The answers come from
Anesthesia & You... Anesthesia for Ambulatory Surgery, an informational document prepared by the American Society of Anesthesiologists through the cooperative efforts of the Society's Committees on Communications and the Committee on Ambulatory Surgical Care.

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What about eating or drinking before my anesthesia?
As a general rule, you should not eat or drink anything after midnight before your surgery. Under some circumstances, you may be given permission by your anesthesiologist to drink clear liquids up to a few hours before your anesthesia.

If you smoke, please refrain.