Batman prepares himself for every eventuality, and if he can't-- well, that's impossible, he's Batman.
Bruce Wayne took a year out from being Batman to become better. To get away from his grim and gritty demons and emerge a more effective crime fighter. That involved travelling the world, having his fears cut away from him by-- well, I'll show you later maybe. But what he did was, he confronted death. Death. And then he was bad-ass-er.
So obviously, after the "Thogal" ritual, Bruce had some questions. Leading to a conversation with a monk who had some very sinister overtones going for him.
Holy shit! Batman's been poisoned! What's the Caped Crusader to do?!
Batman is so awesome that, as force of habit, whenever he dines with someone he switches cups because he's that damn effective. Even off-guard he's not meaning he's the greatest crime fighter ever. That's the point of this. Even when he's not Batman, he's Batman, and you can never trap him.
Right, so, the point: You can never stop Batman. You can leave the country (as in The Dark Knight) and he'll kidnap you right out of your own office tower. You can send him hurtling into the past and he'll fight and punch and think his way to the present, because he's the World's Greatest Detective (more on that later). Batman is awesome.