Foams with Enhanced Rheology for Stopping Bleeding

Area of Science:

• Biomaterials Science
• Hemostasis Research
• Polymer Chemistry

Background:

• Torso bleeding is a leading cause of death, often uncontrollable by direct pressure.
• Existing hemostatic foams lack sufficient barrier strength to prevent blood loss effectively.

Purpose of the Study:

• To develop and evaluate a novel class of aqueous foams with enhanced rheological properties for improved hemorrhage control.
• To investigate the hemostatic efficacy of foams formulated with hydrophobically modified chitosan (hmC) and hydrophobically modified alginate (hmA).

Main Methods:

• Aqueous foams were generated *in situ* using a double-barrelled syringe, combining hmC and hmA precursors.
• Foam rheological properties, including modulus and yield stress, were characterized.
• Hemostatic efficacy was assessed using animal wound models, comparing hmC-hmA foams to hmC-only foams.

Main Results:

• The hmC-hmA foams exhibited a mousse-like texture with high modulus and yield stress, attributed to coacervate formation around gas bubbles.
• These foams demonstrated superior mechanical integrity and barrier function compared to hmC-only foams.
• Animal studies confirmed that hmC-hmA foams were more effective at curtailing bleeding.

Conclusions:

• The novel hmC-hmA foams possess enhanced rheological properties, forming a robust barrier against severe bleeding.
• These advanced hemostatic foams represent a significant improvement over existing technologies for managing life-threatening torso hemorrhage.