[wacki]

The biggest worry is him choking on his vomit. It's not a good idea to leave him alone with a full stomach.

If you can't miss your flight and you are worried about him dieing just stick your finger down his throat. If he pukes then the number one cause of death has been all but eliminated. If he doesn't puke because his gag reflex has been sedated from the alcohol then you have a bit of a problem. You can try Syrup Of Ipecac once, then again in 20 minutes, and if that doesn't work then you MUST NOT LEAVE. If he is sweating, clammy skin, dialed pupils, fast/slow breathing/heartbeat, or unable to be woken up no matter how hard you smack him, then I wouldn't leave without forcing him to puke or getting someone to watch him. Those symptoms are not required for alcohol poisoning.

Also, remove all hard objects surrounding the bed. If he falls off the bed he must not hit his head on anything hard. Leave water by the bed, put him on his left side, etc.