[wrs]

The few studies seem to show it’s not correlated with anesthesia. There was a supposed “pumphead syndrome” that blamed cardiopulmonary bypass machines for it, but one of the few studies done didn’t find that correlation either. The most plausible thing I’ve seen is that it’s somehow an effect of inflammation, as more and more things seem to be. Surgery is a major trauma, and although you aren’t awake for it, your body is just as traumatized.