I've found a paper about Ethanol as a general anesthetic and in their introduction they state
[..] ethanol can produce a state of
general anesthesia and historically
has been used for this purpose (Dundee
et al., 1969). Ethanol causes amnesia
and loss of consiousness in man, and
in experimental animals can cause
immobility in response to a noxious
stimulus. Immobility in response to a
noxious stimulus is the endpoint of
the most common operational definition
of general anesthesia.
The article cited inside that quote is "Use of alcohol in anesthesia" which I can't access.
It seems ethanol has been used as an anesthetic, although it is probably difficult to administer and most likely very dangerous. Most anesthetics have a very narrow therapeutic range, so the amount needed to kill someone is not that much higher than the amount needed for the drug effect.
With ethanol you will have the problem that many people will probably throw up before you can get enough alcohol into them to render them unconscious.