Small medical sponges are marked with an X that can be seen in X-rays, to avoid leaving them in the body. (RevMedx photos)
XStat uses small medical sponges coated with a blood-clotting agent, loaded into a syringelike injector to help stop bleeding from wounds on the battlefield. To use, a medic inserts the injector into the gunshot wound and pushes the sponges into the body through the syringe. (RevMedx)
Researchers say they have found a way to fight the leading cause of death on the battlefield — bleed-outs — using sterile pellet-shaped sponges that can quickly plug wounds.
The Army-funded technology, a potential life-saver for troops called XStat, uses a light, pocket-sized injector to send 92 sponges into a wound, halting bleeding in 15 seconds, according to the manufacturer, RevMedx. The technology is unique because the sponges, expand as they absorb blood, exerting constant pressure on a wound.
The Oregon-based company has submitted the technology for FDA approval after working to develop it with $5 million in seed money from the Army and Special Operations Command, said John Steinbaugh, vice-president at RevMedx and a former Special Forces medic.
“If you pack gauze into a wound and take your hands off, there’s no pressure on the [blood] vessel,” Steinbaugh said. “Every minute you’re holding pressure, that’s time a medic can’t treat someone else because he’s trying to stop bleeding.”
Hemorrhages were the leading cause of death in 90 percent of the potentially survivable battlefield cases, according to a 2012 Army study.
Army officials see XStat as a way to treat wounds at the junction of the trunk and legs or arms, which pose a challenge for tourniquets.
Medical Research and Materiel Command, at Fort Detrick, Md., is working with the company to bring the technology to soldiers once it receives the FDA’s OK, which Army officials say is imminent. The time frame and cost of fielding it have not been announced.
Col. Dallas Hack, director of the Combat Casualty Care Research Program at MRMC, said XStat has shown promise in laboratory tests. He said he considers it an improvement over combat gauze, which requires constant pressure and “doesn’t get into the wounds very well.”
“It is very good, and we need to get it out for people to start using it, as we have with all of the bandages so far,” Hack said. “The special forces community is very interested in taking this along. It’s at least as good as what we have now, probably better.”
Inspired by Fix-A-Flat, RevMedx initially explored a liquid foam that could be sprayed into a wounds but abandoned the foam concept for several reasons, Steinbaugh said. High-pressure blood flow would push the foam away from the wound; at low temperatures, the liquid could freeze inside the canister and become ineffective; keeping compressed gas canisters on medics was deemed unsafe and impractical; and the FDA approval process for a hemostatic foam drug would have taken too long.
Hack and other Army officials say the service is still pursuing foam as an option.
How the sponges work
In the midst of the company’s research, an intern — inspired by toy dinosaur sponges that expand in water — created the first XStat prototype, according to Steinbaugh.
Unlike kitchen sponges, these disc-shaped sponges are made of special sterile cellulose and coated with chitosan, a clotting agent. They expand into tube shapes that, when saturated with blood, clump together so later they can be easily removed by a doctor.
To keep them from becoming lost inside a patient, they each contain an X-shaped marker that can be spotted with an X-ray.
“The main thing is pressure,” Steinbaugh said. “These sponges go from three millimeters thick to, when they have contact with blood, 50 millimeters. ... One XStat fills the space it would take five rolls of combat gauze to fill.”
A medic would take the syringe-like injector, which can be packed into a pouch on his or her body armor, and depress the plunger to insert the sponges into the wound. The injector’s rubber tip peels back to let the sponges out.
“All the medic has to do is put it close to where he thinks the wound is and inject,” Steinbaugh said.
The applicator is meant to treat arterial bleeding common to wounds caused by high velocity rounds, but RevMedx is developing a smaller version suited to narrow-entrance wound tracks caused by shrapnel, a knife or handgun. The sponges inside the applicator would be single-stacked.
RevMedx is also developing a bandage with sponges embedded in it and a dressing with an inflatable bladder that would maintain pressure on a wound.■