This is a story related to my mother by my grandfather after a heart surgery. It was a private experience to him, and so was not broadcast to the whole family.
My grandfather was a Colonel in the Army during World War II, and was thus entitled to veteran's benefits, receiving his medical care at the Oak Knoll naval base in Oakland, California. After a heart attack in the mid 1980s, he received a bypass surgery at the base's medical center.
As he reported to my mother, he died during this surgery. He didn't experience a tunnel of light, but he did float upward out of his body to the ceiling. He said that his nose was to the ceiling, and he could see the texture up close. He wanted to turn around to see what the doctors were doing, but he didn't know how. He became very frustrated by his inability to control his spirit body. However, he listened intently to everything the doctors were saying.
At some point he was back in his physical body, and when he awoke he told the doctors, "I died, didn't I?" They were surprised that he knew that, and answered in the affirmative. He then repeated to them the content of their conversations during his death, and they again confirmed his accuracy.
I was not told about this until years after my grandfather passed away (the final time). I know he was a good and religious man all of his life, so no change in that respect was noticeable. However, he did begin to urgently get his temporal affairs in order, making arrangements for his eventual passing. It was as if he knew his remaining time was short.
On a related note, the night my grandmother passed, as she lay in bed with my mother sitting beside her, she sat up, staring at a corner of the room with her arms outstretched and calling my grandfather's name. She eventually calmed down and fell asleep. My mother left the room for a short while, and when she returned, my grandmother was gone. It seems my grandfather came to greet his wife when it was time for them to be reunited.