FWD: A new bandage
Rohit Khare (rohit@uci.edu)
Mon, 17 May 1999 12:07:37 -0700
>Date: Thu, 13 May 1999 21:35:21 -0700
>From: Jon Callas <jon@callas.org>
>
>
>Hope of Survival Wrapped in a Simple Bandage
>_______________________________________
>
> Army, Red Cross Think They've Found a Way
> to Stop Deadly Hemorrhages -- Fast
>
> By Avram Goldstein
> Washington Post Staff Writer
> Wednesday, May 12, 1999; Page B01
>
> When Army surgeon John B. Holcomb helped set up a
> military hospital for American troops in Somalia in
> 1993, it was the most advanced medical facility in that
> part of the world. Battlefield doctors had every high-tech
> medical tool -- even a CAT scanner.
>
> Yet when a vicious firefight with Somalians erupted in
> Mogadishu on Oct. 3, causing 80 American casualties,
> including 18 deaths, the surgeon was reduced to
> techniques doctors have used for 2,000 years to stop
> severe bleeding. He cinched arteries with fiber ties and
> packed wounds with gauze sponges in the hope that
> blood would clot and patients would be saved.
>
> But that wasn't enough for three soldiers with severe
> bleeding. One whose leg was blown off at the hip by a
> rocket grenade received 46 pints of donor blood but died
> anyway. All three might have survived if doctors could
> have controlled hemorrhaging, Holcomb said.
>
> "It was very frustrating to me to watch these guys die,"
> he said. When Holcomb came home, he volunteered for
> another Army mission, this one based in Washington
> area laboratories: to find a way to save soldiers under
> fire, along with the 50,000 Americans who bleed to
> death on the streets and in hospitals every year.
>
> Now those scientists, at Walter Reed Army Institute of
> Research in Silver Spring and the American Red Cross
> in Rockville, are closing in on an invention they think
> will accomplish that mission.
>
> It's a deceptively simple medical device: a bandage
> loaded with dried, highly concentrated blood-clotting
> proteins that can halt even severe arterial bleeding
> within two minutes.
>
> The four-inch-square bandage contains the blood
> proteins fibrinogen and thrombin in dried form. When
> they come in contact with blood, they combine to form
> fibrin and create an extremely strong scab that becomes a
> glue-like seal over the wound. When held against
> bleeding tissue, the bandage will halt the hemorrhage
> and give rescuers time to get the patient to a hospital.
>
> Researchers expect their product to profoundly alter
> emergency medicine in this country, reduce the demand
> for donations to replace lost blood, and generate as much
> as $400 million a year in sales. They see the day when
> the bandages will be carried in police cars and
> ambulances, and even in first-aid kits.
>
> "Imagine you have one of these in a glove box and you
> encounter someone hanging upside down, bleeding from
> a gash in the neck in a car on the side of road," said Col.
> John Hess, the scientist in charge of blood research at
> Walter Reed who is credited with dreaming up this
> product in the late 1980s. "You can open the bandage,
> slide on a rubber glove, call 911 on the cell phone.
> While you're talking, you kick out the window and you
> can stuff this thing in there and hold it for a minute and
> simply stop that bleeding.
>
> "The appeal of that to you for your family on a camping
> trip is probably the same as to a soldier trying to take
> care of somebody who is badly injured while under
> fire."
>
> Doctors are delighted because the bandage safely
> supercharges a natural process and doesn't rely on
> devices or substances that need to be removed later from
> the body.
>
> The developers of the bandage have published at least
> eight articles about the technology in medical or military
> journals, including a January report in the Journal of
> Trauma, and more are in the works. A 1997 article in
> Surgical Clinics of North America reported that blood
> loss in animals treated experimentally with the bandages
> was 67 percent lower than in those that received
> traditional gauze packing for identical injuries.
>
> "We're taking advantage of the clever design that God
> developed," said Martin J. MacPhee, one of the Red
> Cross researchers. "I think the increase in survival rates
> will be dramatic, and it should be available at some
> point for medicine chests."
>
> Fibrin sealants have been in use in Europe for decades.
> Since 1985, doctors at the University of Virginia in
> Charlottesville also have mixed up their own batches of
> the stuff and used it in about 4,000 operations of all
> kinds.
>
> But the material there is not ready for instant use and is
> available only in operating rooms. Last year, the Food
> and Drug Administration approved several commercial
> products that also are restricted to surgical uses.
>
> The new product is at least 3 1/2 years from FDA
> approval. The Red Cross plans to take 18 more months
> before launching a one-year clinical trial, followed by a
> one-year FDA evaluation of whether the bandage is safe
> and effective. FDA officials want to see evidence that
> the fibrin won't cause infections or allergic reactions.
>
> But scientists think the biggest question isn't whether the
> fibrin sealant bandage works, but whether it will be too
> expensive.
>
> "This would be very well used, but everybody in
> medicine is looking with an eye to the cost of it," said
> Barbara M. Alving, director of blood diseases and
> resources at the National Heart, Lung and Blood
> Institute. "The whole world is extraordinarily
> cost-conscious."
>
> Because fibrinogen and thrombin now are extremely
> expensive, each small bandage could cost several
> hundred dollars in commercial production. But because
> no company has been selected yet to produce that
> bandages under license from the American Red Cross,
> the exact costs are unclear. MacPhee said the price is
> expected to fall if fibrinogen is produced in volume
> through animals.
>
> Red Cross researcher William M. Drohan said scientists
> already have shown that they can genetically engineer
> farm animals to produce enough of the ingredients to
> meet worldwide needs, which would be less expensive
> and avoid the risks of using potential contamination from
> human donor blood.
>
> Drohan has shown that pigs with an altered genetic
> structure can produce up to 1,000 times as much
> fibrinogen in their milk as can be produced by the same
> volume of human donor plasma. The work is going on at
> a farm in Blacksburg, Va.
>
> "You can make material that has no ability to transmit
> human viruses," Drohan said. "We can make an
> unlimited supply to treat the entire world population
> with a small number of animals."
>
> Drohan said that 80 pigs could produce that much, and if
> more material were needed, the Red Cross could shift to
> cows, which produce more milk than any other animal.
> Thrombin can be produced in test tubes in adequate
> supply, he said.
>
> The bandages could be a boon to the military in wartime
> conditions. Considering that 50 percent of battlefield
> deaths are caused by bleeding, military doctors say the
> Army's $2.2 million investment in the project so far has
> been money well spent.
>
> "This fibrin bandage is the single most important
> advance in technology for the military," Adm. Mike
> Cowen, surgeon general to the Joint Chiefs of Staff, told
> a recent gathering of American Red Cross officials in
> Rockville. "We applaud and celebrate what you have
> done."
>
> Even before the researchers win approval for human
> trials of their bandage, Red Cross scientists are looking
> ahead to the second-generation uses of their products.
>
> A foam product now in development would spread fibrin
> sealant to difficult-to-access spots in the body and stop
> bleeding from narrow traumatic injuries, such as bullet
> or stiletto-type wounds.
>
> Because the fibrin sealant adheres to damaged tissue for
> weeks before dissolving, researchers also see a time
> when it could be used to deliver time-released drugs to
> the site of an injury, even as it controls bleeding.
>
> Antibiotics could be mixed into the fibrin and placed on
> a site to treat infection, without requiring a patient to
> take pills that treat the entire body. That limits the drug
> treatment to the area that needs it, ensures that a patient
> won't forget a dose and makes it less likely that bacteria
> would build up resistance to the drug.
>
> At the end of the process, the fibrin sealant is absorbed
> by the body without a trace.
>
> "You get release of drugs locally. They do their job and
> are slowly diffused away in small concentrations that
> have no effect at other sites," said Christopher J.
> Woolverton, a microbiologist at Kent State University
> who has used fibrin in animal studies.
>
> Other researchers are using fibrin as a "scaffold" to
> deliver anesthetics, chemotherapy drugs and genetically
> engineered growth proteins that direct new cells to
> become bone, muscle or nerve so they can regrow bone
> or regenerate damaged tissue.
>
> Jeffrey O. Hollinger, who researches the regrowth of
> human cells at the Oregon Health Sciences University,
> said he has used fibrin as the platform for regenerating a
> long bone in the leg of a rabbit.
>
> "The end result is indistinguishable in function and
> physical appearance from Mother Nature's," he said.
>
> For now, however, the American Red Cross and the
> Army will keep the focus on preventing blood loss with
> the bandage.
>
> "It's going to be big," Hess said. "Once you know this
> exists, are you truly going to be comfortable not having
> one?"
>
> Holcomb, now chief trauma researcher at the U.S. Army
> Institute of Surgical Research in Texas, where he
> continues animal research on the bandages, said they
> will change medicine.
>
> "It's allowing people to think creatively a little bit now,"
> he said. "As it becomes FDA approved, surgeons,
> paramedics and emergency doctors will use it in ways
> we haven't even thought of yet."
>
> Stanching the Flow
>
> The American Red Cross is working in conjunction with
> the U.S. Army to develop a bandage coated with clotting
> substances found naturally in blood. When the bandage
> makes contact with a wound, it creates an "instant scab"
> that stops or slows bleeding until a patient can receive
> care. Here's how the bandage works:
>
> 1.In the case of a bloody injury, the body's clotting
> factors -- the proteins thrombin and fibrinogen -- form an
> insoluble compound called fibrin. Fibrin binds small
> blood cells to other proteins in the wound to form a clot
> and then a scab.
>
> 2.Researchers have developed a way to dry fibrinogen
> and thrombin into powders. A bandage made of surgical
> mesh is coated with a quarter-inch layer of these clotting
> agents, which remain inert until they come in contact
> with blood.
>
> 3. When the bandage is pressed into a wound, fibrinogen
> and thrombin interact immediately with the blood,
> forming the sticky fibrin lattice that adheres to injured
> tissue and forms a scab. Because the bandage contains
> the clotting agents in concentrations 10 to 20 times
> greater than found in the body, bleeding can quickly be
> slowed or stopped. The mesh can be absorbed by the
> body if left in a wound.
>
> In development
>
> Foam: Self-expanding sealant foam intended for bullet
> wounds and other puncture wounds; the foam not only
> reduces bleeding, but traces the path of injury, indicating
> to surgeons other internal sites that need attention.
>
> Dry powder: Intended for seeping wounds, such as
> serious burns, or wounds that bleed persistently, such as
> a scalp laceration.
>
> Test stages
>
> In animal tests, the bandage stopped uncontrollable
> bleeding in seconds. Human tests for the bandage are
> about a year away, and the Food and Drug
> Administration could approve it in 3A years. Human
> tests for the foam are about three years away.
>
>
> (c) Copyright 1999 The Washington Post Company