intoxicated to the point of impossibly blurred vision, incomprehensible slurred speech, and an inability to hear anything over the sound of the blood pounding in your ears
The level of drunkenness one reaches when he/she is blacked out and is no longer able to pronunciate words in any sort of fashion. In other words the persons are blind / deaf / dumb.
Sir Tommy Pickles: Dude, check out Roxy! She's hitting on everyone, falling all over the place and I can't even understand a word she's saying.
Mo'Nasty: I know dude! She is completely "Hellen Kellered" right now.
When the sex is so good, they're left incapacitated. Inability to walk, talk, hear, see, or even think clearly, at least temporarily. To be Hellen Keller'ed is to be in a state of euphoria.
M: OMG, J totallyHelen Keller'ed me this morning! It took an additional two hours to get out of bed this morning, had to watch a movie to recover before brekky!
When you are getting head, and pull your dick out and cum in the girls eyes. While you're doing this you clap you're hands over her ears (ya know hard enough so she cannot hear for a little bit). Now she can't see or hear, just like Hellen Keller!