Hiroshima by John Hersey:
A few hours after the operation, a ligature of one of the blood vessels into the lung cavity gave way, and Dr. Sasaki suffered severe hemorrhaging for nearly a week. One day toward the end of that time, as he continued to cough up blood and grew worrisomely feeble, there gathered around him what he construed as a death-watch: his wife, Dr. Hattori, the hospital matron, several nurses. He thanked them, said goodbye to his wife, and died.
Or, rather, he thought he died. Some time later, he regained consciousness and found himself on the mend.