We expect to come back from general anaesthesia. People consider the dangers of being operated on, but don't seem to think of anaesthesia as being one of them.

(That said, general anaesthesia is way less safe than people seem to regard it, which is why anaesthetists are fully-trained doctors who have specialised, rather than just technicians. And why your anaesthetist can turn you away on the morning of your operation just like that if they're at all unsure.)