DARPA has awarded more funding to researchers who are testing a type of expandable foam that could stop internal bleeding long enough to get soldiers off a battlefield. The foam, developed by Arsenal Medical and presented earlier this year before the American Association for the Surgery of Trauma (AAST), is meant to stop internal hemorrhages that can't be compressed with traditional approaches. It's injected into the chest as a pair of separate chemicals, which expand when they come into contact with each other. The result is a thick foam that spreads and solidifies around the chest cavity, stopping bleeding until the patient can be taken to surgery. At that point, it can be removed in a single block.

The research is part of DARPA's Wound Stasis System program, which began in 2009. Preliminary results from September's AAST meeting suggests that this foam could provide a major boost to short-term survival rates: pre-clinical trials in pigs showed an 8 percent survival rate over three hours with existing care, but a 72 percent rate with far less blood loss for those that were also injected with the foam. It's still a big jump from there to battlefield medical care, and it will only help in cases where blood loss is life-threatening but the wound is otherwise survivable. That said, it's still a promising technology that DARPA program manager Brian Holloway says could make an impact on up to half of survivable wounds in the battlefield — and presumably plenty in the civilian world as well.