Sleeping pills awakening coma patients?

There are thousands of coma patients worldwide and the info that Ambien or other-named sleeping pill DO wake some coma patients up, must have been spread.....so why arent newly awkened victims coming to light? Why isnt it presribed to every single coma patient on earth just in case? If it is...why isnt it reported or documented for the general public?

I dont get why we only heard of the miracle (ok joining of axioms or electrical impulses in the brain) for such a short time but why every single case wasnt reported upon. For each family...the good or bad facts would be major...so why the silence?

Please dont answer if you dont know...but any scientist, healthworker or FDA person....SPEAK UP because Im at a loss as to why such an important study isnt accessible on the net. Its not that new...and its infuriating that there seem to be no statistics or proper worldwide investigation. Surely no-one would leave any person in a flux if the cure was a pill away?