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Glasgow Coma Scale This is used by EMTs and ER people to determine LOC (Level Of Consciousness). I'm not a medical person, but from my research the DEEP unconsciousness of a coma is generally drug, brain damage or hypothermia related. But ANY injury or condition severe enough to cause deep unconsciousness (blood loss, hypoxia, etc.) is severe enough to cause brain trauma.
And remember, unconscious does not necessarily mean coma.
