"It felt as though nothing would ever work again—as though the anesthetist had removed everything apart from my soul." That's a quote from a woman who woke up during dental surgery some 15 years ago but was unable to move because of the paralyzing drugs she had been given to stop reflex movements. Her story serves as a sort of foreword to a report published last month on the largest-ever study of the nightmare phenomenon. Over a full year beginning in 2012, every patient who reported "accidental awareness during general anesthesia" (AAGA) at a hospital in Ireland or the UK had his or her case noted; 300 cases were then investigated, the New Scientist reports in a piece picked up by the Washington Post. The worst part of the experience? In many cases, the aforementioned paralysis, not the pain. "Pain was something they understood, but very few of us have experienced what it’s like to be paralyzed," the study author explains. "They thought they had been buried alive." In most cases, AAGA took place before or after the actual surgery, and didn't last more than five minutes. Even so, 51% of people reported distress at the scenario, describing sensations of choking, tugging, or stitching, CBS News reports.
Some patients experienced difficulty breathing; four said they feared they were dying, and two reported that they believed they were actually dead. Some reported an awareness without pain (one said it felt like "being in a crypt," with no working body parts beside the brain and ears). But in another case, the patient "reported auditory and tactile recall of laryngoscopy and intubation and the start of the surgery. The patient wanted to scream but could not move or speak. The patient developed nightmares, waking up crying in a cold sweat recalling events repeatedly." Such lingering issues weren't uncommon: The report noted that in 41% of cases there was moderate to severe longer-term harm. (The aforementioned pain-free patient experienced PTSD, notes the report.) The good news? The study found just one case of AAGA per 19,000 surgeries using general anesthesia, whereas previous smaller studies found the rate might be as high as one in 500. But since this study only looked at cases volunteered by patients rather than questioning every patient, one anesthetist thinks it likely missed many incidents.