Evidence that ketamine could be used to treat complex regional pain syndrome and depression has always been mitigated by the drug's side effects-hallucinations and anxiety, in particular.

In the journal Anesthesiology, a scientist vividly describes his own experience in the "k-hole" when he was sedated with ketamine for an emergency electrocardioversion procedure.1 At the end of the short piece, he relays what his physician had observed during the same period. The resulting contrast indicates that a practitioner who administers ketamine might have no idea what the patient perceives during the procedure.

"It felt like I had been sucked into an enormous kaleidoscope and was bouncing endlessly from one massive mosaic to another. There was also a vaguely audible static, a chaotic buzzing noise that added to my sense of being trapped in some unknown realm that was deeply frightening," wrote Craig Platt, PhD, professor of psychology at Franklin Pierce University in Rindge, New Hampshire, in the September issue of the journal.

"As time passed and the journey continued, it became increasingly clear to me that whatever was happening was permanent. There was no escape. I remember briefly pondering whether this is what happens when you die, but somehow the question seemed moot," Platt wrote.

He had come to the emergency department because of atrial fibrillation resulting from a mitral valve leak. He had experienced this before, as he awaited surgical repair of the valve.

"Procedural sedation with propofol had worked well for me in previous cardioversions, but today the treating physician had chosen to use the dissociative agent ketamine, primarily because my blood pressure was low and ketamine wouldn't have the depressant effect on cardiovascular function that propofol has," he wrote.

In a postscript, he notes that he felt the need to understand more about his reaction to the drug, and found it was not uncommon. That led him also to consider how it could have been mitigated.

"I can imagine that adding a benzodiazepine in advance might have been effective in my case, but I wonder how the need for [as needed] administration after the fact could possibly be ascertained in a situation like this, since at the time of my greatest distress I was neither moving nor speaking."

Indeed, he said, his emergency department physician later said that all he observed was an understatement of a physical expression, the slightly "furrowed brow" of the title.

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