregation through charge interactions with erythrocytes while reducing clotting activity in the bulk. This mechanism allows the hydrogel to quickly block blood flow and may mitigate thrombotic complications at distal sites. Hemostatic efficacy was exhibited by decreases in both the time to hemostasis and mass of blood loss in rat liver puncture and tail amputation injury models when compared to compression with gauze alone. The second aspect of this research focuses on the development of a synthetic surgical sealant. This work is centered on the investigation of a polymer fiber mat deposition method called solution blow spinning. This fabrication technique allows for the rapid in situ generation of polymer fibers, offering the ability to conformally deposit polymeric materials directly on the surgical site of interest. Solution blow spinning was utilized to deposit a body temperature responsive, biodegradable polymer blend. Above a critical temperature, the two phase fibrous polymer mat transitioned into a one phase polymer film. This transition resulted in plasticization and promoted polymer-substrate interaction, leading to increased adhesion. Sealant efficacy was demonstrated in a cecal intestinal anastomosis mouse model, where the polymer blend was used to supplement sutures. Both burst pressure and survival rate were significantly improved over the suture-only control.