Hi Ckozz, I happened to just have seen a video or two about a man (Robert Mobley) telling about his coma nightmares (which are fortunately not common). Watching those two videos, should answer your question.
I would warn you and others though, that what he experienced is some of the worst that one can experience, so it's not easy to watch.
*To sum up: When your point of attention is no longer in the PMR due to drug induced unconsciousness, (e.g anesthesia) are you experiencing a dream state or other *real* virtual realities?
There is no general rule here, there are a multitude of experiences possible, from no awareness and recollection to Robert's or your experience, and everything in between.