Recent advances in medical hemostatic materials: Mechanisms, evaluation, and clinical perspectives.

Uncontrolled hemorrhage remains a major cause of preventable death in trauma and surgery, yet the performance of hemostatic materials varies markedly with wound geometry, blood flow, coagulation status, and tissue sensitivity. This review critically examines natural polymer-based, synthetic polymer-based, inorganic, and composite hemostats by linking material structure to six principal mechanisms: fluid absorption and surface adsorption, coagulation activation, bioactive-factor delivery, photothermal assistance, adhesive sealing, and microstructural regulation. Beyond cataloging materials, we compare class-specific advantages, failure modes, and safety constraints, and analyze how hemodilution, hypothermia, acidosis, anticoagulation, infection, and high-flow bleeding reshape material performance. We further integrate clinically used products, scenario-based material selection, and a staged evaluation framework spanning mechanistic assays, hostile-condition testing, translational bleeding models, rebleeding assessment, and post-hemostasis safety. Finally, we outline stage-matched pathways for responsive and multifunctional systems. This mechanism-scenario-evaluation framework supports more rigorous design, comparison, and clinical translation of next-generation hemostatic materials.