First Aid Advance for Serious Trauma

Researchers are reporting a new sprayable foam that can stop major internal or external bleeding without needing to compress the wound, a first-aid advance desperately needed by first responders and trauma surgeons.

Whether a person suffers a major injury in an auto accident or on the battlefield, one of the leading causes of death is blood loss. The National Trauma Institute says hemorrhage leads to 35 percent of all deaths that occur before an injured patient gets to a hospital. It is responsible for 40 percent of all trauma-related deaths in the first 24 hours.

Now bioengineers and scientists at the University of Maryland, College Park and Massachusetts General Hospital say they have created a polymer-based foam that causes blood cells to clump together. Learn more below.

The active ingredient in the foam is a biopolymer called hydrophobically modified chitosan, which is derived from the shells of shrimp and other crustaceans. It works by turning blood into a “self-supporting gel.” Its mode of action is different from the body’s natural clotting factors, so it can be used even on a patient who has received blood-thinning drugs.

Since it doesn’t require compression to work, it could potentially be used on major injuries to the trunk of the body–like a gunshot wound to the abdomen–which are difficult to stop from bleeding. It could also be used in emergency surgical situations where major internal bleeding is occurring. In tests on pigs, the foam reduced blood loss from a liver injury without compression by 90 percent compared to control animals. It continued to work for an hour.

“The challenge in preventing deaths due to hemorrhage is to intervene as soon as possible after the injury occurs and to rapidly arrest the bleeding from the injury,” the authors write in a study published recently in the journal ACS Biomaterials Science & Engineering. “We hypothesized that the foam would be able to achieve and sustain hemostasis without the need for compression, and this is indeed borne out by the results.”



They say their results are promising, but much more work needs to be done before their biopolymer-based foam starts working on battlefields and in ambulances.

Interested to learn more about how military surgeons have learned to save patients in the worst conditions? Read more here. Or check out this shot that also holds promise to control hemorrhaging.

Gifs above: Immobilization of blood by hmC foam. The foam of hmC is introduced into a tube containing 5 mL of heparinized bovine blood. The foam rapidly expands and overflows out of the tube. The self-supporting nature of the foam allows it to act as a physical barrier to blood flow due to gravity. In addition, the interaction of blood cells with the active ingredient (hmC) leads to the clustering of blood cells and thereby to the containment and immobilization of blood. Gifs created from video. Caption and video courtesy of Dowling et al./ACS.