Pressure is one of the best tools that medics have to fight bleeding, but they can’t use it on severe wounds near organs. Here, compression could do more harm than good. First responders have no way to effectively dam blood flows from these noncompressible injuries, which account for the majority of hemorrhagic deaths. The new foam could help stop bleeding in these types of injuries.
It relies on chitosan, a biopolymer that comes from processed crustacean shells. By modifying the chitosan, the developers gave the material the ability to anchor blood cells into gel-like networks, essentially forming blood clots. The researchers dispersed the modified chitosan in water to create a fluid they could spray directly onto noncompressible wounds."
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