• Dec 9, 2009
Thermahelm helmet animation - Click above to watch the video after the break

We're sure this comes as a shock to nobody, but here we go anyway: brain swelling is bad. Very bad. That thick, hard skull surrounding your brain is great at providing a good deal of protection, but when things go awry in a big way, there isn't much room in there to let your brain expand.

Cooling the brain in some manner is apparently a good way to reduce swelling, and a company from the U.K. called Thermahelm has worked up a new motorcycle helmet that incorporates a layer ammonium nitrate and water that instantly mixes in the event of a crash. The chemical reaction will maintain a 37-degree brain temperature, which is said to stave off oxygen loss to the brain.

According to Thermahelm, its technology will add roughly $250 to the cost of a helmet, and the company is currently working on a retrofit kit that will allow riders to install the system in their own helmets. Click past the break to watch a nifty video animating the technology.

[Source: Thermahelm]


ThermaHelmâ„¢ Cooling Helmet in Action


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  • 24 Comments
      • 5 Years Ago
      It's going to cool my 37C brain to 37C?
        • 5 Years Ago
        Mr. Clickerson,

        I Think your missing the point. As a university chemistry student (aha! credibility), I know through thermodynamics that thermal energy (heat) moves from areas of low concentration to areas of high concentration. If blood (temp = ~37.10C) moves through the brain, and the brain is also at a constant temperature (37.10C), no transmission of heat will occur. No matter how much blood passes through there.

        Actually, blood in the body monitors your body temp. So if your brain's temperature were above 37.10C, then your blood would actually carry heat AWAY from your brain, COOLING it. Again, in order to cool the body, a medium at a temperature lower that 37.10C would be required.

        So... this is completely useless.
        • 5 Years Ago
        When you hit your head hard enough, the increased bloodflow heats the area (which causes the swelling).

        I would know, had a severe concussion at the army recently... :-(
        • 5 Years Ago
        OK, nothing against the chem major, but there's a reason why people have majors like physiology and pathology. You guys are ignoring some key pathological reactions. Let's do this generally:

        Let's say you bang your knee against something, not enough to break a bone but enough for it to hurt like a mother and leave a bump. What just happened? Well, the initial trauma is going to release the internal contents of cells. These chemicals irritate the local cells which in turn release chemicals called cytokines, which like messengers to inflammatory cells. In order for these inflammatory cells to get to the site of injury in the tissue, they have to go from the blood into the tissue. This requires them to cross blood vessel walls. The cytokines can also act on the vessel walls by increasing the spaces between the cells in the vessel walls, and the caliber of the vessels themselves. This facilitates the passage of the inflammatory cells across the wall, but unfortunately, this means that you're going to get fluid as well (exudation), which is going to lead to swelling since you now have more fluid in the tissue than normal.

        So that takes care of the swelling. What about the heat? There are two parts to this:

        1. The more blood you have flowing through an area, the more heat is going to be generated. Think about it. When we're really hot (or drink), our skin gets warm. That's because capillary beds in our skin are opened, so that more blood gets to that area and can release the heat that's being carried from the inside of our body. So if all of a sudden, we have a trauma that's causing the vessels in an area to become bigger (from the cytokines), that's going to slow the flow of blood and thus we'll have heat retention in certain areas, rather than just passing through. The brain is also primarily fat, which has a higher heat capacity than water, so it's going to collect that heat energy in greater quantities, thus there's a greater chance of injury.

        2. Inflammatory cells and mediators increase local metabolism. The body is going to try to fix or contain the injury. This takes energy, which is stored primarily as ATP in most cells. Now, to use ATP is kind of like an ICE - you're going to get residual heat in the process of energy transfer from one form to another. Hence, we have heat generation by making and using ATP.

        So what does the cooling (theoretically) do? Well, for one it could cause a decrease in
        the dilation of the vessels, counteracting those inflammatory mediators that will cause exudation (movement of fluid and cells through the wall) and thus preventing tissue swelling. It may have a more direct effect on cell metabolism, but I'm not going to state that that's what happens out and out.

        I hope that helps to clarify.
        • 5 Years Ago
        Increased circulation of 37C fluid raises the temperature to more than 37C?

        I dunno, maybe I shouldn't complain so much, my neighbor made a heart catheter that reduced damage after a heart attack by cooling the area. But it did work from the inside, and it cooled below 37C.
        • 5 Years Ago
        Another stupid comment by LS7.
        • 5 Years Ago
        thats my thoughts exactly. Thats just body temperature. There is no reason why your body (and your brain) would ever get hotter than that. This is a completely pointless gimmick which does absolutely nothing.
      • 5 Years Ago
      $250 will certainly add to the price, but as saying goes "a $5 head wears a $5 helmet".
      • 5 Years Ago
      Wonder how much this weighs , damn helmet alone weighs enough !
      • 5 Years Ago
      you know the saying "i need blah as much as another hole in my head?". Well, guess what. When you have head trauma and your brain is swelling the ER will drill holes in your head to let out some of the pressure. I used to be a paramedic, taking people into the ER is the trippiest thing you can experience. If you ever get a chance, volunteer at a hospital and try to get into the ER. You will see the reason for safety requirements and why you need leathers and helmet when riding a motorcycle. We used to call bikers "donorcyclers", you can figure out why.
      • 5 Years Ago
      last time i heard bigger brain = smarter. N isnt it better to just let the body do what it does, i mean swelling of the brain prob has its meaning, but on the other hand, cooling it isnt so bad, i dunno. $250 isnt that bad. Smaller brain does mean less chance of it touching ur skull
        • 5 Years Ago
        "If it's a small injury, the swelling increases bloodflow, healing the brain faster."
        Errr, no. The swelling does not heal your brain faster, swelling causes the loss of more brain cells and permanent neurological damage, because the neurons in your brain do not regenerate if they die.

        Seriously what's with the ridiculous personal theories on brain injury being posted here? If you don't know what you're talking about don't make up some crackpot theory on brain injury based on some ridiculous "common sense" knowledge you have. You don't get to the moon with common sense mathematics, and you don't do neurosurgery with common sense either so quit it before you kill yourself or other people with stuff that doesn't even qualify to be pseudoscience.
        • 5 Years Ago
        If it's a small injury, the swelling increases bloodflow, healing the brain faster.

        If it's a large injury, ancestral man would have died from it anyways, so it didn't matter that the brain would swell so far as to cut off oxygen from certain regions. But now that we have hospitals and such, we can recover from much more serious accidents.
      • 5 Years Ago
      Couple thoughts:

      1) increased swelling within the closed confines of the skull means increased pressure, which can constrict/crush bloodflow more (or even force the brain downward, which is called herniation). And yes, brain injuries can occur even without skull fracures (think adult version of shaken-baby syndrome)

      2) hypothermia is known to decrease metabolism, and the brain's blood supply regulates itself via its metabolism. Hence the theory here: decreased temperature = decreased bloodflow = decreased swelling.

      3) despite what is known in #2, there has been no conclusive research that hypothermia is protective in cases of trauma (rather than other causes of low oxygen to the brain). Indeed, it's also known that blood tends to clot less well with colder temperatures - not a good thing if you're bleeding into the brain.

      Therefore, the design to maintain a normothermic 37*C is probably a hedge against the uncertainty in medical literature. Besides, most people are actually hotter than 37* under a helmet - many people tend to sweat alot while helmeted, and it's rare that people ride motorcycles in winter.

      And yes, management of head trauma is complex. Focal bleeding, such as a subdural hematoma, can be managed via trephination (craniotomy, or "burr holes"). However, larger, more diffuse bleeds can't - and the swelling can only be managed via meds (inducing a coma) or by a craniectomy - removing parts of the skull.
      • 5 Years Ago
      Swelling is initially caused by greater blood flow, which is a result of the body trying to route more oxygen to repair the damage there. If this is very slight, it is not a problem and accelerates healing time.

      The problem is the brain is encased, so it's very easy for there to be too much swelling, which crushes more tissue and closes off bloodflow to the brain (the crushing and the oxygen deprivation are what do the damage, not the swelling itself). This crushed tissues causes more swelling, and this cycle repeats to disastrous effects.

      Cooling the brain, trepanation, and/or medication can counteract this.
      • 5 Years Ago
      First you need helmet laws. I swear when I was down in TX and saw bikers without helmets going 70mph I thought THEY should win the darwin awards. Then again there are plenty of smart people who could use good organs, so c'est la vie.
        • 5 Years Ago
        Yeah, CO doesn't have a helmet law either and I think it's like a 5:1 ratio of non-helmet wearers to those that actually do wear them.
      • 5 Years Ago
      I am interested to see the company's studies as far as the ammonium nitrate (fertilizer) blowing up. Hopefully that water mixes before fire gets to it in the event of a wreck.
      • 5 Years Ago
      I hate to get technical, but the ammonium nitrate dissolving in the water causes the drop in temperature. Since it is not reacting chemically with the water, its a change of state, not a chemical reaction.
      • 5 Years Ago
      The brain only swells during a trauma, in which case it will not make you smarter. It's also been proven that brain size does not correlate to intelligence amongst humans. Against different species maybe, but the normal variance between humans doesn't make a difference.

      Keeping the brain cool could add vital seconds or minutes until serious brain injury occurs, this could potentially save many lives.
        • 5 Years Ago
        True, but I just meant that it doesn't swell for good reasons...usually only negative ones.
        • 5 Years Ago
        No, the brain can swell for other reasons as well besides trauma, such as infection and ventricular obstruction.
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