Dr. Maurice Rawlings, MD, a heart surgeon, has written a number of books on the near-death experience. He has written about the true events of many patients being resuscitated on the operating table and speaking about just having come back from hell.
http://video.google.com/videoplay?docid=-5910699532828872069 « click link to start video
http://video.google.com/videoplay?docid=-5910699532828872069 « click link to start video