Zdogg relates a case of a 69 year old man who was subjected to 90 minutes of high-quality CPR during an ordeal in the hospital where he ultimately could not be saved due to his massive aortic dissection. The patient woke up during CPR, but when they stopped, he went unconscious again.
He notes that the underlying theory for CPR is that it is being administered to a dead person and they are not aware of what is happening. This case indicates that is not necessarily the case. Zdogg suggests that perhaps sedation should become standard for administration of CPR.
1 to 2 percent of survivors of out-of-hospital CPR (about 13%) report being aware of what was happening at the time. Multiple studies have found in-hospital CPR success rates between 19% to 57% with only 4% to 24% of patients who receive CPR discharged alive.