What are the dangers of hypothermia?

Circumstance depends: walking/hiking outdoors with hypothermia can make you slow and sleepy, with risk of more damage as you cool down further. Frostbite results when parts of you get too cold and freeze. In a different setting, like after injury or surgery, with heavy bleeding, hypothermia throws off the body's ability to clot and stop the bleeding. Other basic functions get thrown off as well.