Yesterday was his turn and I came away with an interesting catch-22 of anesthesia.
He mentioned that anesthesia is designed to work within a specific pH range in the body (around 7.2 to 7.4, slightly basic). But he'd recently had a patient who was so torqued up about the dentist visit that he'd sufficiently altered his body chemistry through the release of acidic by-products of adrenaline dumps and from having his muscles contracted for an extended period of time. The result of his body's pH becoming more acidic (probably around 6.7 or thereabouts) was that the anesthesia could not work on him.