As for the substance, the Wikipedia reference is worth reading. Coma - Wikipedia. Many patients, at least in the past, who were hospitalized because of the brain trauma, were getting medications to achieve a state of medically i nduced coma. read more
Imagine this. You are lying in a hospital bed, in a coma, apparently dead to what is happening around you. But you experience it all the same, hear what is being said about and to you, and try in vain to communicate with your loved ones and the world outside. read more