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Biomedicine

Inflatable Device Stops the Bleeding

A fast, efficient balloon-based system could save lives on the street and battlefield.

Uncontrolled bleeding is a major cause of death on the battlefield, and according to military medical experts, it accounts for 80 percent of otherwise preventable deaths. One problem is that there are no effective treatments for deep, penetrating wounds, which are too severe for gauze packing and are in areas where a tourniquet cannot be applied. To stop life-threatening bleeding in such instances, Maynard Ramsey, the chief executive officer and chief technology officer at CardioCommand, a Tampa, FL-based medical device company, has developed a balloon-based system that can be inserted into a wound and inflated in less than 90 seconds.

Inflatable life-saver: A balloon-based device can be inserted into a deep, penetrating wound and inflated in less than 90 seconds to stanch life-threatening bleeding. The balloon is made of polyurethane-coated nylon, and expands to a maximum length of eight inches and diameter of two inches. It conforms to the shape and size of the wound.

The device looks like a long, thin, flexible wand, around which is a tightly wrapped compression balloon covered by a removable sheath. Once a medic inserts the device into the wound, he can inflate it with a hand pump or syringe to a maximum of eight inches long and two inches wide. The balloon conforms to the shape and size of the wound, putting pressure on its walls to stanch bleeding until the patient can be transported to an operating room.

Thousands of people die on the streets and battlefield every day because of stab wounds and gunshot wounds that result in uncontrolled bleeding, says Joseph Garfield, an associate professor of anesthesiology at Harvard Medical School and Brigham and Women’s Hospital in Boston. “Ramsey has developed an ingenious device to combat this problem.”

Ramsey has successfully tested the device in 200-pound pigs, and is currently trying to work with the military to conduct more extensive tests.

“The device is ready to be in the field tomorrow,” says Rutledge Ellis-Behnke, a researcher at MIT, who is also building materials to stop bleeding. He says the new device does have some issues. For example, anyone using the device would need to avoid further damaging tissue while navigating the wound track. Also, a medic using the device could drive shrapnel across a healthy artery and accidentally sever it, he says. But, Ellis-Behnke adds, the device addresses a problem that right now has no solution. “The deployment of it will save lives,” he says.

The balloon is made of two walls of material: the outer wall is nylon coated on the inside with polyurethane; the inner wall is a layer of soft polyurethane. The design makes the balloon resistant to punctures from sharp objects, like shrapnel, that might be inside the wound. The balloon will also conform to the shape of the wound and compress it. Similar balloon devices, used mostly in operating rooms, “stretch when inflated, but they want to take their ‘natural’ shape, and do not therefore contour to fit the wound track,” says Ramsey.

In pieces: The TourniCath (middle, product packaging) looks like a long, thin plastic tube (bottom). It is comprised of a catheter around which is a tightly wrapped compression balloon covered by a removable sheath. When deployed into a simulated wound track (top), the inflated balloon conforms to the shape of the wound.

The CardioCommand device was developed for areas where conventional tourniquets cannot be applied, such as the groin or shoulder. But even tourniquets have drawbacks because they can’t be left on for more than 30 minutes and can cause secondary tissue damage. The new device was also made for puncture wounds too deep and severe for traditional methods of treatment.

The device is part of a recent effort to develop more effective methods to control bleeding from severe trauma. For example, the U.S. military uses a bandage made by HemCon that has chitosan, a blood-clotting agent, to seal a wound and stop the hemorrhaging. The military also uses QuickClot, a pourable product that uses zeolite-based agents to soak up the blood and adhere to the tissue at and around the wound site. Newer methods still in development include a pouch, built by Aurora Flight Sciences, that swells when put inside an injury, and nanoparticles designed to mimic the clotting capability of blood platelets. The nanoparticle research is led by Erin Lavik, a bioengineer at Case Western University in Cleveland.

But, says Ellis-Behnke, “All of these have drawbacks.” They can swell bigger than the wound, putting pressure on and damaging vital organs, or cause clots that can travel to other areas of the body, he says. Also, most are not biodegradable, he says.

No device is as well directed toward the problem of hemorrhage control as CardioCommand’s device, says Steven Glorsky, a trauma surgeon at Brooke Army Medical Center in San Antonio, TX. “This could have huge benefits on the battlefield.”

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