Bleeding internally? Seal it with this DARPA foam

[Aepsilons]

@SvenSvensonov , @Horus , @Manticore , @FaujHistorian , @500 et al,

Talk about science fiction coming to reality!This will change battlefield medical aid...

----------------

Bleeding internally? Seal it with this DARPA foam

While any soldier dreads the idea of being shot, sustaining an internal abdominal injury from an explosion or other impact can be far worse. Bleeding from wounds that can't be compressed causes some 85 percent of preventible battlefield deaths.

As part of DARPA's Wound Stasis program, Arsenal Medical has developed an injectable polymer foam that expands inside the body to stanch internal bleeding.

The concept of foam growing in the body reminds me of that 1980s B-horror film "The Stuff," but apparently it's effective.

Based on testing in pigs, DARPA says the product can control hemorrhaging in an abdominal cavity for at least an hour, a critical window to get the soldier to a medical facility.

"During testing, minimally invasive application of the product reduced blood loss six-fold and increased the rate of survival at three hours post-injury to 72 percent from the eight percent observed in controls," DARPA said in a release.

Results of testing were presented at the American Association for the Surgery of Trauma 2012 annual meeting (PDF).


The polyurethane polymer foam forms inside the body when two liquid phases are injected and react with one another. The liquid expands to about 30 times its volume and conforms to the internal features of the abdomen, as seen in the animation below.

The foam can also expand through pooled and clotted blood to reach the source of the bleeding. In testing, it took surgeons less than a minute to remove the foam, which comes out as a solid block.

I wouldn't want to have that stuff inside me for long, but I certainly wouldn't complain if it could save my life.

Arsenal is developing the foam for civilian use in acute hemorrhage and other applications. Meanwhile, DARPA is preparing to get FDA approval for it.

"According to the U.S. Army Institute of Surgical Research, internal hemorrhage is the leading cause of potentially survivable deaths on the battlefield, so the Wound Stasis effort should ultimately translate into an increased rate of survival among warfighters," DARPA program manager Brian Holloway was quoted as saying in the release.

"If testing bears out, the foam technology could affect up to 50 percent of potentially survivable battlefield wounds."

Bleeding internally? Seal it with this DARPA foam - CNET

 

[SvenSvensonov]

@SvenSvensonov , @Horus , @Manticore , @FaujHistorian , @500 et al,

Talk about science fiction coming to reality!

----------------

Bleeding internally? Seal it with this DARPA foam

While any soldier dreads the idea of being shot, sustaining an internal abdominal injury from an explosion or other impact can be far worse. Bleeding from wounds that can't be compressed causes some 85 percent of preventible battlefield deaths.

As part of DARPA's Wound Stasis program, Arsenal Medical has developed an injectable polymer foam that expands inside the body to stanch internal bleeding.

The concept of foam growing in the body reminds me of that 1980s B-horror film "The Stuff," but apparently it's effective.

Based on testing in pigs, DARPA says the product can control hemorrhaging in an abdominal cavity for at least an hour, a critical window to get the soldier to a medical facility.

"During testing, minimally invasive application of the product reduced blood loss six-fold and increased the rate of survival at three hours post-injury to 72 percent from the eight percent observed in controls," DARPA said in a release.

Results of testing were presented at the American Association for the Surgery of Trauma 2012 annual meeting (PDF).


The polyurethane polymer foam forms inside the body when two liquid phases are injected and react with one another. The liquid expands to about 30 times its volume and conforms to the internal features of the abdomen, as seen in the animation below.

The foam can also expand through pooled and clotted blood to reach the source of the bleeding. In testing, it took surgeons less than a minute to remove the foam, which comes out as a solid block.

I wouldn't want to have that stuff inside me for long, but I certainly wouldn't complain if it could save my life.

Arsenal is developing the foam for civilian use in acute hemorrhage and other applications. Meanwhile, DARPA is preparing to get FDA approval for it.

"According to the U.S. Army Institute of Surgical Research, internal hemorrhage is the leading cause of potentially survivable deaths on the battlefield, so the Wound Stasis effort should ultimately translate into an increased rate of survival among warfighters," DARPA program manager Brian Holloway was quoted as saying in the release.

"If testing bears out, the foam technology could affect up to 50 percent of potentially survivable battlefield wounds."

Bleeding internally? Seal it with this DARPA foam - CNET

I foresee a few problems. Getting the stuff out, allowing the wound to start healing while the stuff is still inside and and avoiding additional damage while pulling it out, getting foams stuck on tissue or organ matter, the expansion of the foam can cause additional trauma, tearing and ripping of the wounded sight. Ever had caulk dry to your hand? Tearing it off can rip skin with it and with an expanding foam such as this I foresee the same issues. These are issues that need to be sorted out. Also, if you are bleeding profusely you will need help from someone else. This isn't an EpiPen that can be self administered by jamming it into your leg while bleeding to the point of a lack of consciousness. This foam needs to be accurately inserted into a wound site. I like the idea and trust DARPA to do the right thing, but work still needs to be done to ensure this is safe and effective to use.

Remember: pigs don't have to do this themselves while bleeding and taking incoming fire, they are strapped down and someone else is administering the foam.

 

[Aepsilons]

I foresee a few problems. Getting the stuff out, allowing the wound to start healing while the stuff is still and and avoiding additional damage while pulling it out, expansion of the foam can cause additional trauma, tearing and ripping of the wounded sight. Every had caulk dry to your hand? Tearing it off can rip skin with it and with an expanding foam such as this I foresee the same issues. These are issues that need to be sorted out. Also, if you are bleeding profusely you will need help from someone else. This isn't an EpiPen that can be self administered while bleeding to the point of a lack of consciousness. I like the idea and trust DARPA to do the right thing, but work still needs to be done to ensure this is safe and effective to use.

Definitely the points you pointed out have to be addressed. I also concur with you that there might be some damage to tissue when trying to remove the foam , especially when copious amounts are administered. I hope that they can find ways to ameliorate this. But the fact that these biomedical scientists / biomedical engineers created this just really amazes me. I'm just amazed at the shear ingenuity of Americans. I couldn't help but associate this article with the Halo videogame series.

 

[VCheng]

The foam is biodegradable in situ.

 

[TankMan]

I foresee a few problems. Getting the stuff out, allowing the wound to start healing while the stuff is still inside and and avoiding additional damage while pulling it out, getting foams stuck on tissue or organ matter, the expansion of the foam can cause additional trauma, tearing and ripping of the wounded sight. Ever had caulk dry to your hand? Tearing it off can rip skin with it and with an expanding foam such as this I foresee the same issues. These are issues that need to be sorted out. Also, if you are bleeding profusely you will need help from someone else. This isn't an EpiPen that can be self administered by jamming it into your leg while bleeding to the point of a lack of consciousness. This foam needs to be accurately inserted into a wound site. I like the idea and trust DARPA to do the right thing, but work still needs to be done to ensure this is safe and effective to use.

My thoughts exactly, you hit the nail on the head with the issues you described. DARPA most probably has some solutions to those. It'd be awesome if they make it work though, not only in warfare but first responders/ ambulance crews/ disaster relief... the potential is great.

 

[Aepsilons]

The foam is biodegradable in situ.

So is it really biodegradable? I'm wondering what enzyme catalyzes its metabolic breakdown.

 

[SvenSvensonov]

The foam is biodegradable in situ.

No it's not. Check this from DARPA.Mil

"In tests, removal of the foam took less than one minute following incision by a surgeon. The foam was removed by hand in a single block, with only minimal amounts remaining in the abdominal cavity, and with no significant adherence of tissue to the foam. Features appearing in relief on the extracted foam showed conformal contact with abdominal tissues and partial encapsulation of the small and large bowels, spleen, and liver. Blood absorption was limited to near the surface of the foam; the inside of the foam block remained almost uniformly free of blood."

2012/12/10 DARPA Foam Could Increase Survival Rate for Victims of Internal Hemorrhaging

It seems they've solved the problems I thought would occur, and this is good, but the stuff still needs to be extracted via a surgeon.

 

[VCheng]

So is it really biodegradable? I'm wondering what enzyme catalyzes its metabolic breakdown.

The expansion puts enough pressure on the wound to reduce bleeding, and does not require accurate injection. Once the pressure has stabilized, the mixture slowly loses its internal expansion and begins to breakdown. It is then slowly carted off by the macrophages and completely gone within a few weeks.

 

[VCheng]

No it's not. Check this from DARPA.Mil

"In tests, removal of the foam took less than one minute following incision by a surgeon. The foam was removed by hand in a single block, with only minimal amounts remaining in the abdominal cavity, and with no significant adherence of tissue to the foam. Features appearing in relief on the extracted foam showed conformal contact with abdominal tissues and partial encapsulation of the small and large bowels, spleen, and liver. Blood absorption was limited to near the surface of the foam; the inside of the foam block remained almost uniformly free of blood."

2012/12/10 DARPA Foam Could Increase Survival Rate for Victims of Internal Hemorrhaging

That is the chunk of foam that does not interact with the wound.

 

[Aepsilons]

The expansion puts enough pressure on the wound to reduce bleeding, and does not require accurate injection. Once the pressure has stabilized, the mixture slowly loses its internal expansion and begins to breakdown. It is then slowly carted off by the macrophages and completely gone within a few weeks.

This is just simply amazing. And then its cleansed in the lymphatic system until it's re-circulated into the circulatory system via the left subcleivian vein. Just...simply brilliant.

 

[SvenSvensonov]

That is the chunk of foam that does not interact with the wound.

This part says otherwise;

"Features appearing in relief on the extracted foam showed conformal contact with abdominal tissues and partial encapsulation of the small and large bowels, spleen, and liver. Blood absorption was limited to near the surface of the foam; the inside of the foam block remained almost uniformly free of blood."

This means the foam is interacting with the tissue. There is no information on its ability to be biodegraded, unless you have a link that says otherwise.

Here's an other link worth reading Injectable Foam Blocks Internal Bleeding on the Battlefield - Scientific American

This link states the the next step is to make it biodegradable, not that it is.

And a quote that highlights the problems I found are still an issue;

"Although Arsenal Medical’s foam has a lot of potential, it still needs some work before it is field ready. After the material solidifies, it can cause bruising. In addition, the reaction between the two liquids generates heat, which raises the temperature of surrounding tissue by about 2 or 3 degrees Celsius. Sharma says this temperature increase is on par with a high-grade fever. Some patients might also have an allergic reaction to the foam."

 

[Aepsilons]

No it's not. Check this from DARPA.Mil

"In tests, removal of the foam took less than one minute following incision by a surgeon. The foam was removed by hand in a single block, with only minimal amounts remaining in the abdominal cavity, and with no significant adherence of tissue to the foam. Features appearing in relief on the extracted foam showed conformal contact with abdominal tissues and partial encapsulation of the small and large bowels, spleen, and liver. Blood absorption was limited to near the surface of the foam; the inside of the foam block remained almost uniformly free of blood."

2012/12/10 DARPA Foam Could Increase Survival Rate for Victims of Internal Hemorrhaging

It seems they've solved the problems I thought would occur, and this is good, but the stuff still needs to be extracted via a surgeon.

Good point.

One thing that comes to my mind would be instance of an expanded immune reaction. While it may not be a problem to some patients, i'm wondering if instances of hyperimmunity may be a liability. Given that the foam would be considered as an antigen.

 

[VCheng]

This part says otherwise;

"Features appearing in relief on the extracted foam showed conformal contact with abdominal tissues and partial encapsulation of the small and large bowels, spleen, and liver. Blood absorption was limited to near the surface of the foam; the inside of the foam block remained almost uniformly free of blood."

This means the foams is interacting with the tissue. There is no information on its ability to be biodegraded, unless you have a link that says otherwise.

Here's an other link worth reading Injectable Foam Blocks Internal Bleeding on the Battlefield - Scientific American

This link states the the next step is to make it biodegradable, not that it is.

And a quote that highlight the problems I found are still an issue;

"Although Arsenal Medical’s foam has a lot of potential, it still needs some work before it is field ready. After the material solidifies, it can cause bruising. In addition, the reaction between the two liquids generates heat, which raises the temperature of surrounding tissue by about 2 or 3 degrees Celsius. Sharma says this temperature increase is on par with a high-grade fever. Some patients might also have an allergic reaction to the foam."

Good point.

One thing that comes to my mind would be instance of an expanded immune reaction. While it may not be a problem to some patients, i'm wondering if instances of hyperimmunity may be a liability. Given that the foam would be considered as an antigen.

The isocyanate phase acts as a type of superglue at the wound interface and is definitely biodegradable:

Patent US4804691 - Method for making a biodegradable adhesive for soft living tissue - Google Patents

It also does not elicit any strong immune reactivity.

 

[Aepsilons]

The isocyanate phase acts as a type of superglue at the wound interface and is definitely biodegradable:

Patent US4804691 - Method for making a biodegradable adhesive for soft living tissue - Google Patents

It also does not elicit any strong immune reactivity.

Thanks for that clarification, Sir. Btw, are you a Medical Doctor ?

 

[SvenSvensonov]

The isocyanate phase acts as a type of superglue at the wound interface and is definitely biodegradable:

Patent US4804691 - Method for making a biodegradable adhesive for soft living tissue - Google Patents

It also does not elicit any strong immune reactivity.

But this isn't the only ingredient in the foam and other ingredients can cause immune responses. From the link I provided:

"One liquid is a polyol, a type of alcohol. The other is made of isocyanates, a family of highly reactive chemicals widely used in the manufacture of flexible and rigid foams."

"Isocyanates are powerful irritants to the mucous membranes of the eyes and gastrointestinal and respiratory tracts. Direct skin contact can also cause marked inflammation." - that's an immune response.

CDC - Isocyanates - NIOSH Workplace Safety and Health Topic

We have more than one ingredient and while one may not cause issues, other's might. Also keep in mind that while something might be biodegradable on its own, when combined with other ingredients its properties can change.