It says here (under the mysterious headline “Residents chased from mountain town by wildfire allowed to return home”) that “a sedative called propofol was administered to [President] Bush through an intravenous line” during his routine colonoscopy this morning.

And, curiously, it says here that “Propofol is a diisopropylphenol. This intravenous hypnotic agent produces rapid sedation with minimal excitatory activity, however it has no analgesic properties. The actual mechanism of action is unknown, but it is postulated that propofol mediates activity of the GABA receptors.” (emphasis mine).

So in other words, the President was put to sleep for an operation using a drug the actual mechanism of which we don’t understand.

Apparently this isn’t all too unusual, as it says here that “although researchers have tried, no single explanation for general anaesthesia can be agreed upon.”

Good to know that some things remain mysteries.