The Brutal Potential of Bending.

When I saw the episode of blood bending, a thought came to me. The way that bending can be directly applied to living beings. Bending has a very dark side an evil I hope that is kept is the dark

Fire bending -Instant death, the heart has an electric current, by targeting that current a fire bender could instantly cause defibrillator leading to death. -Soul crushing pain, nerves run on electricity thus the pain receptors in the body could all be simultaneously activated at their full potential, probably doing irrevocable psychological damage.

Earth bending -removal of all calcium from bones would leave most enemies as withering clumps of muscle and tissue.

Water bending- Blood bending, pulling out the 75% water from the body would leave a withered husk.

Air bending-filling lungs with air until chest cavity explodes.

If any of these are not possible that would be nice to know, I don't like these but they are a possibility are they not? Please could you guys show me how I'am wrong, I do not want this to be a possibility in the Avatar universe.