Self-Expanding Hemostatic Polymer for Control of Exsanguinating Extremity Bleeding

Abstract

Prehospital management of exsanguinating extremity injuries (EEI) includes direct compression or tourniquets or both. Direct compression may be ineffective in deep wounds and requires a person committed to compressing. Tourniquets may cause severe ischemic damage and may be ineffective in proximal wounds. This study aims to examine a new self-expanding hemostatic polymer (SEHP) for control of EEI. In contact with blood, the polymer absorbs the aqueous component of blood and exerts a tamponade effect by expanding against the walls of the wound cavity. Twenty-one pigs were subjected to a validated and reproducible model of lethal proximal extremity injury by transecting soft tissues and the femoral vessels. The pigs were left to bleed uncontrollably for 3 minutes and then randomized to receive either a standard compression dressing (Control group, N = 10) or SEHP (SEHP group, N = 11). After 5 minutes of manual compression, the dressing or SEHP were left in the wound and the animals resuscitated more than 2 hours. One animal in each group died soon after the injury before application of the dressings and was removed from final analysis. SEHP animals had lower blood loss (1358 mL +/- 97 mL) than the Control animals (2028 mL +/- 177 mL, p = 0.006). The mortality was 55% in the Control group and 0% in the SEHP group (p = 0.006). SEHP is a novel, light, and portable material to control EEI effectively. It does not require another person for compression nor does it compromise the circulation. As EEI occurs with alarming frequency in the battlefield, SEHP may not only present an optimal hemostatic method for military applications but also be useful in the civilian prehospital setting.