Most military battlefield casualties die before reaching a surgical hospital. Of those soldiers who might potentially survive, most die from uncontrolled bleeding.
In some cases, there's not much medics can do -- a tourniquet won't stop bleeding from a chest wound, and clotting treatments that require refrigerated or frozen blood products aren't always available in the field.
That's why University of Washington researchers have developed a new injectable polymer that strengthens blood clots, called PolySTAT. Administered in a simple shot, the polymer finds any unseen or internal injuries and starts working immediately.
The new polymer, described in a paper featured on the cover of the March 4 issue of Science Translational Medicine, could become a first line of defense in everything from battlefield injuries to rural car accidents to search and rescue missions deep in the mountains. It has been tested in rats, and researchers say it could reach human trials in five years.
In the initial study with rats, 100 percent of animals injected with PolySTAT survived a typically-lethal injury to the femoral artery. Only 20 percent of rats treated with a natural protein that helps blood clot survived.
"Most of the patients who die from bleeding die quickly," said co-author Dr. Nathan White, an assistant professor of emergency medicine who teamed with UW bioengineers and chemical engineers to develop the macromolecule.
"This is something you could potentially put in a syringe inside a backpack and give right away to reduce blood loss and keep people alive long enough to make it to medical care," he said.
The UW team was inspired by factor XIII, a natural protein found in the body that helps strengthen blood clots.
Normally after an injury, platelets in the blood begin to congregate at the wound and form an initial barrier. Then a network of specialized fibers -- called fibrin -- start weaving themselves throughout the clot to reinforce it.
If that scaffolding can't withstand the pressure of blood pushing against it, the clot breaks apart and the patient keeps bleeding.
Both PolySTAT and factor XIII strengthen clots by binding fibrin strands together and adding "cross-links" that reinforce the latticework of that natural bandage.
"It's like the difference between twisting two ropes together and weaving a net," said co-author Suzie Pun, the UW's Robert J. Rushmer Professor of Bioengineering. "The cross-linked net is much stronger."
But the synthetic PolySTAT offers greater protection against natural enzymes that dissolve blood clots. Those help during the healing process, but they work against doctors trying to keep patients from bleeding to death.
The enzymes, which cut fibrin strands, don't target the synthetic PolySTAT bonds that are now integrated into the clot. That helps keep the blood clots intact in the critical hours after an injury.
"We were really testing how robust the clots were that formed," said lead author Leslie Chan, a UW doctoral student in bioengineering. "The animals injected with PolySTAT bled much less, and 100 percent of them lived."
The synthetic polymer offers other advantages over conventional hemorrhaging treatments, said White, who also treats trauma patients at Harborview Medical Center.
Blood products are expensive, need careful storage, and they can grow bacteria or carry infectious diseases, he said. Plus, the hundreds of proteins introduced into a patient's body during a transfusion can have unintended consequences.
After a traumatic injury, the body also begins to lose a protein that's critical to forming fibrin. Once those levels drop below a certain threshold, existing treatments stop working and patients are more likely to die.
In the study, researchers found PolySTAT worked to strengthen clots even in cases where those fibrin building blocks were critically low.
The UW team also used a highly specific peptide that only binds to fibrin at the wound site. It does not bind to a precursor of fibrin that circulates throughout the body. That means PolySTAT shouldn't form dangerous clots that can lead to a stroke or embolism.
Though the polymer's initial safety profile looks promising, researchers said, next steps include testing on larger animals and additional screening to find out if it binds to any other unintended substances. They also plan to investigate its potential for treating hemophilia and for integration into bandages.
Funding came from the National Institutes of Health and its National Center for Advancing Translational Science, the UW Institute of Translational Health Sciences, the Washington Research Foundation, an NIH-supported UW Bioengineering Cardiovascular Training Grant and discretionary funds from private donations.
Jennifer Langston | EurekAlert!
Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg
New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences