Injectable hemostatic foam hydrogel for traumatic intra-abdominal hemorrhage

Traumatic abdominal hemorrhage is critically life-threatening, as uncontrolled bleeding in this region can rapidly lead to death. However, there is a lack of effective methods or materials for emergency hemorrhage control, especially for pre-hospital emergency medical services. Here, we report an injectable hemostatic foam (IHF), a norepinephrine-loaded sodium alginate/carboxymethyl chitosan-based foam, which was inspired by physiological hemostasis processes (vasoconstriction, platelet thrombosis, and blood coagulation). IHF possesses good injectability, can rapidly reach the injury site to create a tamponade effect and provide wound site coverage when injected into abdominal cavity during emergency care. Then, the loaded norepinephrine induces vasoconstriction, and the foam interacts with blood to accelerate the formation of platelet thrombosis and blood coagulation. Upon arrival at the definitive point of care, IHF could be disrupted by urea and removed by negative pressure suction. Rat and rabbit liver bleeding models demonstrated its excellent hemostatic ability, significantly reducing blood loss and bleeding time. What's more, in the heparinized rat and rabbit liver bleeding models, which were established to mimic systemic coagulation dysfunction secondary to severe trauma, the IHF hemostatic effect was still excellent. The emergency abdominal hemorrhage model created in rat and porcine liver demonstrated the IHF's effectiveness and safety. Furthermore, no obvious postoperative intestinal adhesion was observed after IHF therapy. Collectively, IHF presents a strategy characterized by low implementation barriers and favorable safety profiles, thereby serving as an effective, safe, and feasible emergency hemostatic intervention for traumatic intra-abdominal hemorrhage.