Gunshot to the femoral artery? No problem. A team of researchers from the University of British Columbia have been leading the development of a new method for delivering life-saving, blood clotting drugs straight to the source of a wound: particles that can literally propel themselves against the flow of blood using carbon dioxide, like an antacid tablet dropped in water.
"Most dressings that are used to stop bleeding, if it's very severe, they may have trouble stopping that bleeding," Christian Kastrup, an assistant professor in the Department of Biochemistry and Molecular Biology at the University of British Columbia, said via phone. "They can't get that coagulant deep into the wound."
This is because it is often difficult to deliver therapeutic drugs deep into damaged tissue because the drugs cannot fight past the outward flow of blood—a dire problem for those suffering severe trauma. Postpartum hemorrhage, for example, is a leading cause of death of mothers during childbirth, and it is difficult to stem the flow of blood using traditional means when the wound originates inside the body.
In a paper, published today in the journal Science Advances, the researchers found their particles could propel themselves up to 1.5 square centimetres through an aqueous solution, "and deliver therapeutics millimetres into the vasculature of wounds."
When the powder makes contact with blood, the carbon dioxide reacts with the liquid to propel the therapeutic drug it is bound to—a coagulant called tranexamic—deep into the wound and its surrounding damaged tissue. Kastrup said that the the particles the team has developed could be delivered via powder applied to gauze.
According to the study, in five pigs where a traumatic femoral artery hemorrhage was induced, gauze containing the self-propelled drug ensured an 100 percent chance of survival, "whereas only 40% (2/5) survived to 3 hours when treated with gauze" where the same drug was present, but not self-propelled.
The diverse team includes researchers and biochemical engineers from the University of British Columbia, and emergency physicians from the University of Washington and Harvard Medical School.
Now that the discovery phase is complete, Kastrup says the team is now entering the preclinical phase, with the hopes that it could be used on real patients within two to three years.