There’s room for improvement. Military doctors estimate that, during the most violent years of the wars in Afghanistan and Iraq, blood loss killed about 90 percent of the wounded that might have otherwise survived with better emergency care. To save more lives, a group of veterans, scientists, and engineers known as RevMedx has created a pocket-sized device called XStat: a faster, more effective way to plug wounds. The polycarbonate syringe slides deep into a wound, such as a bullet track. When a user pushes down on the handle, it deposits dozens of pill-size sponges that expand to stem bleeding. Meanwhile, a substance in the sponges fights infection while clotting blood.