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(Bullets + you) / e = death, but why?

  1. May 26, 2005 #1

    Pengwuino

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    (Bullets + you) / e = death, but why? :)

    lol ok im wondeirng something. When your hit with a bullet, what really kills you? Shock, loss of blood, what? Or well, ive been told its loss of blood but why would losing blood kill you? Whats the actual biological process/problem that arises that kills you?

    Ok and to make this less general... what happens in these specific situations

    1) bullet penetrates your lung

    2) bullet penetrates your heart

    3) bullet penetrates your brain (and lets say it wasnt that poewrful of a bullet as to just completely decimate your entire brain)

    4) any other spot not commonly associated with being almost instantly fatal.
     
    Last edited: May 26, 2005
  2. jcsd
  3. May 26, 2005 #2
    Depends where you get shot.

    Could be internal bleeding..or lack of having a head on your body, among other things.
     
  4. May 26, 2005 #3

    Pengwuino

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    hmm yah this has too many possibilities... ill clarify.
     
  5. May 26, 2005 #4
    i'm not professional or anything, so just take my awnsers as assumptions
     
  6. May 26, 2005 #5

    Pengwuino

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    Yah but why do those results kill you.
     
  7. May 26, 2005 #6

    Moonbear

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    In the case of a heart wound (or a wound to any of the major vessels surrounding the heart), you'd bleed out before help even arrived. Plus, the heart itself is severely traumatized and incapable of pumping any remaining blood, so none of your other vital organs are receiving any oxygen or nutrient supply to continue functioning either, and even a transfusion on the scene by paramedics isn't going to do much good if the heart can't pump. That sort of injury is most likely to be a DOA.

    In the case of a wound to the lung, two factors, one, you also have bleeding, and may have struck one of the large pulmonary arteries or veins that would leave you to bleed out quickly, second, any hole into the thoracic cavity (same is true for a wound to the heart or through the diaphragm) is going to leave you unable to breathe (breathing requires negative pressure applied to the outside of the lung from the expansion of the thoracic cavity in order to draw air into the lungs). The bleeding would lead to a quicker death than the lack of breathing, but in either case, you haven't got long before there is too little oxygenated blood getting to the vital organs. In addition, the blood flooding the lungs (no longer contained in blood vessels but getting into the parts where air is supposed to be) would have the same effect as drowning.

    A wound to the head would depend on what part of your brain and how much of it was injured. You can survive a head wound (whether or not you'd have any cognitive abilities intact) if brain regions that control vital organ functions (such as respiration and cardiac function) are spared. Keep in mind that with a head injury, the hole created by the bullet may not be what kills you, but the blood filling the brain and the swelling of the brain in response to injury that causes more extensive brain injury than the bullet hole itself. The brain is also very susceptible to infection, especially fungal infection, when penetrated by anything that's not sterile (it's hard to get medications across the blood-brain barrier; few broad-spectrum antibiotics will cross to treat bacterial infections, and I'm not even sure what options are available for antifungal treatment of brain infection).

    Other fatal injuries would come from wounds to the abdomen that damage other vital organs and major blood vessels. Slower death would occur from sepsis if intestines were hit.

    On the periphery (arms and legs), unless a major artery is hit and nobody can apply appropriate pressure or a tourniquet quickly enough to control the bleeding, then it probably wouldn't be immediately fatal. The risk then would be development of subsequent infection. If the infection remains local, it could go as far as requiring amputation of a limb, but if the infection is carried through the blood supply and becomes systemic, depending on how the "bug" responds to antibiotic treatments, it may be fatal.
     
  8. May 26, 2005 #7

    selfAdjoint

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    The fact of the matter is, as Pascal says, it doesn't take a mountain to fall on us to kill us, a handful of dirt taken the wrong way can do it. Nor do we need an ocean to drown us, a cup of water that goes down wrong will do it.

    It's one of those glass half empty/glass half full things. If you look at us one way it's amazing how tough we are and the awful things we can survive. But you look the other way and it's easy as pie to kill us. These two facts about us have been known at least since the stone age, if not since our common ancestor with the chimpanzees. They form the basis for warfare.
     
  9. May 26, 2005 #8

    LURCH

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    Perhaps you're looking for a more "thermodynamic" explanation of death. Every process in the universe can be understood as movement of energy from one place to another, physical "life" being no exception. In the case of animal life (the kind that humans have) energy is introduced into the system in a stored chemical form (food). This stored chemical energy is released in a controlled way to power the processes we refer to as "life". In this regard, the human body is not so different from any other kind of engine; we eat fuel, we inhale oxygen, the oxygen bonds with the fuel releasing energy to power the act of living.

    If a bullet destroys the trachea, interrupting breathing, there is no oxygen being put to the fuel, and the "engine of life" stalls. The same is likely to happen with any major damage to the lungs. If the bullet strikes the heart, and stops it from pumping, neither fuel nor oxygen is supplied to the body and again, the engine stops. If the bullet passes through the brain stem, or severs the spinal cord just below the brain, the electrical signals that activate the various mechanisms will be cut off and again, the engine stops.

    For the purposes of this discussion, the main difference between the human body and an automobile engine is that living tissue is extremely high maintenance. All of the cells in your body are only a few moments away from rotting where they stand. Only the constant supply of fuel, oxygen, and raw materials maintains these very fragile tissues. If a car engine is left for several months or a year without running, it may seize up and never start again. When the human body stops running, irreplaceable parts begin to fall apart almost immediately, rendering the body incapable of restarting.
     
    Last edited: May 26, 2005
  10. May 26, 2005 #9

    DocToxyn

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    As already addressed, rapid bleeding out or disrupting the nervous system are the two main ways to dispatch a living creature. To speak to the bullet's perspective, in terms of how it does it's work, it obviously has some force behind it and therefore an element of physical impact, but this typically does not do the killing. How strong the impact is will determine how far the bullet penetrates, also included in this is projectile design and makeup which will also determine how much it expands. If it expands alot and quickly, it will penetrate less. A successful bullet will give both good penetration and expansion which will allow it to potentially disrupt more vital targets such as blood vessels and/or the nervous system.
     
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