Interesting to read that some of the US based patients on here are encouraged to drink on the day of their surgery. Here in the UK, my experience over numerous surgeries and 4 knee surgeries, I've never been allowed to eat after midnight the day before/of surgery and only been allowed sips of water. That's been the case whether I've had general anaesthetic or spinal. I've booked in at an hospital for surgery in the past at 7am, having had nil by mouth and not gone into surgery until 5pm. I was starving and dehydrated by the time I got back from the recovery room. I understand the reasons I've been given before is to avoid nausea it's just interesting to see the comparative difference on this forum.